Add waybar theming to processors

theme_waybar

@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+readonly dependency=("mnussbaum/base16-waybar")
+readonly app="waybar"
+
+path="$1"
+package="$2"
+theme="$3"
+permanent="$4"
+
+## Main Entrypoint
+#
+#  Finds the right theme template file and starts theme
+#  switching and, if necessary, permanent setting processes.
+main() {
+    dbg_msg $app "Starting Processor"
+    tfile="$path/$package/colors/base16-$theme.css"
+
+    if ! file_exists "$tfile"; then
+        dbg_msg $app "error" "Theme template $theme not found in package $package"
+        exit 1
+    fi
+
+    if [[ "$permanent" == "true" ]]; then save; fi
+    # theme
+
+    dbg_msg $app "Processor Done"
+}
+
+## Theme setter
+#
+#  Takes care of permanently writing the desired
+#  base16 theme into application settings.
+save() {
+    dbg_msg $app "Saving theme"
+    local waybar_config_dir="${XDG_CONFIG_HOME:-$HOME/.config}/waybar"
+    local waybar_data_dir="${XDG_DATA_HOME:-$HOME/.local/share}/waybar"
+
+    if [[ ! -d "$waybar_data_dir" ]]; then
+        mkdir -p "$waybar_data_dir"
+        dbg_msg $app "Creating waybar data directory in $waybar_data_dir"
+    fi
+
+    cat "$tfile" >"$waybar_data_dir/colorscheme.css"
+    dbg_msg $app "Saved theme to $waybar_data_dir/colorscheme.css"
+
+    include "$waybar_config_dir" "$waybar_data_dir"
+
+    command -v killall && killall waybar && waybar &
+}
+
+## Theme includer
+#
+#  Makes sure that theme is actually included in
+#  default application startup routine.
+#  This is the most invasive step of theming since it
+#  rewrites within existing configuration files.
+include() {
+    dbg_msg $app "Including theme in configuration"
+    local waybar_config_dir="$1"
+    local waybar_data_dir="$2"
+
+    if file_exists "$waybar_config_dir/style.css"; then
+        line_exists_or_append "$waybar_config_dir/style.css" "@import \"$waybar_data_dir/colorscheme.css\";"
+        dbg_msg $app "Successfully included theme in configuration"
+    else
+        dbg_msg $app "warn" "No default configuration file found"
+    fi
+    dbg_msg $app "Sucessfully included theme"
+}
+
+# Safe sourcing: https://stackoverflow.com/a/12694189
+DIR="${BASH_SOURCE%/*}"
+if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi
+# shellcheck source=utilities.sh
+. "$DIR/utilities.sh"
+## Dependency Checker
+#
+#  Makes sure the processor is called for the correct
+#  base16 package, or refuses to run if it is not.
+if printf '%s\n' "${dependency[@]}" | grep -q -P "^$package$"; then
+    main
+else
+    dbg_msg $app "error" "Processor does not work for package $package"
+fi