improvement: consistent use of delimiter

- collection label before time
- UTF8 arrow insead of `->`

README.md

@@ -1,4 +1,7 @@
 A [fzf](https://github.com/junegunn/fzf)-based **calendar** application with CalDav support.
+If you are interested in this, then you may also be interested in the
+corresponding journaling application
+[fzf-vjour](https://github.com/baumea/fzf-vjour).
 
 Description and Use Case
 ------------------------
@@ -60,37 +63,81 @@ item_types = ["VEVENT"]
 ...
 ```
 
+Here is the complete list of configuration options:
+
+```
+###   ROOT:                 Directory containing the collections
+###   COLLECTION_LABELS:    Mappings between collections and labels
+###   SYNC_CMD (optional):  Synchronization command
+###   DAY_START (optional): Hour of start of the day (defaults to 8)
+###   DAY_END (optional):   Hour of end of the day (defaults to 18)
+###   EDITOR (optional):    Your favorite editor, is usually already exported
+###   TZ (optional):        Your favorite timezone, usually system's choice
+###   LC_TIME (optional):   Your favorite locale for date and time
+###   ZI_DIR (optional):    Location of tzdata, defaults to /usr/share/zoneinfo
+```
+
 Usage
 -----
-Use the default `fzf` keys to navigate your calendar entries, e.g., `ctrl-j`
-and `ctrl-k` for going down/up in the list.
 After starting `fzf-vcal`, you are presented with a view on the current week.
+You can navigate that week using `j` and `h` for going down and up.
 Hit `<enter>` on any day, and you will see all entries for that date, including
 previews. In both, the week and day views, you can add entries by hitting
 `ctrl-n`. 
 
-Here is the list of available keybindings:
+Here is the list of all available keybindings:
-| Key | View | Action |
+
-| --- | ---- | ------ |
+### Week view
-| `enter` | week view | Switch to day view |
+
-| `ctrl-n` | week view | Make a new entry |
+| Key | Action |
-| any letter | week view | Search in the list of all entries |
+| --- | ------ |
-| `backspace` on empty query | week view | Undo search |
+| `q` | quit |
-| `ctrl-u` | week view | Go back one week |
+| `enter` | open day |
-| `ctrl-d` | week view | Go forth one week |
+| `j` | down |
-| `ctrl-alt-u` | week view | Go back one month |
+| `k` | up |
-| `ctrl-alt-d` | week view | Go forth one month |
+| `l` | go to next week |
-| `ctrl-s` | week view | Run the synchronization command |
+| `h` | go to previous week |
-| `ctrl-l` | week view | Go to current week |
+| `ctrl-l` | go to next month |
-| `ctrl-g` | week view | Goto date |
+| `ctrl-h` | go to previous month |
-| `enter` | day view | Open selected  calendar entry in your favorite `$EDITOR` |
+| `alt-l` | go to next year |
-| `ctrl-n` | day view | Make a new entry |
+| `alt-h` | go to previous year |
-| `esc`, `backspace` or `q` | day view | Go back to week view |
+| `ctrl-r` | reload and go to week that contains `today` |
-| `ctrl-s` | day view | Run the synchronization command |
+| `ctrl-g` | interactively go to specified week |
-| `ctrl-alt-d` | day view | Delete selected entry |
+| `ctrl-t` | set timezon |
-| `j` | day view | Scroll down in preview window |
+| `ctrl-s` | synchronize |
-| `k` | day view | Scroll up in preview window |
+| `ctrl-n` | add new entry |
-| `w` | day view | Toggle line wrap in preview window ||
+| `\` | search all appointment s |
+| `x` | Cancel and confirm entry |
+| `c` | Unconfirm and confirm entry |
+
+### Day view
+
+| Key | Action |
+| --- | ------ |
+| `enter` | edit appointment |
+| `a` | open attachment list of appointment |
+| `j` | down |
+| `k` | up |
+| `l` | go to next day |
+| `h` | go to previous day |
+| `ctrl-l` | go to next week |
+| `ctrl-h` | go to previous week |
+| `alt-l` | go to next month |
+| `alt-h` | go to previous month |
+| `ctrl-r` | reload and go to `today` |
+| `ctrl-g` | interactively go to specified day |
+| `ctrl-t` | set timezon |
+| `ctrl-s` | synchronize |
+| `ctrl-n` | add new entry |
+| `ctrl-alt-d` | delete entry |
+| `w` | toggle line wrap in preview |
+| `ctrl-d` | down in preview |
+| `ctrl-u` | up in preview |
+| `alt-v` | view raw iCalendar file |
+| `esc` | return to week view, you can also do this with `q` or `backspace` |
+
+
+### There is more
 
 You may also invoke the script with `--help` to see further command-line options. 
 
@@ -98,6 +145,10 @@ Also, you may set `LC_TIME` to your preferred language, and `TZ` to your
 preferred timezone. The latter is in particular helpful if you want to take a
 look at your calendar relative to being in another timezone.
 
+Git support
+-----------
+You can track your events with `git` by simply running `fzf-vcal --git-init`.
+
 License
 -------
 This project is licensed under the [MIT License](./LICENSE).

scripts/build.sh

@@ -5,7 +5,15 @@ GREEN="\033[0;32m"
 OFF="\033[m"
 NAME="fzf-vcal"
 SRC="./src/main.sh"
-echo "🐔 ${GREEN}Building${OFF} ${BOLD}$NAME${OFF}"
+
-sed -E 's|@@include (.+)$|cat \1|e' "$SRC" >"$NAME"
+tmpdir=$(mktemp -d)
+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 "🥚 ${GREEN}Make executable and cleanup${OFF}"
 chmod +x "$NAME"
-echo "🥚 ${GREEN}Done${OFF}"
+rm -rf "$tmpdir"
+echo "🍳 ${GREEN}Done:${OFF} Sucessfully built ${BOLD}${GREEN}$NAME${OFF}"

src/awk/approx.awk

@@ -0,0 +1,66 @@
+## src/awk/approx.awk
+##
+## Generate single-line approximate information for every iCalendar argument.
+## The fields in each line are separated by "\t"
+## The fields are the following:
+## 1. "~" (constant, indicating that the lines contains approximate information)
+## 2. start (this can be used in date (1))
+## 3. end (this can be used in date (1)
+## 4. string to display
+## 5. filename (collection/name)
+##
+## @assign collection_labels: See configuration of the current program.
+
+@include "lib/awk/icalendar.awk"
+
+# Functions
+
+# Get relative file path.
+#
+# @local variables: n, a
+# @input path: Path to file
+# @return: File path of depth 1
+function fn(path,    n, a) {
+  n = split(path, a, "/")
+  return a[n-1] "/" a[n]
+}
+
+# Generate title string that will be displayed to user. Here, the start date
+# gets a monthly resolution.
+#
+# @input start: Parsed content of DTSTART field
+# @input summary: Content of SUMMARY field
+# @return: colorized single-line title string
+function title(start, summary) {
+  summary = getcontent(summary)
+  gsub("\n",  " ", summary) # This will be put on a single line
+  gsub("\\t", " ", summary) # we use "\t" as delimiter
+  depth = split(FILENAME, path, "/")
+  collection = depth > 1 ? path[depth-1] : ""
+  collection = collection in collection2label ? collection2label[collection] : collection
+  return FAINT "~ " collection " " gensub(/^[^0-9]*([0-9]{4})([0-9]{2}).*$/, "\\1-\\2", "1", start) " " summary OFF
+}
+
+# AWK program
+BEGIN {
+  FS="[:;=]"
+  OFS="\t"
+  split(collection_labels, mapping, ";")
+  for (map in mapping)
+  {
+    split(mapping[map], m, "=")
+    collection2label[m[1]] = m[2]
+  }
+  # Colors
+  FAINT = "\033[2m"
+  OFF = "\033[m"
+}
+BEGINFILE             { inside = 0; rs = 0; dur = 0; summary = ""; start = "ERROR"; end = "ERROR" }
+/^END:VEVENT/         { print "~", start, dur ? start " " end : end, title(start, summary), fn(FILENAME); nextfile }
+/^DTSTART/ && inside  { start = parse() }
+/^DTEND/ && inside    { end = parse() }
+/^DURATION/ && inside { end = parse_duration($NF); dur = 1 }
+/^[^ ]/ && rs         { rs = 0 }
+/^ / && rs            { summary = summary substr($0, 2) }
+/^SUMMARY/ && inside  { rs = 1; summary = $0 }
+/^BEGIN:VEVENT/       { inside = 1 }

src/awk/attach.awk

@@ -0,0 +1,35 @@
+## src/awk/attach.awk
+## Prepend attachment to iCalendar file.
+##
+## @assign file: Path to base64-encoded content
+## @assign mime: Mime
+## @assign filename: Original filename
+
+# Functions
+
+# Write attachment
+#
+# @local variables: line, aline
+function write_attachment(    line, aline, fl) {
+  line = "ATTACH;ENCODING=BASE64;VALUE=BINARY;FMTTYPE="mime";FILENAME="filename":"
+  fl = 1
+  while (getline aline <file) {
+    line = line aline
+    if (fl && length(line) >= 73) {
+      print substr(line, 1, 73)
+      line = substr(line, 74)
+      fl = 0
+    }
+    while (length(line) >= 72) {
+      print " "substr(line, 1, 72)
+      line = substr(line, 73)
+    }
+  }
+  if (line)
+    print " "line
+}
+
+# AWK program
+
+/^END:VEVENT$/ { write_attachment() }
+{ print }

src/awk/attachdd.awk

@@ -0,0 +1,8 @@
+BEGIN                       { FS="[:;]" }
+/^END:VEVENT$/              { ins = 0; exit }
+/^[^ ]/ && a                { a = 0 }
+/^ / && a && p              { print substr($0, 2); }
+/^ / && a && !p             { if (index($0, ":")) { p = 1; print substr($0, index($0, ":")+1) } }
+/^ATTACH/ && ins            { i++; }
+/^ATTACH/ && ins && i == id { a = 1; if (index($0, ":")) { p = 1; print substr($0, index($0, ":")+1) } }
+/^BEGIN:VEVENT$/            { ins = 1 }

src/awk/attachls.awk

@@ -0,0 +1,41 @@
+# Decide if we need to read more to get all properties
+# 
+# @input str: strin read so far
+# @return: 1 if we need more data, 0 otherwise
+function cont_reading(str) {
+  return index(str, ":") ? 0 : 1
+}
+
+# Get information about attachment
+#
+# @input i: Attachment index
+# @input str: Attachment string (at least up to content separator `:`)
+# @return: informative string
+function att_info(i, str,    cnt, k, info) {
+  str = substr(str, 1, index(str, ":") - 1)
+  cnt = split(str, props)
+  if (cnt > 1) {
+    for (k=2; k<=cnt; k++) {
+      pname = substr(props[k], 1, index(props[k], "=") - 1)
+      pvalu = substr(props[k], index(props[k], "=") + 1)
+      if (pname == "ENCODING" && pvalu = "BASE64")
+        enc = "base64"
+      if (pname == "FILENAME")
+        fin = pvalu
+      if (pname == "VALUE")
+        val = pvalu
+      if (pname == "FMTTYPE")
+        type = pvalu
+    }
+    if (enc)
+      info = "inline"
+  }
+  print i, fin, type, enc, info
+}
+
+BEGIN            { FS="[:;]"; OFS="\t" }
+/^END:VEVENT$/   { ins = 0; exit }
+l && !r          { att_info(i, l); l = "" }
+/^ / && r        { l = l substr($0, 2); r = cont_reading($0) }
+/^ATTACH/ && ins { i++; l = $0; r = cont_reading($0) }
+/^BEGIN:VEVENT$/ { ins = 1 }

src/awk/attachrm.awk

@@ -0,0 +1,13 @@
+## src/awk/attachrm.awk
+## Remove attachment from iCalendar file.
