ctrl-r key

bugfix: playing failed with tracks of unknown length
keys: added yank keys

.gitignore

@@ -1,3 +1,2 @@
 demo
-muf
-muf.debug.log
+fuzic

scripts/build.sh

@@ -3,16 +3,14 @@
 BOLD="\033[1m"
 GREEN="\033[0;32m"
 OFF="\033[m"
-NAME="muf"
+NAME="fuzic"
 SRC="./src/main.sh"
 
 tmpdir=$(mktemp -d)
-echo "🐔 ${GREEN}Internalize sourced files${OFF}"
+echo "🥚 ${GREEN}Internalize sourced files${OFF}"
 sed -E 's|\. "([^$].+)"$|cat src/\1|e' "$SRC" >"$tmpdir/1.sh"
-echo "🥚 ${GREEN}Internalize awk scripts${OFF}"
-sed -E 's|@@include (.+)$|cat src/\1|e' "$tmpdir/1.sh" >"$tmpdir/2.sh"
-echo "🐔 ${GREEN}Internalize awk libraries${OFF}"
-sed -E 's|@include "(.+)"$|cat src/\1|e' "$tmpdir/2.sh" >"$NAME"
+echo "🐔 ${GREEN}Internalize awk scripts${OFF}"
+sed -E 's|@@include (.+)$|cat src/\1|e' "$tmpdir/1.sh" >"$NAME"
 echo "🥚 ${GREEN}Make executable and cleanup${OFF}"
 chmod +x "$NAME"
 rm -rf "$tmpdir"

share/theme/bw.sh

@@ -7,22 +7,22 @@ FORMAT_LOCAL="|>"
 # Pointer to the track currently playing (playlist)
 FORMAT_CURRENT="->"
 
-# Input prompts
+# Input prompt
 # =============
-# General search prompt
+# Search prompt
 SEARCH_PROMPT="search> "
-# Prompt that takes an artist name as argument
-ARTIST_PROMPT="%s > "
-# Prompt that takes an artist name and a release name as arguments (in that
-# order)
-FULL_PROMPT="%s > %s > "
 
-# Visual representation of current mode
-# =====================================
-# Sign to indicate `normal` mode
-PROMPT_NORMAL="n  "
-# Sign to indicate `insert` mode
-PROMPT_INSERT="i  "
+# Headers
+# =======
+# Header that displays artist's name
+HEADER_ARTIST="%s > "
+# Header that displays the release-group name after artist's
+HEADER_ARTIST_RELEASEGROUP="%s > %s > "
+# Header that in addition to `HEADER_ARTIST_RELEASEGROUP` also shows some
+# release information
+HEADER_RELEASE="%s > %s > %s"
+# The release information is formatted as follows (placeholders implicit):
+HEADER_RELEASE_FORMAT="<<tracks>> tx <<media>> | <<label>> <<country>> <<year>>"
 
 # Artist view
 # ===========

share/theme/simple.sh

@@ -18,22 +18,22 @@ FORMAT_LOCAL="${BLUE}|>$OFF"
 # Pointer to the track currently playing (playlist)
 FORMAT_CURRENT="${WHITE}-->$OFF"
 
-# Input prompts
+# Input prompt
 # =============
-# General search prompt
+# Search prompt
 SEARCH_PROMPT="search: "
-# Prompt that takes an artist name as argument
-ARTIST_PROMPT="artist: %s: "
-# Prompt that takes an artist name and a release name as arguments (in that
-# order)
-FULL_PROMPT="artist: %s / %s: "
 
-# Visual representation of current mode
-# =====================================
-# Sign to indicate `normal` mode
-PROMPT_NORMAL="n)"
-# Sign to indicate `insert` mode
-PROMPT_INSERT="i)"
+# Headers
+# =======
+# Header that displays artist's name
+HEADER_ARTIST="artist: %s"
+# Header that displays the release-group name after artist's
+HEADER_ARTIST_RELEASEGROUP="artist: %s / album: %s"
+# Header that in addition to `HEADER_ARTIST_RELEASEGROUP` also shows some
+# release information
+HEADER_RELEASE="artist: %s / album: %s (%s)"
+# The release information is formatted as follows (placeholders implicit):
+HEADER_RELEASE_FORMAT="<<label>> <<year>>"
 
 # Artist view
 # ===========

src/awk/artists.awk

@@ -1,3 +1,30 @@
+# List artists
+#
+# parameter file_local_artists:    This is an optional parameter with the path
+#                                  to a file with a MusicBrainz artist ID per
+#                                  line.
+# parameter format_person:         This is the format string for single person
+#                                  artists, which includes the <<name>>
+#                                  placeholder.
+# parameter format_disambiguation: This is the format string for the
+#                                  disambiguation part of the artist, with a
+#                                  placeholder <<disambiguation>>.
+# parameter format_group:          This is as format_person, but for music
+#                                  groups.
+# parameter format_local:          String to indicate that there is some music
+#                                  locally available of an artist
+#
+# This awk program takes as input a sequence of lines where the first item is
+# the MusicBrainz artist ID, the second item is the type of the artist
+# ("Person" or "Group"), the third item is the name, and the forth item is a
+# disambiguation string.
+#
+# The output of this script is a sequence of tab-delimited lines where the
+# first item is the format_local string, if some music of that artist is
+# locally accessible, and the empty string otherwise, the second item is the
+# formatted artist string (formatted according to format_person or
+# format_group), the third item is the constant string "0" indicating the
+# parent MusicBrainz ID, and the last item is the MusicBrainz artist ID.
 BEGIN {
   OFS="\t"
   local_artists[0] = 0

src/awk/recordings.awk

@@ -1,3 +1,39 @@
+# List recordings
+#
+# parameter file_local_recordings: This is an optional parameter with the path
+#                                  to a file with a MusicBrainz recording ID
+#                                  per line.
+# parameter format:                The format of a recording line including the
+#                                  placeholders <<med>> for medium number,
+#                                  <<nr> for for track number within a medium,
+#                                  <<title>> for the title, <<artist>> for the
+#                                  artist string, and <<duration>> for the
+#                                  track duration.
+# parameter format_local:          String to indicate that the track is locally
+#                                  available
+# parameter format_current:        String to indicate that the track is
+#                                  "currently playing"
+# parameter current_id:            MusicBrainz track ID of a track to be marked
+#                                  as "currently playing"
+#
+# The input to this awk program is a sequence of lines containing the following fields:
+# Field 1: The MusicBrainz ID of the release this track belongs to
+# Field 2: MusicBrainz ID of this track
+# Field 3: Medium number of this track within the release
+# Field 4: Track number of this track within the medium
+# Field 5: Duration of this track in miliseconds
+# Field 6: Title of this track
+# Field 7: Artist of this track
+# Field 8: Path to decoratoin file of this release
+#
+# The output is a sequence of tab-delimited lines containing the following fields:
+# Field 1: Sort value (to sort the track within the release)
+# Field 2: The string `format_local` if the track is locally available
+# Field 3: The string `format_current` if the track has MusicBrainz ID `current_id`
+# Field 4: The track line to be displayed according to `format`
+# Field 5: The MusicBrainz ID of the release this track belongs to
+# Field 6: The MusicBrainz ID of this track ":" separated from the path to the
+#          decoration file of this release
 BEGIN {
   OFS="\t"
   local_recordings[0] = 0
@@ -9,7 +45,6 @@ BEGIN {
   }
 }
 {
-  gsub("&", "\\\\&")
   parentid = $1
   id = $2
   med = $3
@@ -18,6 +53,8 @@ BEGIN {
   title = $6
   artist = $7
   deco = local_recordings[id] ? $8 : ""
+  gsub("&", "\\\\&", title)
+  gsub("&", "\\\\&", artist)
   # Parse duration
   if (dur) {
     dur = int(dur / 1000)

src/awk/releasegroups.awk

@@ -1,3 +1,69 @@
+# List release groups
+#
+# parameter file_local_releasegroups: This is an optional parameter with the
+#                                     path to a file with a MusicBrainz
+#                                     release-group ID per line.
+# parameter format_release:           Format for the release title with a
+#                                     <<title>> placeholder.
+# parameter format_release_w_artist:  Same as `format_release` but with an
+#                                     additional <<artist>> placeholder.
+# parameter format_year:              Format string for the year part, with a
+#                                     <<year>> placeholder.
+# parameter format_local:             String to indicate that the track is
+#                                     locally available.
+# parameter artist:                   Artist name to compare release-groups
+#                                     artist names against. If the names
+#                                     differ, then the format with <<artist>>
+#                                     placeholder is used (optional)
+# parameter artistid                  MusicBrainz ID of the artist (optional).
+# Then, there are several format strings that indicate the type of a release
+# group. The types are implicit from the parameter names:
+# parameter format_album
+# parameter format_single
+# parameter format_ep
+# parameter format_broadcast
+# parameter format_other
+# Some release groups have also a secondary type. The presence of a secondary
+# type is formatted using
+# parameter format_secondary.
+# The list of all secondary types (implicit from their variable names) are
+# formatted using
+# parameter format_secondary.
+# Each of the secondary types is specified with (the type is implicit from the
+# variable names)
+# parameter format_compilation
+# parameter format_soundtrack
+# parameter format_spokenword
+# parameter format_interview
+# parameter format_audiobook
+# parameter format_audiodrama
+# parameter format_live
+# parameter format_remix
+# parameter format_djmix
+# parameter format_mixtape
+# parameter format_demo
+# parameter format_fieldrec
+#
+# The input to this awk program is a sequence of lines containing the following
+# fields:
+# Field 1: The MusicBrainz ID of the release group
+# Field 2: The primary type
+# Field 3: A ;-delimited string of secondary types
+# Field 4: The original release year
+# Field 5: Title of the release group
+# Field 6: The artist as credited
+#
+# The output is a sequence of tab-delimited lines with the fields:
+# Field 1: Sort value to sort release groups
+# Field 2: The flag `format_local` if the release group is accessible locally,
+#          and "" else.
+# Field 3: Release-group type
+# Field 4: Release-group string
+# Field 5: Release-group year
+# Field 6: Secondary types
+# Field 7: MusicBrainz artist ID of the release group artist, if there is one,
+#          else "0"
+# Field 8: MusicBrainz release-group ID
 BEGIN {
   OFS="\t"
   local_releasegroups[0] = 0
@@ -9,9 +75,9 @@ BEGIN {
   }
 }
 {
-  line_type=""
-  line_sectype=""
-  line_year=""
+  line_type = ""
+  line_sectype = ""
+  line_year = ""
   gsub("&", "\\\\&")
   id = $1
   type = $2

src/awk/releases.awk

@@ -1,3 +1,57 @@
+# List releases
+#
+# parameter file_local_releases:         This is an optional parameter with the
+#                                        path to a file with a MusicBrainz
+#                                        release ID per line.
+# parameter format_release:              Format for the release with the
+#                                        placeholders <<status>>, <<tracks>>,
+#                                        <<media>>, <<year>>, <<country>>, and
+#                                        <<label>>.
+# parameter format_release_title_artist: Format to specify title and artist,
+#                                        with the placeholders <<title>> and
+#                                        <<artist>>.
+# parameter format_release_title:        Format to specify the release title
+#                                        with a placeholder <<title>>.
+# parameter format_release_artist:       Format to specify the release artist
+#                                        with a placeholder <<artist>>.
+# parameter format_local:                String to indicate that the track is
+#                                        locally available.
+# parameter rg_artist:                   Artist name of release group
+#                                        (optional)
+# parameter rg_title:                    Title of release group (optional)
+# parameter rgid:                        MusicBrainz release-group ID
+#                                        (optional)
+# Then, there are several format strings that indicate the status of a release.
+# The status are implicit from the parameter names:
+# parameter release_official
+# parameter release_promotion
+# parameter release_bootleg
+# parameter release_pseudo
+# parameter release_withdrawn
+# parameter release_expunged
+# parameter release_cancelled
+#
+# The input to this awk program is a sequence of lines containing the following
+# fields:
+# Field  1: MusicBrainz ID of the release
+# Field  2: Release status
+# Field  3: Release date
+# Field  4: Number of cover-art images
+# Field  5: Label string (', '-delimited)
+# Field  6: Total number of tracks
+# Field  7: Format (', '-delimited)
+# Field  8: Release country
+# Field  9: Release title
+# Field 10: Artist as credited
+#
+# The output is a sequence of tab-delimited lines with the fields:
+# Field 1: Sort value to sort release groups
+# Field 2: The flag `format_local` if the release is accessible locally, and ""
+#          else.
+# Field 3: Release line
+# Field 4: MusicBrainz release-group ID if present, else "0"
+# Field 5: MusicBrainz release ID followed by ":" and then a path to the
+#          decoration file (if it exists)
 BEGIN {
   OFS="\t"
   local_releases[0] = 0
@@ -30,27 +84,27 @@ BEGIN {
     case "Cancelled": line_status = release_cancelled; break
     default: line_status = ""
   }
-  line = release_format
+  line = format_release
   if (artist != rg_artist && title != rg_title)
-    line = line "\t" release_format_title_artist
+    line = line "\t" format_release_title_artist
   else if (artist != rg_artist && title == rg_title)
-    line = line "\t" release_format_artist
+    line = line "\t" format_release_artist
   else if (artist == rg_artist && title != rg_title)
-    line = line "\t" release_format_title
+    line = line "\t" format_release_title
   else
     line = line "\t"
 
-  sub("<<status>>", line_status, line)
-  sub("<<year>>", year, line)
-  sub("<<tracks>>", trackcnt, line)
-  sub("<<media>>", media, line)
+  gsub("<<status>>", line_status, line)
+  gsub("<<year>>", year, line)
+  gsub("<<tracks>>", trackcnt, line)
+  gsub("<<media>>", media, line)
   gsub("&", "\\\\&", label)
-  sub("<<label>>", label, line)
-  gsub("&", "\\\\&", titel)
-  sub("<<title>>", title, line)
+  gsub("<<label>>", label, line)
+  gsub("&", "\\\\&", title)
+  gsub("<<title>>", title, line)
   gsub("&", "\\\\&", artist)
-  sub("<<artist>>", artist, line)
-  sub("<<country>>", country, line)
+  gsub("<<artist>>", artist, line)
+  gsub("<<country>>", country, line)
   sortk = year ? year : 0
   l = local_releases[id] ? format_local : ""
   print sortk, l, line, rgid ? rgid : "0", id ":" local_releases[id]

src/main.sh

@@ -3,10 +3,10 @@
 set -eu
 
 # The user interface of this application is composed out of the following
-# views.
+# views:
 # - VIEW_ARTIST: Show all release group of an artist
 # - VIEW_RELEASEGROUP: Show all releases within a release group
-# - VIEW_RELEASE: Show track list of release
+# - VIEW_RELEASE: Show track list of a release
 # - VIEW_SEARCH_ARTIST: Interface to search artists on MusicBrainz
 # - VIEW_SEARCH_ALBUM: Interface to search albums (release groups) on MusicBrainz
 # - VIEW_LIST_ARTISTS: Presentation of all artists in the local database
@@ -16,7 +16,7 @@ set -eu
 # - VIEW_QUIT: Exiting view, to terminate the application
 #
 # All views but the last three are handled within a single fzf instance. The
-# views VIEW_SELECT_ARTIST, and VIEW_PLAYLIST run each in a separate fzf
+# views VIEW_SELECT_ARTIST and VIEW_PLAYLIST run each in a separate fzf
 # instance. The last view (VIEW_QUIT) does nothing but terminate the
 # application.
 #
@@ -26,7 +26,7 @@ set -eu
 # the query string can be written.
 #
 # All views and modes are referred to by the following constants. The values
-# are arbitrary but distinct.
+# are arbitrary but must be distinct.
 VIEW_ARTIST="artist"
 VIEW_RELEASEGROUP="rg"
 VIEW_RELEASE="release"
@@ -56,7 +56,7 @@ MODE_INSERT="show"
 # Load playlist tools
 . "sh/playlist.sh"
 
-# Load MusicBrainz and Discogs methods
+# Load MusicBrainz, Discogs, and wiki methods
 . "sh/api.sh"
 
 # Load mpv methods
@@ -80,6 +80,9 @@ MODE_INSERT="show"
 # FZF handlers
 . "sh/fzf.sh"
 
+# Load keys
+. "sh/keys.sh"
+
 # Command-line options that may only be used internally.
 #   --lines
 #   --playback
@@ -89,7 +92,9 @@ MODE_INSERT="show"
 #   --action-gotoartist
 #   --action-draw
 #   --mbsearch
-#   --preview-artist
+#   --preview
+#   --show-keybindings
+#   --remove-from-cache
 case "${1:-}" in
 "--lines")
   # Print lines that are fed into fzf.
@@ -110,7 +115,7 @@ case "${1:-}" in
   "$VIEW_LIST_ARTISTS") list_local_artists ;;
   "$VIEW_LIST_ALBUMS") list_local_releasegroups ;;
   "$VIEW_PLAYLIST") list_playlist ;;
-  "$VIEW_SEARCH_ARTIST" | "$VIEW_SEARCH_ALBUM") fzf_reload_after_change ;;
+  "$VIEW_SEARCH_ARTIST" | "$VIEW_SEARCH_ALBUM") mb_results_async ;;
   esac
   exit 0
   ;;
@@ -270,7 +275,7 @@ case "${1:-}" in
   [ "$q" ] && q="$q "
   printf "show-input+change-query(%s)" "$q"
   # Store current state
-  printf "+change-border-label(%s)+change-list-label(%s)" "$view" "$mbid"
+  printf "+change-list-label(%s)" "$view"
   # Set header
   fzf_command_set_header "$view" "$mbid"
   # Set preview window
@@ -298,21 +303,65 @@ case "${1:-}" in
   # This stops any search being executed and initiates a new query through the
   # MusicBrainz API. The results will be made available through the ``--lines
   # <view>`` command.
-  fzf_handle_change "$2"
+  mb_search_async "$2"
   exit 0
   ;;
-"--preview-artist")
-  # Generate content for artist preview
+"--preview")
+  # Generate content for preview window
   #
-  # @argument $2: MusicBrainz Artist ID
+  # @argument $2: view
+  # @argument $3: MusicBrainz ID of selected item
   #
-  # This prints the text to be displayed in the preview window for the
-  # specified artist.
-  __preview_artist "$2"
+  # This prints the text to be displayed in the preview window.
+  view=$2
+  mbid="${3:-}"
+  case "$view" in
+  "$VIEW_LIST_ARTISTS" | "$VIEW_SEARCH_ARTIST" | "$VIEW_SELECT_ARTIST") preview_artist "$mbid" ;;
+  *) preview_nothing ;;
+  esac
+  exit 0
+  ;;
+"--show-keybindings")
+  # Print keybindings for current view
+  #
+  # @argument $2: view
+  print_keybindings "$2"
+  exit 0
+  ;;
+"--remove-from-cache")
+  # Remove entry from cache to reload
+  #
+  # @argument $2: view
+  # @argument $3: MusicBrainz ID of current object
+  # @argument $4: MusicBrainz ID of selected object
+  case "$2" in
+  "$VIEW_ARTIST")
+    cache_rm_artist "$3"
+    cache_rm_releasegroup "$4"
+    ;;
+  "$VIEW_RELEASEGROUP")
+    cache_rm_releasegroup "$3"
+    cache_rm_release "$4"
+    ;;
+  "$VIEW_RELEASE") cache_rm_release "$3" ;;
+  "$VIEW_LIST_ALBUMS" | "$VIEW_SEARCH_ALBUM") cache_rm_releasegroup "$4" ;;
+  esac
   exit 0
   ;;
 esac
 
