feat: html rendering

src/sh/preview.sh

@@ -0,0 +1,21 @@
+# Preview functions
+
+# Preview email
+# If a thread identifier is given, then the last message in the thread is
+# shown. If the HTML flag is set, then the HTML message is parsed using pandoc.
+# This functions reverts to the HTML method if no HTML flag is set yet no
+# text/plain part is found.
+#
+# @argument $1: "id" or "thread"
+# @argument $2: message id or thread id
+# @argument #3: if set, then the HTML messages will be taken
+preview_message() {
+  [ "$1" = "id" ] && messageid="$2" || messageid="$(nm_last_message_in_thread "$2")"
+  parts="$(nm_message_parts "$messageid")"
+  html="${3:-}"
+  nr="$(nm_message_part_nr "$messageid" "$html")"
+  [ ! "$nr" ] && [ ! "$html" ] && html="html" && nr="$(nm_message_part_nr "$messageid" "html")"
+  [ "$html" ] && parser="$PANDOC" || parser="cat"
+  nm_message_header "$messageid" | $CATEMAIL
+  nm_message_get_part "$messageid" "$nr" | $parser | $CATMD
+}