+##
+## @assign id: Attachment number to remove
+
+BEGIN                       { FS="[:;]" }
+/^END:VEVENT$/              { ins = 0 }
+/^[^ ]/ && a                { a = 0 }
+/^ / && a                   { next }
+/^ATTACH/ && ins            { i++; }
+/^ATTACH/ && ins && i == id { a = 1; next }
+/^BEGIN:VEVENT$/            { ins = 1 }
+{ print }

src/awk/calannot.awk

@@ -1,3 +1,9 @@
+## src/awk/calannot.awk
+## Annotate monthly calendar
+##
+## @assign cur: Day-of-month to mark as `today`
+## @assign day: Day-of-month to highlight
+
 BEGIN {
   BLACK = "\033[1;30m"
   GREEN = "\033[1;32m"

src/awk/calshift.awk

@@ -0,0 +1,23 @@
+## src/awk/calshift.awk
+## Rearrange days of a monthly output from cal (1), such that Monday is the
+## first day of the week.
+
+BEGIN { 
+  ORS = ""
+  W3 = "   "
+  W17 = W3 W3 W3 W3 W3 "  "
+}
+NR == 1 { i++; print $0 "\n"; next }
+NR == 2 { i++; print substr($0, 4, 17) " " substr($0, 1, 3) " \n"; next }
+NR == 3 && /^ 1/ { print W17; }
+NR == 3 && /^  / { print substr($0, 4, 17); next }
+/[0-9]/ {
+  i++
+  print " " substr($0, 1, 3) " \n" substr($0, 4, 17)
+}
+END { 
+  i++
+  print " " W3 " \n"
+  for (i; i<8; i++)
+    print " " W17 W3 " \n"
+}

src/awk/dayview.awk

@@ -1,26 +1,100 @@
-# 11:00|13:00|1748422800|1748430000|fpath|desc...
+## src/awk/dayview.awk
-# 00:00|00:00|1748296800|1748383200|fpath|desc...
+## Take as input (tab-delimited):
-function allday(desc) {
+##   1. s (start time, as HH:MM)
-  return ITALIC FAINT "    (allday)    " OFF desc
+##   2. e (end time, as HH:MM)
+##   3. starttime
+##   4. endtime
+##   5. fpath
+##   6. collection
+##   7. description
+##   8. status
+##
+## filter out irrelevant lines, and generate the view of a day
+## (tab-delimited), including empty hours:
+##   1. start date
+##   2. start time
+##   3. end time
+##   4. file path
+##   5. collection
+##   6. description
+##
+## @assign today: Date of `today` in the format %D (%m/%d/%y)
+## @assign daystart: Hour of start of the day
+## @assign dayend: Hour of end of the day
+
+# Functions
+
+# Set event color based on status
+
+# @input status: Event status, one of TENTATIVE, CONFIRMED, CANCELLED
+# @return: Color modifier
+function color_from_status(status) {
+  return status == "CANCELLED" ? STRIKE CYAN : status == "TENTATIVE" ? FAINT CYAN : CYAN
 }
-function endstoday(stop, desc) {
+
-  return CYAN "      -- " stop OFF ": " desc
+# Return line for all-day event.
+#
+# @local variables: color
+# @input collection: Collection symbol
+# @input desc: Event description
+# @input status: Event status, one of TENTATIVE, CONFIRMED, CANCELLED
+# @return: Single-line string
+function allday(collection, desc, status,    color) {
+  color = color_from_status(status)
+  return collection " " LIGHT_CYAN ITALIC FAINT "    (allday)   " OFF color desc OFF
 }
-function slice(start, stop, desc) {
+
+# Return line for multi-day event, or event that starts at midnight, which ends today.
+#
+# @local variables: color
+# @input stop: Time at which the event ends
+# @input collection: Collection symbol
+# @input desc: Event description
+# @input status: Event status, one of TENTATIVE, CONFIRMED, CANCELLED
+# @return: Single-line string
+function endstoday(stop, collection, desc, status) {
+  color = color_from_status(status)
+  return collection " " LIGHT_CYAN "      → " stop ": " OFF color desc OFF
+}
+
+# Return line for event that starts sometime today.
+#
+# @local variables: color
+# @input start: Time at which the event starts
+# @input stop: Time at which the event ends
+# @input collection: Collection symbol
+# @input desc: Event description
+# @input status: Event status, one of TENTATIVE, CONFIRMED, CANCELLED
+# @return: Single-line string
+function slice(start, stop, collection, desc, status) {
+  color = color_from_status(status)
   if (stop == "00:00")
-    return CYAN start " --      " OFF ": " desc
+    return collection " " LIGHT_CYAN start " →      " ": " OFF color desc OFF
    else
-    return CYAN start OFF " -- " CYAN stop OFF ": " desc
+    return collection " " LIGHT_CYAN start " – " stop ": " OFF color desc OFF
 }
+
+# Print line for a single hour entry.
+#
+# @input hour: Hour of the entry
 function hrline(hour) {
   hour = hour < 10 ? "0"hour : hour
-  print hour, "", "", "", FAINT hour ":00           ----------------------" OFF
+  print today, hour, "", "", "", "   " FAINT hour ":00          ----------------------" OFF
 }
+
+# Print lines for hour entries before an event that starts at `start` and stops
+# at `stop`.
+#
+# @local variables: starth, stoph, tmp, i
+# @input start: Time at which the event starts
+# @input stop: Time at which the event ends
+# @input h: Last event-free hour
+# @return: Hour of now last event-free hour
 function hrlines(start, stop, h,    starth, stoph, tmp, i) {
   starth = substr(start, 1, 2)
   stoph = substr(stop, 1, 2)
   tmp = substr(start, 4, 2) == "00" ? 0 : 1
-  for (i=h; i < starth + tmp; i++)
+  for (i=h; i < starth + tmp && i < dayend; i++)
     hrline(i)
   tmp = substr(stop, 4, 2) == "00" ? 0 : 1
   if (stoph + tmp < daystart)
@@ -28,23 +102,22 @@ function hrlines(start, stop, h,    starth, stoph, tmp, i) {
   else
     return stoph + tmp
 }
+
+# AWK program
 BEGIN {
-  FS = "|"
+  FS = "\t"
-  GREEN = "\033[1;32m"
+  OFS = "\t"
-  RED = "\033[1;31m"
+  LIGHT_CYAN = "\033[1;36m"
-  WHITE = "\033[1;97m"
   CYAN = "\033[1;36m"
   ITALIC = "\033[3m"
   FAINT = "\033[2m"
+  STRIKE = "\033[9m"
   OFF = "\033[m"
-  OFS = "|"
 }
-$1 == "00:00" && $2 == "00:00" { print $1, $3, $4, $5, allday($6);        next }
+$1 == "00:00" && $2 == "00:00" { print today, $1, $3, $4, $5, allday($6, $7, $8);        next }
-$1 == "00:00"                  { print $1, $3, $4, $5, endstoday($2, $6); next }
+$1 == "00:00"                  { print today, $1, $3, $4, $5, endstoday($2, $6, $7, $8); next }
 $1 ~ /^[0-9]{2}:[0-9]{2}$/     {
-  daystart = hrlines($1, $2, daystart,    starth, stoph, tmp, i)
+  daystart = hrlines($1, $2, daystart)
-  print $1, $3, $4, $5, slice($1, $2, $6)
+  print today, $1, $3, $4, $5, slice($1, $2, $6, $7, $8)
-}
-END {
-  hrlines(dayend":00", 0, daystart,    starth, stoph, tmp, i)
 }
+END                            { hrlines(dayend":00", 0, daystart)                        }

src/awk/get.awk

@@ -1,18 +1,18 @@
-# print content of field `field`
+## src/awk/get.awk
-BEGIN                     { FS = ":"; regex = "^" field; }
+## Print content of a field of an iCalendar file.
+##
+## @assign field: Field name
+
+@include "lib/awk/icalendar.awk"
+
+BEGIN              { FS = ":"; regex = "^" field }
 /^BEGIN:VEVENT$/   { inside = 1 }
 /^END:VEVENT$/     { exit }
-$0 ~ regex                { content = $0;                    next; }
+$0 ~ regex         { content = $0; next }
-/^ / && content           { content = content substr($0, 2); next; }
+/^ / && content    { content = content substr($0, 2); next }
 /^[^ ]/ && content { exit }
 END {
   if (!inside) { exit }
   # Process content line
-  content = substr(content, index(content, ":") + 1);
+  print getcontent(content)
-  gsub("\\\\n",    "\n", content);
-  gsub("\\\\N",    "\n", content);
-  gsub("\\\\,",    ",",  content);
-  gsub("\\\\;",    ";",  content);
-  gsub("\\\\\\\\", "\\", content);
-  print content;
 }

src/awk/has.awk

@@ -0,0 +1,10 @@
+## src/awk/has.awk
+## Decide if VEVENT file has a specific field.
+##
+## @assign field: Field name
+
+# AWK program
+BEGIN              { FS = "[:;]" }
+/^BEGIN:VEVENT$/   { ins = 1 }
+/^END:VEVENT$/     { exit 1 }
+ins && $1 == field { exit 0 }

src/awk/lines.awk

@@ -1,79 +0,0 @@
-function parse(    dt) {
-  # Get timezone information
-  dt = "";
-  for (i=2; i<NF-1; i+=2) {
-    if ($i == "TZID") {
-      dt = "TZ=\"" $(i+1) "\" ";
-      break;
-    }
-  }
-  # Get date/datetime
-  return length($NF) == 8 ?