+# Load configuration
+. "sh/config.sh"
+
+# Load theme
+. "sh/theme.sh"
+
+# Load tools
+. "sh/tools.sh"
+
+# Load AWK scripts
+. "sh/awk.sh"
+
 # Non-interactive user commands intended to the user. These commands do not
 # require temporary files, fzf, nor the mpv instance.
 case "${1:-}" in
@@ -332,7 +381,22 @@ case "${1:-}" in
   fi
   exit 0
   ;;
-"--reload")
+"--decorate-as")
+  # Decorate the specified directory as given MusicBrainz release
+  #
+  # @argument $2: path
+  # @argument $3: MusicBrainz release ID
+  [ ! "${2:-}" ] && err "You did not specify a directory." && exit 1
+  [ ! -d "$2" ] && err "Path $2 does not point to a directory." && exit 1
+  [ ! "${3:-}" ] && err "You did not specify a MusicBrainz release ID." && exit 1
+  [ ! "$(mb_release "$3" | $JQ '.title // ""')" ] && err "Did you specify a correct MusicBrainz release ID?" && exit 1
+  if ! decorate_as "$2" "$3"; then
+    err "Something went wrong."
+    exit 1
+  fi
+  exit 0
+  ;;
+"--reload-database")
   # Reload database of local music
   #
   # @argument $2: path
@@ -343,7 +407,7 @@ case "${1:-}" in
   [ ! "${2:-}" ] && err "Path to decorated music is missing." && exit 1
   [ ! -d "$2" ] && err "Path does not point to a directory." && exit 1
   info "Reloading information of local music directory $2"
-  load_local "$2" || err "Failed to load local data"
+  reloaddb "$2" || err "Failed to load local data"
   info "Done"
   exit 0
   ;;
@@ -353,30 +417,22 @@ case "${1:-}" in
 Usage: $0 [OPTION]
 
 GENERAL OPTIONS:
-  --help                        Show this help and exit.
+  --help                        Show this help and exit
   --artists                     Default options, list artists of local music
   --albums                      List albums of local music
-  --search-artist [<query>]     Search artist on MusicBrainz
-  --search-album [<query>]      Search album on MusicBrainz
+  --search-artist               Search artist on MusicBrainz
+  --search-album                Search album on MusicBrainz
   --artist <mbid>               List release groups of given artist <mbid>
   --releasegroup <mbid>         List releases in given release group <mbid>
   --release <mbid>              Show release given by <mbid>
-  --ni-search-artist [<query>]  Non-interactive search on MusicBrainz
-  --ni-search-album [<query>]   Non-interactive search on MusicBrainz
 
 MANAGE LOCAL MUSIC:
   --decorate <path>             Decorate directory containing a tagged release
-  --reload <path>               Populate database with decorated local music from <path>
+  --decorate-as <path> <mbid>   Decorate directory as the relase <mbid>
+  --reload-database <path>      Populate database with decorated local music from <path>
 EOF
   exit 0
   ;;
-"--refresh-view")
-  # Recompute main views
-  #
-  # With this method, the content for the views VIEW_LIST_ARTISTS and VIEW_LIST_ALBUMS are recomputed.
-  precompute_view
-  exit 0
-  ;;
 esac
 
 # Interactive user commands
@@ -428,38 +484,25 @@ case "${1:-}" in
 esac
 
 # Start application:
-# - load configuration
-# - load and export theme
 # - load and export preset filters
-# - load and export keys
-# - load and export tools
-# - load and export awk scripts
 # - set title
+# - check for missing data from MusicBrainz
+# - precompute main views
 # - get temporary directory for temporary files
 # - start mpv daemon
 # - enter main loop and start fzf
 
-# Load configuration
-. "sh/config.sh"
-
-# Load theme
-. "sh/theme.sh"
-
 # Load filters
 . "sh/filter.sh"
 
-# Load keys
-. "sh/keys.sh"
-
-# Load tools
-. "sh/tools.sh"
-
-# Load AWK scripts
-. "sh/awk.sh"
-
 # Set window title
 printf '\033]0;%s\007' "$WINDOW_TITLE"
 
+# Check if the required json files are present
+local_files_present || load_missing_files
+# Generate views
+precompute_views
+
 # Generate filenames for temporary files
 tmpdir=$(mktemp -d)
 LOCKFILE="$tmpdir/lock"
@@ -480,25 +523,23 @@ mpv_start
 # mode, we call `hide-input`. To switch to insert mode, we call `show-input`.
 #
 # view: [$VIEW_*]
-# The view is stored in $FZF_BORDER_LABEL. To set the view, call
-# `change-border-label($VIEW)`.
+# The view is stored in $FZF_LIST_LABEL. To set the view, call
+# `change-list-label($VIEW)`.
 #
 # argument: string
 # The argument is stored in $FZF_LIST_LABEL. To set the argument, call
 # `change-list-label($arg)`.
 IN_NORMAL_MODE="[ \$FZF_INPUT_STATE = hidden ]"
-IN_VIEW_PATTERN="[ \$FZF_BORDER_LABEL = %s ]"
+IN_VIEW_PATTERN="[ \$FZF_LIST_LABEL = %s ]"
 IN_LIST_ARTISTS_VIEW="$(printf "$IN_VIEW_PATTERN" "$VIEW_LIST_ARTISTS")"
 FZF_CURRENT_MODE="\$FZF_INPUT_STATE"
-FZF_CURRENT_VIEW="\$FZF_BORDER_LABEL"
+FZF_CURRENT_VIEW="\$FZF_LIST_LABEL"
 FZF_RELOAD_PLAYLIST="reload-sync($0 --lines $VIEW_PLAYLIST)"
 FZF_POS_PLAYLIST="transform:$0 --action-playlistcursor"
 PUT_FZF_KEY_LOGIC="case \$FZF_KEY in space) echo \"put( )\";; left) echo backward-char;; right) echo forward-char;; backspace|bspace|bs) echo backward-delete-char;; delete|del) echo delete-char;; *) echo \"put(\$FZF_KEY)\";; esac"
 while true; do
   case "$VIEW" in
   "$VIEW_SELECT_ARTIST")
-    info "SELECT ARTIST VIEW with ARGS=$ARGS"
-    info "$(echo "$ARGS" | list_artists_from_json)"
     sel=$(
       echo "$ARGS" | list_artists_from_json | $FZF \
         --bind="$KEYS_DOWN:down" \
@@ -513,13 +554,20 @@ while true; do
         --bind="$KEYS_SEARCH_ALBUM:print($VIEW_SEARCH_ALBUM)+accept" \
         --bind="$KEYS_BROWSE:execute-silent:open \"https://musicbrainz.org/artist/{r3}\"" \
         --bind="$KEYS_SHOW_PLAYLIST:print($VIEW_PLAYLIST)+print()+accept" \
+        --bind="$KEYS_KEYBINDINGS:preview:$0 --show-keybindings $VIEW_SELECT_ARTIST" \
+        --bind="$KEYS_SCROLL_PREVIEW_DOWN:preview-down" \
+        --bind="$KEYS_SCROLL_PREVIEW_UP:preview-up" \
+        --bind="$KEYS_PREVIEW_OPEN:show-preview" \
+        --bind="$KEYS_PREVIEW_CLOSE:hide-preview" \
+        --bind="$KEYS_FILTER_LOCAL:change-query($QUERY_LOCAL )" \
         -0 -1 \
         --border="bold" \
         --border-label="Select artist" \
+        --preview-window="right,25%,border-left,wrap,<30(hidden)" \
+        --preview="$0 --preview $VIEW_SELECT_ARTIST {3}" \
         --delimiter="\t" \
         --prompt="$SEARCH_PROMPT" \
         --margin="5%,20%" \
-        --bind="$KEYS_FILTER_LOCAL:change-query('$QUERY_LOCAL' )" \
         --accept-nth="{3}" \
         --with-nth="{1}" || true
     )
@@ -557,6 +605,12 @@ while true; do
         --bind="$KEYS_SEARCH_ALBUM:print($VIEW_SEARCH_ALBUM)+accept" \
         --bind="$KEYS_BROWSE:execute-silent:open \"https://musicbrainz.org/\track/{r3}\"" \
         --bind="$KEYS_OPEN:execute-silent:open \"\$(dirname {4})\"" \
+        --bind="$KEYS_N_YANK:execute-silent:printf {3} | $CLIP)" \
+        --bind="$KEYS_YANK_CURRENT:execute-silent:printf {2} | $CLIP" \
+        --bind="$KEYS_KEYBINDINGS:preview:$0 --show-keybindings $VIEW_PLAYLIST" \
+        --bind="$KEYS_SCROLL_PREVIEW_DOWN:preview-down" \
+        --bind="$KEYS_SCROLL_PREVIEW_UP:preview-up" \
+        --bind="$KEYS_PREVIEW_CLOSE:hide-preview" \
         --bind="$KEYS_PLAYBACK,$KEYS_N_PLAYBACK:transform($0 --playback $VIEW_PLAYLIST {2} {3} {4})+$FZF_RELOAD_PLAYLIST+$FZF_POS_PLAYLIST" \
         --bind="$KEYS_PLAYLIST_RELOAD:$FZF_RELOAD_PLAYLIST+$FZF_POS_PLAYLIST" \
         --bind="$KEYS_PLAYLIST_REMOVE:execute-silent($0 --playlist $PLAYLIST_CMD_REMOVE)+$FZF_RELOAD_PLAYLIST" \
@@ -565,6 +619,8 @@ while true; do
         --bind="$KEYS_PLAYLIST_CLEAR:execute-silent($0 --playlist $PLAYLIST_CMD_CLEAR)+$FZF_RELOAD_PLAYLIST" \
         --bind="$KEYS_PLAYLIST_CLEAR_ABOVE:execute-silent($0 --playlist $PLAYLIST_CMD_CLEAR_ABOVE)+$FZF_RELOAD_PLAYLIST" \
         --bind="$KEYS_PLAYLIST_CLEAR_BELOW:execute-silent($0 --playlist $PLAYLIST_CMD_CLEAR_BELOW)+$FZF_RELOAD_PLAYLIST" \
+        --bind="$KEYS_PLAYLIST_SHUFFLE:execute-silent($0 --playlist $PLAYLIST_CMD_SHUFFLE)+$FZF_RELOAD_PLAYLIST" \
+        --bind="$KEYS_PLAYLIST_UNSHUFFLE:execute-silent($0 --playlist $PLAYLIST_CMD_UNSHUFFLE)+$FZF_RELOAD_PLAYLIST" \
         --bind="$KEYS_PLAYLIST_GOTO_RELEASE:print($VIEW_RELEASE)+accept" \
         --delimiter="\t" \
         --with-nth="{1}" \
@@ -592,7 +648,7 @@ while true; do
     # `$PUT_FZF_KEY_LOGIC` for details.
     #
     # Here is a list of all keys grouped by type (see `src/sh/keys.sh`).
-    #--bind="start:change-border-label($VIEW)+change-list-label($MBID)+$MODE-input+transform:$0 --display" \
+    #--bind="start:change-list-label($VIEW)+change-list-label($MBID)+$MODE-input+transform:$0 --display" \
     sel=$(
       printf "" | $FZF \
         --reverse \
@@ -634,7 +690,7 @@ esac" \
         --bind="$KEYS_FILTER:transform:$0 --action-filter $FZF_CURRENT_MODE $FZF_CURRENT_VIEW" \
         --bind="$KEYS_BROWSE:execute-silent:
 [ {3} ] || exit 0
-case \$FZF_BORDER_LABEL in
+case $FZF_CURRENT_VIEW in
   $VIEW_LIST_ARTISTS | $VIEW_SEARCH_ARTIST) t=artist ;;
   $VIEW_ARTIST | $VIEW_SEARCH_ALBUM | $VIEW_LIST_ALBUMS) t=release-group ;;
   $VIEW_RELEASEGROUP) t=release ;;
@@ -644,14 +700,23 @@ open \"https://musicbrainz.org/\$t/{r3}\"" \
         --bind="$KEYS_OPEN:execute-silent:
 [ {4} ] || exit 0
 open \"\$(dirname {4})\"" \
+        --bind="$KEYS_N_YANK:transform:$IN_NORMAL_MODE && echo \"execute-silent(printf {3} | $CLIP)\" || $PUT_FZF_KEY_LOGIC" \
+        --bind="$KEYS_YANK_CURRENT:execute-silent:printf {2} | $CLIP" \
         --bind="$KEYS_SHOW_PLAYLIST:transform:echo \"print($VIEW_PLAYLIST)+print()+print($FZF_CURRENT_VIEW)+print({2})+accept\"" \
+        --bind="$KEYS_KEYBINDINGS:preview:$0 --show-keybindings $FZF_CURRENT_VIEW" \
+        --bind="$KEYS_REFRESH:execute-silent($0 --remove-from-cache $FZF_CURRENT_VIEW {2} {3})+transform:$0 --action-draw $FZF_CURRENT_MODE $FZF_CURRENT_VIEW {2}" \
         --bind="$KEYS_QUIT:print($VIEW_QUIT)+accept" \
         --bind="$KEYS_N_QUIT:transform:$IN_NORMAL_MODE && ($IN_LIST_ARTISTS_VIEW && echo \"print($VIEW_QUIT)+accept\" || $0 --action-draw $MODE_NORMAL $VIEW_LIST_ARTISTS) || $PUT_FZF_KEY_LOGIC" \
+        --bind="$KEYS_SCROLL_PREVIEW_DOWN:preview-down" \
+        --bind="$KEYS_SCROLL_PREVIEW_UP:preview-up" \
+        --bind="$KEYS_PREVIEW_OPEN:show-preview" \
+        --bind="$KEYS_PREVIEW_CLOSE:hide-preview" \
         --bind="$KEYS_PLAYBACK:transform:$0 --playback $FZF_CURRENT_VIEW {2} {3} {4}" \
         --bind="$KEYS_N_PLAYBACK:transform:$IN_NORMAL_MODE && $0 --playback $FZF_CURRENT_VIEW {2} {3} {4} || $PUT_FZF_KEY_LOGIC" \
+        --bind="W:execute-silent:echo 1 >> /tmp/foo; echo $FZF_CURRENT_VIEW >> /tmp/foo; echo 2 >> /tmp/foo" \
         --bind="change:execute-silent($0 --mbsearch $FZF_CURRENT_VIEW &)+reload:$0 --lines $FZF_CURRENT_VIEW" \
         --preview-window="right,25%,border-left,wrap,<30(hidden)" \
-        --preview="$0 --preview-artist {3}" \
+        --preview="$0 --preview $FZF_CURRENT_VIEW {3}" \
         --delimiter="\t" \
         --with-nth="{1}" || true
     )

src/sh/api.sh

@@ -1,8 +1,30 @@
-MB_MAX_RETRIES=10
-MB_BROWSE_STEPS=100
-USER_AGENT="$APP_NAME/$APP_VERSION ($APP_WEBSITE)"
-SLEEP_ON_ERROR=1
+# This file provides the methods for access to several APIs
+#
+# APIs:
+# - MusicBrainz
+# - Discogs
+# - Wikidata
+# - Wikipedia
+if [ ! "${API_LOADED:-}" ]; then
+  MB_MAX_RETRIES=10
+  MB_BROWSE_STEPS=100
+  USER_AGENT="$APP_NAME/$APP_VERSION ($APP_WEBSITE)"
+  SLEEP_ON_ERROR=1
+  export MB_MAX_RETRIES MB_BROWSE_STEPS USER_AGENT SLEEP_ON_ERROR
 
+  export API_LOADED=1
+fi
+
+# Internal method for MusicBrainz API access
+#
+# @argument $1: entity (see `case` below)
+# @argument $2: MusicBrainz ID
+# @argument $3: offset (optional, but mandatory for browse requests)
+#
+# If the API access fails, then the error message is logged, and at most
+# `MB_MAX_RETRIES` retries are made. If browse requests are made, then at most
+# `MB_BROWSE_STEPS` number of entries are requested per call. The offset in
+# browse request must be specified.
 __api_mb() {
   tmpout=$(mktemp)
   for _ in $(seq "$MB_MAX_RETRIES"); do
@@ -78,48 +100,79 @@ __api_mb() {
         "https://musicbrainz.org/ws/2/release-group"
       ;;
     esac
-    if ! $JQ -e '.error' "$tmpout" >/dev/null 2>/dev/stdout; then
+    errormsg=$($JQ -e '.error // ""' "$tmpout")
+    if [ "$errormsg" ]; then
+      err "Failed to fetch MusicBrainz data for $1 $2: $errormsg"
+      echo "$errormsg" | grep -q -i "not found" && break
+      echo "$errormsg" | grep -q -i "invalid" && break
+      sleep "$SLEEP_ON_ERROR"
+    else
       cat "$tmpout"
       rm -f "$tmpout"
       return 0
-    else
-      sleep "$SLEEP_ON_ERROR"
     fi
   done
   rm -f "$tmpout"
-  err "Failed to fetch MusicBrainz data for $1 $2"
+  err "Failed to fetch MusicBrainz data for $1 $2 (not retrying anymore...)"
   return 1
 }
 
+# The interface to MusicBrainz API.
+
+# Retrieve MusicBrainz artist information
+#
+# @argument $1: MusicBrainz artist ID
 api_mb_artist() {
   __api_mb "artist" "$1"
 }
 
+# Retrieve MusicBrainz release-group information
+#
+# @argument $1: MusicBrainz release-group ID
 api_mb_releasegroup() {
   __api_mb "releasegroup" "$1"
 }
 
+# Retrieve MusicBrainz release information
+#
+# @argument $1: MusicBrainz release ID
 api_mb_release() {
   __api_mb "release" "$1"
 }
 
+# Retrieve MusicBrainz release-groups for given artist
+#
+# @argument $1: MusicBrainz artist ID
+# @argument $2: offset (defaults to 0)
 api_mb_browse_artist_releasegroups() {
   __api_mb "browse-artist-releasegroups" "$1" "${2:-0}"
 }
 
+# Retrieve MusicBrainz releases in given release group
+#
+# @argument $1: MusicBrainz release-group ID
+# @argument $2: offset (defaults to 0)
 api_mb_browse_releasegroup_releases() {
   __api_mb "browse-releasegroup-releases" "$1" "${2:-0}"
 }
 
-# Argument: Search string
+# Search MusicBrainz database for given artist
+#
+# @argument $1: query
 api_mb_search_artist() {
   __api_mb "search-artist" "$1"
 }
 
+# Search MusicBrainz database for given release group
+#
+# @argument $1: query
 api_mb_search_releasegroup() {
   __api_mb "search-releasegroup" "$1"
 }
 
+# Retrieve Discogs artist information
+#
+# @argument $1: Discogs artist ID
 api_discogs_artist() {
   $CURL \
     --get \
@@ -127,6 +180,9 @@ api_discogs_artist() {
     "https://api.discogs.com/artists/$1"
 }
 
+# Retrieve sitelinks from wikidata
+#
+# @argument $1: Wikidata ID
 api_wikidata_sitelinks() {
   $CURL \
     --get \
@@ -134,6 +190,9 @@ api_wikidata_sitelinks() {
     "https://www.wikidata.org/w/rest.php/wikibase/v1/entities/items/$1/sitelinks"
 }
 
