// @vitest-environment happy-dom

import { describe, expect, it } from "vitest";
import { constrainSemanticCoversToPage } from "../src/semantic-cover-fit.js";

function createCover(height: number) {
  const root = document.createElement("div");
  root.innerHTML = `
    <header
      data-semantic-region="cover"
      data-semantic-break-after="next-page"
    >封面</header>
  `;
  const cover = root.querySelector<HTMLElement>("header")!;
  cover.getBoundingClientRect = () =>
    ({ height } as DOMRect);
  return { root, cover };
}

describe("语义封面页面适配", () => {
  it("只将超过横向页面内容区的封面收束为单页高度", () => {
    const { root, cover } = createCover(900);

    expect(constrainSemanticCoversToPage(root, 680)).toBe(1);
    expect(cover.style.boxSizing).toBe("border-box");
    expect(cover.style.height).toBe("680px");
    expect(cover.style.minHeight).toBe("680px");
    expect(cover.style.maxHeight).toBe("680px");
    expect(cover.dataset.semanticCoverFit).toBe("constrained");
  });

  it("纵向页面可以容纳主题封面时保持主题原始高度", () => {
    const { root, cover } = createCover(680);

    expect(constrainSemanticCoversToPage(root, 900)).toBe(0);
    expect(cover.getAttribute("style")).toBeNull();
    expect(cover.dataset.semanticCoverFit).toBeUndefined();
  });
});