-    dt $NF :
-    dt gensub(/^([0-9]{8})T([0-9]{2})([0-9]{2})([0-9]{2})(Z)?$/, "\\1 \\2:\\3:\\4\\5", "g", $NF);
-}
-
-function parse_duration(    dt, dta, i, n, a, seps) {
-  n = split($NF, a, /[PTWHMSD]/, seps);
-  delete dta;
-  for (i=2; i<=n; i++) {
-    if(seps[i] == "W") dta["weeks"]   = a[i];
-    if(seps[i] == "H") dta["hours"]   = a[i];
-    if(seps[i] == "M") dta["minutes"] = a[i];
-    if(seps[i] == "S") dta["seconds"] = a[i];
-    if(seps[i] == "D") dta["days"]    = a[i];
-  }
-  dt = a[1] ? a[1] : "+";
-  for (i in dta) {
-    dt = dt " " dta[i] " " i;
-  }
-  return dt;
-}
-
-function fn(path,    n, a) {
-  n = split(path, a, "/");
-  return a[n-1] "/" a[n];
-}
-
-function title(start, summary) {
-  summary = substr(summary, index(summary, ":") + 1);
-  #gsub("\\\\n",    "\n", summary); # one-liner
-  #gsub("\\\\N",    "\n", summary); # one-liner
-  gsub("\\\\n",    " ",  summary);
-  gsub("\\\\N",    " ",  summary);
-  gsub("\\\\,",    ",",  summary);
-  gsub("\\\\;",    ";",  summary);
-  gsub("\\\\\\\\", "\\", summary);
-  gsub("\\|", ":", summary); # we use "|" as delimiter
-  depth = split(FILENAME, path, "/");
-  collection = depth > 1 ? path[depth-1] : "";
-  collection = collection in collection2label ? collection2label[collection] : collection;
-  return FAINT "~ " collection " " gensub(/^[^0-9]*([0-9]{4})([0-9]{2}).*$/, "\\1-\\2", "1", start) " " summary OFF
-}
-
-BEGIN                 { 
-  FS="[:;=]";
-  OFS="|" 
-  split(collection_labels, mapping, ";");
-  for (map in mapping)
-  {
-    split(mapping[map], m, "=");
-    collection2label[m[1]] = m[2];
-  }
-  # Colors
-  GREEN = "\033[1;32m";
-  RED = "\033[1;31m";
-  WHITE = "\033[1;97m";
-  CYAN = "\033[1;36m";
-  FAINT = "\033[2m";
-  OFF = "\033[m";
-}
-BEGINFILE             { inside = 0; rs = 0; dur = 0; summary = ""; start = "ERROR"; end = "ERROR" }
-/^END:VEVENT/         { print "~", start, dur ? start " " end : end, title(start, summary), fn(FILENAME,    n, a); nextfile }
-/^DTSTART/ && inside  { start = parse(    dt) }
-/^DTEND/ && inside    { end = parse(    dt) }
-/^DURATION/ && inside { end = parse_duration(    dt, dta, i, n, a, seps); dur = 1 }
-/^[^ ]/ && rs         { rs = 0 }
-/^ / && rs            { summary = summary substr($0, 2); }
-/^SUMMARY/ && inside  { rs = 1; summary = $0; }
-/^BEGIN:VEVENT/       { inside = 1 }

src/awk/merge.awk

@@ -1,17 +1,35 @@
-BEGIN { FS="|"; i=0; dlt = -259200; spw = 604800; }
+## src/awk/merge.awk
+## Merge a file that contains pairs of lines for start and end dates of events
+## with the approximate data file, and group the iCalendar file paths according
+## to the weeks at which the events take place.
+
+# AWK program
+BEGIN { FS="\t"; OFS="\t" }
 NR == FNR {
-  i = i + 1;
+  i = i + 1
-  from[i] = int(($1 + dlt)/ spw);
+  split($0, parts, ":")
-  getline;
+  from_year[i] = parts[1]
-  to[i] = int(($1 + dlt) / spw);
+  from_week[i] = parts[2]
+  getline
+  split($0, parts, ":")
+  to_year[i] = parts[1]
+  to_week[i] = parts[2]
   next
 } # Load start and end week numbers from first file
 
 { 
-  if (from[FNR] > to[FNR])
+  year_i = from_year[FNR]
-    print "FNR", FNR, ":", from[FNR],"-",to[FNR], "    ",$0;
+  week_i = from_week[FNR]
-  for(i=from[FNR]; i<=to[FNR]; i++) {
+  year_end = to_year[FNR]
-    week[i] = week[i] " " $5
+  week_end = to_week[FNR]
+  while(year_i <= year_end && (year_i < year_end || week_i <= week_end)) {
+    label = year_i ":" week_i ":"
+    week[label] = week[label] ? week[label] " " $5 : $5
+    week_i++
+    if (week_i > 53) {
+      week_i = 1
+      year_i++
+    }
   }
 }
-END { for (i in week) print i week[i]; }
+END { for (label in week) print label, week[label] }

src/awk/new.awk

@@ -1,95 +1,105 @@
-function escape(str)
+## src/awk/new.awk
-{
+## Generate iCalendar file from markdown description.
-  gsub("\\\\", "\\\\", str);
+##
-  gsub(";",  "\\\\;",    str);
+## @assign uid: UID to use
-  gsub(",",  "\\\\,",    str);
-}
 
-function print_fold(nameparam, content,    i, s)
+@include "lib/awk/icalendar.awk"
-{
-  i = 74 - length(nameparam);
-  s = substr(content, 1, i);
-  print nameparam s;
-  s = substr(content, i+1, 73);
-  i = i + 73;
-  while (s)
-  {
-    print " " s;
-    s = substr(content, i+1, 73);
-    i = i + 73;
-  }
-}
 
+# AWK program
 BEGIN { 
-  FS=":"; 
+  FS=":"
-  zulu = strftime("%Y%m%dT%H%M%SZ", systime(), 1);
+  zulu = strftime("%Y%m%dT%H%M%SZ", systime(), 1)
 }
-desc { desc = desc "\\n" $0; next; }
+readdesc { desc = desc ? desc "\\n" escape($0) : escape($0); next }
 {
-  from = substr($0, 1, 6) == "::: |>" ? substr($0, 8) : "";
+  from = substr($0, 1, 6) == "::: |>" ? substr($0, 8) : ""
+  if (!from)
+    exit 1
   getline
-  to = substr($0, 1, 6) == "::: <|" ? substr($0, 8) : "";
+  to = substr($0, 1, 6) == "::: <|" ? substr($0, 8) : ""
+  if (!to)
+    exit 1
   getline
-  summary = substr($0, 1, 2) == "# " ? substr($0, 3) : ""
+  location = substr($0, 1, 2) == "@ " ? escape(substr($0, 3)) : ""
+  if (location) getline
+  summary = substr($0, 1, 2) == "# " ? escape(substr($0, 3)) : ""
+  if (!summary)
+    exit 1
   getline # This line should be empty
-  getline # First line of description
+  if ($0 != "")
-  desc = $0;
+    exit 1
-  next;
+  readdesc = 1
+  next
 }
 END {
   # Sanitize input
-  # If nanoseconds are not 0, then we assume user enterd "tomorrow" or
+  # If nanoseconds are not 0, then we assume user entered "tomorrow" or
   # something the like, and we make this a date entry, as opposed to a
   # date-time entry.
-  from = from ? from : "now"
+  # Similarly, if the time is 00:00, we make this a date, as opposed to a
-  cmd = "date -d \"" from "\" +\"%N\"";
+  # date-time entry.
+  gsub("\"", "\\\"", from)
+  cmd = "date -d \"" from "\" +\"%N\""
+  cmd | getline n
+  close(cmd)
+  n = n + 0
+  cmd = "date -d \"" from "\" +\"%H%M\""
   cmd | getline t
   close(cmd)
   t = t + 0
-  if (t == 0) {
+  if (n != 0 || t == 0) {
+    from_type = "DATE"
+    cmd = "date -d \"" from "\" +\"%Y%m%d\""
+  } else {
     from_type = "DATE-TIME"
     cmd = "date -d \"" from "\" +\"@%s\" | xargs date -u +\"%Y%m%dT%H%M00Z\" -d"
-  } else {
-    from_type = "DATE"
-    cmd = "date -d \"" from "\" +\"%Y%m%d\"";
   }
-  cmd | getline from
+  suc = cmd | getline from
   close(cmd)
+  if (suc != 1) {
+    exit 1
+  }
   #
-  to = to ? to : "now"
+  gsub("\"", "\\\"", to)
-  cmd = "date -d \"" to "\" +\"%N\"";
+  cmd = "date -d \"" to "\" +\"%N\""
+  cmd | getline n
+  close(cmd)
+  n = n + 0
+  cmd = "date -d \"" to "\" +\"%H%M\""
   cmd | getline t
   close(cmd)
   t = t + 0
-  if (t == 0) {
+  if (n != 0 || t == 0) {
+    to_type = "DATE"
+    cmd = "date -d \"" to "\" +\"%Y%m%d\""
+  } else {
     to_type = "DATE-TIME"
     cmd = "date -d \"" to "\" +\"@%s\" | xargs date -u +\"%Y%m%dT%H%M00Z\" -d"
-  } else {
-    to_type = "DATE"
-    cmd = "date -d \"" to "\" +\"%Y%m%d\"";
   }
-  cmd | getline to
+  suc = cmd | getline to
   close(cmd)
-  escape(summary);
+  if (suc != 1) {
-  escape(desc);
+    exit 1
+  }
 
   # print ical
-  print "BEGIN:VCALENDAR";
+  print "BEGIN:VCALENDAR"
-  print "VERSION:2.0";
+  print "VERSION:2.0"
-  print "CALSCALE:GREGORIAN";
+  print "CALSCALE:GREGORIAN"
-  print "PRODID:-//fab//awk//EN";
+  print "PRODID:-//fab//awk//EN"
   print "BEGIN:VEVENT"
-  print "DTSTAMP:" zulu;
+  print "DTSTAMP:" zulu
-  print "UID:" uid;
+  print "UID:" uid
-  print "CLASS:PRIVATE";
+  print "CLASS:PRIVATE"
-  print "CREATED:" zulu;
+  print "CREATED:" zulu
-  print "SEQUENCE:1";
+  print "SEQUENCE:1"
-  print "LAST-MODIFIED:" zulu;
+  print "LAST-MODIFIED:" zulu
-  print "STATUS:FINAL";
+  print "STATUS:CONFIRMED"
   print "DTSTART;VALUE=" from_type ":" from
   print "DTEND;VALUE=" to_type ":" to
-  if (summary)    print_fold("SUMMARY:",     summary,       i, s);
+  if (summary)    print_fold("SUMMARY:",     summary)
-  if (desc)       print_fold("DESCRIPTION:", desc,          i, s);
+  if (desc)       print_fold("DESCRIPTION:", desc)
+  if (location)   print_fold("LOCATION:",    location)
   print "END:VEVENT"
   print "END:VCALENDAR"
 }

src/awk/parse.awk

@@ -1,46 +1,30 @@
-function parse(    dt) {
+## src/awk/parse.awk
-  # Get timezone information
+## Parse iCalendar file and print its key aspects:
-  dt = "";
+## ```
-  for (i=2; i<NF-1; i+=2) {
+## <start> <end> <fpath> <collection> <status> <summary>
-    if ($i == "TZID") {
+## ```.
-      dt = "TZ=\"" $(i+1) "\" ";
+## The output is space delimited.
-      break;
+## Summary may contain spaces, but it's the last in the list.
-    }
+##
-  }
+## @assign collection_labels: See configuration of the current program.
-  # Get date/datetime
-  return length($NF) == 8 ?