+# Retrieve summary from Wikipedia page
+#
+# @argument $1: Wikipedia page name
 api_wikipedia_en_summary() {
   $CURL \
     --get \

src/sh/awk.sh

@@ -1,3 +1,5 @@
+# The code below is used together with `scripts/build.sh`to internalize the awk
+# scripts. See the awk sources for more information.
 if [ ! "${AWK_LOADED:-}" ]; then
   AWK_ARTISTS=$(
     cat <<'EOF'

src/sh/cache.sh

@@ -1,31 +1,59 @@
-# Caching structure
+# This implements the caching functionalities. The cache is stored under
+# `CACHEDIR` defined below, and organized as follows (all paths relative to
+# `CAHCEDIR`) ./<type>/radix(mbid)/<file>. Here, type is one of `TYPE_ARTIST`,
+# `TYPE_RELEASEGROUP`, or `TYPE_RELEASE`. The string `radix(mbid)` is the radix
+# encoded MusicBrainz ID of given type (see method below). Finally <file> is a
+# filename to hold the respective data in the json format. Currently, the data
+# is stored as follows:
+# ./artist/radix(mbid)/musicbrainz.json         MusicBrainz artist data
+# ./artist/radix(mbid)/discogs.json             Discogs artist data
+# ./artist/radix(mbid)/wikidata.json            Wikidata artist data
+# ./artist/radix(mbid)/enwikipedia.json         Wikipedia artist data
+# ./artist/radix(mbid)/releasegroups.json       Release groups of artist
+# ./releasegroup/radix(mbid)/musicbrainz.json   MusicBrainz release-group data
+# ./releasegroup/radix(mbid)/releases.json      Releases in release group
+# ./release/radix(mbid)/musicbrainz.json        MusicBrainz release data
+
+if [ ! "${CACHE_LOADED:-}" ]; then
+  # Base path for cache
+  CACHEDIR="$HOME/.cache/$APP_NAME"
+  # Directory names for cache types
+  TYPE_ARTIST="artist"
+  TYPE_RELEASEGROUP="releasegroup"
+  TYPE_RELEASE="release"
+  # Filenames for cache entries
+  ARTIST_FILENAME="musicbrainz.json"
+  ARTIST_RELEASEROUPS_FILENAME="releasegroups.json"
+  ARTIST_DISCOGS_FILENAME="discogs.json"
+  ARTIST_WIKIDATA_FILENAME="wikidata.json"
+  ARTIST_ENWIKIPEDIA_FILENAME="enwikipedia.json"
+  RELEASEGROUP_FILENAME="musicbrainz.json"
+  RELEASEGROUP_RELEASES_FILENAME="releases.json"
+  RELEASE_FILENAME="musicbrainz.json"
+  export CACHEDIR TYPE_ARTIST TYPE_RELEASEGROUP TYPE_RELEASE ARTIST_FILENAME \
+    ARTIST_RELEASEROUPS_FILENAME ARTIST_DISCOGS_FILENAME \
+    ARTIST_WIKIDATA_FILENAME ARTIST_ENWIKIPEDIA_FILENAME \
+    RELEASEGROUP_FILENAME RELEASEGROUP_RELEASES_FILENAME RELEASE_FILENAME
+
+  export CACHE_LOADED=1
+fi
+
+# Radix transform string
 #
-# ./artist/radix(uuid)/musicbrainz.json         # Artist information
-# ./artist/radix(uuid)/releasegroups.json       # List of all release groups
-# ./artist/radix(uuid)/...                      # Any other artist information
-# ./releasegroup/radix(uuid)/musicbrainz.json   # Release group information
-# ./releasegroup/radix(uuid)/releases.json      # List of all releases in release group
-# ./release/radix(uuid)/musicbrainz.json        # Release information with tracklist etc.
-CACHEDIR="$HOME/.cache/$APP_NAME"
-TYPE_ARTIST="artist"
-TYPE_RELEASEGROUP="releasegroup"
-TYPE_RELEASE="release"
-
-artist_filename="musicbrainz.json"
-artist_releasegroups_filename="releasegroups.json"
-artist_discogs_filename="discogs.json"
-artist_wikidata_filename="wikidata.json"
-artist_enwikipedia_filename="enwikipedia.json"
-releasegroup_filename="musicbrainz.json"
-releasegroup_releases_filename="releases.json"
-release_filename="musicbrainz.json"
-
-# Radix transform directory name
+# @argument $1: some string
 __radix() {
   echo "$1" | awk -F "" '{ print $1$2$3$4"/"$5$6$7$8"/"$0 }'
 }
 
-# Super wrapper
+# Radix transform strings (batch)
+#
+# Here, the input is read line-by-line from stdin.
+__radix_batch() {
+  cat | awk -F "" '{ print $1$2$3$4"/"$5$6$7$8"/"$0 }'
+}
+
+# Super wrapper to print json data from cache
+#
 # argument $1: type
 # argument $2: MusicBrainz ID
 # argument $3: Filename of json file
@@ -35,7 +63,8 @@ __get_json() {
   cat "$f"
 }
 
-# Super wrapper
+# Super wrapper to store json data in cache
+#
 # argument $1: type
 # argument $2: MusicBrainz ID
 # argument $3: Filename of json file
@@ -48,114 +77,221 @@ __put_json() {
   [ -s "$tmpf" ] && mv "$tmpf" "$f" || printf "{}" >"$f"
 }
 
-## Artist
+# Print MusicBrainz data of given artist from cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_get_artist() {
-  __get_json "$TYPE_ARTIST" "$1" "$artist_filename"
+  __get_json "$TYPE_ARTIST" "$1" "$ARTIST_FILENAME"
 }
 
+# Print release groups (MusicBrainz) of given artist from cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_get_artist_releasegroups() {
-  __get_json "$TYPE_ARTIST" "$1" "$artist_releasegroups_filename"
+  __get_json "$TYPE_ARTIST" "$1" "$ARTIST_RELEASEROUPS_FILENAME"
 }
 
+# Print Discogs data of given artist from cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_get_artist_discogs() {
-  __get_json "$TYPE_ARTIST" "$1" "$artist_discogs_filename"
+  __get_json "$TYPE_ARTIST" "$1" "$ARTIST_DISCOGS_FILENAME"
 }
 
+# Print Wikipedia data of given artist from cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_get_artist_enwikipedia() {
-  __get_json "$TYPE_ARTIST" "$1" "$artist_enwikipedia_filename"
+  __get_json "$TYPE_ARTIST" "$1" "$ARTIST_ENWIKIPEDIA_FILENAME"
 }
 
+# Print Wikidata data of given artist from cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_get_artist_wikidata() {
-  __get_json "$TYPE_ARTIST" "$1" "$artist_wikidata_filename"
+  __get_json "$TYPE_ARTIST" "$1" "$ARTIST_WIKIDATA_FILENAME"
 }
 
+# Store MusicBrainz data of given artist in cache
+#
+# @argument $1: MusicBrainz artist ID
+#
+# This methods reads the data to be stored from stdin.
 cache_put_artist() {
-  cat | __put_json "$TYPE_ARTIST" "$1" "$artist_filename"
+  cat | __put_json "$TYPE_ARTIST" "$1" "$ARTIST_FILENAME"
 }
 
+# Store release groups (MusicBrainz) of given artist in cache
+#
+# @argument $1: MusicBrainz artist ID
+#
+# This methods reads the data to be stored from stdin.
 cache_put_artist_releasegroups() {
-  cat | __put_json "$TYPE_ARTIST" "$1" "$artist_releasegroups_filename"
+  cat | __put_json "$TYPE_ARTIST" "$1" "$ARTIST_RELEASEROUPS_FILENAME"
 }
 
+# Append release groups (MusicBrainz) of given artist to existing file in cache
+#
+# @argument $1: MusicBrainz artist ID
+#
+# This methods reads the data to be stored from stdin.
 cache_append_artist_releasegroups() {
   tmpf=$(mktemp)
   cat >"$tmpf"
   updated=$(mktemp)
-  f="$CACHEDIR/$TYPE_ARTIST/$(__radix "$1")/$artist_releasegroups_filename"
+  f="$CACHEDIR/$TYPE_ARTIST/$(__radix "$1")/$ARTIST_RELEASEROUPS_FILENAME"
   $JQ --slurpfile n "$tmpf" '."release-groups" += ($n[0]|."release-groups")' "$f" >"$updated" && mv "$updated" "$f"
   rm -f "$tmpf"
 }
 
+# Store Discogs data of given artist to cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_put_artist_discogs() {
-  cat | __put_json "$TYPE_ARTIST" "$1" "$artist_discogs_filename"
+  cat | __put_json "$TYPE_ARTIST" "$1" "$ARTIST_DISCOGS_FILENAME"
 }
 
+# Store Wikipedia data of given artist to cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_put_artist_enwikipedia() {
-  cat | __put_json "$TYPE_ARTIST" "$1" "$artist_enwikipedia_filename"
+  cat | __put_json "$TYPE_ARTIST" "$1" "$ARTIST_ENWIKIPEDIA_FILENAME"
 }
 
+# Store Wikidata data of given artist to cache
+#
+# @argument $1: MusicBrainz artist ID
 cache_put_artist_wikidata() {
-  cat | __put_json "$TYPE_ARTIST" "$1" "$artist_wikidata_filename"
+  cat | __put_json "$TYPE_ARTIST" "$1" "$ARTIST_WIKIDATA_FILENAME"
 }
 
-## Release group
+# Print MusicBrainz data of given release group from cache
+#
+# @argument $1: MusicBrainz release-group ID
 cache_get_releasegroup() {
-  __get_json "$TYPE_RELEASEGROUP" "$1" "$releasegroup_filename"
+  __get_json "$TYPE_RELEASEGROUP" "$1" "$RELEASEGROUP_FILENAME"
 }
 
+# Print releases (MusicBrainz) in release group from cache
+#
+# @argument $1: MusicBrainz release-group ID
 cache_get_releasegroup_releases() {
-  __get_json "$TYPE_RELEASEGROUP" "$1" "$releasegroup_releases_filename"
+  __get_json "$TYPE_RELEASEGROUP" "$1" "$RELEASEGROUP_RELEASES_FILENAME"
 }
 
+# Store MusicBrainz data of given release group in cache
+#
+# @argument $1: MusicBrainz release-group ID
 cache_put_releasegroup() {
-  cat | __put_json "$TYPE_RELEASEGROUP" "$1" "$releasegroup_filename"
+  cat | __put_json "$TYPE_RELEASEGROUP" "$1" "$RELEASEGROUP_FILENAME"
 }
 
+# Store releases (MusicBrainz) of given release group in cache
+#
+# @argument $1: MusicBrainz release-group ID
 cache_put_releasegroup_releases() {
-  cat | __put_json "$TYPE_RELEASEGROUP" "$1" "$releasegroup_releases_filename"
+  cat | __put_json "$TYPE_RELEASEGROUP" "$1" "$RELEASEGROUP_RELEASES_FILENAME"
 }
 
+# Append releases (MusicBrainz) of given release group to existing file in
+# cache
+#
+# @argument $1: MusicBrainz release-group ID
 cache_append_releasegroup_releases() {
   tmpf=$(mktemp)
   cat >"$tmpf"
   updated=$(mktemp)
-  f="$CACHEDIR/$TYPE_RELEASEGROUP/$(__radix "$1")/$releasegroup_releases_filename"
+  f="$CACHEDIR/$TYPE_RELEASEGROUP/$(__radix "$1")/$RELEASEGROUP_RELEASES_FILENAME"
   $JQ --slurpfile n "$tmpf" '."releases" += ($n[0]|."releases")' "$f" >"$updated" && mv "$updated" "$f"
   rm -f "$tmpf"
 }
 
-## Release
+# Print MusicBrainz data of given release from cache
+#
+# @argument $1: MusicBrainz release ID
 cache_get_release() {
-  __get_json "$TYPE_RELEASE" "$1" "$release_filename"
+  __get_json "$TYPE_RELEASE" "$1" "$RELEASE_FILENAME"
 }
 
+# Store MusicBrainz data of given release in cache
+#
+# @argument $1: MusicBrainz release ID
 cache_put_release() {
-  cat | __put_json "$TYPE_RELEASE" "$1" "$release_filename"
+  cat | __put_json "$TYPE_RELEASE" "$1" "$RELEASE_FILENAME"
 }
 
-## Cache deletion
-cache_delete_artist() {
-  # Get release groups
-  echo "NOT IMPLEMENTED" >/dev/stderr
-}
-
-# Check if main items are in cache
-# argument $1: type
-# argument $2: MusicBrainz ID
-in_cache() {
+# Print all MusicBrainz cache paths to the files specified by their IDs
+#
+# @argument $1: type
+#
+# This method reads from stdin any number of MusicBrainz IDs of objects of the
+# specified type, and prints the file paths.
+cache_get_file_batch() {
   case "$1" in
-  "$TYPE_ARTIST")
-    fn="$artist_filename"
-    ;;
-  "$TYPE_RELEASEGROUP")
-    fn="$releasegroup_filename"
-    ;;
-  "$TYPE_RELEASE")
-    fn="$release_filename"
-    ;;
-  *)
-    return 1
-    ;;
+  "$TYPE_ARTIST") fn="$ARTIST_FILENAME" ;;
+  "$TYPE_RELEASEGROUP") fn="$RELEASEGROUP_FILENAME" ;;
+  "$TYPE_RELEASE") fn="$RELEASE_FILENAME" ;;
+  *) return 1 ;;
   esac
-  [ "$(__get_json "$1" "$2" "$fn")" ] && return 0 || return 1
+  cat |
+    __radix_batch |
+    awk -v dir="$CACHEDIR/$1/" -v f="/$fn" '{ print dir $0 f }'
+}
+
+# Print MusicBrainz ID associated to the file paths
+#
+# This reads from stdin any number of paths (one per line)
+cache_mbid_from_path_batch() {
+  cat | awk -F "/" '{ print $(NF-1) }'
+}
+
+# Remove artist items from cache
+#
+# @argument $1: MusicBrainz arist ID
+#
+# This function is "safer" than other because it removes data. These safty
+# checks are paranoid.
+cache_rm_artist() {
+  [ "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR/$TYPE_ARTIST" ] || return 1
+  d="$CACHEDIR/$TYPE_ARTIST/$(__radix "$1")/"
+  [ "$d" ] || return 1
+  [ -d "$d" ] || return 1
+  info "removing $d"
+  rm -rf "$d"
+}
+
+# Remove release-group items from cache
+#
+# @argument $1: MusicBrainz release-group ID
+#
+# This function is "safer" than other because it removes data. These safty
+# checks are paranoid.
+cache_rm_releasegroup() {
+  [ "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR/$TYPE_RELEASEGROUP" ] || return 1
+  d="$CACHEDIR/$TYPE_RELEASEGROUP/$(__radix "$1")/"
+  [ "$d" ] || return 1
+  [ -d "$d" ] || return 1
+  info "removing $d"
+  rm -rf "$d"
+}
+
+# Remove release items from cache
+#
+# @argument $1: MusicBrainz release ID
+#
+# This function is "safer" than other because it removes data. These safty
+# checks are paranoid.
+cache_rm_release() {
+  [ "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR" ] || return 1
+  [ -d "$CACHEDIR/$TYPE_RELEASE" ] || return 1
+  d="$CACHEDIR/$TYPE_RELEASE/$(__radix "$1")/"
+  [ "$d" ] || return 1
+  [ -d "$d" ] || return 1
+  info "removing $d"
+  rm -rf "$d"
 }

src/sh/config.sh

@@ -1,4 +1,16 @@
-# Configuration capabilities
+# Main application configuration. This application does not require a
+# configuration file. However, a configuration file may be stored as
+# `CONFIGFILE_DEFAULT`. If that file exists, it will be sourced. The path to
+# the file may be overwritten by specifying the environment variable
+# `CONFIGFILE`. If a configuration file is specified, then it must also exist.
+# A configuration file comprises the specification of environment variables
+# that are` allowed to be set.
+#
+# Currently, the following files hold variables that are configurable:
+# - `src/sh/filter.sh`:  Configuration of filters that can be triggered with
+#                        the respective key bindings.
+# - `src/sh/keys.sh`:    Configuration of key bindings to certain actions
+# - `src/sh/theme.sh`:   Configuration of theme
 CONFIGFILE_DEFAULT="$HOME/.config/$APP_NAME/config"
 CONFIGFILE="${CONFIGFILE:-"$CONFIGFILE_DEFAULT"}"
 [ "$CONFIGFILE" != "$CONFIGFILE_DEFAULT" ] && [ ! -f "$CONFIGFILE" ] && err "The configuration file manually specified with the environment variable CONFIGFILE=($CONFIGFILE) does not exist." && exit 1

src/sh/filter.sh

@@ -1,7 +1,14 @@
-# Preset filters
-#
-# See `src/sh/query.sh` for details and the associated methods.
+# Preset filters for different views. These filters are associated to key
+# bindings (see `src/sh/keys.sh`), and are configurable through a configuration
+# file (see `src/sh/config.sh`).
+
+# The `QUERY_LOCAL` filter is associated with the keys `KEYS_FILTER_LOCAL`. It
+# is used to hide all entries that are not available locally (see
+# `src/sh/query.sh` for details and the relevant methods)
 QUERY_LOCAL="${QUERY_LOCAL:-"$(printf "'%s'" "$FORMAT_LOCAL" | __clean_filter)"}"
+
+# The following variables store preset strings derived from the theme (see
+# `src/sh/theme.sh`), and used in the assignment of the default filters.
 q_has_seconary="$(printf "$FORMAT_TYPE_HAS_SECONDARY" "" | __clean_filter)"
 q_album="$(printf "%s" "$FORMAT_TYPE_ALBUM" | __clean_filter)"
 q_ep=$(printf "%s" "$FORMAT_TYPE_EP" | sed "s/${ESC}\[[0-9;]*[mK]//g" | sed "s/ /\\\ /g")
@@ -11,6 +18,9 @@ if printf "$RV_FORMAT" | grep -q "<<status>>"; then
 fi
 export QUERY_LOCAL
 
+# Here starts the list of all filters (grouped per view) that are associated to
+# the keys `KEYS_FILTER_0` - `KEYS_FILTER_9`. The filters in the `F_1_<view>`
+# variable are automatically applied whenever the given view is entered.
 F_1_VIEW_ARTIST="${F_1_VIEW_ARTIST:-"!'$q_has_seconary'"}"
 F_2_VIEW_ARTIST="${F_2_VIEW_ARTIST:-"'$q_album'"}"
 F_3_VIEW_ARTIST="${F_3_VIEW_ARTIST:-"'$q_ep'"}"

