#!/usr/bin/env sh
set -eu

ROOT_DIR="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
CALENDAR_DIR="$ROOT_DIR/calendar"
DIST_DIR="$CALENDAR_DIR/dist"
PORT=${PORT:-4173}
SWIFT_SCRIPT="$CALENDAR_DIR/scripts/export-kindle-background.swift"
THEMES_SOURCE="$CALENDAR_DIR/config/themes.json"

THEME_FILTER=""
ORIENTATION_FILTER=""

print_usage() {
  cat <<'EOF'
用法：
  sh scripts/export-theme-backgrounds.sh [选项]

选项：
      --theme <theme-id>         只导出指定主题
      --orientation <value>      只导出指定方向；必须和 --theme 一起使用
  -h, --help                     查看帮助

示例：
  sh scripts/export-theme-backgrounds.sh
  sh scripts/export-theme-backgrounds.sh --theme simple
  sh scripts/export-theme-backgrounds.sh --theme simple --orientation portrait
EOF
}

while [ "$#" -gt 0 ]; do
  case "$1" in
    --theme)
      shift
      THEME_FILTER=${1:?"missing theme id"}
      ;;
    --orientation)
      shift
      ORIENTATION_FILTER=${1:?"missing orientation"}
      ;;
    -h|--help)
      print_usage
      exit 0
      ;;
    *)
      echo "未知参数: $1" >&2
      echo >&2
      print_usage >&2
      exit 1
      ;;
  esac
  shift
done

if [ -n "$ORIENTATION_FILTER" ] && [ -z "$THEME_FILTER" ]; then
  echo "--orientation 必须和 --theme 一起使用。" >&2
  exit 1
fi

selection_output=$(
  node --input-type=module -e "
import fs from 'node:fs';

const data = JSON.parse(fs.readFileSync(process.argv[1], 'utf8'));
const requestedTheme = process.argv[2];
const requestedOrientation = process.argv[3];
const themes = data.themes ?? [];
const themeMap = new Map(themes.map((theme) => [theme.id, theme]));

if (requestedTheme && !themeMap.has(requestedTheme)) {
  console.error(\`未知主题: \${requestedTheme}\`);
  process.exit(1);
}

if (requestedOrientation && !requestedTheme) {
  console.error('--orientation 必须和 --theme 一起使用。');
  process.exit(1);
}

const filteredThemes = requestedTheme ? themes.filter((theme) => theme.id === requestedTheme) : themes;
const items = [];

for (const theme of filteredThemes) {
  const orientations = Object.keys(theme.variants ?? {});
  if (requestedOrientation) {
    if (!orientations.includes(requestedOrientation)) {
      console.error(
        \`主题 \${theme.id} 不支持方向 \${requestedOrientation}，可用方向: \${orientations.join(', ')}\`,
      );
      process.exit(1);
    }
  }

  const filteredOrientations = requestedOrientation ? [requestedOrientation] : orientations;
  for (const orientation of filteredOrientations) {
    const variant = theme.variants[orientation];
    items.push([theme.id, orientation, variant.backgroundPath].join('\t'));
  }
}

if (items.length === 0) {
  console.error('没有可导出的主题背景。');
  process.exit(1);
}

console.log(\`DEFAULT_THEME_ID=\${data.defaultThemeId}\`);
console.log(\`DEFAULT_ORIENTATION=\${data.defaultOrientation}\`);
for (const item of items) {
  console.log(\`ITEM=\${item}\`);
}
" "$THEMES_SOURCE" "$THEME_FILTER" "$ORIENTATION_FILTER"
)

DEFAULT_THEME_ID=""
DEFAULT_ORIENTATION=""
EXPORT_ITEMS=""

while IFS= read -r line; do
  case "$line" in
    DEFAULT_THEME_ID=*)
      DEFAULT_THEME_ID=${line#DEFAULT_THEME_ID=}
      ;;
    DEFAULT_ORIENTATION=*)
      DEFAULT_ORIENTATION=${line#DEFAULT_ORIENTATION=}
      ;;
    ITEM=*)
      if [ -n "$EXPORT_ITEMS" ]; then
        EXPORT_ITEMS="${EXPORT_ITEMS}
${line#ITEM=}"
      else
        EXPORT_ITEMS=${line#ITEM=}
      fi
      ;;
  esac
done <<EOF
$selection_output
EOF

if [ -z "$DEFAULT_THEME_ID" ] || [ -z "$DEFAULT_ORIENTATION" ] || [ -z "$EXPORT_ITEMS" ]; then
  echo "无法解析导出目标。" >&2
  exit 1
fi

cd "$CALENDAR_DIR"
npm run build >/dev/null

python3 -m http.server "$PORT" -d "$DIST_DIR" >/tmp/kindle-calendar-http.log 2>&1 &
SERVER_PID=$!
trap 'kill "$SERVER_PID" 2>/dev/null || true' EXIT INT TERM

sleep 1

printf '%s\n' "$EXPORT_ITEMS" | while IFS="$(printf '\t')" read -r theme_id orientation background_path; do
  out_png="$DIST_DIR/$background_path"
  out_region="${out_png%.png}.clock-region.json"
  url="http://127.0.0.1:$PORT/?mode=background&theme=$theme_id&orientation=$orientation"
  /usr/bin/swift "$SWIFT_SCRIPT" "$url" "$out_png" "$out_region" >/dev/null

  # 根目录的 kindlebg.png / clock-region.json 只给默认主题兜底使用。
  # 定向导出其它主题时不覆盖它，避免把默认主题的运行时入口意外改掉。
  if [ "$theme_id" = "$DEFAULT_THEME_ID" ] && [ "$orientation" = "$DEFAULT_ORIENTATION" ]; then
    cp "$out_png" "$DIST_DIR/kindlebg.png"
    cp "$out_region" "$DIST_DIR/clock-region.json"
  fi

  printf 'Exported %s %s -> %s\n' "$theme_id" "$orientation" "$out_png"
done

node "$CALENDAR_DIR/scripts/generate-dashboard-manifest.mjs" >/dev/null

if [ -f "$DIST_DIR/clock-region.json" ]; then
  printf 'Default region saved to %s\n' "$DIST_DIR/clock-region.json"
else
  printf 'Skipped default region update (default theme not exported this run)\n'
fi