#!/usr/bin/env bash
# Renders the three app-icon variants from appicon.html into the asset catalog.
#
#   scripts/appicon/generate.sh
#
# Chrome is the rasteriser because it is the only thing on a stock Mac that
# renders SVG the same way the browser preview sheets in docs/ do. The PNGs it
# writes are build output — edit appicon.html, not them.
set -euo pipefail

HERE="$(cd "$(dirname "$0")" && pwd)"
OUT="$HERE/../../Marks/Assets.xcassets/AppIcon.appiconset"
CHROME="/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"

[ -x "$CHROME" ] || { echo "Google Chrome not found at $CHROME" >&2; exit 1; }
command -v magick >/dev/null || { echo "ImageMagick (magick) not found" >&2; exit 1; }

render() {
  local variant=$1 name=$2
  "$CHROME" --headless=new --disable-gpu --hide-scrollbars \
    --default-background-color=00000000 \
    --screenshot="$OUT/$name" --window-size=1024,1024 \
    --virtual-time-budget=2000 \
    "file://$HERE/appicon.html?v=$variant" >/dev/null 2>&1
  echo "  $name"
}

echo "rendering app icon ->"
render light  AppIcon.png
render dark   AppIcon-Dark.png
render tinted AppIcon-Tinted.png

# The light icon is the one shipped as the home-screen artwork, and iOS rejects
# an alpha channel there. The dark and tinted variants are composited by the
# system over a background it supplies, so they must keep theirs.
magick "$OUT/AppIcon.png" -background '#F8F5EF' -alpha remove -alpha off "$OUT/AppIcon.png"

echo "done"