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[khome.git] / home / bin / wallpapers_preview

diff --git a/home/bin/wallpapers_preview b/home/bin/wallpapers_preview
index b5672d8..8727517 100755 (executable)
--- a/home/bin/wallpapers_preview
+++ b/home/bin/wallpapers_preview
@@ -1,10 +1,99 @@
-#! /bin/sh
+#! /bin/bash
 
-case "$1" in
-    '') dir="$DIR_WALLPAPERS";;
-    *) dir="$1";;
-esac
+### XXX Chose not to 'set -e' because arithmetic evaluation can cause a non-zero exit.
+### XXX Chose not to 'set -u' because unset params ($1, $2, ...) cause failures.
+### Solutions to the above are ugly.
 
-# XXX Apparently injecting a filepath with {} is bad: https://github.com/koalaman/shellcheck/wiki/SC2156
-#find "$dir" -type f -exec bash -c 'feh --bg-scale "{}"; read' \;
-find "$dir" -type f -exec bash -c 'feh --bg-scale "$1"; read' shell '{}' \;
+declare -a paths
+declare -i n=0
+
+read_command() {
+    local char
+
+    read -rsn 1 char
+    case "$char" in
+        q | Q) echo 'CMD_QUIT';;
+        h | H) echo 'CMD_MOVE_BACK';;
+        l | L) echo 'CMD_MOVE_FORWARD';;
+        f | F) echo 'CMD_FAVORITE';;
+            *) echo 'CMD_UKNOWN';;
+    esac
+}
+
+paths_set() {
+    local path
+
+    while read -r path
+    do
+        if file "$path" | grep 'image data' > /dev/null
+        then
+            (( n++ ))
+            # \r jumps to the beginning of the line:
+            printf '\rFound %d images.' "$n" >&2
+            paths["$(( n - 1 ))"]="$path"
+        fi
+    done
+    printf '\n' >&2
+}
+
+paths_set_from_dir_find() {
+    paths_set < <(find "$1" -type f)
+}
+
+paths_set_from_favs() {
+    paths_set < <(sort -k 2 "$FILE_WALLPAPER_FAVS" | awk '{sub("^" $1 " +", ""); print}')
+}
+
+set_wallpaper() {
+    local -ri i="$1"
+    local -r path="$2"
+
+    printf '%d of %d %s\n' "$(( i + 1 ))" "$n" "$path"
+    feh --bg-scale "$path"
+}
+
+paths_preview() {
+    local -i i=0
+    local path="${paths[$i]}"
+
+    set_wallpaper "$i" "$path"
+
+    while :
+    do
+        if [[ "${paths[$i]}" != "$path" ]]
+        then
+            path="${paths[$i]}"
+            set_wallpaper "$i" "$path"
+        fi
+
+        case "$(read_command)" in
+            CMD_QUIT)
+                exit 0;;
+            CMD_MOVE_BACK)
+                (( i = i == 0 ? (n - 1) : i - 1));;
+            CMD_MOVE_FORWARD)
+                (( i = (i + 1) % n ));;
+            CMD_FAVORITE)
+                wallpaper_fav;;
+            CMD_UKNOWN)
+                continue;;
+        esac
+    done
+}
+
+main() {
+    case "$1" in
+        f | fav) paths_set_from_favs;;
+        d | dir) paths_set_from_dir_find "$2";;
+        a | all) paths_set_from_dir_find "$DIR_WALLPAPERS";;
+        '')
+            paths_set_from_dir_find "$DIR_WALLPAPERS";;
+        *)
+            printf 'Error: unknown source "%s"\n' "$1" >&2
+            exit 1;;
+    esac
+
+    paths_preview
+}
+
+main "$@"