-    dt $NF :
-    dt gensub(/^([0-9]{8})T([0-9]{2})([0-9]{2})([0-9]{2})(Z)?$/, "\\1 \\2:\\3:\\4\\5", "g", $NF);
-}
 
-function parse_duration(    dt, dta, i, n, a, seps) {
+@include "lib/awk/icalendar.awk"
-  n = split($NF, a, /[PTWHMSD]/, seps);
-  delete dta;
-  for (i=2; i<=n; i++) {
-    if(seps[i] == "W") dta["weeks"]   = a[i];
-    if(seps[i] == "H") dta["hours"]   = a[i];
-    if(seps[i] == "M") dta["minutes"] = a[i];
-    if(seps[i] == "S") dta["seconds"] = a[i];
-    if(seps[i] == "D") dta["days"]    = a[i];
-  }
-  dt = a[1] ? a[1] : "+";
-  for (i in dta) {
-    dt = dt " " dta[i] " " i;
-  }
-  return dt;
-}
 
-function print_data(start, dur, end, summary,    cmd, collection) {
+# Print string of parsed data.
-  summary = substr(summary, index(summary, ":") + 1);
+#
-  gsub("\\\\n",    " ", summary); # one-liner
+# @local variables: cmd, collection, depth, path
-  gsub("\\\\N",    " ", summary); # one-liner
+# @input start: Start time of event
-  gsub("\\\\,",    ",",  summary);
+# @input dur: Boolean that indicates that `end` specifies a duration
-  gsub("\\\\;",    ";",  summary);
+# @input end: End time of event, or event duration (see `dur`)
-  gsub("\\\\\\\\", "\\", summary);
+# @input summary: Content of SUMMARY field of the event
-  depth = split(FILENAME, path, "/");
+function print_data(start, dur, end, summary,    cmd, collection, depth, path) {
+  summary = getcontent(summary)
+  gsub("\n", " ",    summary) # This will be put on a single line
+  gsub("\t", "    ", summary) # Generally, we use tab as delimiter.
+  depth = split(FILENAME, path, "/")
   fpath = path[depth-1] "/" path[depth]
-  collection = depth > 1 ? path[depth-1] : "";
+  collection = depth > 1 ? path[depth-1] : ""
-  collection = collection in collection2label ? collection2label[collection] : collection;
+  collection = collection in collection2label ? collection2label[collection] : collection
   collection = collection2label[path[depth-1]]
   end = dur ? start " " end : end
   cmd = "date -d '" start "' +\"%s\""
@@ -49,23 +33,26 @@ function print_data(start, dur, end, summary,    cmd, collection) {
   cmd = "date -d '" end "' +\"%s\""
   cmd | getline end
   close(cmd)
-  print start, end, fpath, collection, summary
+  status = status ? status : "CONFIRMED"
+  print start, end, fpath, collection, status, summary
 }
 
+# AWK program
 BEGIN { 
-  FS="[:;=]";
+  FS="[:;=]"
-  split(collection_labels, mapping, ";");
+  split(collection_labels, mapping, ";")
   for (map in mapping)
   {
-    split(mapping[map], m, "=");
+    split(mapping[map], m, "=")
-    collection2label[m[1]] = m[2];
+    collection2label[m[1]] = m[2]
   }
 }
-/^END:VEVENT/ && inside { print_data(start, dur, end, summary,    cmd, collection); exit }
+/^END:VEVENT/ && inside { print_data(start, dur, end, summary); exit }
-/^DTSTART/ && inside  { start = parse(    dt) }
+/^DTSTART/ && inside    { start = parse() }
-/^DTEND/ && inside    { end = parse(    dt) }
+/^DTEND/ && inside      { end = parse() }
-/^DURATION/ && inside { end = parse_duration(    dt, dta, i, n, a, seps); dur = 1 }
+/^DURATION/ && inside   { end = parse_duration($NF); dur = 1 }
+/^STATUS/ && inside     { status = $NF }
 /^[^ ]/ && rs           { rs = 0 }
-/^ / && rs       { summary = summary substr($0, 2); }
+/^ / && rs              { summary = summary substr($0, 2) }
-/^SUMMARY/ && inside  { rs = 1; summary = $0; }
+/^SUMMARY/ && inside    { rs = 1; summary = $0 }
 /^BEGIN:VEVENT/         { inside = 1 }

src/awk/set.awk

@@ -0,0 +1,27 @@
+## src/awk/set.awk
+## Set or replace the content of a specified field in the iCalendar file.
+##
+## @assign field: iCalendar field
+## @assign value: Content to set it to
+##
+## LIMITATION: This program does not fold long content lines.
+
+@include "lib/awk/icalendar.awk"
+
+BEGIN                 { FS = "[:;]"; zulu = strftime("%Y%m%dT%H%M%SZ", systime(), 1) }
+/^BEGIN:VEVENT$/      { inside = 1 }
+/^END:VEVENT$/        {
+  inside = 0
+  if (!duplic)
+    print field ":" escape(value)
+  seq = seq ? seq + 1 : 1
+  print "SEQUENCE:" seq
+  print "LAST-MODIFIED:" zulu
+}
+$1 == field && inside { con = 1; duplic = 1; print field ":" escape(value); next }
+$1 == field && duplic { con = 1; next }
+/^ / && con           { next }
+/^[^ ]/ && con        { con = 0 }
+/^SEQUENCE/ && inside { seq = $2; next } # store sequence number and skip
+/^LAST-MODIFIED/ && inside { next }
+{ print }

src/awk/update.awk

@@ -1,101 +1,103 @@
-function getcontent(content_line, prop)
+## src/awk/update.awk
-{
+## Update iCalendar file from markdown file.
-  return substr(content_line[prop], index(content_line[prop], ":") + 1);
-}
 
-function escape(str)
+@include "lib/awk/icalendar.awk"
-{
-  gsub("\\\\", "\\\\", str);
-  gsub(";",  "\\\\;",    str);
-  gsub(",",  "\\\\,",    str);
-}
-
-function print_fold(nameparam, content,    i, s)
-{
-  i = 74 - length(nameparam);
-  s = substr(content, 1, i);
-  print nameparam s;
-  s = substr(content, i+1, 73);
-  i = i + 73;
-  while (s)
-  {
-    print " " s;
-    s = substr(content, i+1, 73);
-    i = i + 73;
-  }
-}
 
 BEGIN { 
-  FS=":";
+  FS=":"
-  zulu = strftime("%Y%m%dT%H%M%SZ", systime(), 1);
+  zulu = strftime("%Y%m%dT%H%M%SZ", systime(), 1)
 }
 
 ENDFILE {
   if (NR == FNR)
   {
-    # If nanoseconds are not 0, then we assume user enterd "tomorrow" or
+    # If nanoseconds are not 0, then we assume user entered "tomorrow" or
     # something the like, and we make this a date entry, as opposed to a
     # date-time entry.
-    from = from ? from : "now"
+    gsub("\"", "\\\"", from)
-    cmd = "date -d \"" from "\" +\"%N\"";
+    cmd = "date -d \"" from "\" +\"%N\""
+    cmd | getline n
+    close(cmd)
+    n = n + 0
+    cmd = "date -d \"" from "\" +\"%H%M\""
     cmd | getline t
     close(cmd)
     t = t + 0
-    if (t == 0) {
+    if (n != 0 || t == 0) {
+      from_type = "DATE"
+      cmd = "date -d \"" from "\" +\"%Y%m%d\""
+    } else {
       from_type = "DATE-TIME"
       cmd = "date -d \"" from "\" +\"@%s\" | xargs date -u +\"%Y%m%dT%H%M00Z\" -d"
-    } else {
-      from_type = "DATE"
-      cmd = "date -d \"" from "\" +\"%Y%m%d\"";
     }
-    cmd | getline from
+    suc = cmd | getline from
     close(cmd)
+    if (suc != 1) {
+      exit 1
+    }
     #
-    to = to ? to : "now"
+    gsub("\"", "\\\"", to)
-    cmd = "date -d \"" to "\" +\"%N\"";
+    cmd = "date -d \"" to "\" +\"%N\""
+    cmd | getline n
+    close(cmd)
+    n = n + 0
+    cmd = "date -d \"" to "\" +\"%H%M\""
     cmd | getline t
     close(cmd)
     t = t + 0
-    if (t == 0) {
+    if (n != 0 || t == 0) {
+      to_type = "DATE"
+      cmd = "date -d \"" to "\" +\"%Y%m%d\""
+    } else {
       to_type = "DATE-TIME"
       cmd = "date -d \"" to "\" +\"@%s\" | xargs date -u +\"%Y%m%dT%H%M00Z\" -d"
-    } else {
-      to_type = "DATE"
-      cmd = "date -d \"" to "\" +\"%Y%m%d\"";
     }
-    cmd | getline to
+    suc = cmd | getline to
     close(cmd)
+    if (suc != 1) {
+      exit 1
+    }
   }
-  escape(summary);
-  escape(desc);
 }
 
-NR == FNR && desc { desc = desc "\\n" $0; next; }
+NR == FNR && readdesc { desc = desc ? desc "\\n" escape($0) : escape($0); next }
 NR == FNR {
-  from = substr($0, 1, 6) == "::: |>" ? substr($0, 8) : "";
+  from = substr($0, 1, 6) == "::: |>" ? substr($0, 8) : ""
+  if (!from)
+    exit 1
   getline
-  to = substr($0, 1, 6) == "::: <|" ? substr($0, 8) : "";
+  to = substr($0, 1, 6) == "::: <|" ? substr($0, 8) : ""
+  if (!to)
+    exit 1
   getline
-  summary = substr($0, 1, 2) == "# " ? substr($0, 3) : ""
+  location = substr($0, 1, 2) == "@ " ? escape(substr($0, 3)) : ""
+  if (location) getline
+  summary = substr($0, 1, 2) == "# " ? escape(substr($0, 3)) : ""
+  if (!summary)
+    exit 1
   getline # This line should be empty
-  getline # First line of description
+  if ($0 != "")
-  desc = $0;
+    exit 1
-  next;
+  readdesc = 1
+  next
 }
 
-/^BEGIN:VEVENT$/                                              { inside = 1; print; next }
-/^X-ALT-DESC/ && inside                                       { next } # drop this alternative description
-/^ / && inside                                                { next } # drop this folded line (the only content with folded lines will be updated)
-/^(DTSTART|DTEND|SUMMARY|CATEGORIES|DESCRIPTION|LAST-MODIFIED)/ && inside { next } # skip for now, we will write updated fields at the end
-/^SEQUENCE/ && inside                                         { seq = $2; next } # store sequence number and skip
 /^END:VEVENT$/ {
   seq = seq ? seq + 1 : 1
   print "SEQUENCE:" seq
   print "LAST-MODIFIED:" zulu
   print "DTSTART;VALUE=" from_type ":" from
   print "DTEND;VALUE=" to_type ":" to
-  print_fold("SUMMARY:",     summary,       i, s)
+  print_fold("SUMMARY:",     summary)
-  print_fold("DESCRIPTION:", desc,          i, s)
+  print_fold("DESCRIPTION:", desc)
+  print_fold("LOCATION:",    location)
   inside = ""
+  skipf = 0
 }
+/^BEGIN:VEVENT$/           { inside = 1 }
+/^ / && skipf              { next } # drop this folded line
+/^[^ ]/ && skipf           { skipf = 0 }
+/^(DTSTART|DTEND|SUMMARY|LOCATION|CATEGORIES|DESCRIPTION|LAST-MODIFIED)/ && inside { skipf = 1; next } # skip for now, we will write updated fields at the end
+/^X-ALT-DESC/ && inside    { skipf = 1; next } # skip
+/^SEQUENCE/ && inside      { seq = $2; next } # store sequence number and skip
 { print }

src/awk/weeks.awk

@@ -1,44 +0,0 @@
-function parse(    dt) {
-  # Get timezone information
-  dt = "";
-  for (i=2; i<NF-1; i+=2) {
-    if ($i == "TZID") {
-      dt = "TZ=\"" $(i+1) "\" ";
-      break;
-    }
-  }
-  # Get date/datetime
-  return length($NF) == 8 ?