src/sh/fzf.sh

@@ -1,4 +1,5 @@
-# Print the command that sets the header.
+# Print the fzf instructions that sets the header
+#
 # @argument $1: view
 # @argument $2: mbid
 fzf_command_set_header() {
@@ -11,112 +12,39 @@ fzf_command_set_header() {
   "$VIEW_LIST_ALBUMS") header="Search locally available album" ;;
   "$VIEW_ARTIST")
     name="$(mb_artist "$mbid" | $JQ '.name')"
-    header=$(printf "$ARTIST_PROMPT" "$name")
+    header=$(printf "$HEADER_ARTIST" "$name")
     ;;
   "$VIEW_RELEASEGROUP")
     title="$(mb_releasegroup "$mbid" |
       $JQ '.title')"
     artist="$(mb_releasegroup "$mbid" |
       $JQ '."artist-credit" | map(([.name, .joinphrase]|join(""))) | join("")')"
-    header=$(printf "$FULL_PROMPT" "$artist" "$title")
+    header=$(printf "$HEADER_ARTIST_RELEASEGROUP" "$artist" "$title")
     ;;
   "$VIEW_RELEASE")
     title="$(mb_release "$mbid" |
       $JQ '.title')"
     artist="$(mb_release "$mbid" |
       $JQ '."artist-credit" | map(([.name, .joinphrase]|join(""))) | join("")')"
-    header=$(printf "$FULL_PROMPT" "$artist" "$title")
+    releaseinfo="$(mb_release "$mbid" |
+      $JQ '[
+    .date[:4],
+    (."label-info" | map(.label.name) | unique | join(", ")),
+    (.media | map(."track-count") | add),
+    (.media | map(.format) | unique | join(", ")),
+    .country
+    ] | join("\t")' |
+      awk -F "\t" -v format="$HEADER_RELEASE_FORMAT" '{
+        gsub("&", "\\\\&")
+        sub("<<year>>", $1, format)
+        sub("<<label>>", $2, format)
+        sub("<<tracks>>", $3, format)
+        sub("<<media>>", $4, format)
+        sub("<<country>>", $5, format)
+        print format
+      }')"
+    header=$(printf "$HEADER_RELEASE" "$artist" "$title" "$releaseinfo")
     ;;
   esac
   printf "+change-header(%s)" "${header:-"???"}"
 }
-
-# Reload hook that is used after change in query
-fzf_reload_after_change() {
-  # Wait for async. process to terminate
-  sleep 1
-  while [ -f "$LOCKFILE" ]; do
-    sleep 1
-  done
-  # Show results
-  column -t -s "$(printf '\t')" "$RESULTS" |
-    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|'
-}
-
-# Handle change in query
-fzf_handle_change() {
-  view="$1"
-  # Kill any running search
-  if [ -f "$PIDFILE" ]; then
-    pid=$(cat "$PIDFILE")
-    rm -f "$PIDFILE"
-    kill -9 "$pid" >/dev/null 2>&1 || true
-  fi
-  # Stop, if no search string is given
-  [ "$FZF_QUERY" ] || exit 0
-  # Store PID of current process
-  echo "$$" >"$PIDFILE"
-  touch "$LOCKFILE"
-  sleep 1
-  if [ "$view" = "$VIEW_SEARCH_ARTIST" ]; then
-    api_mb_search_artist "$FZF_QUERY" |
-      $JQ '.artists[] | [
-    .id,
-    .type,
-    .name,
-    .disambiguation,
-    .["life-span"].begin,
-    .["life-span"].end
-    ] | join("\t")' |
-      awk \
-        -F "\t" \
-        -v file_local_artists="${LOCALDATA_ARTISTS:-}" \
-        -v format_person="$AV_PERSON" \
-        -v format_group="$AV_GROUP" \
-        -v format_disambiguation="$AV_DISAMBIGUATION" \
-        -v format_local="$FORMAT_LOCAL" \
-        "$AWK_ARTISTS" >"$RESULTS" ||
-      true
-  else
-    api_mb_search_releasegroup "$FZF_QUERY" |
-      $JQ '."release-groups"[] | [ 
-    .id,
-    ."primary-type",
-    (."secondary-types" // []|join(";")),
-    ."first-release-date",
-    .title,
-    (."artist-credit" | map(([.name, .joinphrase]|join(""))) | join(""))
-    ] | join("\t")' |
-      awk \
-        -F "\t" \
-        -v file_local_releasegroups="${LOCALDATA_RELEASEGROUPS:-}" \
-        -v format_release="$RGV_RELEASE" \
-        -v format_release_w_artist="$RGV_RELEASE_W_ARTIST" \
-        -v format_year="$RGV_YEAR" \
-        -v format_album="$FORMAT_TYPE_ALBUM" \
-        -v format_single="$FORMAT_TYPE_SINGLE" \
-        -v format_ep="$FORMAT_TYPE_EP" \
-        -v format_broadcast="$FORMAT_TYPE_BROADCAST" \
-        -v format_other="$FORMAT_TYPE_OTHER" \
-        -v format_has_secondary="$FORMAT_TYPE_HAS_SECONDARY" \
-        -v format_secondary="$FORMAT_TYPE_SECONDARY" \
-        -v format_compilation="$FORMAT_TYPE_SECONDARY_COMPILATION" \
-        -v format_soundtrack="$FORMAT_TYPE_SECONDARY_SOUNDTRACK" \
-        -v format_spokenword="$FORMAT_TYPE_SECONDARY_SPOKENWORD" \
-        -v format_interview="$FORMAT_TYPE_SECONDARY_INTERVIEW" \
-        -v format_audiobook="$FORMAT_TYPE_SECONDARY_AUDIOBOOK" \
-        -v format_audiodrama="$FORMAT_TYPE_SECONDARY_AUDIODRAMA" \
-        -v format_live="$FORMAT_TYPE_SECONDARY_LIVE" \
-        -v format_remix="$FORMAT_TYPE_SECONDARY_REMIX" \
-        -v format_djmix="$FORMAT_TYPE_SECONDARY_DJMIX" \
-        -v format_mixtape="$FORMAT_TYPE_SECONDARY_MIXTAPE" \
-        -v format_demo="$FORMAT_TYPE_SECONDARY_DEMO" \
-        -v format_fieldrec="$FORMAT_TYPE_SECONDARY_FIELDREC" \
-        -v format_local="$FORMAT_LOCAL" \
-        "$AWK_RELEASEGROUPS" |
-      cut -d "$(printf '\t')" -f 2- >"$RESULTS" ||
-      true
-  fi
-  # Process ends now: Display and quit
-  rm -f "$LOCKFILE" "$PIDFILE"
-}

src/sh/info.sh

@@ -1,5 +1,10 @@
 # Application information
-APP_NAME="muf"
-APP_VERSION="zero.zero"
-APP_WEBSITE="https://git.indyfac.ch/amin/muf"
-WINDOW_TITLE="🔎🎶 $APP_NAME | a simple music finder and player"
+if [ ! "${INFO_LOADED:-}" ]; then
+  APP_NAME="fuzic"
+  APP_VERSION="0.1"
+  APP_WEBSITE="https://git.indyfac.ch/amin/fuzic"
+  WINDOW_TITLE="🔎🎶 $APP_NAME | a simple music finder and player"
+  export APP_NAME APP_VERSION APP_WEBSITE WINDOW_TITLE
+
+  export INFO_LOADED=1
+fi

src/sh/keys.sh

@@ -48,10 +48,18 @@
 # Specials:
 # - KEYS_BROWSE: Open MusicBrainz webpage of the selected item
 # - KEYS_OPEN: Open file manager in the directory of the selected item
+# - KEYS_N_YANK: Copy MusicBrainz ID of selected item to clipboard
+# - KEYS_YANK_CURRENT: Copy MusicBrainz ID of current item to clipboard
 # - KEYS_SHOW_PLAYLIST: Switch to playlist view
+# - KEYS_KEYBINDINGS: Show keybindings
 # - KEYS_QUIT: Quit application
 # - KEYS_N_QUIT: Quit application if we are in VIEW_LIST_ARTISTS, else go to
 # view VIEW_LIST_ARTISTS (normal mode)
+# - KEYS_SCROLL_PREVIEW_DOWN: Scroll preview down
+# - KEYS_SCROLL_PREVIEW_UP: Scroll preview up
+# - KEYS_PREVIEW_OPEN: Open preview window
+# - KEYS_PREVIEW_CLOSE: Close preview window
+# - KEYS_REFRESH: Refresh current entry
 #
 # Playback:
 # - KEYS_PLAY: Play selected release or selected track
@@ -72,107 +80,301 @@
 # - KEYS_PLAYLIST_CLEAR: Clear playlist
 # - KEYS_PLAYLIST_CLEAR_ABOVE: Remove all items above incl. the selected one
 # - KEYS_PLAYLIST_CLEAR_BELOW: Remove all items below incl. the selected one
-# - KEYS_PLAYLIST_GOTO_RELEASE: Jump to release or seleted enry
+# - KEYS_PLAYLIST_SHUFFLE: Shuffle playlist
+# - KEYS_PLAYLIST_UNSHUFFLE: Unshuffle previously shuffled playlist
+# - KEYS_PLAYLIST_GOTO_RELEASE: Jump to release or selected entry
 # - KEYS_PLAYLIST_STORE: Store current playlist as file
 # - KEYS_PLAYLIST_LOAD: Load playlist from file
 # - KEYS_PLAYLIST_QUIT: Quit playlist view
+
+if [ ! "${KEYS_LOADED:-}" ]; then
+  # Mode selection:
+  KEYS_I_NORMAL="${KEYS_I_NORMAL:-"esc"}"
+  KEYS_N_INSERT="${KEYS_N_INSERT:-"a,i,/,?"}"
+  export KEYS_I_NORMAL KEYS_N_INSERT
+
+  # Vertical navigation:
+  KEYS_DOWN="${KEYS_DOWN:-"ctrl-j,down"}"
+  KEYS_UP="${KEYS_UP:-"ctrl-k,up"}"
+  KEYS_HALFPAGE_DOWN="${KEYS_HALFPAGE_DOWN:-"ctrl-d"}"
+  KEYS_HALFPAGE_UP="${KEYS_HALFPAGE_UP:-"ctrl-u"}"
+  KEYS_N_DOWN="${KEYS_N_DOWN:-"j"}"
+  KEYS_N_UP="${KEYS_N_UP:-"k"}"
+  KEYS_N_BOT="${KEYS_N_BOT:-"G"}"
+  KEYS_N_TOP="${KEYS_N_TOP:-"1"}"
+  export KEYS_DOWN KEYS_UP KEYS_HALFPAGE_DOWN KEYS_HALFPAGE_UP KEYS_N_DOWN \
+    KEYS_N_UP KEYS_N_BOT KEYS_N_TOP
+
+  # Horizontal navigation:
+  KEYS_IN="${KEYS_IN:-"ctrl-l"}"
+  KEYS_OUT="${KEYS_OUT:-"ctrl-h"}"
+  KEYS_N_IN="${KEYS_N_IN:-"l"}"
+  KEYS_N_OUT="${KEYS_N_OUT:-"h"}"
+  KEYS_SELECT_ARTIST="${KEYS_SELECT_ARTIST:-"ctrl-a"}"
+  KEYS_LIST_ARTISTS="${KEYS_LIST_ARTISTS:-"alt-a"}"
+  KEYS_LIST_ALBUMS="${KEYS_LIST_ALBUMS:-"alt-s"}"
+  KEYS_SEARCH_ARTIST="${KEYS_SEARCH_ARTIST:-"alt-z"}"
+  KEYS_SEARCH_ALBUM="${KEYS_SEARCH_ALBUM:-"alt-x"}"
+  KEYS_SWITCH_ARTIST_ALBUM="${KEYS_SWITCH_ARTIST_ALBUM:-"tab"}"
+  KEYS_SWITCH_LOCAL_REMOTE="${KEYS_SWITCH_LOCAL_REMOTE:-"ctrl-/"}"
+  export KEYS_IN KEYS_OUT KEYS_N_IN KEYS_N_OUT KEYS_SELECT_ARTIST \
+    KEYS_LIST_ARTISTS KEYS_LIST_ALBUMS KEYS_SEARCH_ARTIST KEYS_SEARCH_ALBUM \
+    KEYS_SWITCH_ARTIST_ALBUM KEYS_SWITCH_LOCAL_REMOTE
+
+  # Filtering:
+  KEYS_FILTER_LOCAL="${KEYS_FILTER_LOCAL:-"alt-l"}"
+  KEYS_FILTER_1="${KEYS_FILTER_1:-"alt-1"}"
+  KEYS_FILTER_2="${KEYS_FILTER_2:-"alt-2"}"
+  KEYS_FILTER_3="${KEYS_FILTER_3:-"alt-3"}"
+  KEYS_FILTER_4="${KEYS_FILTER_4:-"alt-4"}"
+  KEYS_FILTER_5="${KEYS_FILTER_5:-"alt-5"}"
+  KEYS_FILTER_6="${KEYS_FILTER_6:-"alt-6"}"
+  KEYS_FILTER_7="${KEYS_FILTER_7:-"alt-7"}"
+  KEYS_FILTER_8="${KEYS_FILTER_8:-"alt-8"}"
+  KEYS_FILTER_9="${KEYS_FILTER_9:-"alt-9"}"
+  KEYS_FILTER_0="${KEYS_FILTER_0:-"alt-0"}"
+  KEYS_FILTER="$KEYS_FILTER_LOCAL,$KEYS_FILTER_1,$KEYS_FILTER_2,$KEYS_FILTER_3,$KEYS_FILTER_4,$KEYS_FILTER_5,$KEYS_FILTER_6,$KEYS_FILTER_7,$KEYS_FILTER_8,$KEYS_FILTER_9,$KEYS_FILTER_0"
+  export KEYS_FILTER_LOCAL KEYS_FILTER_1 KEYS_FILTER_2 KEYS_FILTER_3 \
+    KEYS_FILTER_4 KEYS_FILTER_5 KEYS_FILTER_6 KEYS_FILTER_7 KEYS_FILTER_8 \
+    KEYS_FILTER_9 KEYS_FILTER_0 KEYS_FILTER
+
+  # Specials:
+  KEYS_BROWSE="${KEYS_BROWSE:-"alt-b"}"
+  KEYS_OPEN="${KEYS_OPEN:-"alt-o"}"
+  KEYS_N_YANK="${KEYS_N_YANK:-"y"}"
+  KEYS_YANK_CURRENT="${KEYS_YANK_CURRENT:-"ctrl-y"}"
+  KEYS_SHOW_PLAYLIST="${KEYS_SHOW_PLAYLIST:-"ctrl-p"}"
+  KEYS_KEYBINDINGS="${KEYS_KEYBINDINGS:-"alt-?"}"
+  KEYS_QUIT="${KEYS_QUIT:-"ctrl-c"}"
+  KEYS_N_QUIT="${KEYS_N_QUIT:-"q"}"
+  KEYS_SCROLL_PREVIEW_DOWN="${KEYS_SCROLL_PREVIEW_DOWN:-"page-down"}"
+  KEYS_SCROLL_PREVIEW_UP="${KEYS_SCROLL_PREVIEW_UP:-"page-up"}"
+  KEYS_PREVIEW_OPEN="${KEYS_PREVIEW_OPEN:-"alt-up"}"
+  KEYS_PREVIEW_CLOSE="${KEYS_PREVIEW_CLOSE:-"alt-down"}"
+  KEYS_REFRESH="${KEYS_REFRESH:-"ctrl-r"}"
+  export KEYS_BROWSE KEYS_OPEN KEYS_N_YANK KEYS_YANK_CURRENT KEYS_SHOW_PLAYLIST \
+    KEYS_KEYBINDINGS KEYS_QUIT KEYS_N_QUIT KEYS_SCROLL_PREVIEW_DOWN \
+    KEYS_SCROLL_PREVIEW_UP KEYS_PREVIEW_CLOSE KEYS_PREVIEW_OPEN KEYS_REFRESH
+
+  # Playback:
+  KEYS_PLAY="${KEYS_PLAY:-"enter"}"
+  KEYS_QUEUE="${KEYS_QUEUE:-"ctrl-alt-m"}" # That's actually alt-enter
+  KEYS_QUEUE_NEXT="${KEYS_QUEUE_NEXT:-"ctrl-alt-n"}"
+  KEYS_TOGGLE_PLAYBACK="${KEYS_TOGGLE_PLAYBACK:-"ctrl-space"}"
+  KEYS_PLAY_NEXT="${KEYS_PLAY_NEXT:-"alt-n"}"
+  KEYS_PLAY_PREV="${KEYS_PLAY_PREV:-"alt-p"}"
+  KEYS_SEEK_FORWARD="${KEYS_SEEK_FORWARD:-"alt-N"}"
+  KEYS_SEEK_BACKWARD="${KEYS_SEEK_BACKWARD:-"alt-P"}"
+  KEYS_PLAYBACK="$KEYS_PLAY,$KEYS_QUEUE,$KEYS_QUEUE_NEXT,$KEYS_TOGGLE_PLAYBACK,$KEYS_PLAY_NEXT,$KEYS_PLAY_PREV,$KEYS_SEEK_FORWARD,$KEYS_SEEK_BACKWARD"
+  KEYS_N_PLAY="${KEYS_N_PLAY:-"."}"
+  KEYS_N_QUEUE="${KEYS_N_QUEUE:-";"}"
+  KEYS_N_QUEUE_NEXT="${KEYS_N_QUEUE_NEXT:-":"}"
+  KEYS_N_TOGGLE_PLAYBACK="${KEYS_N_TOGGLE_PLAYBACK:-"space"}"
+  KEYS_N_PLAY_NEXT="${KEYS_N_PLAY_NEXT:-"right,n"}"
+  KEYS_N_PLAY_PREV="${KEYS_N_PLAY_PREV:-"left,p"}"
+  KEYS_N_SEEK_FORWARD="${KEYS_N_SEEK_FORWARD:-"N,f"}"
+  KEYS_N_SEEK_BACKWARD="${KEYS_N_SEEK_BACKWARD:-"P,b"}"
+  KEYS_N_PLAYBACK="$KEYS_N_PLAY,$KEYS_N_QUEUE,$KEYS_N_QUEUE_NEXT,$KEYS_N_TOGGLE_PLAYBACK,$KEYS_N_PLAY_NEXT,$KEYS_N_PLAY_PREV,$KEYS_N_SEEK_FORWARD,$KEYS_N_SEEK_BACKWARD"
+  export KEYS_PLAY KEYS_QUEUE KEYS_QUEUE_NEXT KEYS_TOGGLE_PLAYBACK \
+    KEYS_PLAY_NEXT KEYS_PLAY_PREV KEYS_SEEK_FORWARD KEYS_SEEK_BACKWARD \
+    KEYS_PLAYBACK KEYS_N_PLAY KEYS_N_QUEUE KEYS_N_QUEUE_NEXT \
+    KEYS_N_TOGGLE_PLAYBACK KEYS_N_PLAY_NEXT KEYS_N_PLAY_PREV \
+    KEYS_N_SEEK_FORWARD KEYS_N_SEEK_BACKWARD KEYS_N_PLAYBACK
+
+  # Playlist (in the playlist, there is no `insert` mode):
+  KEYS_PLAYLIST_RELOAD="${KEYS_PLAYLIST_RELOAD:-"r,ctrl-r"}"
+  KEYS_PLAYLIST_REMOVE="${KEYS_PLAYLIST_REMOVE:-"x,delete"}"
+  KEYS_PLAYLIST_UP="${KEYS_PLAYLIST_UP:-"u"}"
+  KEYS_PLAYLIST_DOWN="${KEYS_PLAYLIST_DOWN:-"d"}"
+  KEYS_PLAYLIST_CLEAR="${KEYS_PLAYLIST_CLEAR:-"C"}"
+  KEYS_PLAYLIST_CLEAR_ABOVE="${KEYS_PLAYLIST_CLEAR_ABOVE:-"U"}"
+  KEYS_PLAYLIST_CLEAR_BELOW="${KEYS_PLAYLIST_CLEAR_BELOW:-"D"}"
+  KEYS_PLAYLIST_SHUFFLE="${KEYS_PLAYLIST_SHUFFLE:-"s"}"
+  KEYS_PLAYLIST_UNSHUFFLE="${KEYS_PLAYLIST_UNSHUFFLE:-"S"}"
+  KEYS_PLAYLIST_GOTO_RELEASE="${KEYS_PLAYLIST_GOTO_RELEASE:-"ctrl-g"}"
+  KEYS_PLAYLIST_STORE="${KEYS_PLAYLIST_STORE:-"ctrl-s"}"
+  KEYS_PLAYLIST_LOAD="${KEYS_PLAYLIST_LOAD:-"ctrl-o"}"
+  export KEYS_PLAYLIST_RELOAD KEYS_PLAYLIST_REMOVE KEYS_PLAYLIST_UP \
+    KEYS_PLAYLIST_DOWN KEYS_PLAYLIST_CLEAR KEYS_PLAYLIST_CLEAR_ABOVE \
+    KEYS_PLAYLIST_CLEAR_BELOW KEYS_PLAYLIST_SHUFFLE KEYS_PLAYLIST_UNSHUFFLE \
+    KEYS_PLAYLIST_GOTO_RELEASE KEYS_PLAYLIST_STORE KEYS_PLAYLIST_LOAD
+
+  export KEYS_LOADED=1
+fi
+
+# Local method to print keybindin groups
 #
+# @argument $1: Group name
+# @argument $2: Keys for first item
+# @argument $3: Description of first item
+# @argument $4: Keys for second item (optional)
+# @argument $5: Description of second item (optional)
+# @argument ...
+#
+# This is a helper method for printing key-binding groups.
+__keybindinggroup_from_args() {
+  printf "$KBF_GROUP\n" "$1"
+  shift
+  {
+    while [ "$*" ]; do
+      printf "$KBF_KEY:\t$KBF_DESC\n" "$1" "${2:-"no description"}"
+      shift
+      shift
+    done
+  } | column -t -s "$(printf '\t')"
+  #} | column -t -s "$(printf '\t')" -c "$FZF_PREVIEW_COLUMNS" -W 2
+  printf "\n\n"
+}
 
