import { flushPromises, mount } from "@vue/test-utils";
import { beforeEach, describe, expect, it, vi } from "vitest";

const getDocumentMock = vi.hoisted(() => vi.fn());
const renderMock = vi.hoisted(() => vi.fn());
const destroyMock = vi.hoisted(() => vi.fn());

vi.mock("pdfjs-dist", () => ({
  GlobalWorkerOptions: { workerSrc: "" },
  getDocument: getDocumentMock,
}));

import PdfViewer from "./PdfViewer.vue";

describe("PdfViewer", () => {
  beforeEach(() => {
    vi.clearAllMocks();
    renderMock.mockReturnValue({ promise: Promise.resolve(), cancel: vi.fn() });
    destroyMock.mockResolvedValue(undefined);
    getDocumentMock.mockReturnValue({
      promise: Promise.resolve({
        numPages: 2,
        getPage: vi.fn().mockResolvedValue({
          getViewport: ({ scale }: { scale: number }) => ({ width: 600 * scale, height: 800 * scale }),
          render: renderMock,
        }),
        destroy: destroyMock,
      }),
      destroy: destroyMock,
    });
  });

  it("renders PDF pages to canvas without an iframe", async () => {
    const wrapper = mount(PdfViewer, { props: { src: "blob:test-pdf" } });
    await flushPromises();

    expect(getDocumentMock).toHaveBeenCalledWith({ url: "blob:test-pdf" });
    expect(wrapper.findAll("canvas")).toHaveLength(2);
    expect(wrapper.find("iframe").exists()).toBe(false);
    expect(renderMock).toHaveBeenCalled();
    expect(wrapper.text()).toContain("/ 2");

    await wrapper.get("button:nth-of-type(2)").trigger("click");
    await flushPromises();
    expect(wrapper.text()).toContain("/ 2");

    wrapper.unmount();
    await flushPromises();
    expect(destroyMock).toHaveBeenCalled();
  });

  it("integrates the dialog close action into the viewer toolbar", async () => {
    const wrapper = mount(PdfViewer, { props: { src: "blob:test-pdf", showClose: true } });
    await flushPromises();

    await wrapper.get('[aria-label="关闭预览"]').trigger("click");

    expect(wrapper.emitted("close")).toHaveLength(1);
  });

  it("keeps the visible document center anchored while zooming", async () => {
    const wrapper = mount(PdfViewer, { props: { src: "blob:test-pdf" } });
    await flushPromises();
    const viewport = wrapper.get(".pdf-viewer__viewport").element as HTMLElement;
    Object.defineProperties(viewport, {
      clientWidth: { configurable: true, value: 800 },
      clientHeight: { configurable: true, value: 600 },
      scrollWidth: {
        configurable: true,
        get: () => Math.max(800, Number.parseInt(wrapper.get("canvas").element.style.width, 10) || 0),
      },
      scrollHeight: {
        configurable: true,
        get: () => Math.max(600, Number.parseInt(wrapper.get("canvas").element.style.height, 10) || 0),
      },
    });
    await wrapper.get("button.is-active").trigger("click");
    await flushPromises();

    await wrapper.get('[aria-label="放大"]').trigger("click");
    await flushPromises();

    expect(viewport.scrollLeft).toBeGreaterThan(0);
    expect(viewport.scrollTop).toBeGreaterThan(0);
  });

  it("shows the original filename in the center of the toolbar", async () => {
    const wrapper = mount(PdfViewer, {
      props: { src: "blob:test-pdf", filename: "研究方案最终版.pdf" },
    });
    await flushPromises();

    expect(wrapper.get(".pdf-viewer__filename").text()).toBe("研究方案最终版.pdf");
    expect(wrapper.text()).not.toContain("页文档");
  });

  it("updates the current page while scrolling through the continuous document", async () => {
    const wrapper = mount(PdfViewer, { props: { src: "blob:test-pdf" } });
    await flushPromises();
    const viewport = wrapper.get(".pdf-viewer__viewport");
    const pages = wrapper.findAll(".pdf-viewer__page");
    Object.defineProperties(viewport.element, {
      clientHeight: { configurable: true, value: 600 },
      scrollTop: { configurable: true, writable: true, value: 850 },
    });
    Object.defineProperties(pages[0].element, {
      offsetTop: { configurable: true, value: 0 },
      offsetHeight: { configurable: true, value: 800 },
    });
    Object.defineProperties(pages[1].element, {
      offsetTop: { configurable: true, value: 816 },
      offsetHeight: { configurable: true, value: 800 },
    });

    await viewport.trigger("scroll");

    expect((wrapper.get(".pdf-viewer__page-input").element as HTMLInputElement).value).toBe("2");
  });
});