-    dt $NF :
-    dt gensub(/^([0-9]{8})T([0-9]{2})([0-9]{2})([0-9]{2})(Z)?$/, "\\1 \\2:\\3:\\4\\5", "g", $NF);
-}
-
-function parse_duration(    dt, dta, i, n, a, seps) {
-  n = split($NF, a, /[PTWHMSD]/, seps);
-  delete dta;
-  for (i=2; i<=n; i++) {
-    if(seps[i] == "W") dta["weeks"]   = a[i];
-    if(seps[i] == "H") dta["hours"]   = a[i];
-    if(seps[i] == "M") dta["minutes"] = a[i];
-    if(seps[i] == "S") dta["seconds"] = a[i];
-    if(seps[i] == "D") dta["days"]    = a[i];
-  }
-  dt = a[1] ? a[1] : "+";
-  for (i in dta) {
-    dt = dt " " dta[i] " " i;
-  }
-  return dt;
-}
-
-function fn(path,    n, a) {
-  n = split(path, a, "/");
-  return a[n-1] "/" a[n];
-}
-
-BEGIN                 { FS="[:;=]"; OFS="|" }
-BEGINFILE             { inside = 0; dur = 0; start = "ERROR"; end = "ERROR" }
-/^END:VEVENT/         { print start, dur ? start " " end : end, fn(FILENAME,    n, a); nextfile }
-/^DTSTART/ && inside  { start = parse(    dt) }
-/^DTEND/ && inside    { end = parse(    dt) }
-/^DURATION/ && inside { end = parse_duration(    dt, dta, i, n, a, seps); dur = 1 }
-/^BEGIN:VEVENT/       { inside = 1 }

src/awk/weekview.awk

@@ -1,23 +1,38 @@
-function c() {
+## src/awk/weekview.awk
-  return CYAN substr($0, index($0, ">") + 1) OFF "  " RED "/" OFF
+## Print view of all appointments of the current week.
+## Generates view from
+##   printf "%s\t%s\t%s\t%s\n" "$i" "$s" "$e" "$description"
+##
+## @assign startofweek: Date of first day in the week
+
+# Functions
+
+# Compose line that will display a day in the week.
+# 
+# @input desc: String with a description of the event
+# @return: Single-line string
+function c(desc) {
+  return CYAN desc OFF "  " RED "/" OFF
 }
+
+# AWK program
+
 BEGIN {
-  GREEN = "\033[1;32m";
+  FS = "\t"
-  RED = "\033[1;31m";
+  OFS = "\t"
-  WHITE = "\033[1;97m";
+  GREEN = "\033[1;32m"
-  CYAN = "\033[1;36m";
+  RED = "\033[1;31m"
-  FAINT = "\033[2m";
+  CYAN = "\033[1;36m"
-  OFF = "\033[m";
+  OFF = "\033[m"
-  OFS = "|"
 }
-/^[0-7] 00:00 -- 00:00/ { dayline = dayline " " c(); next }
+$2 == "00:00" && $3 == "00:00" { dayline = dayline " " c($4); next }
-/^[0-7] 00:00 -- / { dayline = dayline " <--" $4 " " c(); next }
+$2 == "00:00"                  { dayline = dayline " → " $3 " " c($4); next }
-/^[0-7] [0-9]{2}:[0-9]{2} -- 00:00/ { dayline = dayline " " $2 "--> " c(); next }
+$3 == "00:00"                  { dayline = dayline " " $2 " → " c($4); next }
-/^[0-7] [0-9]{2}:[0-9]{2} -- [0-9]{2}:[0-9]{2}/ { dayline = dayline " " $2 " - " $4 " " c(); next }
+NF == 4                        { dayline = dayline " " $2 " – " $3 " " c($4); next }
-/^[0-7]$/ && dayline { print "+", startofweek " +" $0-1 " days", "", dayline; }
+NF == 1 && dayline             { print "+", startofweek " +" $1-1 " days", "", dayline }
-/^[0-7]$/ {
+NF == 1 {
-  cmd = "date -d '" startofweek " +" $0 " days' +\"%a %e %b %Y\"";
+  cmd = "date -d '" startofweek " +" $1 " days' +\"%a %e %b %Y\""
-  cmd | getline dayline;
+  cmd | getline dayline
-  close(cmd);
+  close(cmd)
   dayline = GREEN dayline ":   " OFF
 }

src/lib/awk/icalendar.awk

@@ -0,0 +1,104 @@
+# Escape string to be used as content in iCalendar files.
+#
+# @input str: String to escape
+# @return: Escaped string
+function escape(str)
+{
+  gsub("\\\\", "\\\\", str)
+  gsub(";",    "\\;",  str)
+  gsub(",",    "\\,",  str)
+  return str
+}
+
+# Print property with its content and fold according to the iCalendar
+# specification.
+#
+# @local variables: i, s
+# @input nameparam: Property name with optional parameters
+# @input content: Escaped content
+function print_fold(nameparam, content,    i, s)
+{
+  i = 74 - length(nameparam)
+  s = substr(content, 1, i)
+  print nameparam s
+  s = substr(content, i+1, 73)
+  i = i + 73
+  while (s)
+  {
+    print " " s
+    s = substr(content, i+1, 73)
+    i = i + 73
+  }
+}
+
+# Unescape string
+#
+# @local variables: i, c, c2, res
+# @input str: String
+# @return: Unescaped string
+function unescape(str,    i, c, c2, res) {
+  for(i=1; i<=length(str);i++) {
+    c = substr(str, i, 1)
+    if (c != "\\") {
+      res = res c
+      continue
+    }
+    i++
+    c2 = substr(str, i, 1)
+    if (c2 == "n" || c2 == "N") {
+      res = res "\n"
+      continue
+    }
+    # Alternatively, c2 is "\\" or "," or ";". In each case, append res with
+    # c2. If the strings has been escaped correctly, then the character c2
+    # cannot be anything else. To be fail-safe, simply append res with c2.
+    res = res c2
+  }
+  return res
+}
+
+# Isolate content part of an iCalendar line, and unescape.
+#
+# @input str: String
+# @return: Unescaped content part
+function getcontent(str) {
+  return unescape(substr(str, index(str, ":") + 1))
+}
+
+# Time-zone aware parsing of the date/date-time entry at the current record.
+#
+# @local variables: dt
+# @return: date or date-time string that can be used in date (1)
+function parse(    dt) {
+  # Get timezone information
+  for (i=2; i<NF-1; i+=2) {
+    if ($i == "TZID") {
+      dt = "TZ=\"" $(i+1) "\" "
+      break
+    }
+  }
+  # Get date/date-time
+  return length($NF) == 8 ?
+    dt $NF :
+    dt gensub(/^([0-9]{8})T([0-9]{2})([0-9]{2})([0-9]{2})(Z)?$/, "\\1 \\2:\\3:\\4\\5", "g", $NF)
+}
+
+# Map iCalendar duration specification into the format to be used in date (1).
+#
+# @local variables: dt, dta, i, n, a, seps
+# @input duration: iCalendar duration string
+# @return: relative-date/date-time specification to be used in date (1)
+function parse_duration(duration,    dt, dta, i, n, a, seps) {
+  n = split(duration, a, /[PTWHMSD]/, seps)
+  for (i=2; i<=n; i++) {
+    if(seps[i] == "W") dta["weeks"]   = a[i]
+    if(seps[i] == "H") dta["hours"]   = a[i]
+    if(seps[i] == "M") dta["minutes"] = a[i]
+    if(seps[i] == "S") dta["seconds"] = a[i]
+    if(seps[i] == "D") dta["days"]    = a[i]
+  }
+  dt = a[1] ? a[1] : "+"
+  for (i in dta)
+    dt = dt " " dta[i] " " i
+  return dt
+}

src/sh/awkscripts.sh

@@ -0,0 +1,106 @@
+# AWK scripts
+# - AWK_APPROX:   Generate approximate data of all files
+# - AWK_CALSHIFT: Shift calendar to start weeks on Mondays
+# - AWK_CALANNOT: Annotate calendar
+# - AWK_DAYVIEW:  Generate view of the day
+# - AWK_GET:      Print field of iCalendar file
+# - AWK_MERGE:    Generate list of weeks with associated iCalendar files
+# - AWK_NEW:      Make new iCalendar file
+# - AWK_PARSE:    Timezone aware parsing of iCalendar file for day view
+# - AWK_SET:      Set value of specific field in iCalendar file
+# - AWK_UPDATE:   Update iCalendar file
+# - AWK_WEEKVIEW: Generate view of the week
+# - AWK_ATTACHLS: List attachments
+# - AWK_ATTACHDD: Store attachment
+# - AWK_ATTACHRM: Remove attachment
+# - AWK_ATTACH:   Add attachment
+
+AWK_APPROX=$(
+  cat <<'EOF'
+@@include awk/approx.awk
+EOF
+)
+
+AWK_MERGE=$(
+  cat <<'EOF'
+@@include awk/merge.awk
+EOF
+)
+
+AWK_PARSE=$(
+  cat <<'EOF'
+@@include awk/parse.awk
+EOF
+)
+
+AWK_WEEKVIEW=$(
+  cat <<'EOF'
+@@include awk/weekview.awk
+EOF
+)
+
+AWK_DAYVIEW=$(
+  cat <<'EOF'
+@@include awk/dayview.awk
+EOF
+)
+
+AWK_GET=$(
+  cat <<'EOF'
+@@include awk/get.awk
+EOF
+)
+
+AWK_UPDATE=$(
+  cat <<'EOF'
+@@include awk/update.awk
+EOF
+)
+
+AWK_NEW=$(
+  cat <<'EOF'
+@@include awk/new.awk
+EOF
+)
+
+AWK_CALSHIFT=$(
+  cat <<'EOF'
+@@include awk/calshift.awk
+EOF
+)
+
+AWK_CALANNOT=$(
+  cat <<'EOF'
+@@include awk/calannot.awk
+EOF
+)
+
+AWK_SET=$(
+  cat <<'EOF'
+@@include awk/set.awk
+EOF
+)
+
+AWK_ATTACHLS=$(
+  cat <<'EOF'
+@@include awk/attachls.awk
+EOF
+)
+
+AWK_ATTACHDD=$(
+  cat <<'EOF'
+@@include awk/attachdd.awk
+EOF
+)
+
+AWK_ATTACHRM=$(
+  cat <<'EOF'
+@@include awk/attachrm.awk
+EOF
+)
+
+AWK_ATTACH=$(
+  cat <<'EOF'
+@@include awk/attach.awk
+EOF
+)

src/sh/cliextra.sh

@@ -0,0 +1,129 @@
+# Extra command-line options
+# - --import-ni
+# - --import
+# - --git
+# - --git-init
+
+# Import iCalendar file noninteractively
+#
+# @input $2: Absolute path to iCalendar file
+# @input $3: Collection
+# @return: On success, returns 0, otherwise 1
+if [ "${1:-}" = "--import-ni" ]; then
+  shift
+  file="${1:-}"
+  collection="${2:-}"
+  if [ ! -f "$file" ]; then
+    err "File \"$file\" does not exist"
+    exit 1
+  fi
+  for c in $(echo "$COLLECTION_LABELS" | sed "s|=[^;]*;| |g"); do
+    if [ "$collection" = "$c" ]; then
+      cexists="yes"
+      break
+    fi
+  done
+  if [ -n "${cexists:-}" ] && [ -d "$ROOT/$collection" ]; then
+    __import_to_collection "$file" "$collection"
+  else
+    err "Collection \"$collection\" does not exist"
+    exit 1
+  fi
+  exit
+fi
+
+# Import iCalendar file.
