import { Readable } from "stream";

import { StampSettingsService } from "./stamp-settings.service";

/**
 * The one global company stamp feeds three document paths (invoices, warehouse
 * papers, contract signature blocks). All three treat the returned value as a
 * `data:` URL — so the data-URL-or-null contract of getStampImageUrl is what
 * these specs pin down, especially its behaviour when MinIO cannot be reached.
 */
describe("StampSettingsService.getStampImageUrl", () => {
  const PNG = Buffer.from("fake-png-bytes");
  const OBJECT_URL = "https://minio.local:9000/edr-freight/stamp/company.png";

  const build = (
    overrides: {
      stampUrl?: string | null;
      getFileStream?: jest.Mock;
      findSingleton?: jest.Mock;
    } = {},
  ) => {
    const service = Object.create(
      StampSettingsService.prototype,
    ) as StampSettingsService;
    const warn = jest.fn();
    Object.assign(service, {
      logger: { warn, log: jest.fn() },
      repository: {
        findSingleton:
          overrides.findSingleton ??
          jest.fn().mockResolvedValue({
            id: "s-1",
            stampFileId: overrides.stampUrl ? "f-1" : null,
            stampFile: overrides.stampUrl ? { url: overrides.stampUrl } : null,
            updatedById: null,
            updatedAt: null,
          }),
        create: jest.fn(),
        update: jest.fn(),
      },
      minioService: {
        getObjectNameFromUrl: jest.fn().mockReturnValue("stamp/company.png"),
        getFileStream:
          overrides.getFileStream ??
          jest.fn().mockResolvedValue(Readable.from(PNG)),
      },
      filesService: { upload: jest.fn() },
    });
    return { service, warn };
  };

  it("inlines the stored stamp as a data URL", async () => {
    const { service } = build({ stampUrl: OBJECT_URL });

    await expect(service.getStampImageUrl()).resolves.toBe(
      `data:image/png;base64,${PNG.toString("base64")}`,
    );
  });

  it("returns null when no stamp is configured", async () => {
    const { service } = build({ stampUrl: null });

    await expect(service.getStampImageUrl()).resolves.toBeNull();
  });

  it("passes an already-inlined data URL straight through", async () => {
    const dataUrl = "data:image/png;base64,QUJD";
    const { service } = build({ stampUrl: dataUrl });

    await expect(service.getStampImageUrl()).resolves.toBe(dataUrl);
  });

  /**
   * Regression: inlineImageUrl falls back to the raw object URL when MinIO is
   * unreachable, which is right for getView (a browser can fetch it) but wrong
   * here. ContractTransitionService base64-decodes this value to snapshot the
   * seal — and a URL decodes to garbage bytes WITHOUT throwing, so a transient
   * MinIO failure used to seal an executed contract with a corrupt image file.
   * Degrade to null instead so callers draw their text/vector seal.
   */
  it("returns null rather than a raw object URL when MinIO inlining fails", async () => {
    const { service, warn } = build({
      stampUrl: OBJECT_URL,
      getFileStream: jest.fn().mockRejectedValue(new Error("connect ECONNREFUSED")),
    });

    await expect(service.getStampImageUrl()).resolves.toBeNull();
    expect(warn).toHaveBeenCalledWith(expect.stringMatching(/plain seal/i));
  });

  it("never throws when the settings lookup itself fails", async () => {
    const { service, warn } = build({
      findSingleton: jest.fn().mockRejectedValue(new Error("db is down")),
    });

    await expect(service.getStampImageUrl()).resolves.toBeNull();
    expect(warn).toHaveBeenCalledWith(expect.stringContaining("db is down"));
  });

  it("still exposes the raw URL through getView, which a browser can load", async () => {
    const { service } = build({
      stampUrl: OBJECT_URL,
      getFileStream: jest.fn().mockRejectedValue(new Error("connect ECONNREFUSED")),
    });

    await expect(service.getView()).resolves.toEqual(
      expect.objectContaining({ stampImageUrl: OBJECT_URL }),
    );
  });
});