import { defaultExportConfig } from "@md-to-pdf/core";
import { describe, expect, it } from "vitest";
import {
  buildPagedMediaCss,
  createPagedPreviewRenderRequest,
  documentGeometryCss,
  formatPageNumber,
  isPagedPreviewFrameMessage,
  isPagedPreviewRenderRequest,
  PAGED_PREVIEW_MESSAGE_SCOPE,
  type PagedPreviewPayload
} from "../src/paged-preview";

const payload: PagedPreviewPayload = {
  articleHtml: '<article id="write"><h1>分页测试</h1></article>',
  fileName: "分页测试.md",
  metadata: {
    title: "分页测试",
    author: "",
    subject: "",
    keywords: [],
    language: "zh-CN"
  },
  features: [],
  themeCss: "#write { color: #333; }",
  exportConfig: defaultExportConfig
};

describe("分页预览协议", () => {
  it("生成真实纸张尺寸和页边距 CSS", () => {
    const css = buildPagedMediaCss(defaultExportConfig, payload);

    expect(css).toContain("size: 210mm 297mm");
    expect(css).toContain("margin: 16mm 16mm");
    expect(css).toContain("@bottom-center");
    expect(css).not.toContain("counter-reset: page");
    expect(css).toContain("#write thead");
    expect(css).toContain("display: table-header-group");
    expect(css).toContain("break-inside: avoid");
    expect(css).toContain(".pagedjs_pages");
    expect(css).toContain("padding: 34px 0");
    expect(css).toContain('html[data-render-target="preview"]');
    expect(css).toContain("overflow-x: hidden");
    expect(css).toContain("overflow-y: scroll");
    expect(css).toContain('html[data-render-target="pdf"]');
    expect(css).toContain("height: auto !important");
    expect(css).toContain("overflow: visible !important");
    expect(css).toContain("padding: 0");
    expect(css).toContain("break-after: page");
    expect(css).not.toContain("@media print");
  });

  it("安全替换页眉变量并生成三栏页边距盒", () => {
    const css = buildPagedMediaCss(
      {
        ...defaultExportConfig,
        header: {
          ...defaultExportConfig.header,
          enabled: true,
          showDivider: true,
          left: {
            enabled: true,
            content: '${title} — ${filename} "测试"'
          },
          center: {
            enabled: true,
            content: "${author}"
          }
        }
      },
      {
        ...payload,
        metadata: {
          ...payload.metadata,
          author: "内网团队"
        }
      }
    );

    expect(css).toContain("@top-left");
    expect(css).toContain("@top-center");
    expect(css).toContain("@top-right");
    expect(css).toContain(
      'content: "分页测试 — 分页测试.md \\"测试\\""'
    );
    expect(css).toContain('content: "内网团队"');
    expect(css).toContain("border-bottom: 0.2mm solid currentColor");
  });

  it("支持自定义页码模板和起始页码", () => {
    const css = buildPagedMediaCss(
      {
        ...defaultExportConfig,
        footer: {
          ...defaultExportConfig.footer,
          format: "custom",
          template: "第 ${page} / ${pages} 页",
          alignment: "right",
          startFrom: 5
        }
      },
      payload
    );

    expect(css).toContain("@bottom-right");
    expect(
      formatPageNumber(
        {
          ...defaultExportConfig.footer,
          format: "custom",
          template: "第 ${page} / ${pages} 页",
          startFrom: 5
        },
        2,
        8
      )
    ).toBe("第 7 / 8 页");
  });

  it("逐页递增内置页码格式但保持真实总页数", () => {
    expect(
      formatPageNumber(defaultExportConfig.footer, 0, 5)
    ).toBe("1 / 5");
    expect(
      formatPageNumber(defaultExportConfig.footer, 1, 5)
    ).toBe("2 / 5");
    expect(
      formatPageNumber(
        {
          ...defaultExportConfig.footer,
          format: "chinese-page-total",
          startFrom: 5
        },
        3,
        5
      )
    ).toBe("第 8 页 / 共 5 页");
    expect(
      formatPageNumber(
        {
          ...defaultExportConfig.footer,
          format: "dash-page"
        },
        4,
        5
      )
    ).toBe("- 5 -");
  });

  it("在主题 CSS 之后强制分页画布保持透明", () => {
    expect(documentGeometryCss).toContain(
      "background: transparent !important"
    );
  });

  it("生成并识别分页渲染请求", () => {
    const request = createPagedPreviewRenderRequest(7, payload);

    expect(request).toEqual({
      scope: PAGED_PREVIEW_MESSAGE_SCOPE,
      type: "render",
      requestId: 7,
      payload
    });
    expect(isPagedPreviewRenderRequest(request)).toBe(true);
    expect(
      isPagedPreviewRenderRequest({
        ...request,
        requestId: "7"
      })
    ).toBe(false);
  });

  it("只接受分页 iframe 协议消息", () => {
    expect(
      isPagedPreviewFrameMessage({
        scope: PAGED_PREVIEW_MESSAGE_SCOPE,
        type: "rendered",
        requestId: 3,
        pageCount: 2,
        contentHeight: 2300,
        mermaidErrors: []
      })
    ).toBe(true);
    expect(
      isPagedPreviewFrameMessage({
        scope: "other",
        type: "ready"
      })
    ).toBe(false);
  });
});