+#
+# @input $2: Absolute path to iCalendar file
+# @return: On success, returns 0, otherwise 1
+if [ "${1:-}" = "--import" ]; then
+  shift
+  file="${1:-}"
+  if [ ! -f "$file" ]; then
+    err "File \"$file\" does not exist"
+    return 1
+  fi
+  line=$(awk \
+    -v collection_labels="$COLLECTION_LABELS" \
+    "$AWK_PARSE" "$file")
+  set -- $line
+  startsec="${1:-}"
+  endsec="${2:-}"
+  if [ -z "$line" ] || [ -z "$startsec" ] || [ -z "$endsec" ]; then
+    err "File \"$file\" does not look like an iCalendar file containing an event"
+    return 1
+  fi
+  start=$(__datetime_human_machine "$startsec")
+  end=$(__datetime_human_machine "$endsec")
+  location=$(awk -v field="LOCATION" "$AWK_GET" "$file")
+  summary=$(awk -v field="SUMMARY" "$AWK_GET" "$file")
+  description=$(awk -v field="DESCRIPTION" "$AWK_GET" "$file")
+  filetmp=$(mktemp --suffix='.md')
+  (
+    echo "::: |> $start"
+    echo "::: <| $end"
+  ) >"$filetmp"
+  if [ -n "$location" ]; then
+    echo "@ $location" >>"$filetmp"
+  fi
+  (
+    echo "# $summary"
+    echo ""
+    echo "$description"
+  ) >>"$filetmp"
+  $CAT "$filetmp" >/dev/tty
+  while true; do
+    printf "Do you want to import this entry? (yes/no): " >/dev/tty
+    read -r yn
+    case $yn in
+    "yes")
+      collection=$(echo "$COLLECTION_LABELS" | tr ';' '\n' | awk '/./ {print}' | $FZF --margin="30%" --no-info --delimiter='=' --with-nth=2 --accept-nth=1)
+      if [ -z "$collection" ]; then
+        exit
+      fi
+      __import_to_collection "$file" "$collection"
+      break
+      ;;
+    "no")
+      break
+      ;;
+    *)
+      echo "Please answer \"yes\" or \"no\"." >/dev/tty
+      ;;
+    esac
+  done
+  rm -f "$filetmp"
+  exit
+fi
+
+# Run git command
+#
+# @input $2..: Git command
+# @return: On success, returns 0, otherwise 1
+if [ "${1:-}" = "--git" ]; then
+  if [ -z "${GIT:-}" ]; then
+    err "Git not supported, run \`$0 --git-init\` first"
+    return 1
+  fi
+  shift
+  $GIT "$@"
+  exit
+fi
+
+# Enable the ues of git
+#
+# @return: On success, returns 0, otherwise 1
+if [ "${1:-}" = "--git-init" ]; then
+  if [ -n "${GIT:-}" ]; then
+    err "Git already enabled"
+    return 1
+  fi
+  if ! command -v "git" >/dev/null; then
+    err "Git command not found"
+    return 1
+  fi
+  git -C "$ROOT" init
+  git -C "$ROOT" add -A
+  git -C "$ROOT" commit -m 'Initial commit: Start git tracking'
+  exit
+fi

src/sh/clipreview.sh

@@ -0,0 +1,100 @@
+# Preview command-line options
+# - --preview-event
+# - --preview_week
+
+# Print preview of event and exit.
+#
+# @input $2: Line from day view containing an event
+if [ "${1:-}" = "--preview-event" ]; then
+  hour=$(echo "$2" | cut -f 2)
+  start=$(echo "$2" | cut -f 3)
+  end=$(echo "$2" | cut -f 4)
+  fpath=$(echo "$2" | cut -f 5)
+  if [ -n "$hour" ] && [ -n "$fpath" ]; then
+    fpath="$ROOT/$fpath"
+    start=$(datetime_str "$start" "%a ")
+    end=$(datetime_str "$end" "%a ")
+    location=$(awk -v field="LOCATION" "$AWK_GET" "$fpath")
+    status=$(awk -v field="STATUS" "$AWK_GET" "$fpath")
+    if [ "$status" = "TENTATIVE" ]; then
+      symb="🟡"
+    elif [ "$status" = "CANCELLED" ]; then
+      symb="❌"
+    fi
+    echo "📅${symb:-} ${CYAN}$start${OFF} → ${CYAN}$end${OFF}"
+    if [ -n "${location:-}" ]; then
+      echo "📍 ${CYAN}$location${OFF}"
+    fi
+    attcnt=$(awk "$AWK_ATTACHLS" "$fpath" | wc -l)
+    if [ "$attcnt" -gt 0 ]; then
+      echo "🔗 $attcnt attachments"
+    fi
+    echo ""
+    awk -v field="DESCRIPTION" "$AWK_GET" "$fpath" | $CAT
+  fi
+  exit
+fi
+
+# Print preview of week.
+#
+# @input $2: Line from week view
+if [ "${1:-}" = "--preview-week" ]; then
+  sign=$(echo "$2" | cut -f 1)
+  if [ "$sign" = "+" ]; then
+    startdate=$(echo "$2" | cut -f 2)
+    set -- $(date -d "$startdate" +"%Y %m %d")
+    year=$1
+    month=$2
+    day=$3
+    set -- $(date -d "today" +"%Y %m %d")
+    year_cur=$1
+    month_cur=$2
+    day_cur=$3
+    # Previous months
+    set -- $(month_previous "$month" "$year")
+    month_pre="$1"
+    year_pre="$2"
+    set -- $(month_previous "$month_pre" "$year_pre")
+    month_pre2="$1"
+    year_pre2="$2"
+    # Next months
+    set -- $(month_next "$month" "$year")
+    month_nex="$1"
+    year_nex="$2"
+    set -- $(month_next "$month_nex" "$year_nex")
+    month_nex2="$1"
+    year_nex2="$2"
+    set -- $(month_next "$month_nex2" "$year_nex2")
+    month_nex3="$1"
+    year_nex3="$2"
+    # Highlight today
+    if [ "$month_pre2" -eq "$month_cur" ] && [ "$year_pre2" -eq "$year_cur" ]; then
+      var_pre2=$day_cur
+    fi
+    if [ "$month_pre" -eq "$month_cur" ] && [ "$year_pre" -eq "$year_cur" ]; then
+      var_pre=$day_cur
+    fi
+    if [ "$month" -eq "$month_cur" ] && [ "$year" -eq "$year_cur" ]; then
+      var=$day_cur
+    fi
+    if [ "$month_nex" -eq "$month_cur" ] && [ "$year_nex" -eq "$year_cur" ]; then
+      var_nex=$day_cur
+    fi
+    if [ "$month_nex2" -eq "$month_cur" ] && [ "$year_nex2" -eq "$year_cur" ]; then
+      var_nex2=$day_cur
+    fi
+    if [ "$month_nex3" -eq "$month_cur" ] && [ "$year_nex3" -eq "$year_cur" ]; then
+      var_nex3=$day_cur
+    fi
+    # show
+    (
+      cal "$month_pre2" "$year_pre2" | awk "$AWK_CALSHIFT" | awk -v cur="${var_pre2:-}" "$AWK_CALANNOT"
+      cal "$month_pre" "$year_pre" | awk "$AWK_CALSHIFT" | awk -v cur="${var_pre:-}" "$AWK_CALANNOT"
+      cal "$month" "$year" | awk "$AWK_CALSHIFT" | awk -v cur="${var:-}" -v day="$day" "$AWK_CALANNOT"
+      cal "$month_nex" "$year_nex" | awk "$AWK_CALSHIFT" | awk -v cur="${var_nex:-}" "$AWK_CALANNOT"
+      cal "$month_nex2" "$year_nex2" | awk "$AWK_CALSHIFT" | awk -v cur="${var_nex2:-}" "$AWK_CALANNOT"
+      cal "$month_nex3" "$year_nex3" | awk "$AWK_CALSHIFT" | awk -v cur="${var_nex3:-}" "$AWK_CALANNOT"
+    ) | awk '{ l[NR%8] = l[NR%8] "    " $0 } END {for (i in l) if (i>0) print l[i] }'
+  fi
+  exit
+fi

src/sh/clireload.sh

@@ -0,0 +1,31 @@
+# Command-line Arguments for reloading views
+# - --reload-day
+# - --reload-week
+# - --reload-all
+
+# Reload view of specified day.
+#
+# @input $2.. (optional): Specification of day, defaults to `today`
+if [ "${1:-}" = "--reload-day" ]; then
+  shift
+  DISPLAY_DATE=${*:-today}
+  __view_day
+  exit
+fi
+
+# Reload view of the week containing the specified date.
+#
+# @input $2.. (optional): Specification of day, defaults to `today`
+if [ "${1:-}" = "--reload-week" ]; then
+  shift
+  DISPLAY_DATE=${*:-today}
+  DISPLAY_POS=$((8 - $(date -d "$DISPLAY_DATE" +"%u")))
+  __view_week
+  exit
+fi
+
+# Reload view of all entries.
+if [ "${1:-}" = "--reload-all" ]; then
+  __view_all
+  exit
+fi

src/sh/config.sh

@@ -0,0 +1,65 @@
+# Load Configuration
+# - ROOT:                 Directory containing the collections
+# - COLLECTION_LABELS:    Mappings between collections and labels
+# - SYNC_CMD (optional):  Synchronization command
+# - DAY_START (optional): Hour of start of the day (defaults to 8)
+# - DAY_END (optional):   Hour of end of the day (defaults to 18)
+# - EDITOR (optional):    Your favorite editor, is usually already exported
+# - TZ (optional):        Your favorite timezone, usually system's choice
+# - LC_TIME (optional):   Your favorite locale for date and time
+# - ZI_DIR (optional):    Location of tzdata, defaults to /usr/share/zoneinfo
+
+CONFIGFILE="$HOME/.config/fzf-vcal/config"
+if [ ! -f "$CONFIGFILE" ]; then
+  err "Configuration '$CONFIGFILE' not found."
+  exit 1
+fi
+# shellcheck source=/dev/null
+. "$CONFIGFILE"
+if [ -z "${ROOT:-}" ] || [ -z "${COLLECTION_LABELS:-}" ]; then
+  err "Configuration is incomplete."
