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

import {
  buildMessageWithAttachments,
  type ChatAttachment,
} from "./chat-attachments.js";

const PNG_1x1 =
  "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mP8/woAAn8B9FD5fHAAAAAASUVORK5CYII=";

describe("buildMessageWithAttachments", () => {
  it("embeds a single image as data URL", () => {
    const msg = buildMessageWithAttachments("see this", [
      {
        type: "image",
        mimeType: "image/png",
        fileName: "dot.png",
        content: PNG_1x1,
      },
    ]);
    expect(msg).toContain("see this");
    expect(msg).toContain(`data:image/png;base64,${PNG_1x1}`);
    expect(msg).toContain("![dot.png]");
  });

  it("rejects non-image mime types", () => {
    const bad: ChatAttachment = {
      type: "file",
      mimeType: "application/pdf",
      fileName: "a.pdf",
      content: "AAA",
    };
    expect(() => buildMessageWithAttachments("x", [bad])).toThrow(/image/);
  });

  it("rejects invalid base64 content", () => {
    const bad: ChatAttachment = {
      type: "image",
      mimeType: "image/png",
      fileName: "dot.png",
      content: "%not-base64%",
    };
    expect(() => buildMessageWithAttachments("x", [bad])).toThrow(/base64/);
  });

  it("rejects images over limit", () => {
    const big = Buffer.alloc(6_000_000, 0).toString("base64");
    const att: ChatAttachment = {
      type: "image",
      mimeType: "image/png",
      fileName: "big.png",
      content: big,
    };
    expect(() =>
      buildMessageWithAttachments("x", [att], { maxBytes: 5_000_000 }),
    ).toThrow(/exceeds size limit/i);
  });
});