add thekno-chameleon utility script

.editorconfig

@@ -11,3 +11,7 @@ insert_final_newline = true
 [{Makefile,debian/rules,make.d/*}]
 indent_style = tab
 indent_size = 4
+
+[*.sh]
+indent_style = tab
+indent_size = 4

.gitignore

@@ -10,3 +10,12 @@
 
 # Log files
 npm-debug.log*
+
+# debian build files
+debian/.debhelper/
+debian/debhelper-build-stamp
+debian/files
+debian/tmp/
+debian/*.substvars
+debian/thekno/
+debian/thekno-chameleon/

debian/control

@@ -2,14 +2,30 @@ Source: thekno
 Section: web
 Priority: optional
 Maintainer: Konrad Mohrfeldt <konrad.mohrfeldt@farbdev.org>
-Standards-Version: 4.3.0
+Standards-Version: 4.4.0
 Build-Depends: debhelper (>= 9), dh-exec, nodejs, npm
 Homepage: https://git.hack-hro.de/lohro/lohrothek/thekno
 
 Package: thekno
 Architecture: all
-Depends: ${misc:Depends}
+Depends:
+ ${misc:Depends},
+Suggests:
+ ${misc:Suggests},
+ thekno-chameleon,
 Description: Vue-based music player app based on the lohrothek-api
  Thekno is a frontend and music player for the lohrothek-api backend.
  It is designed as a Progressive Web App (PWA) and optimized for
  mobile devices and desktops.
+
+Package: thekno-chameleon
+Architecture: all
+Depends:
+ ${misc:Depends},
+ jo,
+ imagemagick,
+ optipng,
+ wget,
+Description: Helper util for generating branded thekno apps.
+ thekno-chameleon uses thekno’s environment configuration to produce
+ a PWA manifest and other assets.

debian/rules

@@ -3,12 +3,13 @@
 #export DH_VERBOSE=1
 
 %:
-	dh $@ --package=thekno
+	dh $@ --package thekno
+	dh $@ --package thekno-chameleon
 
 override_dh_auto_build:
 	true
 
 override_dh_auto_install:
-	dh_auto_install --package thekno -- install
+	dh_auto_install --package thekno --destdir debian/thekno -- install
 
 # vim:ft=make:

debian/thekno-chameleon.install

+#!/usr/bin/dh-exec
+scripts/thekno-chameleon.sh => /usr/bin/thekno-chameleon

debian/thekno.docs

 README.md
+docs/environment-configuration.md

scripts/thekno-chameleon.sh

+#!/bin/dash
+
+set -eu
+
+if [ "$#" -ne 3 ]; then
+	cat <<-EOF >&2
+		Usage: $0 ENV_FILE BASE_URL DEST_DIR
+
+
+		ENV_FILE:
+		    The thekno-env JSON file according to the environment configuration
+		    specification. For thekno-chameleon to run take extra care of the
+		    integration property.
+
+		BASE_URL:
+		    The domain you’re using for your app. This will be used to prefix
+		    icon URLs as they have to be absolute.
+
+		DEST_DIR:
+		    The directory to write the files to. This includes icon/logo files and
+		    the PWA manifest.
+EOF
+	exit 1
+fi
+
+ENV_FILE=$1
+BASE_URL=$2
+DEST_DIR=$(realpath "$3")
+THEME_COLOR="#24242e"
+
+LOGO_URL=$(jq -r '.integration.logo' "$ENV_FILE")
+LOGO="$DEST_DIR/$(basename "$LOGO_URL")"
+NAME=$(jq -r '.name' "$ENV_FILE")
+SHORT_NAME=$(jq -r '.integration.shortName' "$ENV_FILE")
+BACKGROUND_COLOR=$(jq -r ".integration.splashBackground // \"$THEME_COLOR\"" "$ENV_FILE")
+DESCRIPTION=$(jq -r '.description' "$ENV_FILE")
+
+mkdir -p "$DEST_DIR"
+wget -q -O "$LOGO" "$LOGO_URL"
+
+render_image() {
+	local src dest format size
+	src=$1
+	dest=$2
+	format=$3
+	size=$4
+
+	if [ "$format" = webp ]; then
+		convert -density "$(($size * 3))" -define webp:lossless=true -background none -resize "${size}x" "$src" "$format:$dest"
+	else
+		cairosvg --format png --output-width "$size" --output-height "$size" --output "$dest" "$src" 2>/dev/null || \
+			convert -density "$(($size * 6))" -background none -resize "${size}x" "$src" "$format:$dest"
+	fi
+}
+
+render_logo() {
+	{
+		local target_file
+		# emit the svg logo first
+		jo src="$BASE_URL/~local/$(basename "$LOGO")" type="image/svg" sizes="512x512"
+		for size in 32 48 96 144 192 256 512; do
+			for format in png webp; do
+				echo "rendering logo to ${size}x${size} as $format" >&2
+				target_file=$DEST_DIR/$(basename "${LOGO%.svg}")_$size.$format
+				render_image "$LOGO" "$target_file" "$format" "$size" >/dev/null
+				[ "$format" = 'png' ] && optipng -o7 -quiet -clobber "$target_file"
+				jo src="$BASE_URL/~local/$(basename "$target_file")" type="image/$format" sizes="${size}x${size}"
+			done
+		done
+	} | jo -a
+}
+
+jo \
+	name="$NAME" \
+	short_name="$SHORT_NAME" \
+	background_color="$BACKGROUND_COLOR" \
+	theme_color="$THEME_COLOR" \
+	description="$DESCRIPTION" \
+	icons="$(render_logo)" \
+	display=standalone \
+	start_url=/ \
+	categories="$(jo -a entertainment music)" \
+	orientation=portrait-primary >"$DEST_DIR/manifest.json"
+
+cat <<-EOF >&2
+Logo files and PWA manifest have been generated in the "$DEST_DIR" directory.
+Please add the following section to your NGINX configuration:
+
+EOF
+
+cat <<-EOF
+location /~local/ {
+	alias "$DEST_DIR/";
+	add_header Cache-Control "public, no-cache";
+}
+EOF