+  exit 1
+fi
+SYNC_CMD=${SYNC_CMD:-echo 'Synchronization disabled'}
+DAY_START=${DAY_START:-8}
+DAY_END=${DAY_END:-18}
+ZI_DIR=${ZI_DIR:-/usr/share/zoneinfo/posix}
+if [ ! -d "$ZI_DIR" ]; then
+  err "Could not determine time-zone information"
+  exit 1
+fi
+OPEN=${OPEN:-open}
+
+# Check and load required tools
+# - FZF:     Fuzzy finder `fzf``
+# - UUIDGEN: Tool `uuidgen` to generate random uids
+# - CAT:     `bat` or `batcat` or `cat`
+# - GIT:     `git` if it exists
+#
+# The presence of POSIX tools is not checked.
+
+if command -v "fzf" >/dev/null; then
+  FZF="fzf --black"
+else
+  err "Did not find the command-line fuzzy finder fzf."
+  exit 1
+fi
+
+if command -v "uuidgen" >/dev/null; then
+  UUIDGEN="uuidgen"
+else
+  err "Did not find the uuidgen command."
+  exit 1
+fi
+
+if command -v "bat" >/dev/null; then
+  CAT="bat"
+elif command -v "batcat" >/dev/null; then
+  CAT="batcat"
+fi
+CAT=${CAT:+$CAT --color=always --style=numbers --language=md}
+CAT=${CAT:-cat}
+
+if command -v "git" >/dev/null && [ -d "$ROOT/.git" ]; then
+  GIT="git -C $ROOT"
+fi

src/sh/icalendar.sh

@@ -0,0 +1,256 @@
+# iCalendar modification wrapper
+# - __edit
+# - __new
+# - __delete
+# - __import_to_collection
+# - __cancel_toggle
+# - __tentative_toggle
+# - __add_attachment
+
+# Edit iCalendar file.
+#
+# @input $1: Start date/date-time
+# @input $2: End date/date-time
+# @input $3: Path to iCalendar file (relative to `$ROOT`)
+# @req $AWK_GET:    Awk script to extract fields from iCalendar file
+# @req $AWK_UPDATE: Awk script to update iCalendar file
+# @req $EDITOR:     Environment variable of your favorite editor
+__edit() {
+  start=$(__datetime_human_machine "$1")
+  end=$(__datetime_human_machine "$2")
+  fpath="$ROOT/$3"
+  location=$(awk -v field="LOCATION" "$AWK_GET" "$fpath")
+  summary=$(awk -v field="SUMMARY" "$AWK_GET" "$fpath")
+  description=$(awk -v field="DESCRIPTION" "$AWK_GET" "$fpath")
+  filetmp=$(mktemp --suffix='.md')
+  printf "::: |> %s\n::: <| %s\n" "$start" "$end" >"$filetmp"
+  if [ -n "$location" ]; then
+    printf "@ %s\n" "$location" >>"$filetmp"
+  fi
+  printf "# %s\n\n%s\n" "$summary" "$description" >>"$filetmp"
+  checksum=$(cksum "$filetmp")
+  $EDITOR "$filetmp" >/dev/tty
+
+  # Update only if changes are detected
+  if [ "$checksum" != "$(cksum "$filetmp")" ]; then
+    filenew="$filetmp.ics"
+    if awk "$AWK_UPDATE" "$filetmp" "$fpath" >"$filenew"; then
+      mv "$filenew" "$fpath"
+      if [ -n "${GIT:-}" ]; then
+        $GIT add "$fpath"
+        $GIT commit -q -m "Modified event '$(__summary_for_commit "$fpath") ...'" -- "$fpath"
+      fi
+      __refresh_data
+    else
+      rm -f "$filenew"
+      err "Failed to edit entry. Press <enter> to continue."
+      read -r tmp
+    fi
+  fi
+  rm "$filetmp"
+}
+
+# Generate new iCalendar file
+#
+# This function also sets the `$start` variable to the start of the new entry.
+# On failure, start will be empty.
+#
+# If some start has been specified and the nanoseconds are not 0, we assume
+# that the user entered "tomorrow" or something like that, and did not
+# specify the time. So, we will use the `$DAY_START` time of that date.
+# If the user specified a malformed date/date-time, we fail.
+#
+# @input $1 (optional): Date or datetime, defaults to today.
+# @req $COLLECTION_LABELS: Mapping between collections and lables (see configuration)
+# @req $UUIDGEN:           `uuidgen` command
+# @req $ROOT:              Path that contains the collections (see configuration)
+# @req $EDITOR:            Environment variable of your favorite editor
+# @req $AWK_GET:           Awk script to extract fields from iCalendar file
+# @req $AWK_new:           Awk script to generate iCalendar file
+__new() {
+  collection=$(echo "$COLLECTION_LABELS" | tr ';' '\n' | awk '/./ {print}' | $FZF --margin="30%" --no-info --delimiter='=' --with-nth=2 --accept-nth=1)
+  fpath=""
+  while [ -f "$fpath" ] || [ -z "$fpath" ]; do
+    uuid=$($UUIDGEN)
+    fpath="$ROOT/$collection/$uuid.ics"
+  done
+  d="today $DAY_START"
+  if [ -n "${1:-}" ]; then
+    d="$1"
+    if [ "$(date -d "$1" +"%N")" -ne 0 ]; then
+      d="$d $DAY_START:00"
+    fi
+  fi
+  startsec=$(date -d "$d" +"%s")
+  endsec=$((startsec + 3600))
+  start=$(__datetime_human_machine "$startsec")
+  end=$(__datetime_human_machine "$endsec")
+  filetmp=$(mktemp --suffix='.md')
+  (
+    echo "::: |> $start"
+    echo "::: <| $end"
+    echo "@ <!-- write location here, optional line -->"
+    echo "# <!-- write summary here -->"
+    echo ""
+  ) >"$filetmp"
+  checksum=$(cksum "$filetmp")
+  $EDITOR "$filetmp" >/dev/tty
+
+  # Update only if changes are detected
+  if [ "$checksum" != "$(cksum "$filetmp")" ]; then
+    filenew="$filetmp.ics"
+    if awk -v uid="$uuid" "$AWK_NEW" "$filetmp" >"$filenew"; then
+      mv "$filenew" "$fpath"
+      if [ -n "${GIT:-}" ]; then
+        $GIT add "$fpath"
+        $GIT commit -q -m "Added event '$(__summary_for_commit "$fpath") ...'" -- "$fpath"
+      fi
+      start=$(awk -v field="DTSTART" "$AWK_GET" "$fpath" | grep -o '[0-9]\{8\}')
+    else
+      rm -f "$filenew"
+      start=""
+      err "Failed to create new entry. Press <enter> to continue."
+      read -r tmp
+    fi
+  fi
+  rm "$filetmp"
+}
+
+# Delete iCalendar file
+#
+# @input $1: Path to iCalendar file, relative to `$ROOT`
+# @req $ROOT: Path that contains the collections (see configuration)
+# @req $AWK_GET: Awk script to extract fields from iCalendar file
+__delete() {
+  fpath="$ROOT/$1"
+  summary=$(awk -v field="SUMMARY" "$AWK_GET" "$fpath")
+  while true; do
+    printf "Do you want to delete the entry with the title \"%s\"? (yes/no): " "$summary" >/dev/tty
+    read -r yn
+    case $yn in
+    "yes")
+      sfg="$(__summary_for_commit "$fpath")"
+      rm -v "$fpath"
+      if [ -n "${GIT:-}" ]; then
+        $GIT add "$fpath"
+        $GIT commit -q -m "Deleted event '$sfg ...'" -- "$fpath"
+      fi
+      break
+      ;;
+    "no")
+      break
+      ;;
+    *)
+      echo "Please answer \"yes\" or \"no\"." >/dev/tty
+      ;;
+    esac
+  done
+}
+
+# Import iCalendar file to specified collection. The only modification made to
+# the file is setting the UID.
+#
+# @input $1: path to iCalendar file
+# @input $2: collection name
+# @req $ROOT: Path that contains the collections (see configuration)
+# @req $UUIDGEN: `uuidgen` command
+# @req $AWK_SET: Awk script to set field value
+__import_to_collection() {
+  file="$1"
+  collection="$2"
+  fpath=""
+  while [ -f "$fpath" ] || [ -z "$fpath" ]; do
+    uuid=$($UUIDGEN)
+    fpath="$ROOT/$collection/$uuid.ics"
+  done
+  filetmp=$(mktemp)
+  awk -v field="UID" -v value="$uuid" "$AWK_SET" "$file" >"$filetmp"
+  mv "$filetmp" "$fpath"
+  if [ -n "${GIT:-}" ]; then
+    $GIT add "$fpath"
+    $GIT commit -q -m "Imported event '$(__summary_for_commit "$fpath") ...'" -- "$fpath"
+  fi
+}
+
+# Set status of appointment to CANCELLED or CONFIRMED (toggle)
+#
+# @input $1: path to iCalendar file
+# @req $ROOT: Path that contains the collections (see configuration)
+# @req $AWK_SET: Awk script to set field value
+# @req $AWK_GET: Awk script to extract fields from iCalendar file
+__cancel_toggle() {
+  fpath="$ROOT/$1"
+  status=$(awk -v field="STATUS" "$AWK_GET" "$fpath")
+  newstatus="CANCELLED"
+  if [ "${status:-}" = "$newstatus" ]; then
+    newstatus="CONFIRMED"
+  fi
+  filetmp=$(mktemp)
+  awk -v field="STATUS" -v value="$newstatus" "$AWK_SET" "$fpath" >"$filetmp"
+  mv "$filetmp" "$fpath"
+  if [ -n "${GIT:-}" ]; then
+    $GIT add "$fpath"
+    $GIT commit -q -m "Event '$(__summary_for_commit "$fpath") ...' has now status $status" -- "$fpath"
+  fi
+}
+
+# Toggle status flag: CONFIRMED <-> TENTATIVE
+#
+# @input $1: path to iCalendar file
+# @req $ROOT: Path that contains the collections (see configuration)
+# @req $AWK_SET: Awk script to set field value
+# @req $AWK_GET: Awk script to extract fields from iCalendar file
+__tentative_toggle() {
+  fpath="$ROOT/$1"
+  status=$(awk -v field="STATUS" "$AWK_GET" "$fpath")
+  newstatus="TENTATIVE"
+  if [ "${status:-}" = "$newstatus" ]; then
+    newstatus="CONFIRMED"
+  fi
+  filetmp=$(mktemp)
+  awk -v field="STATUS" -v value="$newstatus" "$AWK_SET" "$fpath" >"$filetmp"
+  mv "$filetmp" "$fpath"
+  if [ -n "${GIT:-}" ]; then
+    $GIT add "$fpath"
+    $GIT commit -q -m "Event '$(__summary_for_commit "$fpath") ...' has now status $status" -- "$fpath"
+  fi
+}
+
+# Prepend attachment to iCalendar file
+#
+# @input $1: path to iCalendar file
+# @req $ROOT: Path that contains the collections (see configuration)
+# @req $FZF: Fuzzy finder
+# @req $AWK_ATTACH: Awk script to add attachment
+__add_attachment() {
+  fpath="$ROOT/$1"
+  sel=$(
+    $FZF --prompt="Select attachment> " \
+      --walker="file,hidden" \
+      --walker-root="$HOME" \
+      --expect="ctrl-c,ctrl-g,ctrl-q,esc"
+  )
+  key=$(echo "$sel" | head -1)
+  f=$(echo "$sel" | tail -1)
+  if [ -n "$key" ]; then
+    f=""
+  fi
+  if [ -z "$f" ] || [ ! -f "$f" ]; then
+    return
+  fi
+  filename=$(basename "$f")
+  mime=$(file -b -i "$f" | cut -d ';' -f 1)
+  if [ -z "$mime" ]; then
+    mime="application/octet-stream"
+  fi
+  fenc=$(mktemp)
+  base64 "$f" >"$fenc"
+  filetmp=$(mktemp)
+  awk -v file="$fenc" -v mime="$mime" -v filename="$filename" "$AWK_ATTACH" "$fpath" >"$filetmp"
+  mv "$filetmp" "$fpath"
+  if [ -n "${GIT:-}" ]; then
+    $GIT add "$fpath"
+    $GIT commit -q -m "Added attachment to '$(__summary_for_commit "$fpath") ...'" -- "$fpath"
+  fi
+  rm "$fenc"
+}

src/sh/load.sh

@@ -0,0 +1,41 @@
+# Loading functions
+# - __load_approx_data
+# - __load_weeks
+# - __refresh_data
+
+# Print approximate data from iCalendar files in `$ROOT`
+__load_approx_data() {
+  find "$ROOT" -type f -name '*.ics' -print0 |
+    xargs -0 -P0 \
+      awk \
+      -v collection_labels="$COLLECTION_LABELS" \
+      "$AWK_APPROX"
+}
+
+# For every relevant week, print associated iCalendar files
+__load_weeks() {
+  dates=$(awk -F'\t' '{ print $2; print $3 }' "$APPROX_DATA_FILE")
+  file_dates=$(mktemp)
+  echo "$dates" | date --file="/dev/stdin" +"%G:%V:" >"$file_dates"
+  awk "$AWK_MERGE" "$file_dates" "$APPROX_DATA_FILE"
+  rm "$file_dates"
+}
+
+# Refresh approximate data and per-week data.