-# Mode selection:
-KEYS_I_NORMAL="${KEYS_I_NORMAL:-"esc"}"
-KEYS_N_INSERT="${KEYS_N_INSERT:-"a,i,/,?"}"
-export KEYS_I_NORMAL KEYS_N_INSERT
-
-# Vertical navigation:
-KEYS_DOWN="${KEYS_DOWN:-"ctrl-j,down"}"
-KEYS_UP="${KEYS_UP:-"ctrl-k,up"}"
-KEYS_HALFPAGE_DOWN="${KEYS_HALFPAGE_DOWN:-"ctrl-d"}"
-KEYS_HALFPAGE_UP="${KEYS_HALFPAGE_UP:-"ctrl-u"}"
-KEYS_N_DOWN="${KEYS_N_DOWN:-"j"}"
-KEYS_N_UP="${KEYS_N_UP:-"k"}"
-KEYS_N_BOT="${KEYS_N_BOT:-"G"}"
-KEYS_N_TOP="${KEYS_N_TOP:-"1"}"
-export KEYS_DOWN KEYS_UP KEYS_HALFPAGE_DOWN KEYS_HALFPAGE_UP KEYS_N_DOWN \
-  KEYS_N_UP KEYS_N_BOT KEYS_N_TOP
-
-# Horizontal navigation:
-KEYS_IN="${KEYS_IN:-"ctrl-l"}"
-KEYS_OUT="${KEYS_OUT:-"ctrl-h"}"
-KEYS_N_IN="${KEYS_N_IN:-"l"}"
-KEYS_N_OUT="${KEYS_N_OUT:-"h"}"
-KEYS_SELECT_ARTIST="${KEYS_SELECT_ARTIST:-"ctrl-a"}"
-KEYS_LIST_ARTISTS="${KEYS_LIST_ARTISTS:-"alt-a"}"
-KEYS_LIST_ALBUMS="${KEYS_LIST_ALBUMS:-"alt-s"}"
-KEYS_SEARCH_ARTIST="${KEYS_SEARCH_ARTIST:-"alt-z"}"
-KEYS_SEARCH_ALBUM="${KEYS_SEARCH_ALBUM:-"alt-x"}"
-KEYS_SWITCH_ARTIST_ALBUM="${KEYS_SWITCH_ARTIST_ALBUM:-"tab"}"
-KEYS_SWITCH_LOCAL_REMOTE="${KEYS_SWITCH_LOCAL_REMOTE:-"ctrl-/"}"
-export KEYS_IN KEYS_OUT KEYS_N_IN KEYS_N_OUT KEYS_SELECT_ARTIST \
-  KEYS_LIST_ARTISTS KEYS_SELECT_ARTIST KEYS_SEARCH_ALBUM \
-  KEYS_SWITCH_ARTIST_ALBUM KEYS_SWITCH_LOCAL_REMOTE
-
-# Filtering:
-KEYS_FILTER_LOCAL="${KEYS_FILTER_LOCAL:-"alt-l"}"
-KEYS_FILTER_1="${KEYS_FILTER_1:-"alt-1"}"
-KEYS_FILTER_2="${KEYS_FILTER_2:-"alt-2"}"
-KEYS_FILTER_3="${KEYS_FILTER_3:-"alt-3"}"
-KEYS_FILTER_4="${KEYS_FILTER_4:-"alt-4"}"
-KEYS_FILTER_5="${KEYS_FILTER_5:-"alt-5"}"
-KEYS_FILTER_6="${KEYS_FILTER_6:-"alt-6"}"
-KEYS_FILTER_7="${KEYS_FILTER_7:-"alt-7"}"
-KEYS_FILTER_8="${KEYS_FILTER_8:-"alt-8"}"
-KEYS_FILTER_9="${KEYS_FILTER_9:-"alt-9"}"
-KEYS_FILTER_0="${KEYS_FILTER_0:-"alt-0"}"
-KEYS_FILTER="$KEYS_FILTER_LOCAL,$KEYS_FILTER_1,$KEYS_FILTER_2,$KEYS_FILTER_3,$KEYS_FILTER_4,$KEYS_FILTER_5,$KEYS_FILTER_6,$KEYS_FILTER_7,$KEYS_FILTER_8,$KEYS_FILTER_9,$KEYS_FILTER_0"
-export KEYS_FILTER_LOCAL KEYS_FILTER_1 KEYS_FILTER_2 KEYS_FILTER_3 \
-  KEYS_FILTER_4 KEYS_FILTER_5 KEYS_FILTER_6 KEYS_FILTER_7 KEYS_FILTER_8 \
-  KEYS_FILTER_9 KEYS_FILTER_0 KEYS_FILTER
-
-# Specials:
-KEYS_BROWSE="${KEYS_BROWSE:-"alt-b"}"
-KEYS_OPEN="${KEYS_OPEN:-"alt-o"}"
-KEYS_SHOW_PLAYLIST="${KEYS_SHOW_PLAYLIST:-"ctrl-p"}"
-KEYS_QUIT="${KEYS_QUIT:-"ctrl-c"}"
-KEYS_N_QUIT="${KEYS_N_QUIT:-"q"}"
-export KEYS_BROWSE KEYS_OPEN KEYS_SHOW_PLAYLIST KEYS_QUIT KEYS_N_QUIT
-
-# Playback:
-KEYS_PLAY="${KEYS_PLAY:-"enter"}"
-KEYS_QUEUE="${KEYS_QUEUE:-"ctrl-alt-m"}" # That's actually alt-enter
-KEYS_QUEUE_NEXT="${KEYS_QUEUE_NEXT:-"ctrl-alt-n"}"
-KEYS_TOGGLE_PLAYBACK="${KEYS_TOGGLE_PLAYBACK:-"ctrl-space"}"
-KEYS_PLAY_NEXT="${KEYS_PLAY_NEXT:-"alt-n"}"
-KEYS_PLAY_PREV="${KEYS_PLAY_PREV:-"alt-p"}"
-KEYS_SEEK_FORWARD="${KEYS_SEEK_FORWARD:-"alt-N"}"
-KEYS_SEEK_BACKWARD="${KEYS_SEEK_BACKWARD:-"alt-P"}"
-KEYS_PLAYBACK="$KEYS_PLAY,$KEYS_QUEUE,$KEYS_QUEUE_NEXT,$KEYS_TOGGLE_PLAYBACK,$KEYS_PLAY_NEXT,$KEYS_PLAY_PREV,$KEYS_SEEK_FORWARD,$KEYS_SEEK_BACKWARD"
-KEYS_N_PLAY="${KEYS_N_PLAY:-"."}"
-KEYS_N_QUEUE="${KEYS_N_QUEUE:-";"}"
-KEYS_N_QUEUE_NEXT="${KEYS_N_QUEUE_NEXT:-":"}"
-KEYS_N_TOGGLE_PLAYBACK="${KEYS_N_TOGGLE_PLAYBACK:-"space"}"
-KEYS_N_PLAY_NEXT="${KEYS_N_PLAY_NEXT:-"right,n"}"
-KEYS_N_PLAY_PREV="${KEYS_N_PLAY_PREV:-"left,p"}"
-KEYS_N_SEEK_FORWARD="${KEYS_N_SEEK_FORWARD:-"N,f"}"
-KEYS_N_SEEK_BACKWARD="${KEYS_N_SEEK_BACKWARD:-"P,b"}"
-KEYS_N_PLAYBACK="$KEYS_N_PLAY,$KEYS_N_QUEUE,$KEYS_N_QUEUE_NEXT,$KEYS_N_TOGGLE_PLAYBACK,$KEYS_N_PLAY_NEXT,$KEYS_N_PLAY_PREV,$KEYS_N_SEEK_FORWARD,$KEYS_N_SEEK_BACKWARD"
-export KEYS_PLAY KEYS_QUEUE KEYS_QUEUE_NEXT KEYS_TOGGLE_PLAYBACK \
-  KEYS_PLAY_NEXT KEYS_PLAY_PREV KEYS_SEEK_FORWARD KEYS_SEEK_BACKWARD \
-  KEYS_PLAYBACK KEYS_N_PLAY KEYS_N_QUEUE KEYS_N_QUEUE_NEXT \
-  KEYS_N_TOGGLE_PLAYBACK KEYS_N_PLAY_NEXT KEYS_N_PLAY_PREV \
-  KEYS_N_SEEK_FORWARD KEYS_N_SEEK_BACKWARD KEYS_N_PLAYBACK
-
-# Playlist (in the playlist, there is no `insert` mode):
-KEYS_PLAYLIST_RELOAD="${KEYS_PLAYLIST_RELOAD:-"r,ctrl-r"}"
-KEYS_PLAYLIST_REMOVE="${KEYS_PLAYLIST_REMOVE:-"x,delete"}"
-KEYS_PLAYLIST_UP="${KEYS_PLAYLIST_UP:-"u"}"
-KEYS_PLAYLIST_DOWN="${KEYS_PLAYLIST_DOWN:-"d"}"
-KEYS_PLAYLIST_CLEAR="${KEYS_PLAYLIST_CLEAR:-"C"}"
-KEYS_PLAYLIST_CLEAR_ABOVE="${KEYS_PLAYLIST_CLEAR_ABOVE:-"U"}"
-KEYS_PLAYLIST_CLEAR_BELOW="${KEYS_PLAYLIST_CLEAR_BELOW:-"D"}"
-KEYS_PLAYLIST_GOTO_RELEASE="${KEYS_PLAYLIST_GOTO_RELEASE:-"ctrl-g"}"
-KEYS_PLAYLIST_STORE="${KEYS_PLAYLIST_STORE:-"ctrl-s"}"
-KEYS_PLAYLIST_LOAD="${KEYS_PLAYLIST_LOAD:-"ctrl-o"}"
-export KEYS_PLAYLIST_RELOAD KEYS_PLAYLIST_REMOVE KEYS_PLAYLIST_UP \
-  KEYS_PLAYLIST_DOWN KEYS_PLAYLIST_CLEAR KEYS_PLAYLIST_CLEAR_ABOVE \
-  KEYS_PLAYLIST_CLEAR_BELOW KEYS_PLAYLIST_GOTO_RELEASE KEYS_PLAYLIST_STORE \
-  KEYS_PLAYLIST_LOAD
+# Print view-dependent keybindings
+#
+# @argument $1: view
+#
+# This method pretty-prints the keybindings active at the given view.
+print_keybindings() {
+  view=$1
+  case "$view" in
+  "$VIEW_SELECT_ARTIST")
+    __keybindinggroup_from_args "Previews" \
+      "$KEYS_SCROLL_PREVIEW_DOWN" "Scroll preview down" \
+      "$KEYS_SCROLL_PREVIEW_UP" "Scroll preview up" \
+      "$KEYS_KEYBINDINGS" "Show these keybindings" \
+      "$KEYS_PREVIEW_OPEN" "Open preview window" \
+      "$KEYS_PREVIEW_CLOSE" "Close preview window"
+    __keybindinggroup_from_args "Navigation" \
+      "$KEYS_DOWN" "Down" \
+      "$KEYS_UP" "Up" \
+      "$KEYS_HALFPAGE_DOWN" "Down half a page" \
+      "$KEYS_HALFPAGE_UP" "Up half a page" \
+      "enter,$KEYS_IN" "Go to selected artist" \
+      "$KEYS_OUT,$KEYS_QUIT" "Return to previews view"
+    __keybindinggroup_from_args "Views" \
+      "$KEYS_LIST_ARTISTS" "Display artists in local database" \
+      "$KEYS_LIST_ALBUMS" "Display albums in local database" \
+      "$KEYS_SEARCH_ARTIST" "Show artist on MusicBrainz" \
+      "$KEYS_SEARCH_ALBUM" "Show album on MusicBrainz"
+    __keybindinggroup_from_args "Special operations" \
+      "$KEYS_SHOW_PLAYLIST" "Show playlist" \
+      "$KEYS_BROWSE" "Open artist in browser"
+    __keybindinggroup_from_args "Filtering" \
+      "$KEYS_FILTER_LOCAL" "Show only entries in local database"
+    ;;
+  "$VIEW_PLAYLIST")
+    __keybindinggroup_from_args "Previews" \
+      "$KEYS_SCROLL_PREVIEW_DOWN" "Scroll preview down" \
+      "$KEYS_SCROLL_PREVIEW_UP" "Scroll preview up" \
+      "$KEYS_KEYBINDINGS" "Show these keybindings" \
+      "$KEYS_PREVIEW_CLOSE" "Close preview window"
+    __keybindinggroup_from_args "Navigation" \
+      "$KEYS_DOWN,$KEYS_N_DOWN" "Down" \
+      "$KEYS_UP,$KEYS_N_UP" "Up" \
+      "$KEYS_HALFPAGE_DOWN" "Down half a page" \
+      "$KEYS_HALFPAGE_UP" "Up half a page" \
+      "$KEYS_N_TOP" "Go to first entry" \
+      "$KEYS_N_BOT" "Go to last entry" \
+      "$KEYS_OUT,$KEYS_N_OUT,$KEYS_QUIT,$KEYS_N_QUIT" "Leave playlist view" \
+      "$KEYS_SELECT_ARTIST" "Go to artist of selected item"
+    __keybindinggroup_from_args "Views" \
+      "$KEYS_LIST_ARTISTS" "Display artists in local database" \
+      "$KEYS_LIST_ALBUMS" "Display albums in local database" \
+      "$KEYS_SEARCH_ARTIST" "Show artist on MusicBrainz" \
+      "$KEYS_SEARCH_ALBUM" "Show album on MusicBrainz"
+    __keybindinggroup_from_args "Playlist" \
+      "$KEYS_PLAYLIST_RELOAD" "Reload playlist" \
+      "$KEYS_PLAYLIST_REMOVE" "Remove selected track" \
+      "$KEYS_PLAYLIST_UP" "Move track up" \
+      "$KEYS_PLAYLIST_DOWN" "Move track down" \
+      "$KEYS_PLAYLIST_CLEAR" "Clear playlist" \
+      "$KEYS_PLAYLIST_CLEAR_ABOVE" "Remove all tracks above" \
+      "$KEYS_PLAYLIST_CLEAR_BELOW" "Remove all tracks below" \
+      "$KEYS_PLAYLIST_SHUFFLE" "Shuffle" \
+      "$KEYS_PLAYLIST_UNSHUFFLE" "Undo shuffle" \
+      "$KEYS_PLAYLIST_GOTO_RELEASE" "Show release of selected track"
+    __keybindinggroup_from_args "Playback" \
+      "$KEYS_PLAY,$KEYS_N_PLAY" "Play selected item" \
+      "$KEYS_QUEUE,$KEYS_N_QUEUE" "Queue selected item" \
+      "$KEYS_QUEUE_NEXT,$KEYS_N_QUEUE_NEXT" "Play selected item next" \
+      "$KEYS_TOGGLE_PLAYBACK,$KEYS_N_TOGGLE_PLAYBACK" "Toggle playback" \
+      "$KEYS_PLAY_NEXT,$KEYS_N_PLAY_NEXT" "Play next track" \
+      "$KEYS_PLAY_PREV,$KEYS_N_PLAY_PREV" "Play previous track" \
+      "$KEYS_SEEK_FORWARD,$KEYS_N_SEEK_FORWARD" "Seek forward" \
+      "$KEYS_SEEK_BACKWARD,$KEYS_N_SEEK_BACKWARD" "Seek backward"
+    __keybindinggroup_from_args "Special operations" \
+      "$KEYS_BROWSE" "Open selected item in browser" \
+      "$KEYS_OPEN" "Open selected item in file manager" \
+      "$KEYS_N_YANK" "Copy MusicBrainz track ID" \
+      "$KEYS_YANK_CURRENT" "Copy MusicBrainz release ID"
+    ;;
+  *)
+    __keybindinggroup_from_args "Switch between modes" \
+      "$KEYS_I_NORMAL" "Swtich to normal mode (insert)" \
+      "$KEYS_N_INSERT" "Swtich to insert mode (normal)"
+    __keybindinggroup_from_args "Previews" \
+      "$KEYS_SCROLL_PREVIEW_DOWN" "Scroll preview down" \
+      "$KEYS_SCROLL_PREVIEW_UP" "Scroll preview up" \
+      "$KEYS_KEYBINDINGS" "Show these keybindings" \
+      "$KEYS_PREVIEW_OPEN" "Open preview window" \
+      "$KEYS_PREVIEW_CLOSE" "Close preview window"
+    __keybindinggroup_from_args "Navigation" \
+      "$KEYS_DOWN" "Down" \
+      "$KEYS_UP" "Up" \
+      "$KEYS_N_DOWN" "Down (normal)" \
+      "$KEYS_N_UP" "Up (normal)" \
+      "$KEYS_HALFPAGE_DOWN" "Down half a page" \
+      "$KEYS_HALFPAGE_UP" "Up half a page" \
+      "$KEYS_N_TOP" "Go to first entry (normal)" \
+      "$KEYS_N_BOT" "Go to last entry (normal)" \
+      "$KEYS_IN" "Open selected item" \
+      "$KEYS_N_IN" "Open selected item (normal)" \
+      "$KEYS_OUT" "Leave current item" \
+      "$KEYS_N_OUT" "Leave current item (normal)" \
+      "$KEYS_SELECT_ARTIST" "Go to artist of selected item"
+    __keybindinggroup_from_args "Views" \
+      "$KEYS_LIST_ARTISTS" "Display artists in local database" \
+      "$KEYS_LIST_ALBUMS" "Display albums in local database" \
+      "$KEYS_SEARCH_ARTIST" "Show artist on MusicBrainz" \
+      "$KEYS_SEARCH_ALBUM" "Show album on MusicBrainz" \
+      "$KEYS_SWITCH_ARTIST_ALBUM" "Swtich artist / album" \
+      "$KEYS_SWITCH_LOCAL_REMOTE" "Swtich local database / MusicBrainz"
+    __keybindinggroup_from_args "Filtering" \
+      "$KEYS_FILTER_LOCAL" "Show only entries in local database" \
+      "$KEYS_FILTER_0" "Clear filter" \
+      "$KEYS_FILTER_1" "Reset filter to default for current view" \
+      "$KEYS_FILTER_2" "Custom filter" \
+      "$KEYS_FILTER_3" "Custom filter" \
+      "$KEYS_FILTER_4" "Custom filter" \
+      "$KEYS_FILTER_5" "Custom filter" \
+      "$KEYS_FILTER_6" "Custom filter" \
+      "$KEYS_FILTER_7" "Custom filter" \
+      "$KEYS_FILTER_8" "Custom filter" \
+      "$KEYS_FILTER_9" "Custom filter"
+    __keybindinggroup_from_args "Playback" \
+      "$KEYS_PLAY" "Play selected item" \
+      "$KEYS_QUEUE" "Queue selected item" \
+      "$KEYS_QUEUE_NEXT" "Play selected item next" \
+      "$KEYS_TOGGLE_PLAYBACK" "Toggle playback" \
+      "$KEYS_PLAY_NEXT" "Play next track" \
+      "$KEYS_PLAY_PREV" "Play previous track" \
+      "$KEYS_SEEK_FORWARD" "Seek forward" \
+      "$KEYS_SEEK_BACKWARD" "Seek backward"
+    __keybindinggroup_from_args "Playback (normal)" \
+      "$KEYS_N_PLAY" "Play selected item" \
+      "$KEYS_N_QUEUE" "Queue selected item" \
+      "$KEYS_N_QUEUE_NEXT" "Play selected item next" \
+      "$KEYS_N_TOGGLE_PLAYBACK" "Toggle playback" \
+      "$KEYS_N_PLAY_NEXT" "Play next track" \
+      "$KEYS_N_PLAY_PREV" "Play previous track" \
+      "$KEYS_N_SEEK_FORWARD" "Seek forward" \
+      "$KEYS_N_SEEK_BACKWARD" "Seek backward"
+    __keybindinggroup_from_args "Special operations" \
+      "$KEYS_SHOW_PLAYLIST" "Show playlist" \
+      "$KEYS_BROWSE" "Open selected item in browser" \
+      "$KEYS_OPEN" "Open selected item in file manager" \
+      "$KEYS_N_YANK" "Copy selected MusicBrainz ID (normal)" \
+      "$KEYS_YANK_CURRENT" "Copy current MusicBrainz ID" \
+      "$KEYS_REFRESH" "Refresh current entry" \
+      "$KEYS_QUIT" "Quit applicaion" \
+      "$KEYS_N_QUIT" "First view or quit (normal)"
+    ;;
+  esac
+}

src/sh/lists.sh

@@ -1,5 +1,8 @@
+# These methods generate lists that are used as input to FZF.
+
 # List release groups of given artist
-# argument $1: MB artist id
+#
+# argument $1: MusicBrainz artist ID
 list_releasegroups() {
   name=$(mb_artist "$1" | $JQ '.name')
   mb_artist_releasegroups "$1" |
@@ -47,7 +50,8 @@ list_releasegroups() {
 }
 
