import { readFileSync } from 'node:fs';
import { renderToStaticMarkup } from 'react-dom/server';
import { describe, expect, it } from 'vitest';
import { DonutMetricCard } from '../../src/components/DonutMetricCard/DonutMetricCard';
import { donutArcPath } from '../../src/components/DonutMetricCard/donut-arc';

// Line endings depend on the checkout (CRLF on Windows working copies); the contract is about content.
const readStyle = (file: string) => readFileSync(new URL(`../../src/styles/${file}`, import.meta.url), 'utf8').replace(/\r\n/g, '\n');
const styles = readStyle('components.css');
const tileContract = readStyle('tile-contract.css');
const tokens = readStyle('ui-tokens.css');

describe('DonutMetricCard binding design contract', () => {
  it('renders the shared full-circle reference with a bold count above a regular percentage', () => {
    const html = renderToStaticMarkup(
      <DonutMetricCard label="Deviation" value={453} percentage={51} tone="deviation" />
    );

    expect(html).toContain('class="donut-metric-card donut-metric-card--deviation"');
    expect(html).toMatch(/<h3 class="donut-metric-card__title">Deviation<\/h3><div class="donut-metric-card__plot">/);
    expect(html).toContain('class="donut-metric-card__track" cx="60" cy="60" r="48" pathLength="100"');
    expect(html).toContain('class="donut-metric-card__progress" d="M 114 60 A 54 54 0 1 1');
    expect(html).toContain('<div class="donut-metric-card__primary"><strong>453</strong></div>');
    expect(html).toContain('<small>51%</small>');
    expect(styles).toContain('.donut-metric-card__progress {\n  fill: currentColor;');
    expect(styles).toContain('transform: rotate(-90deg);');
    expect(styles).toMatch(/\.donut-metric-card__values\s*\{[^}]*inset:\s*calc\(var\(--donut-ring-stroke\) \+ var\(--space-2\)\);/s);
    expect(styles).not.toContain('filter: var(--donut-ring-shadow);');
    expect(styles).toMatch(/\.donut-metric-card__primary strong\s*\{[^}]*font-weight:\s*var\(--fw-bold\);/s);
    expect(styles).toMatch(/\.donut-metric-card__values > small\s*\{[^}]*font-weight:\s*var\(--fw-regular\);/s);
    expect(styles).not.toContain('stroke-linecap: round;');
    expect(styles).toContain('@keyframes donut-progress-build');
    expect(styles).not.toContain('.donut-metric-card::before');
    expect(styles).not.toContain('@keyframes donut-accent-build');
    expect(styles).toContain('animation: donut-progress-build var(--dur-data-build) var(--ease-data-build) both;');
    expect(styles).toMatch(/\.donut-metric-rack\s*\{[^}]*grid-template-columns:\s*repeat\(auto-fill, var\(--tile-compact-width\)\);[^}]*justify-content:\s*start;/s);
    expect(tileContract).toMatch(/\.donut-metric-rack\s*\{[^}]*grid-template-columns:\s*repeat\(auto-fill, var\(--tile-compact-width\)\);[^}]*justify-content:\s*start;/s);
    expect(tokens).toContain('--dur-data-build: 700ms;');
    expect(tokens).toContain('--donut-value-size: 26px;');
    expect(tokens).not.toContain('--donut-ring-shadow:');
    expect(tokens).toContain('--donut-percent-size: 14px;');
    expect(tokens).toContain('--donut-compact-value-size: 22px;');
    expect(tokens).toContain('--donut-compact-percent-size: 12px;');
    expect(styles).not.toContain('.sidebar-severity-card');
  });

  it('renders an empty progress arc at zero and clamps percentages', () => {
    const zero = renderToStaticMarkup(
      <DonutMetricCard label="Error" value={2} percentage={0} tone="error" />
    );
    const clamped = renderToStaticMarkup(
      <DonutMetricCard label="Results All" value={885} percentage={120} tone="all" />
    );

    expect(zero).not.toContain('donut-metric-card__progress');
    expect(zero).toContain('<strong>2</strong>');
    expect(zero).toContain('<small>0%</small>');
    expect(clamped).toContain(`d="${donutArcPath(100)}"`);
    expect(clamped).toContain('<strong>885</strong>');
    expect(clamped).toContain('<small>100%</small>');
    expect(zero).not.toContain('<animate');
    expect(zero).not.toContain('donut-small-arc-marker');
  });

  it('keeps a tiny positive arc proportional and marks it legibly at compact sizes', () => {
    const tiny = renderToStaticMarkup(
      <DonutMetricCard label="Not Applicable" value={4} percentage={4 / 1833 * 100} tone="not-applicable" />
    );
    const onePercent = renderToStaticMarkup(
      <DonutMetricCard label="Not Applicable" value={4} percentage={1} tone="not-applicable" />
    );
    expect(tiny).toContain(`d="${donutArcPath(4 / 1833 * 100)}"`);
    expect(tiny).toContain('donut-small-arc-marker');
    expect(tiny).toMatch(/class="donut-small-arc-marker" x="102" y="60"/);
    expect(tiny).toContain('<small>&lt;1%</small>');
    expect(onePercent).toContain(`d="${donutArcPath(1)}"`);
    expect(onePercent).toContain('donut-small-arc-marker');
    expect(onePercent).toContain('<small>1%</small>');
  });

  it('draws flat radial ends at 12 o’clock for small arcs and exact adjacent boundaries for segments', () => {
    const tenPercent = donutArcPath(10);
    expect(tenPercent).toMatch(/^M 114 60 A 54 54 0 0 1 /);
    expect(tenPercent).toMatch(/A 42 42 0 0 0 102 60 Z$/);
    expect(donutArcPath(0)).toBe('');
    expect(donutArcPath(25, 10)).toContain('A 54 54 0 0 1');
    expect(donutArcPath(100)).toContain('A 54 54 0 0 1 6 60');
  });

  it('distinguishes a pending metric from an observed zero', () => {
    const pending = renderToStaticMarkup(
      <DonutMetricCard label="Deviation" value={null} percentage={0} tone="deviation" pendingLabel="Loading…" />
    );
    expect(pending).toContain('aria-label="Deviation: Loading…"');
    expect(pending).toContain('<strong>—</strong>');
    expect(pending).toContain('<small>Loading…</small>');
    expect(pending).not.toContain('donut-metric-card__progress');
    expect(pending).not.toContain('<small>0%</small>');
  });

  it('supports a single suffixed score without a duplicate percentage label', () => {
    const html = renderToStaticMarkup(
      <DonutMetricCard label="Compliance Score" value={36} valueSuffix="%" showPercentage={false} percentage={36} tone="all" />
    );

    expect(html).toContain('<strong>36%</strong>');
    expect(html).not.toContain('<small>36%</small>');
  });

  it('becomes an accessible active filter control when clickable', () => {
    const html = renderToStaticMarkup(
      <DonutMetricCard
        label="High"
        value={12}
        percentage={24}
        tone="high"
        active
        onClick={() => undefined}
        className="test-donut-card"
      />
    );

    expect(html).toContain('type="button"');
    expect(html).toContain('aria-pressed="true"');
    expect(html).toContain('donut-metric-card--high test-donut-card');
  });
});