+#
+# This functions stores the output of `__load_approx_data` in the temporary
+# file `$APPROX_DATA_FILE` and the output of `__load_weeks` in the temporary
+# file `@WEEKLY_DATA_FILE`.
+__refresh_data() {
+  if [ -n "${APPROX_DATA_FILE:-}" ]; then
+    rm -f "$APPROX_DATA_FILE"
+  fi
+  if [ -n "${WEEKLY_DATA_FILE:-}" ]; then
+    rm -f "$WEEKLY_DATA_FILE"
+  fi
+  APPROX_DATA_FILE=$(mktemp)
+  __load_approx_data >"$APPROX_DATA_FILE"
+  WEEKLY_DATA_FILE=$(mktemp)
+  __load_weeks >"$WEEKLY_DATA_FILE"
+  trap 'rm -f "$APPROX_DATA_FILE" "$WEEKLY_DATA_FILE"' EXIT INT
+}

src/sh/misc.sh

@@ -0,0 +1,27 @@
+# err()
+# This is a helper function to print errors.
+#
+# @input $1: Error message
+err() {
+  echo "❌ $1" >/dev/tty
+}
+
+# Print date or datetime in a human and machine readable form.
+#
+# @input $1: Seconds since epoch
+__datetime_human_machine() {
+  s="$1"
+  t=$(date -d "@$s" +"%R")
+  dfmt="%F"
+  if [ "$t" != "00:00" ]; then
+    dfmt="$dfmt %R"
+  fi
+  date -d "@$s" +"$dfmt"
+}
+
+# Get summary string that can be used in for git-commit messages.
+#
+# @input $1: iCalendar file path
+__summary_for_commit() {
+  awk -v field="SUMMARY" "$AWK_GET" "$1" | tr -c -d "[:alnum:][:blank:]" | head -c 15
+}

src/sh/preview.sh

@@ -0,0 +1,51 @@
+# Preview helper functions
+# - month_previous
+# - month_next
+# - datetime_str
+
+# Print previous month of specified input month as <month> <year>.
+#
+# @input $1: Month
+# @input $2: Year
+month_previous() {
+  month=$(echo "$1" | sed 's/^0//')
+  year=$(echo "$2" | sed 's/^0//')
+  if [ "$month" -eq 1 ]; then
+    month=12
+    year=$((year - 1))
+  else
+    month=$((month - 1))
+  fi
+  echo "$month $year"
+}
+
+# Print next month of specified input month as <month> <year>.
+#
+# @input $1: Month
+# @input $2: Year
+month_next() {
+  month=$(echo "$1" | sed 's/^0//')
+  year=$(echo "$2" | sed 's/^0//')
+  if [ "$month" -eq 12 ]; then
+    month=1
+    year=$((year + 1))
+  else
+    month=$((month + 1))
+  fi
+  echo "$month $year"
+}
+
+# Print date or datetime in a human readable form.
+#
+# @input $1:              Seconds since epoch
+# @input $2.. (optoinal): Prepend date format
+datetime_str() {
+  s="$1"
+  shift
+  t=$(date -d "@$s" +"%R")
+  dfmt="$*%e %b %Y"
+  if [ "$t" != "00:00" ]; then
+    dfmt="$dfmt %R %Z"
+  fi
+  date -d "@$s" +"$dfmt"
+}

src/sh/theme.sh

@@ -0,0 +1,8 @@
+GREEN="\033[1;32m"
+RED="\033[1;31m"
+WHITE="\033[1;97m"
+CYAN="\033[1;36m"
+STRIKE="\033[9m"
+ITALIC="\033[3m"
+FAINT="\033[2m"
+OFF="\033[m"

src/sh/view.sh

@@ -0,0 +1,136 @@
+# View Functions
+# - __view_day
+# - __view_week
+# - __view_all
+
+# This function prints the view for the day specified in `$DISPLAY_DATE`, in
+# the tab-delimited format with the fields:
+#  1. start date
+#  2. start time
+#  3. end time
+#  4. file path
+#  5. collection
+#  6. description
+__view_day() {
+  weeknr=$(date -d "$DISPLAY_DATE" +"%G:%V:")
+  files=$(grep "^$weeknr" "$WEEKLY_DATA_FILE" | cut -f 2)
+  # Find relevant files in list of week files
+  sef=$({
+    set -- $files
+    for file in "$@"; do
+      file="$ROOT/$file"
+      awk \
+        -v collection_labels="$COLLECTION_LABELS" \
+        "$AWK_PARSE" "$file"
+    done
+  })
+  # $sef holds (space-delimited): <start> <end> <fpath> <collection> <status> <summary>
+  today=$(date -d "$DISPLAY_DATE" +"%D")
+  if [ -n "$sef" ]; then
+    sef=$(echo "$sef" | while IFS= read -r line; do
+      set -- $line
+      starttime="$1"
+      shift
+      endtime="$1"
+      shift
+      fpath="$1" # we will use | as delimiter (need to convert back!)
+      shift
+      collection="$1"
+      shift
+      status="$1"
+      shift
+      description="$*"
+      #
+      daystart=$(date -d "$today 00:00:00" +"%s")
+      dayend=$(date -d "$today 23:59:59" +"%s")
+      line=""
+      if [ "$starttime" -gt "$daystart" ] && [ "$starttime" -lt "$dayend" ]; then
+        s=$(date -d "@$starttime" +"%R")
+      elif [ "$starttime" -le "$daystart" ] && [ "$endtime" -gt "$daystart" ]; then
+        s="00:00"
+      else
+        continue
+      fi
+      if [ "$endtime" -gt "$daystart" ] && [ "$endtime" -lt "$dayend" ]; then
+        e=$(date -d "@$endtime" +"%R")
+      elif [ "$endtime" -ge "$dayend" ] && [ "$starttime" -lt "$dayend" ]; then
+        e="00:00"
+      else
+        continue
+      fi
+      printf "%s\t%s\t%s\t%s\t%s\t%s\t%s\%s\n" "$s" "$e" "$starttime" "$endtime" "$fpath" "$collection" "$description" "$status"
+    done)
+  fi
+  echo "$sef" | sort -n | awk -v today="$today" -v daystart="$DAY_START" -v dayend="$DAY_END" "$AWK_DAYVIEW"
+}
+
+# This function prints the view for the week that contains the day specified in `$DISPLAY_DATE`.
+__view_week() {
+  weeknr=$(date -d "$DISPLAY_DATE" +"%G:%V:")
+  files=$(grep "^$weeknr" "$WEEKLY_DATA_FILE" | cut -f 2)
+  dayofweek=$(date -d "$DISPLAY_DATE" +"%u")
+  delta=$((1 - dayofweek))
+  startofweek=$(date -d "$DISPLAY_DATE -$delta days" +"%D")
+  # loop over files
+  sef=$({
+    set -- $files
+    for file in "$@"; do
+      file="$ROOT/$file"
+      awk \
+        -v collection_labels="$COLLECTION_LABELS" \
+        "$AWK_PARSE" "$file"
+    done
+  })
+  if [ -n "$sef" ]; then
+    sef=$(echo "$sef" | while IFS= read -r line; do
+      set -- $line
+      starttime="$1"
+      shift
+      endtime="$1"
+      shift
+      #fpath="$1"
+      shift
+      collection="$1"
+      shift
+      status="$1"
+      shift
+      if [ "$status" = "TENTATIVE" ]; then
+        symb="$FAINT$CYAN"
+      elif [ "$status" = "CANCELLED" ]; then
+        symb="$STRIKE"
+      else
+        symb=""
+      fi
+      description="${symb:-}$*$OFF"
+      for i in $(seq 0 7); do
+        daystart=$(date -d "$startofweek +$i days 00:00:00" +"%s")
+        dayend=$(date -d "$startofweek +$i days 23:59:59" +"%s")
+        if [ "$starttime" -gt "$daystart" ] && [ "$starttime" -lt "$dayend" ]; then
+          s=$(date -d "@$starttime" +"%H:%M")
+        elif [ "$starttime" -le "$daystart" ] && [ "$endtime" -gt "$daystart" ]; then
+          s="00:00"
+        else
+          continue
+        fi
+        if [ "$endtime" -gt "$daystart" ] && [ "$endtime" -lt "$dayend" ]; then
+          e=$(date -d "@$endtime" +"%H:%M")
+        elif [ "$endtime" -ge "$dayend" ] && [ "$starttime" -lt "$dayend" ]; then
+          e="00:00"
+        else
+          continue
+        fi
+        printf "%s\t%s\t%s\t%s\n" "$i" "$s" "$e" "$description"
+      done
+    done)
+  fi
+  sef=$({
+    echo "$sef"
+    seq 0 7
+  } | sort -n)
+  echo "$sef" | awk -v startofweek="$startofweek" "$AWK_WEEKVIEW"
+}
+
+# This function prints all entries.
+__view_all() {
+  cat "$APPROX_DATA_FILE"
+}