 # List releases in given relese group
-# argument $1: MB release-group id
+#
+# argument $1: MusicBrainz release-group ID
 list_releases() {
   title="$(mb_releasegroup "$1" |
     $JQ '.title')"
@@ -76,10 +80,10 @@ list_releases() {
       -v release_withdrawn="$FORMAT_STATUS_WITHDRAWN" \
       -v release_expunged="$FORMAT_STATUS_EXPUNGED" \
       -v release_cancelled="$FORMAT_STATUS_CANCELLED" \
-      -v release_format="$RV_FORMAT" \
-      -v release_format_title_artist="$RV_TITLE_ARTIST" \
-      -v release_format_title="$RV_TITLE" \
-      -v release_format_artist="$RV_ARTIST" \
+      -v format_release="$RV_FORMAT" \
+      -v format_release_title_artist="$RV_TITLE_ARTIST" \
+      -v format_release_title="$RV_TITLE" \
+      -v format_release_artist="$RV_ARTIST" \
       -v rg_artist="$artist" \
       -v rg_title="$title" \
       -v rgid="$1" \
@@ -92,7 +96,8 @@ list_releases() {
 }
 
 # List recordings of given release
-# argument $1: MB release id
+#
+# argument $1: MusicBrainz release ID
 list_recordings() {
   deco="$(grep "$1" "$LOCALDATA_RELEASES" | cut -d "$(printf '\t')" -f 2)"
   if [ "$deco" ]; then
@@ -131,22 +136,19 @@ list_recordings() {
   fi
 }
 
-# List artists (local)
+# List artists available locally
 list_local_artists() {
   cat "$LOCALDATA_ARTISTS_VIEW" 2>/dev/null
 }
 
-# List release groups (local)
+# List release groups vailable locally
 list_local_releasegroups() {
   cat "$LOCALDATA_RELEASEGROUPS_VIEW" 2>/dev/null
 }
 
-# List releases (local)
-list_local_releases() {
-  cat "$LOCALDATA_RELEASES_VIEW" 2>/dev/null
-}
-
-# Generate artist list from JSON
+# List artist from input json data
+#
+# The input is read from stdin
 list_artists_from_json() {
   cat |
     $JQ 'map([.artist.id, .artist.type, .name] | join("\t")) | join("\n")' |
@@ -158,11 +160,10 @@ list_artists_from_json() {
       -v format_disambiguation="$AV_DISAMBIGUATION" \
       -v format_local="$FORMAT_LOCAL" \
       "$AWK_ARTISTS" |
-    column -t -s "$(printf '\t')" |
-    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|'
+    column -t -s "$(printf '\t')" -l 2
 }
 
-# Generate playlist view
+# Print playlist currently loaded
 list_playlist() {
   count=$(mpv_playlist_count)
   [ "$count" -eq 0 ] && return 0

src/sh/local.sh

@@ -1,4 +1,36 @@
-gettags() {
+# Database functionality to support local music.
+#
+# All local data is stored in the directory `LOCALDATADIR`. In the future, we
+# will also use the methods here, and modifications thereof, to support
+# MusicBainz collections.
+if [ ! "${LOCAL_LOADED:-}" ]; then
+  LOCALDATADIR="$HOME/.cache/$APP_NAME/local"
+  LOCALDATA_ARTISTS="$LOCALDATADIR/artists"
+  LOCALDATA_RELEASEGROUPS="$LOCALDATADIR/releasegroups"
+  LOCALDATA_RELEASES="$LOCALDATADIR/releases"
+  LOCALDATA_ARTISTS_VIEW="$LOCALDATADIR/artists_view"
+  LOCALDATA_RELEASEGROUPS_VIEW="$LOCALDATADIR/releasegroups_view"
+  LOCALDATA_RELEASES_VIEW="$LOCALDATADIR/releases_view"
+  LOCALDATA_ARTISTS_LIST="$LOCALDATADIR/artists_list"
+  LOCALDATA_RELEASEGROUPS_LIST="$LOCALDATADIR/releasegroups_list"
+  LOCALDATA_RELEASES_LIST="$LOCALDATADIR/releases_list"
+  DECORATION_FILENAME=${DECORATION_FILENAME:-"mbid.json"}
+
+  export LOCALDATADIR LOCALDATA_ARTISTS LOCALDATA_RELEASEGROUPS \
+    LOCALDATA_RELEASES LOCALDATA_ARTISTS_VIEW LOCALDATA_RELEASEGROUPS_VIEW \
+    LOCALDATA_RELEASES_VIEW LOCALDATA_ARTISTS_LIST LOCALDATA_RELEASEGROUPS_LIST \
+    LOCALDATA_RELEASES_LIST DECORATION_FILENAME
+
+  export LOCAL_LOADED=1
+fi
+
+# Retrieve tags as json object from music file
+#
+# @argument $1: path to music file
+#
+# The tags retrieved are the MusicBrainz release ID and the MusicBrainz track
+# ID
+__gettags() {
   ffprobe -v error -show_entries format_tags -print_format json "$1" |
     $JQ '.format.tags | {
       trackid: (."MusicBrainz Release Track Id" // ."MUSICBRAINZ_RELEASETRACKID" // ."MusicBrainz/Release Track Id" // ""),
@@ -6,9 +38,14 @@ gettags() {
     }'
 }
 
-# Read music files in specified directory and create json file that points to
-# all relevant MusicBrainz IDs.
+# Decorate locally available music
+#
 # @input $1: Path to directory with album
+#
+# This methods reads the music files in the specified directory and writes a
+# json file that points to all relevant MusicBrainz IDs. If the directory
+# contains untagged files, or files of different releases, then the decoration
+# process will fail, and an error is printed.
 decorate() {
   if [ -f "$1/$DECORATION_FILENAME" ]; then
     info "Directory $1 has already been decorated (skipping)"
@@ -16,9 +53,9 @@ decorate() {
   fi
   decoration=$($JQ -n '.tracks = {}')
   tmpf=$(mktemp)
-  (cd "$1" && find . -type f -iname '*.mp3' -o -iname '*.mp4' -o -iname '*.flac' -o -iname '*.m4a') >"$tmpf"
+  (cd "$1" && find . -type f -iname '*.mp3' -o -iname '*.mp4' -o -iname '*.flac' -o -iname '*.m4a' -o -iname '*.ogg') >"$tmpf"
   while IFS= read -r f; do
-    mbid=$(gettags "$1/$f")
+    mbid=$(__gettags "$1/$f")
     rid=$(echo "$mbid" | $JQ '.releaseid')
     tid=$(echo "$mbid" | $JQ '.trackid')
     if [ ! "$rid" ] || [ ! "$tid" ]; then
@@ -46,193 +83,271 @@ decorate() {
   fi
 }
 
+# Decorate locally available music with specified MusicBrainz release
+#
+# @input $1: Path to directory with album
+# @input $2: MusicBrainz release ID
+#
+# Similar as `decorate`, but the MusicBrainz IDs are not inferred from the
+# tags, but passed as argument.
+decorate_as() {
+  if [ -f "$1/$DECORATION_FILENAME" ]; then
+    rid="$($JQ '.releaseid' "$1/$DECORATION_FILENAME")"
+    title="$(mb_release "$rid" | $JQ '.title // ""')"
+    artist="$(mb_release "$rid" | $JQ '."artist-credit" | map([.name, .joinphrase] | join("")) | join("")')"
+    [ "$rid" = "$2" ] &&
+      info "Directory $1 has already been decorated as the release '$title' - '$artist' with the identical MusicBrainz release ID." ||
+      info "Directory $1 has already been decorated as the release '$title' - '$artist' with the MusicBrainz release ID $rid."
+    while true; do
+      infonn "Do you want to redecorate $1? (yes/no)"
+      read -r yn
+      case $yn in
+      "yes") break ;;
+      "no") return 0 ;;
+      *) info "Please answer \"yes\" or \"no\"." ;;
+      esac
+    done
+  fi
+  # Print info
+  title="$(mb_release "$2" | $JQ '.title // ""')"
+  artist="$(mb_release "$2" | $JQ '."artist-credit" | map([.name, .joinphrase] | join("")) | join("")')"
+  info "Decorating $1 as the release $title by $artist"
+  # Start decoration
+  decoration=$($JQ -n '.tracks = {}')
+  tmpf=$(mktemp)
+  (cd "$1" && find . -type f -iname '*.mp3' -o -iname '*.mp4' -o -iname '*.flac' -o -iname '*.m4a' -o -iname '*.ogg' | sort) >"$tmpf"
+  # Compare number of tracks with release
+  rcnt="$(mb_release "$2" | $JQ '.media | map(."track-count") | add')"
+  dcnt="$(wc -l "$tmpf" | cut -d ' ' -f 1)"
+  if [ ! "$rcnt" -eq "$dcnt" ]; then
+    err "Number of tracks in directory ($dcnt) does not match number of tracks in release ($rcnt)."
+    return 1
+  fi
+  #
+  tmpj=$(mktemp)
+  mb_release "$2" |
+    $JQ '.media[] |
+    .position as $pos |
+    .tracks |
+    map({
+      $pos,
+      "id": .id,
+      "n": .number,
+      "t": .title
+    }) |
+    map(if(.n | type == "string" and test("^[0-9]+$")) then .n |= tonumber else . end) |
+    sort_by([.pos, .n])[] |
+    [.t, .id] |
+    join("\t")' >"$tmpj"
+  assocfile=$(mktemp)
+  awk -F '\t' '
+BEGIN { OFS = "\t" }
+FNR == NR { title[FNR] = $1; id[FNR] = $2 }
+FNR != NR { fname[FNR] = $1 }
+END { for (i in id) print title[i], id[i], fname[i] }
+' "$tmpj" "$tmpf" >"$assocfile"
+  rm -f "$tmpj" "$tmpf"
+  # Ask user if this is ok
+  info "We discovered the following associatoin:"
+  while IFS= read -r line; do
+    t="$(echo "$line" | cut -d "$(printf '\t')" -f 1)"
+    f="$(echo "$line" | cut -d "$(printf '\t')" -f 3)"
+    printf "Track '%s'\tFile '%s'\n" "$t" "$f"
+  done <"$assocfile" | column -t -s "$(printf '\t')"
+  while true; do
+    infonn "Are the track correctly associated to the audio files? (yes/no)"
+    read -r yn
+    case $yn in
+    "yes") break ;;
+    "no") return 0 ;;
+    *) info "Please answer \"yes\" or \"no\"." ;;
+    esac
+  done
+  # Construct decoration
+  decoration=$($JQ -n '.tracks = {}')
+  while IFS= read -r line; do
+    i="$(echo "$line" | cut -d "$(printf '\t')" -f 2)"
+    f="$(echo "$line" | cut -d "$(printf '\t')" -f 3)"
+    decoration=$(echo "$decoration" | $JQ ".tracks += {\"$i\": \"$f\"}")
+  done <"$assocfile"
+  echo "$decoration" | $JQ ".releaseid = \"$2\"" >"$1/$DECORATION_FILENAME"
+  return 0
+}
+
 # Load missing cache entries (batch mode)
+#
 # argument $1: type
-# argument $2: File with one ID per line
+#
+# This method reads one MusicBrainz IDs of the specified type from stdin (one
+# per line), and fetches the missing items.
 __batch_load_missing() {
   tmpf=$(mktemp)
-  while IFS= read -r mbid; do
-    if ! in_cache "$1" "$mbid"; then
-      echo "$mbid" >>"$tmpf"
-    fi
-  done <"$2"
-  if [ -s "$tmpf" ]; then
-    lines=$(wc -l "$tmpf" | cut -d ' ' -f 1)
-    if [ "$lines" -gt 0 ]; then
+  cat |
+    cache_get_file_batch "$1" |
+    xargs \
+      sh -c 'for f; do [ -e "$f" ] || echo "$f"; done' _ |
+    cache_mbid_from_path_batch >"$tmpf"
+  lines=$(wc -l "$tmpf" | cut -d ' ' -f 1)
+  if [ "$lines" -gt 0 ]; then
+    case "$1" in
+    "$TYPE_ARTIST") tt="artists" ;;
+    "$TYPE_RELEASEGROUP") tt="release groups" ;;
+    "$TYPE_RELEASE") tt="releases" ;;
+    esac
+    info "Fetching missing $tt"
+    cnt=0
+    while IFS= read -r mbid; do
       case "$1" in
       "$TYPE_ARTIST")
-        tt="artists"
-        ;;
-      "$TYPE_RELEASEGROUP")
-        tt="release groups"
-        ;;
-      "$TYPE_RELEASE")
-        tt="releases"
+        name=$(mb_artist "$mbid" | $JQ '.name')
         ;;
+      "$TYPE_RELEASEGROUP") name=$(mb_releasegroup "$mbid" | $JQ '.title') ;;
+      "$TYPE_RELEASE") name=$(mb_release "$mbid" | $JQ '.title') ;;
       esac
-      info "Fetching $lines missing $tt"
-      cnt=0
-      while IFS= read -r mbid; do
-        case "$1" in
-        "$TYPE_ARTIST")
-          name=$(mb_artist "$mbid" | $JQ ".name")
-          ;;
-        "$TYPE_RELEASEGROUP")
-          name=$(mb_releasegroup "$mbid" | $JQ ".title")
-          ;;
-        "$TYPE_RELEASE")
-          name=$(mb_release "$mbid" | $JQ ".title")
-          ;;
-        esac
-        cnt=$((cnt + 1))
-        printf "\033[2K\r%d/%d (%s: %s)" "$cnt" "$lines" "$mbid" "$name"
-        sleep 1
-      done <"$tmpf"
-      printf "\n"
-    fi
+      cnt=$((cnt + 1))
+      info "$(printf "%d/%d (%s: %s)" "$cnt" "$lines" "$mbid" "$name")"
+      sleep 1
+    done <"$tmpf"
   fi
   rm -f "$tmpf"
 }
 
-LOCALDATADIR="$HOME/.cache/$APP_NAME/local"
-LOCALDATA_ARTISTS="$LOCALDATADIR/artists"
-LOCALDATA_RELEASEGROUPS="$LOCALDATADIR/releasegroups"
-LOCALDATA_RELEASES="$LOCALDATADIR/releases"
-LOCALDATA_ARTISTS_VIEW="$LOCALDATADIR/artists_view"
-LOCALDATA_RELEASEGROUPS_VIEW="$LOCALDATADIR/releasegroups_view"
-LOCALDATA_RELEASES_VIEW="$LOCALDATADIR/releases_view"
-DECORATION_FILENAME=${DECORATION_FILENAME:-"mbid.json"}
-
-# Precompute views
-precompute_view() {
-  info "Precomputing artist view"
-  while IFS= read -r aid; do
-    mb_artist "$aid" | $JQ '[
-    .id,
-    .type,
-    .name,
-    .disambiguation,
-    .["life-span"].begin,
-    .["life-span"].end
-    ] | join("\t")'
-  done <"$LOCALDATA_ARTISTS" |
-    awk \
-      -F "\t" \
-      -v file_local_artists="${LOCALDATA_ARTISTS:-}" \
-      -v format_person="$AV_PERSON" \
-      -v format_group="$AV_GROUP" \
-      -v format_disambiguation="$AV_DISAMBIGUATION" \
-      -v format_local="$FORMAT_LOCAL" \
-      "$AWK_ARTISTS" |
-    sort |
-    column -t -s "$(printf '\t')" -E 0 |
-    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|' >"$LOCALDATA_ARTISTS_VIEW"
-  info "Precomputing releasegroup view"
-  while IFS= read -r rgid; do
-    mb_releasegroup "$rgid" | $JQ '[
-    .id,
-    ."primary-type",
-    (."secondary-types" // []|join(";")),
-    ."first-release-date",
-    .title,
-    (."artist-credit" | map(([.name, .joinphrase]|join(""))) | join(""))
-    ] | join("\t")'
-  done <"$LOCALDATA_RELEASEGROUPS" |
-    awk \
-      -F "\t" \
-      -v file_local_releasegroups="${LOCALDATA_RELEASEGROUPS:-}" \
-      -v format_release="$RGV_RELEASE" \
-      -v format_release_w_artist="$RGV_RELEASE_W_ARTIST" \
-      -v format_year="$RGV_YEAR" \
-      -v format_album="$FORMAT_TYPE_ALBUM" \
-      -v format_single="$FORMAT_TYPE_SINGLE" \
-      -v format_ep="$FORMAT_TYPE_EP" \
-      -v format_broadcast="$FORMAT_TYPE_BROADCAST" \
-      -v format_other="$FORMAT_TYPE_OTHER" \
-      -v format_has_secondary="$FORMAT_TYPE_HAS_SECONDARY" \
-      -v format_secondary="$FORMAT_TYPE_SECONDARY" \
-      -v format_compilation="$FORMAT_TYPE_SECONDARY_COMPILATION" \
-      -v format_soundtrack="$FORMAT_TYPE_SECONDARY_SOUNDTRACK" \
-      -v format_spokenword="$FORMAT_TYPE_SECONDARY_SPOKENWORD" \
-      -v format_interview="$FORMAT_TYPE_SECONDARY_INTERVIEW" \
-      -v format_audiobook="$FORMAT_TYPE_SECONDARY_AUDIOBOOK" \
-      -v format_audiodrama="$FORMAT_TYPE_SECONDARY_AUDIODRAMA" \
-      -v format_live="$FORMAT_TYPE_SECONDARY_LIVE" \
-      -v format_remix="$FORMAT_TYPE_SECONDARY_REMIX" \
-      -v format_djmix="$FORMAT_TYPE_SECONDARY_DJMIX" \
-      -v format_mixtape="$FORMAT_TYPE_SECONDARY_MIXTAPE" \
-      -v format_demo="$FORMAT_TYPE_SECONDARY_DEMO" \
-      -v format_fieldrec="$FORMAT_TYPE_SECONDARY_FIELDREC" \
-      -v format_local="$FORMAT_LOCAL" \
-      "$AWK_RELEASEGROUPS" |
-    sort -n -r |
-    cut -d "$(printf '\t')" -f 2- |
-    column -t -s "$(printf '\t')" -E 0 |
-    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|' >"$LOCALDATA_RELEASEGROUPS_VIEW"
-  info "Precomputing release view"
-  cut -d "$(printf '\t')" -f 1 "$LOCALDATA_RELEASES" |
-    while IFS= read -r rid; do
-      mb_release "$rid" | $JQ '[
+# Precompute lists
+#
+# The main views (VIEW_ARTIST and TYPE_RELEASEGROUP) for locally available
+# music are theme dependent. These views are generated from the lists that are
+# produced with the present method. It contains all essential data, but in a
+# theme-independent fashion. The lists are stored in the files
+# `LOCALDATA_ARTISTS_LIST` and `LOCALDATA_RELEASEGROUPS_LIST`.
+__precompute_lists() {
+  cache_get_file_batch "$TYPE_ARTIST" <"$LOCALDATA_ARTISTS" | xargs \
+    $JQ '[
       .id,
-      .status,
-      .date,
-      ."cover-art-archive".count,
-      (."label-info" | map(.label.name) | unique | join(", ")),
-      (.media | map(."track-count") | add),
-      (.media | map(.format) | unique | join(", ")),
-      .country,
+      .type,
+      .name,
+      .disambiguation,
+      .["life-span"].begin,
+      .["life-span"].end
+      ] | join("\t")' >"$LOCALDATA_ARTISTS_LIST"
+  cache_get_file_batch "$TYPE_RELEASEGROUP" <"$LOCALDATA_RELEASEGROUPS" | xargs \
+    $JQ '[
+      .id,
+      ."primary-type",
+      (."secondary-types" // []|join(";")),
+      ."first-release-date",
       .title,
       (."artist-credit" | map(([.name, .joinphrase]|join(""))) | join(""))
-      ] | join("\t")'
-    done |
-    awk \
-      -F "\t" \
-      -v file_local_releases="${LOCALDATA_RELEASES:-}" \
-      -v release_official="$FORMAT_STATUS_OFFICIAL" \
-      -v release_promotion="$FORMAT_STATUS_PROMO" \
-      -v release_bootleg="$FORMAT_STATUS_BOOTLEG" \
-      -v release_pseudo="$FORMAT_STATUS_PSEUDO" \
-      -v release_withdrawn="$FORMAT_STATUS_WITHDRAWN" \
-      -v release_expunged="$FORMAT_STATUS_EXPUNGED" \
-      -v release_cancelled="$FORMAT_STATUS_CANCELLED" \
-      -v release_format="$RV_FORMAT" \
-      -v release_format_title_artist="$RV_TITLE_ARTIST" \
-      -v release_format_title="$RV_TITLE" \
-      -v release_format_artist="$RV_ARTIST" \
-      -v format_local="$FORMAT_LOCAL" \
-      "$AWK_RELEASES" |
-    sort -n -r |
+      ] | join("\t")' >"$LOCALDATA_RELEASEGROUPS_LIST"
+}
+
+# Precompute views
+#
+# This method injects the theme elements to the lists from `precompute_lists`.
+# The resulting views are stored in the files `LOCALDATA_ARTISTS_VIEW` and
+# `LOCALDATA_RELEASEGROUPS_VIEW`.
+precompute_views() {
+  awk \
+    -F "\t" \
+    -v file_local_artists="${LOCALDATA_ARTISTS:-}" \
+    -v format_person="$AV_PERSON" \
+    -v format_group="$AV_GROUP" \
+    -v format_disambiguation="$AV_DISAMBIGUATION" \
+    -v format_local="$FORMAT_LOCAL" \
+    "$AWK_ARTISTS" "$LOCALDATA_ARTISTS_LIST" |
+    sort |
+    column -t -s "$(printf '\t')" -l 2 >"$LOCALDATA_ARTISTS_VIEW"
+  #column -t -s "$(printf '\t')" |
+  #sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|' >"$LOCALDATA_ARTISTS_VIEW"
+  awk \
+    -F "\t" \
+    -v file_local_releasegroups="${LOCALDATA_RELEASEGROUPS:-}" \
+    -v format_release="$RGV_RELEASE" \
+    -v format_release_w_artist="$RGV_RELEASE_W_ARTIST" \
+    -v format_year="$RGV_YEAR" \
+    -v format_album="$FORMAT_TYPE_ALBUM" \
+    -v format_single="$FORMAT_TYPE_SINGLE" \
+    -v format_ep="$FORMAT_TYPE_EP" \
+    -v format_broadcast="$FORMAT_TYPE_BROADCAST" \
+    -v format_other="$FORMAT_TYPE_OTHER" \
+    -v format_has_secondary="$FORMAT_TYPE_HAS_SECONDARY" \
+    -v format_secondary="$FORMAT_TYPE_SECONDARY" \
+    -v format_compilation="$FORMAT_TYPE_SECONDARY_COMPILATION" \
+    -v format_soundtrack="$FORMAT_TYPE_SECONDARY_SOUNDTRACK" \
+    -v format_spokenword="$FORMAT_TYPE_SECONDARY_SPOKENWORD" \
+    -v format_interview="$FORMAT_TYPE_SECONDARY_INTERVIEW" \
+    -v format_audiobook="$FORMAT_TYPE_SECONDARY_AUDIOBOOK" \
+    -v format_audiodrama="$FORMAT_TYPE_SECONDARY_AUDIODRAMA" \
+    -v format_live="$FORMAT_TYPE_SECONDARY_LIVE" \
+    -v format_remix="$FORMAT_TYPE_SECONDARY_REMIX" \
+    -v format_djmix="$FORMAT_TYPE_SECONDARY_DJMIX" \
+    -v format_mixtape="$FORMAT_TYPE_SECONDARY_MIXTAPE" \
+    -v format_demo="$FORMAT_TYPE_SECONDARY_DEMO" \
+    -v format_fieldrec="$FORMAT_TYPE_SECONDARY_FIELDREC" \
+    -v format_local="$FORMAT_LOCAL" \
+    "$AWK_RELEASEGROUPS" "$LOCALDATA_RELEASEGROUPS_LIST" | sort -n -r |
     cut -d "$(printf '\t')" -f 2- |
-    column -t -s "$(printf '\t')" -E 0 |
-    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\):\(.*$\)$|\t\1\t\2\t\3|' >"$LOCALDATA_RELEASES_VIEW"
+    column -t -s "$(printf '\t')" -l 5 >"$LOCALDATA_RELEASEGROUPS_VIEW"
+  #column -t -s "$(printf '\t')" |
+  #sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|' >"$LOCALDATA_RELEASEGROUPS_VIEW"
 }
 
