/**
 * media.ts 單元測試（塊 3）
 *
 * 驗證：
 *   - validateImageFile / validateVideoFile / validateBatchFiles 各種通過 / 失敗路徑
 *   - buildBatchImageUrl 組路徑（含 / 不含 cacheBust）
 *   - uploadImage / uploadBatchImages / seekVideo 打對的路徑與 FormData 欄位
 *     （mock XMLHttpRequest + api.post）
 */
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";

import {
  MAX_BATCH_IMAGES,
  MAX_VIDEO_BYTES,
  VIDEO_FALLBACK_FPS,
  buildBatchImageUrl,
  frameToSeekSeconds,
  seekVideo,
  uploadBatchImages,
  uploadImage,
  validateBatchFiles,
  validateImageFile,
  validateVideoFile,
} from "./media";

function makeFile(name: string, sizeBytes = 1024): File {
  const blob = new Blob([new Uint8Array(sizeBytes)], { type: "application/octet-stream" });
  return new File([blob], name);
}

/**
 * 建立「宣稱」指定 size 的 File，但不實際配置該大小的記憶體。
 * 用於大檔邊界測試（500 MB 若真配置 Uint8Array 會 OOM）——只覆寫 File.size getter。
 */
function makeSizedFile(name: string, sizeBytes: number): File {
  const file = new File([new Blob([new Uint8Array(8)])], name);
  Object.defineProperty(file, "size", { value: sizeBytes, configurable: true });
  return file;
}

describe("media validation", () => {
  it("圖片：JPG/PNG 通過，其他型別擋 TYPE", () => {
    expect(validateImageFile(makeFile("a.jpg"))).toBeNull();
    expect(validateImageFile(makeFile("a.jpeg"))).toBeNull();
    expect(validateImageFile(makeFile("a.PNG"))).toBeNull();
    expect(validateImageFile(makeFile("a.gif"))?.code).toBe("TYPE");
    expect(validateImageFile(makeFile("a.mp4"))?.code).toBe("TYPE");
  });

  it("圖片：超過 20 MB 擋 SIZE", () => {
    const big = makeFile("a.jpg", 21 * 1024 * 1024);
    expect(validateImageFile(big)?.code).toBe("SIZE");
  });

  it("影片：MP4/AVI/MOV/MPEG 通過，其他擋 TYPE", () => {
    expect(validateVideoFile(makeFile("v.mp4"))).toBeNull();
    expect(validateVideoFile(makeFile("v.mov"))).toBeNull();
    expect(validateVideoFile(makeFile("v.mpeg"))).toBeNull();
    expect(validateVideoFile(makeFile("v.jpg"))?.code).toBe("TYPE");
  });

  it("影片：上限為 500 MB（常數校驗）", () => {
    expect(MAX_VIDEO_BYTES).toBe(500 * 1024 * 1024);
  });

  it("影片：499 MB 通過，剛好 500 MB 通過，501 MB 擋 SIZE（邊界）", () => {
    const mb = 1024 * 1024;
    expect(validateVideoFile(makeSizedFile("v.mp4", 499 * mb))).toBeNull();
    // 剛好等於上限：validateVideoFile 用 > 判斷，等於上限應通過
    expect(validateVideoFile(makeSizedFile("v.mp4", 500 * mb))).toBeNull();
    expect(validateVideoFile(makeSizedFile("v.mp4", 501 * mb))?.code).toBe("SIZE");
  });

  it("批次：空陣列 → EMPTY，超過 50 → COUNT，含非圖 → TYPE", () => {
    expect(validateBatchFiles([])?.code).toBe("EMPTY");

    const tooMany = Array.from({ length: MAX_BATCH_IMAGES + 1 }, (_, i) =>
      makeFile(`img${i}.jpg`),
    );
    expect(validateBatchFiles(tooMany)?.code).toBe("COUNT");

    expect(
      validateBatchFiles([makeFile("ok.jpg"), makeFile("bad.txt")])?.code,
    ).toBe("TYPE");

    expect(validateBatchFiles([makeFile("a.jpg"), makeFile("b.png")])).toBeNull();
  });
});

describe("frameToSeekSeconds", () => {
  it("有 durationSeconds + totalFrames → 用 duration 換算（不依賴 fps）", () => {
    // 100 frames / 10 秒 → frame 50 = 5 秒
    expect(frameToSeekSeconds(50, 100, 10)).toBe(5);
    // frame 0 = 0 秒
    expect(frameToSeekSeconds(0, 100, 10)).toBe(0);
    // 換算與 fps 常數無關：即使 fps 常數是 15，這裡仍用 duration
    expect(frameToSeekSeconds(30, 60, 12)).toBe(6);
  });

  it("缺 durationSeconds → 退用具名 fps 常數（frame / VIDEO_FALLBACK_FPS）", () => {
    expect(frameToSeekSeconds(30, 100, undefined)).toBe(30 / VIDEO_FALLBACK_FPS);
    // duration <= 0 也視為缺
    expect(frameToSeekSeconds(30, 100, 0)).toBe(30 / VIDEO_FALLBACK_FPS);
  });

  it("缺 totalFrames → 退用 fps 常數", () => {
    expect(frameToSeekSeconds(45, undefined, 10)).toBe(45 / VIDEO_FALLBACK_FPS);
  });

  it("負 frame → clamp 為 0", () => {
    expect(frameToSeekSeconds(-5, 100, 10)).toBe(0);
    expect(frameToSeekSeconds(-5, undefined, undefined)).toBe(0);
  });
});

describe("buildBatchImageUrl", () => {
  // jsdom 有 window 且未設 NEXT_PUBLIC_API_BASE → getApiBaseUrl 回 ""（同 origin 相對路徑）
  it("組出 /api/media/batch-images/:index（無 cacheBust）", () => {
    expect(buildBatchImageUrl(3)).toBe("/api/media/batch-images/3");
  });

  it("帶 cacheBust 加上 _t query", () => {
    expect(buildBatchImageUrl(0, "abc")).toBe("/api/media/batch-images/0?_t=abc");
  });
});

