import { describe, expect, it } from "vitest";

import { clipboardImageFiles, clipboardImageURL, insertClipboardImageReferences } from "@/lib/client/clipboard-images";

function clipboard(items: Array<{ kind: string; type: string; getAsFile: () => File | null }>, files: File[] = []) {
  return { items, files } as unknown as Pick<DataTransfer, "items" | "files">;
}

function item(file: File | null, type = file?.type || "image/png") {
  return { kind: "file", type, getAsFile: () => file };
}

describe("clipboardImageFiles", () => {
  it("accepts image items and avoids their duplicate files representation", () => {
    const png = new File(["png bytes"], "image", { type: "image/png" });
    const jpeg = new File(["jpeg bytes"], "photo.jpeg", { type: "image/jpeg" });
    const result = clipboardImageFiles(clipboard([item(png), item(jpeg)], [png, jpeg]));

    expect(result).toHaveLength(2);
    expect(result.map((file) => file.name)).toEqual(["pasted-image.png", "photo.jpeg"]);
    expect(result[1]).toBe(jpeg);
    expect(result[0].type).toBe("image/png");
  });

  it("falls back to files when clipboard items do not expose an image", () => {
    const webp = new File(["webp bytes"], "screenshot", { type: "image/webp" });
    const text = new File(["https://example.test/image.png"], "link.txt", { type: "text/plain" });
    const result = clipboardImageFiles(clipboard([item(null), { kind: "string", type: "text/plain", getAsFile: () => null }], [text, webp]));

    expect(result.map((file) => file.name)).toEqual(["screenshot.webp"]);
  });

  it("ignores text, HTML, URLs, null files and non-image files", () => {
    const text = new File(["image URL"], "photo.png", { type: "text/plain" });
    expect(clipboardImageFiles(clipboard([
      { kind: "string", type: "text/html", getAsFile: () => null },
      { kind: "string", type: "text/uri-list", getAsFile: () => null },
      item(null),
      item(text)
    ], [text]))).toEqual([]);
    expect(clipboardImageFiles(null)).toEqual([]);
  });

  it("normalizes generic screenshot names but keeps usable names and image bytes", async () => {
    const original = new File([Uint8Array.from([1, 2, 3, 4])], "capture.image", { type: "image/gif" });
    const good = new File(["jpeg"], "holiday.jpg", { type: "image/jpeg" });
    const [renamed, preserved] = clipboardImageFiles(clipboard([item(original), item(good)]));

    expect(renamed.name).toBe("capture.gif");
    expect(new Uint8Array(await renamed.arrayBuffer())).toEqual(Uint8Array.from([1, 2, 3, 4]));
    expect(preserved).toBe(good);
  });

  it("fills a missing File MIME from the image clipboard item even when its filename is usable", async () => {
    const original = new File([Uint8Array.from([7, 8, 9])], "screenshot.png");
    const [file] = clipboardImageFiles(clipboard([item(original, "image/png")]));

    expect(file.name).toBe("screenshot.png");
    expect(file.type).toBe("image/png");
    expect(new Uint8Array(await file.arrayBuffer())).toEqual(Uint8Array.from([7, 8, 9]));
  });
});

describe("insertClipboardImageReferences", () => {
  it("replaces a selected range when the prompt has not changed", () => {
    expect(insertClipboardImageReferences("请修改这里的衣服", ["@图片1"], {
      text: "请修改这里的衣服", start: 3, end: 5
    })).toBe("请修改 @图片1 的衣服");
    expect(insertClipboardImageReferences("请修改  衣服", ["图片2"], {
      text: "请修改  衣服", start: 4, end: 5
    })).toBe("请修改 @图片2 衣服");
  });

  it("appends to the latest prompt when the user edited it during upload", () => {
    expect(insertClipboardImageReferences("原提示词又加了内容", ["@图片3"], {
      text: "原提示词", start: 0, end: 4
    })).toBe("原提示词又加了内容 @图片3");
  });

  it("deduplicates exact references without confusing image 1 and image 10", () => {
    expect(insertClipboardImageReferences("看 @图片10", ["@图片1", "@图片1", "@图片10"]))
      .toBe("看 @图片10 @图片1");
    expect(insertClipboardImageReferences("看 @图片1", ["@图片1"]))
      .toBe("看 @图片1");
  });

  it("does not erase selection text if all requested references already exist", () => {
    expect(insertClipboardImageReferences("替换这里 @图片1", ["@图片1"], {
      text: "替换这里 @图片1", start: 2, end: 4
    })).toBe("替换这里 @图片1");
  });
});

describe("clipboardImageURL", () => {
  const asClipboard = (plain: string, html = "") => ({
    getData: (type: string) => type === "text/plain" ? plain : html
  }) as Pick<DataTransfer, "getData">;

  it("preserves a single signed URL exactly after trimming, regardless of suffix", () => {
    const signed = "https://images.example.test/asset.image?Expires=123&Signature=A%2FB%3D&key=abc";
    expect(clipboardImageURL(asClipboard(`  ${signed}  `))).toBe(signed);
    expect(clipboardImageURL(asClipboard("http://images.example.test/opaque?id=1")))
      .toBe("http://images.example.test/opaque?id=1");
  });

  it("does not extract URLs from prose or accept more than one URL", () => {
    expect(clipboardImageURL(asClipboard("请看 https://images.example.test/a.png"))).toBeNull();
    expect(clipboardImageURL(asClipboard("https://images.example.test/a.png\nhttps://images.example.test/b.png"))).toBeNull();
    expect(clipboardImageURL(asClipboard("https://images.example.test/a.png more"))).toBeNull();
  });

  it("ignores HTML and rejects non-HTTP schemes and userinfo", () => {
    expect(clipboardImageURL(asClipboard("", '<img src="https://images.example.test/a.png">'))).toBeNull();
    for (const value of [
      "data:image/png;base64,AAAA", "file:///tmp/a.png", "javascript:alert(1)",
      "https://user:pass@images.example.test/a.png", "https://@images.example.test/a.png",
      "images.example.test/a.png"
    ]) expect(clipboardImageURL(asClipboard(value))).toBeNull();
    expect(clipboardImageURL(null)).toBeNull();
  });

  it("rejects oversized URLs and embedded whitespace", () => {
    expect(clipboardImageURL(asClipboard(`https://images.example.test/${"a".repeat(8192)}`))).toBeNull();
    expect(clipboardImageURL(asClipboard("https://images.example.test/a\tb"))).toBeNull();
  });
});