 # Load local music
+#
 # argument $1: path to decorated music files
-load_local() {
-  [ -d "$LOCALDATADIR" ] || mkdir -p "$LOCALDATADIR"
-  tmpreleases=$(mktemp)
-  [ -f "$tmpreleases" ] || exit 1
-  info "Locating and parsing decoration files ($DECORATION_FILENAME)"
+#
+# This method parses all decorations and generates a line-by-line database of
+# locally available artists, releases, and release groups. This data is stored
+# in the files `LOCALDATA_ARTISTS`, `LOCALDATA_RELEASES`, and
+# `LOCALDATA_RELEASEGROUPS`.
+reloaddb() {
+  rm -rf "$LOCALDATADIR"
+  mkdir -p "$LOCALDATADIR"
   find "$1" -type f -name "$DECORATION_FILENAME" -print0 |
-    xargs -0 -P 4 $JQ '.releaseid+"\t"+input_filename' |
-    tee "$LOCALDATA_RELEASES" |
-    cut -d "$(printf '\t')" -f 1 >"$tmpreleases"
-  __batch_load_missing "$TYPE_RELEASE" "$tmpreleases"
-  # Get release groups and album artists
-  while IFS= read -r rid; do
-    mb=$(mb_release "$rid")
-    echo "$mb" | $JQ '."release-group".id' >>"$LOCALDATA_RELEASEGROUPS"
-    echo "$mb" | $JQ '."release-group"."artist-credit" | map(.artist.id) | join("\n")' >>"$LOCALDATA_ARTISTS"
-  done <"$tmpreleases"
-  tf=$(mktemp)
-  sort "$LOCALDATA_RELEASEGROUPS" | uniq >"$tf" && mv "$tf" "$LOCALDATA_RELEASEGROUPS"
-  sort "$LOCALDATA_ARTISTS" | uniq >"$tf" && mv "$tf" "$LOCALDATA_ARTISTS"
-  # Populate cache with missing data
-  __batch_load_missing "$TYPE_RELEASEGROUP" "$LOCALDATA_RELEASEGROUPS"
-  __batch_load_missing "$TYPE_ARTIST" "$LOCALDATA_ARTISTS"
-  rm -f "$tmpreleases"
-  info "Resetting views"
-  rm -f "$LOCALDATA_ARTISTS_VIEW" "$LOCALDATA_RELEASEGROUPS_VIEW" "$LOCALDATA_RELEASES_VIEW"
-  precompute_view
+    xargs -0 $JQ '.releaseid+"\t"+input_filename' >"$LOCALDATA_RELEASES"
+  # Get necessary metadata and setup lists
+  tmpreleases=$(mktemp)
+  cut -d "$(printf '\t')" -f 1 "$LOCALDATA_RELEASES" |
+    tee "$tmpreleases" |
+    __batch_load_missing "$TYPE_RELEASE"
+  tmpreleasefiles=$(mktemp)
+  cache_get_file_batch "$TYPE_RELEASE" <"$tmpreleases" >"$tmpreleasefiles"
+  xargs \
+    $JQ '."release-group".id' \
+    <"$tmpreleasefiles" >"$LOCALDATA_RELEASEGROUPS"
+  xargs \
+    $JQ '."release-group"."artist-credit" | map(.artist.id) | join("\n")' \
+    <"$tmpreleasefiles" >"$LOCALDATA_ARTISTS"
+  rm -f "$tmpreleases" "$tmpreleasefiles"
+  tf1=$(mktemp)
+  tf2=$(mktemp)
+  sort "$LOCALDATA_RELEASEGROUPS" | uniq >"$tf1"
+  mv "$tf1" "$LOCALDATA_RELEASEGROUPS"
+  sort "$LOCALDATA_ARTISTS" | uniq >"$tf2"
+  mv "$tf2" "$LOCALDATA_ARTISTS"
+  __batch_load_missing "$TYPE_RELEASEGROUP" <"$LOCALDATA_RELEASEGROUPS"
+  __batch_load_missing "$TYPE_ARTIST" <"$LOCALDATA_ARTISTS"
+  __precompute_lists
+}
+
+# Check if necessary cache files are present or not
+#
+# This method returns a non-zero value if some cached file is required to exist
+# for the computation of the lists (and views). This does not include the
+# derivation of the MusicBrainz artist IDs and MusicBrainz release-group IDs
+# from the MusicBrainz releases (see the `reloaddb` method above).
+local_files_present() {
+  cache_get_file_batch "$TYPE_ARTIST" <"$LOCALDATA_ARTISTS" | xargs ls >/dev/null 2>&1 || return 1
+  cache_get_file_batch "$TYPE_RELEASEGROUP" <"$LOCALDATA_RELEASEGROUPS" | xargs ls >/dev/null 2>&1 || return 1
+  #cut -d "$(printf '\t')" -f 1 "$LOCALDATA_RELEASES" | cache_get_file_batch "$TYPE_RELEASE" | xargs ls >/dev/null 2>&1 || return 1
+  return 0
+}
+
+# Load missing files
+#
+# If missing files were detected with `local_files_present`, then these missing
+# files may be cached using the present method.
+load_missing_files() {
+  __batch_load_missing "$TYPE_ARTIST" <"$LOCALDATA_ARTISTS"
+  __batch_load_missing "$TYPE_RELEASEGROUP" <"$LOCALDATA_RELEASEGROUPS"
+  #cut -d "$(printf '\t')" -f 1 "$LOCALDATA_RELEASES" | __batch_load_missing "$TYPE_RELEASE"
 }

src/sh/log.sh

@@ -1,15 +1,32 @@
 # Logging methods
-ERR="\033[38;5;196m"
-INFO="\033[38;5;75m"
-OFF="\033[m"
-LOGDIR="$HOME/.local/state/$APP_NAME"
-[ -d "$LOGDIR" ] || mkdir -p "$LOGDIR"
-LOGFILE="$LOGDIR/log"
+#
+# The default log file is `LOGFILE`. In the future, this file may become
+# configurable.
+if [ ! "${LOG_LOADED:-}" ]; then
+  ERR="\033[38;5;196m"
+  INFO="\033[38;5;75m"
+  OFF="\033[m"
+  LOGDIR="$HOME/.local/state/$APP_NAME"
+  [ -d "$LOGDIR" ] || mkdir -p "$LOGDIR"
+  LOGFILE="$LOGDIR/log"
+  export ERR INFO OFF LOGFILE
 
+  export LOG_LOADED=1
+fi
+
+# Print an error message to stderr and log it incuding the time stamp and PID
+# to the log file.
 err() {
   echo "$(date) [$$]>${ERR}ERROR:${OFF} ${1:-}" | tee -a "$LOGFILE" | cut -d ">" -f 2- >/dev/stderr
 }
 
+# Print information to stderr and log it incuding the time stamp and PID to the
+# log file.
 info() {
   echo "$(date) [$$]>${INFO}Info:${OFF} ${1:-}" | tee -a "$LOGFILE" | cut -d ">" -f 2- >/dev/stderr
 }
+
+# Like `info` but without newlnes on stderr.
+infonn() {
+  echo "$(date) [$$]>${INFO}Info:${OFF} ${1:-}" | tee -a "$LOGFILE" | cut -d ">" -f 2- | tr '\n' ' ' >/dev/stderr
+}

src/sh/mb.sh

@@ -1,7 +1,13 @@
-# The only IDs uses here are MusicBrainz IDs
+# This files provides a high-level access to the MusicBrainz databse. The only
+# IDs used here are MusicBrainz IDs
 
-# Helper methods to retrieve from cache, if it exists, and otherwise populate
-# cache and retrieve
+# The following methods are local methods that combines the MusicBrainz API
+# with the caching methods.
+
+# Retrieve MusicBrainz data for artist from cache (if it exists), and otherwise
+# download it using the MusicBrainz API.
+#
+# @argument $1: MusicBrainz artist ID
 __mb_artist_cache_or_fetch() {
   if ! cache_get_artist "$1"; then
     api_mb_artist "$1" | cache_put_artist "$1"
@@ -9,6 +15,10 @@ __mb_artist_cache_or_fetch() {
   fi
 }
 
+# Retrieve MusicBrainz data for release group from cache (if it exists), and
+# otherwise download it using the MusicBrainz API.
+#
+# @argument $1: MusicBrainz release-group ID
 __mb_releasegroup_cache_or_fetch() {
   if ! cache_get_releasegroup "$1"; then
     api_mb_releasegroup "$1" | cache_put_releasegroup "$1"
@@ -16,6 +26,10 @@ __mb_releasegroup_cache_or_fetch() {
   fi
 }
 
+# Retrieve MusicBrainz data for release from cache (if it exists), and
+# otherwise download it using the MusicBrainz API.
+#
+# @argument $1: MusicBrainz release ID
 __mb_release_cache_or_fetch() {
   if ! cache_get_release "$1"; then
     api_mb_release "$1" | cache_put_release "$1"
@@ -23,6 +37,10 @@ __mb_release_cache_or_fetch() {
   fi
 }
 
+# Retrieve MusicBrainz data for release groups of given artist from cache (if
+# it exists), and otherwise download it using the MusicBrainz API.
+#
+# @argument $1: MusicBrainz artist ID
 __mb_artist_cache_or_fetch_releasegroups() {
   if ! cache_get_artist_releasegroups "$1"; then
     api_mb_browse_artist_releasegroups "$1" | cache_put_artist_releasegroups "$1"
@@ -39,6 +57,10 @@ __mb_artist_cache_or_fetch_releasegroups() {
   fi
 }
 
+# Retrieve MusicBrainz data for releases of given release group from cache (if
+# it exists), and otherwise download it using the MusicBrainz API.
+#
+# @argument $1: MusicBrainz release-group ID
 __mb_releasegroup_cache_or_fetch_releases() {
   if ! cache_get_releasegroup_releases "$1"; then
     api_mb_browse_releasegroup_releases "$1" | cache_put_releasegroup_releases "$1"
@@ -55,14 +77,18 @@ __mb_releasegroup_cache_or_fetch_releases() {
   fi
 }
 
-# Get MusicBrainz json for artist
-# @argument $1: MusicBrainz Artist ID
+# The following methods provide the external interface
+
+# Retrieve MusicBrainz data for artist
+#
+# @argument $1: MusicBrainz artist ID
 mb_artist() {
   __mb_artist_cache_or_fetch "$1"
 }
 
-# Get Wikidata json for artist
-# @argument $1: MusicBrainz Artist ID
+# Retrieve Wikidata data for artist
+#
+# @argument $1: MusicBrainz artist ID
 mb_artist_wikidata() {
   if ! cache_get_artist_wikidata "$1"; then
     wikidataid=$(mb_artist "$1" |
@@ -76,8 +102,9 @@ mb_artist_wikidata() {
   fi
 }
 
-# Get Wikipedia (English) summary json for artist
-# @argument $1: MusicBrainz Artist ID
+# Retrieve Wikipedia (English) summary json for artist
+#
+# @argument $1: MusicBrainz artist ID
 mb_artist_enwikipedia() {
   if ! cache_get_artist_enwikipedia "$1"; then
     # To fetch the wikipedia data, we need the wikipedia URL
@@ -97,8 +124,9 @@ mb_artist_enwikipedia() {
   fi
 }
 
-# Get Discogs json for artist
-# @argument $1: MusicBrainz Artist ID
+# Retrieve  Discogs json for artist
+#
+# @argument $1: MusicBrainz artist ID
 mb_artist_discogs() {
   if ! cache_get_artist_discogs "$1"; then
     discogsid=$(mb_artist "$1" |
@@ -112,22 +140,131 @@ mb_artist_discogs() {
   fi
 }
 
-# Get release-groups json for artist
-# @argument $1: MusicBrainz Artist ID
+# Retrieve release groups for artist
+#
+# @argument $1: MusicBrainz artist ID
 mb_artist_releasegroups() {
   __mb_artist_cache_or_fetch_releasegroups "$1"
 }
 
-# Get MusicBrainz json for release group
-# @argument $1: MusicBrainz Release-Group ID
+# Retrieve MusicBrainz release group
+#
+# @argument $1: MusicBrainz release-group ID
 mb_releasegroup() {
   __mb_releasegroup_cache_or_fetch "$1"
 }
 
+# Retrieve MusicBrainz releases of release group
+#
+# @argument $1: MusicBrainz release-group ID
 mb_releasegroup_releases() {
   __mb_releasegroup_cache_or_fetch_releases "$1"
 }
 
+# Retrieve MusicBrainz release
+#
+# @argument $1: MusicBrainz release ID
 mb_release() {
   __mb_release_cache_or_fetch "$1"
 }
+
+# Reload hook that is used after a change in the query (when searching
+# MusicBrainz).
+#
+# This method waits for the search to complete, then it parses the search
+# results and prints them.
+mb_results_async() {
+  # Wait for async. process to terminate
+  sleep 1
+  while [ -f "$LOCKFILE" ]; do
+    sleep 1
+  done
+  # Show results
+  column -t -s "$(printf '\t')" "$RESULTS" |
+    sed 's| \+\([0-9a-f-]\+\) \+\([0-9a-f-]\+\)$|\t\1\t\2|'
+}
+
+# Initiate search on MusicBrainz
+#
+# @argument $1: view
+#
+# This methods initiates an asynchronous search for both views
+# (VIEW_SEARCH_ARTIST and VIEW_SEARCH_ALBUM). If a running query is detected,
+# that one is killed first. The search results are then stored and become
+# retrievable using `mb_results_async`.
+mb_search_async() {
+  view="$1"
+  # Kill any running search
+  if [ -f "$PIDFILE" ]; then
+    pid=$(cat "$PIDFILE")
+    rm -f "$PIDFILE"
+    kill -9 "$pid" >/dev/null 2>&1 || true
+  fi
+  # Stop, if no search string is given
+  [ "$FZF_QUERY" ] || exit 0
+  # Store PID of current process
+  echo "$$" >"$PIDFILE"
+  touch "$LOCKFILE"
+  sleep 1
+  if [ "$view" = "$VIEW_SEARCH_ARTIST" ]; then
+    api_mb_search_artist "$FZF_QUERY" |
+      $JQ '.artists[] | [
+    .id,
+    .type,
+    .name,
+    .disambiguation,
+    .["life-span"].begin,
+    .["life-span"].end
+    ] | join("\t")' |
+      awk \
+        -F "\t" \
+        -v file_local_artists="${LOCALDATA_ARTISTS:-}" \
+        -v format_person="$AV_PERSON" \
+        -v format_group="$AV_GROUP" \
+        -v format_disambiguation="$AV_DISAMBIGUATION" \
+        -v format_local="$FORMAT_LOCAL" \
+        "$AWK_ARTISTS" >"$RESULTS" ||
+      true
+  else
+    api_mb_search_releasegroup "$FZF_QUERY" |
+      $JQ '."release-groups"[] | [
+    .id,
+    ."primary-type",
+    (."secondary-types" // []|join(";")),
+    ."first-release-date",
+    .title,
+    (."artist-credit" | map(([.name, .joinphrase]|join(""))) | join(""))
+    ] | join("\t")' |
+      awk \
+        -F "\t" \
+        -v file_local_releasegroups="${LOCALDATA_RELEASEGROUPS:-}" \
+        -v format_release="$RGV_RELEASE" \
+        -v format_release_w_artist="$RGV_RELEASE_W_ARTIST" \
+        -v format_year="$RGV_YEAR" \
+        -v format_album="$FORMAT_TYPE_ALBUM" \
+        -v format_single="$FORMAT_TYPE_SINGLE" \
+        -v format_ep="$FORMAT_TYPE_EP" \
+        -v format_broadcast="$FORMAT_TYPE_BROADCAST" \
+        -v format_other="$FORMAT_TYPE_OTHER" \
+        -v format_has_secondary="$FORMAT_TYPE_HAS_SECONDARY" \
+        -v format_secondary="$FORMAT_TYPE_SECONDARY" \
+        -v format_compilation="$FORMAT_TYPE_SECONDARY_COMPILATION" \
+        -v format_soundtrack="$FORMAT_TYPE_SECONDARY_SOUNDTRACK" \
+        -v format_spokenword="$FORMAT_TYPE_SECONDARY_SPOKENWORD" \
+        -v format_interview="$FORMAT_TYPE_SECONDARY_INTERVIEW" \
+        -v format_audiobook="$FORMAT_TYPE_SECONDARY_AUDIOBOOK" \
+        -v format_audiodrama="$FORMAT_TYPE_SECONDARY_AUDIODRAMA" \
+        -v format_live="$FORMAT_TYPE_SECONDARY_LIVE" \
+        -v format_remix="$FORMAT_TYPE_SECONDARY_REMIX" \
+        -v format_djmix="$FORMAT_TYPE_SECONDARY_DJMIX" \
+        -v format_mixtape="$FORMAT_TYPE_SECONDARY_MIXTAPE" \
+        -v format_demo="$FORMAT_TYPE_SECONDARY_DEMO" \
+        -v format_fieldrec="$FORMAT_TYPE_SECONDARY_FIELDREC" \
+        -v format_local="$FORMAT_LOCAL" \
+        "$AWK_RELEASEGROUPS" |
+      cut -d "$(printf '\t')" -f 2- >"$RESULTS" ||
+      true
+  fi
+  # Process ends now: Display and quit
+  rm -f "$LOCKFILE" "$PIDFILE"
+}

src/sh/mpv.sh

@@ -1,53 +1,104 @@
+# Interface to the mpv music player. This interface communicates to an mpv
+# instance through the socket `MPV_SOCKET`.
+
+# Internal helper method to send a command without arguments to mpv
+#
+# @argument $1: command
 __mpv_command() {
   printf "{ \"command\": [\"%s\"] }\n" "$1" | $SOCAT - "$MPV_SOCKET"
 }
 
