/**
 * Storage의 reward-products/ 이미지 전체를 리사이즈 + WebP로 일괄 최적화한다.
 * 같은 오브젝트 경로에 덮어쓰고 다운로드 토큰을 보존하므로 Firestore에 저장된 URL은 그대로 유효하다.
 * 실행: npm run optimize:reward-images
 */
import { execFileSync, execSync } from "node:child_process";
import { OPTIMIZED_FLAG, optimizeRewardImage, targetForPath } from "../src/services/imageOptimizeService";

const storageBucket = "mmday-panit.firebasestorage.app";

const accessToken = (process.platform === "win32" ?
  execSync("gcloud auth print-access-token", { encoding: "utf8", windowsHide: true }) :
  execFileSync("gcloud", ["auth", "print-access-token"], { encoding: "utf8", windowsHide: true })).trim();

const apiBase = `https://storage.googleapis.com/storage/v1/b/${storageBucket}/o`;
const uploadBase = `https://storage.googleapis.com/upload/storage/v1/b/${storageBucket}/o`;
const authHeader = { Authorization: `Bearer ${accessToken}` };

interface StorageObject {
  name: string;
  size: string;
  contentType?: string;
  metadata?: Record<string, string>;
}

async function listObjects(): Promise<StorageObject[]> {
  const items: StorageObject[] = [];
  let pageToken: string | undefined;
  do {
    const params = new URLSearchParams({
      prefix: "reward-products/",
      fields: "items(name,size,contentType,metadata),nextPageToken",
    });
    if (pageToken) params.set("pageToken", pageToken);
    const res = await fetch(`${apiBase}?${params}`, { headers: authHeader });
    if (!res.ok) throw new Error(`list failed: ${res.status} ${await res.text()}`);
    const body = await res.json() as { items?: StorageObject[]; nextPageToken?: string };
    items.push(...(body.items ?? []));
    pageToken = body.nextPageToken;
  } while (pageToken);
  return items;
}

async function download(name: string): Promise<Buffer> {
  const res = await fetch(`${apiBase}/${encodeURIComponent(name)}?alt=media`, { headers: authHeader });
  if (!res.ok) throw new Error(`download failed for ${name}: ${res.status}`);
  return Buffer.from(await res.arrayBuffer());
}

async function markOptimized(name: string): Promise<void> {
  const res = await fetch(`${apiBase}/${encodeURIComponent(name)}`, {
    method: "PATCH",
    headers: { ...authHeader, "Content-Type": "application/json" },
    body: JSON.stringify({ metadata: { [OPTIMIZED_FLAG]: "true" } }),
  });
  if (!res.ok) throw new Error(`metadata patch failed for ${name}: ${res.status} ${await res.text()}`);
}

/** multipart 업로드로 본문과 메타데이터(토큰 보존 + 최적화 플래그)를 한 번에 교체한다. */
async function overwrite(obj: StorageObject, data: Buffer): Promise<void> {
  const boundary = "reward-image-optimize-boundary";
  const metadata = {
    name: obj.name,
    contentType: "image/webp",
    metadata: { ...(obj.metadata ?? {}), [OPTIMIZED_FLAG]: "true" },
  };
  const body = Buffer.concat([
    Buffer.from(
      `--${boundary}\r\nContent-Type: application/json; charset=UTF-8\r\n\r\n` +
      `${JSON.stringify(metadata)}\r\n` +
      `--${boundary}\r\nContent-Type: image/webp\r\n\r\n`),
    data,
    Buffer.from(`\r\n--${boundary}--`),
  ]);
  const res = await fetch(`${uploadBase}?uploadType=multipart`, {
    method: "POST",
    headers: { ...authHeader, "Content-Type": `multipart/related; boundary=${boundary}` },
    body,
  });
  if (!res.ok) throw new Error(`upload failed for ${obj.name}: ${res.status} ${await res.text()}`);
}

async function main() {
  const objects = await listObjects();
  let before = 0;
  let after = 0;
  for (const obj of objects) {
    const size = Number(obj.size);
    const target = targetForPath(obj.name);
    if (!target) { console.log(`skip (path)      ${obj.name}`); continue; }
    if (obj.metadata?.[OPTIMIZED_FLAG] === "true") {
      console.log(`skip (done)      ${obj.name}`);
      before += size; after += size;
      continue;
    }
    const input = await download(obj.name);
    const output = await optimizeRewardImage(input, target);
    before += size;
    if (output.data.length >= input.length) {
      await markOptimized(obj.name);
      after += size;
      console.log(`skip (small)     ${obj.name} ${(size / 1024).toFixed(0)}KB`);
      continue;
    }
    await overwrite(obj, output.data);
    after += output.data.length;
    console.log(
      `optimized        ${obj.name} ` +
      `${(size / 1048576).toFixed(1)}MB -> ${(output.data.length / 1024).toFixed(0)}KB ` +
      `(${output.width}x${output.height})`);
  }
  console.log(`\nTOTAL ${objects.length} files: ${(before / 1048576).toFixed(1)}MB -> ${(after / 1048576).toFixed(1)}MB`);
}

main().catch((err) => { console.error(err); process.exit(1); });