/* -------------------------------------------------------------------------- */
/* Upload（mock XMLHttpRequest）                                              */
/* -------------------------------------------------------------------------- */

interface FakeXHR {
  method?: string;
  url?: string;
  withCredentials?: boolean;
  timeout?: number;
  sent?: FormData;
  status: number;
  responseText: string;
  upload: { onprogress: ((ev: ProgressEvent) => void) | null };
  onload: (() => void) | null;
  onerror: (() => void) | null;
  ontimeout: (() => void) | null;
  open(method: string, url: string): void;
  send(body: FormData): void;
  abort(): void;
}

let lastXhr: FakeXHR | null = null;

function installXhrMock(responder: (xhr: FakeXHR) => void) {
  // 以工廠回傳 plain object（closure over `xhr`），避免 class + `this` 別名（no-this-alias）。
  function XHRMock(this: unknown) {
    const xhr: FakeXHR = {
      withCredentials: false,
      timeout: 0,
      status: 200,
      responseText: "",
      upload: { onprogress: null },
      onload: null,
      onerror: null,
      ontimeout: null,
      open(method: string, url: string) {
        xhr.method = method;
        xhr.url = url;
      },
      send(body: FormData) {
        xhr.sent = body;
        queueMicrotask(() => responder(xhr));
      },
      abort() {},
    };
    lastXhr = xhr;
    return xhr;
  }
  (globalThis as { XMLHttpRequest?: unknown }).XMLHttpRequest =
    XHRMock as unknown as typeof XMLHttpRequest;
}

describe("uploadImage / uploadBatchImages（XHR mock）", () => {
  const origXHR = globalThis.XMLHttpRequest;
  beforeEach(() => {
    lastXhr = null;
  });
  afterEach(() => {
    (globalThis as { XMLHttpRequest?: unknown }).XMLHttpRequest = origXHR;
  });

  it("uploadImage：POST /api/media/upload/image、帶 deviceId+file、回傳 data", async () => {
    installXhrMock((xhr) => {
      xhr.status = 200;
      xhr.responseText = JSON.stringify({
        success: true,
        data: { streamUrl: "/api/camera/stream", sourceType: "image", filename: "a.jpg" },
      });
      xhr.onload?.();
    });

    const res = await uploadImage("dev-1", makeFile("a.jpg"));
    expect(res.sourceType).toBe("image");
    expect(res.streamUrl).toBe("/api/camera/stream");
    expect(lastXhr?.method).toBe("POST");
    expect(lastXhr?.url).toContain("/api/media/upload/image");
    expect(lastXhr?.withCredentials).toBe(true);
    expect(lastXhr?.sent?.get("deviceId")).toBe("dev-1");
    expect(lastXhr?.sent?.get("file")).toBeInstanceOf(File);
  });

  it("uploadBatchImages：多檔以 files 欄位附加", async () => {
    installXhrMock((xhr) => {
      xhr.status = 200;
      xhr.responseText = JSON.stringify({
        success: true,
        data: { streamUrl: "/api/camera/stream", sourceType: "batch_image", totalImages: 2 },
      });
      xhr.onload?.();
    });

    const res = await uploadBatchImages("dev-1", [makeFile("a.jpg"), makeFile("b.png")]);
    expect(res.totalImages).toBe(2);
    expect(lastXhr?.url).toContain("/api/media/upload/batch-images");
    expect(lastXhr?.sent?.getAll("files")).toHaveLength(2);
  });

  it("非 2xx 且有 error envelope → 拋 ApiError（保留 code）", async () => {
    installXhrMock((xhr) => {
      xhr.status = 400;
      xhr.responseText = JSON.stringify({
        success: false,
        error: { code: "BAD_REQUEST", message: "only JPG/PNG files are supported" },
      });
      xhr.onload?.();
    });

    await expect(uploadImage("dev-1", makeFile("a.jpg"))).rejects.toMatchObject({
      code: "BAD_REQUEST",
      status: 400,
    });
  });

  it("回報上傳進度", async () => {
    installXhrMock((xhr) => {
      xhr.upload.onprogress?.({ lengthComputable: true, loaded: 50, total: 100 } as ProgressEvent);
      xhr.status = 200;
      xhr.responseText = JSON.stringify({
        success: true,
        data: { streamUrl: "/s", sourceType: "image" },
      });
      xhr.onload?.();
    });

    const onProgress = vi.fn();
    await uploadImage("dev-1", makeFile("a.jpg"), { onProgress });
    expect(onProgress).toHaveBeenCalledWith(50);
  });
});

describe("seekVideo", () => {
  it("POST /api/media/seek，body 帶 timeSeconds", async () => {
    const apiModule = await import("@/lib/api");
    const spy = vi
      .spyOn(apiModule.api, "post")
      .mockResolvedValue({ seekTo: 3, frameOffset: 45 } as never);

    const res = await seekVideo(3);
    expect(spy).toHaveBeenCalledWith("/api/media/seek", { timeSeconds: 3 });
    expect(res).toEqual({ seekTo: 3, frameOffset: 45 });
    spy.mockRestore();
  });
});