+# Internal helper method to send a command with a single argument to mpv
+#
+# @argument $1: command
+# @argument $2: argument
 __mpv_command_with_arg() {
   printf "{ \"command\": [\"%s\", \"%s\"] }\n" "$1" "$2" | $SOCAT - "$MPV_SOCKET"
 }
 
+# Internal helper method to send a command with two arguments to mpv
+#
+# @argument $1: command
+# @argument $2: argument 1
+# @argument $3: argument 2
 __mpv_command_with_args2() {
   printf "{ \"command\": [\"%s\", \"%s\", \"%s\"] }\n" "$1" "$2" "$3" | $SOCAT - "$MPV_SOCKET"
 }
 
+# Internal helper method to resolve mpv variables
+#
+# @argument $1: mpv expression
 __mpv_get() {
   __mpv_command_with_arg "expand-text" "$1" | $JQ '.data'
 }
 
+# Get the total number of tracks in the playlist
 mpv_playlist_count() {
   __mpv_get '${playlist-count}'
 }
 
+# Get the position of the current track in the playlist (0 based)
 mpv_playlist_position() {
   __mpv_get '${playlist-pos}'
 }
 
+# Move track on playlist
+#
+# @argument $1: track index 1
+# @argument $2: track index 2
+#
+# Moves the track at the first index to the position of the track of the second
+# index. Also here, indices are 0 based.
 mpv_playlist_move() {
   __mpv_command_with_args2 "playlist-move" "$1" "$2" >>/tmp/foo
 }
 
+# Remove all tracks from the playlist
 mpv_playlist_clear() {
   __mpv_command "playlist-clear"
 }
 
+# Randomly shuffle the order of the tracks in the playlist
+mpv_playlist_shuffle() {
+  __mpv_command "playlist-shuffle"
+}
+
+# Revert a previously shuffle command
+#
+# This method works only for a first shuffle.
+mpv_playlist_unshuffle() {
+  __mpv_command "playlist-unshuffle"
+}
+
+# Quit the mpv instance bound to the socket `MPV_SOCKET`
 mpv_quit() {
   __mpv_command "quit"
 }
 
+# Start an mpv instance and bind it to the socket `MPV_SOCKET`
 mpv_start() {
   MPV_SOCKET="$(mktemp --suffix=.sock)"
   trap 'mpv_quit >/dev/null; rm -f "$MPV_SOCKET"' EXIT INT
   $MPV --no-config --no-terminal --input-ipc-server="$MPV_SOCKET" --idle --no-osc --no-input-default-bindings &
 }
 
+# Play the track at the specified index in the playlist
+#
+# @argument $1: index (0 based)
 mpv_play_index() {
   __mpv_command_with_arg "playlist-play-index" "$1"
 }
 
+# Remove the track at the specified index from the playlist
+#
+# @argument $1: index (0 based)
 mpv_rm_index() {
   __mpv_command_with_arg "playlist-remove" "$1"
 }
 
+# Load the playlist with the specified list, and start playing
+#
+# This method reads from stdin a playlist file, e.g., a .m3u file.
 mpv_play_list() {
   t=$(mktemp)
   cat >"$t"
@@ -55,6 +106,9 @@ mpv_play_list() {
   rm -f "$t"
 }
 
+# Append the playlist with the specified list, and start playing
+#
+# This method reads from stdin a playlist file, e.g., a .m3u file.
 mpv_queue_list() {
   t=$(mktemp)
   cat >"$t"
@@ -62,6 +116,10 @@ mpv_queue_list() {
   rm -f "$t"
 }
 
+# Insert the playlist with the specified list as the next item, and start
+# playing
+#
+# This method reads from stdin a playlist file, e.g., a .m3u file.
 mpv_queue_next_list() {
   t=$(mktemp)
   cat >"$t"
@@ -78,22 +136,27 @@ mpv_queue_next_list() {
   done
 }
 
+# Play next track on playlist
 mpv_next() {
   __mpv_command "playlist-next"
 }
 
+# Play previous track on playlist
 mpv_prev() {
   __mpv_command "playlist-prev"
 }
 
+# Seek forward by 10 seconds
 mpv_seek_forward() {
   __mpv_command_with_arg "seek" "10"
 }
 
+# Seek backward by 10 seconds
 mpv_seek_backward() {
   __mpv_command_with_arg "seek" "-10"
 }
 
+# Pause if mpv plays, and play if it is paused
 mpv_toggle_pause() {
   __mpv_command_with_arg "cycle" "pause"
 }

src/sh/playback.sh

@@ -4,16 +4,24 @@
 # a higher-level playback functionality is provided.
 
 # Available playback commands
-PLAYBACK_CMD_PLAY="play"
-PLAYBACK_CMD_QUEUE="queue"
-PLAYBACK_CMD_QUEUE_NEXT="queue-next"
-PLAYBACK_CMD_TOGGLE_PLAYBACK="toggle"
-PLAYBACK_CMD_PLAY_NEXT="next"
-PLAYBACK_CMD_PLAY_PREV="prev"
-PLAYBACK_CMD_SEEK_FORWARD="seekf"
-PLAYBACK_CMD_SEEK_BACKWARD="seekb"
+if [ ! "${PLAYBACK_LOADED:-}" ]; then
+  PLAYBACK_CMD_PLAY="play"
+  PLAYBACK_CMD_QUEUE="queue"
+  PLAYBACK_CMD_QUEUE_NEXT="queue-next"
+  PLAYBACK_CMD_TOGGLE_PLAYBACK="toggle"
+  PLAYBACK_CMD_PLAY_NEXT="next"
+  PLAYBACK_CMD_PLAY_PREV="prev"
+  PLAYBACK_CMD_SEEK_FORWARD="seekf"
+  PLAYBACK_CMD_SEEK_BACKWARD="seekb"
+  export PLAYBACK_CMD_PLAY PLAYBACK_CMD_QUEUE PLAYBACK_CMD_QUEUE_NEXT \
+    PLAYBACK_CMD_TOGGLE_PLAYBACK PLAYBACK_CMD_PLAY_NEXT \
+    PLAYBACK_CMD_PLAY_PREV PLAYBACK_CMD_SEEK_FORWARD PLAYBACK_CMD_SEEK_BACKWARD
+
+  export PLAYBACK_LOADED=1
+fi
 
 # Obtain playback command from key press
+#
 # @argument $1: key
 __playback_cmd_from_key() {
   key=$1
@@ -36,9 +44,10 @@ __playback_cmd_from_key() {
 }
 
 # Generate playlist from MB release ID and path to decoration
-# @argument $1: MusicBrainz Release ID
+#
+# @argument $1: MusicBrainz release ID
 # @argument $2: Path to decoration file
-# @argument $3: MusicBrainz Track ID to select (optional)
+# @argument $3: MusicBrainz track ID to select (optional)
 __generate_playlist() {
   printf "#EXTM3U\n"
   dir="$(dirname "$2")"
@@ -66,7 +75,7 @@ __generate_playlist() {
           (."artist-credit" | map([.name, .joinphrase] | join("")) | join("")),
           $deco
           ] | join("\t"),
-          length: (.length / 1000 | round | tostring),
+          length: (.length // 0 / 1000 | round | tostring),
           $pos,
           number: .number,
           file: $filenames[.id]
@@ -92,7 +101,6 @@ playback() {
   mbid="${3:-}"
   path="${4:-}"
   pbcmd=$(__playback_cmd_from_key "$FZF_KEY")
-  info "playback(): view=$view; mbid_current=$mbid_current; mbid=$mbid; path=$path; pbcmd=$pbcmd"
   case "$pbcmd" in
   "$PLAYBACK_CMD_PLAY")
     [ "$path" ] || exit 0

src/sh/playlist.sh

@@ -1,9 +1,22 @@
-PLAYLIST_CMD_REMOVE="rm"
-PLAYLIST_CMD_UP="up"
-PLAYLIST_CMD_DOWN="down"
-PLAYLIST_CMD_CLEAR="clear"
-PLAYLIST_CMD_CLEAR_ABOVE="clear-above"
-PLAYLIST_CMD_CLEAR_BELOW="clear-below"
+# Playlist manipulation
+#
+# This files provides an interface to manipulate the playlist. The available
+# commands are defined in the following variables.
+if [ ! "${PLAYLIST_LOADED:-}" ]; then
+  PLAYLIST_CMD_REMOVE="rm"
+  PLAYLIST_CMD_UP="up"
+  PLAYLIST_CMD_DOWN="down"
+  PLAYLIST_CMD_CLEAR="clear"
+  PLAYLIST_CMD_CLEAR_ABOVE="clear-above"
+  PLAYLIST_CMD_CLEAR_BELOW="clear-below"
+  PLAYLIST_CMD_SHUFFLE="shuffle"
+  PLAYLIST_CMD_UNSHUFFLE="unshuffle"
+  export PLAYLIST_CMD_REMOVE PLAYLIST_CMD_UP PLAYLIST_CMD_DOWN \
+    PLAYLIST_CMD_CLEAR PLAYLIST_CMD_CLEAR_ABOVE PLAYLIST_CMD_CLEAR_BELOW \
+    PLAYLIST_CMD_SHUFFLE PLAYLIST_CMD_UNSHUFFLE
+
+  export PLAYLIST_LOADED=1
+fi
 
 # Run playback commands
 #
@@ -17,16 +30,18 @@ playlist() {
   "$PLAYLIST_CMD_DOWN") mpv_playlist_move $((FZF_POS - 0)) $((FZF_POS - 1)) ;;
   "$PLAYLIST_CMD_CLEAR") mpv_playlist_clear ;;
   "$PLAYLIST_CMD_CLEAR_ABOVE")
-    for i in $(seq "$FZF_POS"); do
+    for _ in $(seq "$FZF_POS"); do
       mpv_rm_index 0
     done
     ;;
   "$PLAYLIST_CMD_CLEAR_BELOW")
     cnt=$(mpv_playlist_count)
     rem=$((cnt - FZF_POS + 1))
-    for i in $(seq "$rem"); do
+    for _ in $(seq "$rem"); do
       mpv_rm_index $((FZF_POS - 1))
     done
     ;;
+  "$PLAYLIST_CMD_SHUFFLE") mpv_playlist_shuffle ;;
+  "$PLAYLIST_CMD_UNSHUFFLE") mpv_playlist_unshuffle ;;
   esac
 }

src/sh/preview.sh

@@ -1,10 +1,19 @@
+# Preview methods
+#
+# For now, only artist previews are supported.
+
+# This internal method reshapes the text to be shown in the preview. This
+# creates a border on both horizontal ends.
+#
+# The text is read from stdin.
 __shape() {
   cat | tr -d '\r' | fold -s -w "$((FZF_PREVIEW_COLUMNS - 4))" | awk '{print "  "$0"  "}'
 }
 
 # Print preview of artist
-# @input $1: MusicBrainz Artist ID
-__preview_artist() {
+#
+# @input $1: MusicBrainz artist ID
+preview_artist() {
   desc=$(mb_artist_enwikipedia "$1" | $JQ '.extract' | __shape)
   [ "$desc" ] || desc=$(mb_artist_discogs "$1" | $JQ '.profile' | sed 's/\[a=\([^]]*\)\]/\1/g' | __shape)
   if [ "$(mb_artist "$1" | $JQ '.type')" = "Person" ]; then
@@ -37,3 +46,8 @@ __preview_artist() {
   #link=$(printf "More info:\033]8;;%s\033\\ %s\033]8;;\033\\" "https://musicbrainz.org/" "[MusicBrainz]")
   printf "$APV_FORMAT" "$desc" "${lifespan:-}"
 }
+
+# Print message if there is nothing to be shown
+preview_nothing() {
+  echo "No preview available."
+}

src/sh/query.sh

@@ -25,11 +25,16 @@
 # - q_single: Release group is of type single
 # - q_official: Release is official
 
+# Clean a filter string
+#
+# This method reads from stdin a string and removes all colors and escapes
+# white spaces.
 __clean_filter() {
   cat | sed "s/${ESC}\[[0-9;]*[mK]//g" | sed "s/ /\\\ /g"
 }
 
 # Determine preset query
+#
 # @argument $1: Current view
 # @argument $2: Key pressed (optional)
 #

src/sh/theme.sh

@@ -6,15 +6,19 @@
 
 # Colors (internal only)
 ESC=$(printf '\033')
+BOLD="${ESC}[1m"
 FAINT="${ESC}[2m"
+UNDERLINE="${ESC}[4m"
 CARTIST="${ESC}[38;5;209m"
 CTITLE="${ESC}[38;5;229m"
+CRELINFO="${ESC}[38;5;179m"
 CYEAR="${ESC}[38;5;179m"
 CDISAMB="$FAINT${ESC}[38;5;172m"
 CNOTE="${ESC}[38;5;242m"
 CXXX="${ESC}[38;5;109m"
 CDESC="${ESC}[38;5;254m"
 CLIFE="${ESC}[38;5;251m"
+CKB="${ESC}[38;5;224m"
 OFF="${ESC}[m"
 
 # Pointers
@@ -25,24 +29,24 @@ FORMAT_LOCAL="${FORMAT_LOCAL:-"🔆"}"
 FORMAT_CURRENT="${FORMAT_CURRENT:-"👉"}"
 export FORMAT_LOCAL FORMAT_CURRENT
 
-# Input prompts
+# Input prompt
 # =============
-# General search prompt
+# Search prompt
 SEARCH_PROMPT=${SEARCH_PROMPT:-"🔎 〉"}
-# Prompt that takes an artist name as argument
-ARTIST_PROMPT="${ARTIST_PROMPT:-"🎤 ${CARTIST}%s$OFF 〉"}"
-# Prompt that takes an artist name and a release name as arguments (in that
-# order)
-FULL_PROMPT="${FULL_PROMPT:-"🎤 ${CARTIST}%s$OFF 》${CTITLE}%s$OFF 〉"}"
-export SEARCH_PROMPT ARTIST_PROMPT FULL_PROMPT
+export SEARCH_PROMPT
 
-# Visual representation of current mode
-# =====================================
-# Sign to indicate `normal` mode
-PROMPT_NORMAL="${PROMPT_NORMAL:-"${FAINT}[n]${OFF}"}"
-# Sign to indicate `insert` mode
-PROMPT_INSERT="${PROMPT_INSERT:-"${FAINT}[i]${OFF}"}"
-export PROMPT_NORMAL PROMPT_INSERT
+# Headers
+# =======
+# Header that displays artist's name
+HEADER_ARTIST="${HEADER_ARTIST:-"🎤 ${CARTIST}%s$OFF 〉"}"
+# Header that displays the release-group name after artist's
+HEADER_ARTIST_RELEASEGROUP="${HEADER_ARTIST_RELEASEGROUP:-"🎤 ${CARTIST}%s$OFF 》${CTITLE}%s$OFF 〉"}"
+# Header that in addition to `HEADER_ARTIST_RELEASEGROUP` also shows some
+# release information
+HEADER_RELEASE="${HEADER_RELEASE:-"🎤 ${CARTIST}%s$OFF 》${CTITLE}%s$OFF 〉%s"}"
+# The release information is formatted as follows (placeholders implicit):
+HEADER_RELEASE_FORMAT="${HEADER_RELEASE_FORMAT:-"${CRELINFO}<<tracks>> tx <<media>> $OFF|$CRELINFO <<label>> <<country>> <<year>>$OFF"}"
+export HEADER_ARTIST HEADER_ARTIST_RELEASEGROUP HEADER_RELEASE HEADER_RELEASE_FORMAT
 
 # Artist view
 # ===========
@@ -152,3 +156,13 @@ REC_FORMAT="${REC_FORMAT:-"${CNOTE}${FAINT}<<med>>\t${CNOTE}<<nr>>$OFF\t${CTITLE
 # Format of a track in the playlist
 REC_FORMAT_NO_NUMBER="${REC_FORMAT_NO_NUMBER:-"${CTITLE}<<title>>\t${CARTIST}<<artist>>\t${CXXX}<<duration>>$OFF"}"
 export REC_FORMAT REC_FORMAT_NO_NUMBER
+
+# Keybinding themes
+# =================
+# Format keybinding group
+KBF_GROUP="${KBF_GROUP:-"${UNDERLINE}${CKB}%s$OFF"}"
+# Format key
+KBF_KEY="${KBF_KEY:-"${BOLD}${CKB}%s$OFF"}"
+# Format description
+KBF_DESC="${KBF_DESC:-"${CKB}%s$OFF"}"
+export KBF_GROUP KBF_KEY KBF_DESC

src/sh/tools.sh

@@ -1,3 +1,13 @@
+# Load the tools required for this application. The tools are preset with
+# default command-line arguments.
+#
+# List of tools:
+# - fzf:   in order to display, search, and navigate lists
+# - curl:  for API access
+# - jq:    to parse json files
+# - mpv:   music player
+# - socat: to communicate with the socket mpv is bound to
+# - xsel:  to copy content to the clipboard (not necessary)
 if [ ! "${TOOLS_LOADED:-}" ]; then
   if command -v "fzf" >/dev/null; then
     FZF="fzf --black --ansi --cycle --tiebreak=chunk,index"
@@ -39,5 +49,8 @@ if [ ! "${TOOLS_LOADED:-}" ]; then
   fi
   export SOCAT
 
+  command -v "xsel" >/dev/null && CLIP="xsel" || CLIP="true"
+  export CLIP
+
   export TOOLS_LOADED=1
 fi