import { describe, expect, it } from 'vitest';
import { buildCybersigil, GLYPHS } from './cybersigil';

/** Deterministic LCG so a given seed reproduces a given sigil. */
function seeded(seed: number): () => number {
  let s = seed >>> 0;
  return () => {
    s = (s * 1664525 + 1013904223) >>> 0;
    return s / 4294967296;
  };
}

describe('buildCybersigil', () => {
  it('is deterministic for a fixed RNG', () => {
    const a = buildCybersigil({ rng: seeded(42) });
    const b = buildCybersigil({ rng: seeded(42) });
    expect(a).toBe(b);
  });

  it('varies with the seed', () => {
    expect(buildCybersigil({ rng: seeded(1) })).not.toBe(buildCybersigil({ rng: seeded(2) }));
  });

  it('emits a single well-formed root svg', () => {
    const svg = buildCybersigil({ rng: seeded(7) });
    expect(svg.startsWith('<svg')).toBe(true);
    expect(svg.endsWith('</svg>')).toBe(true);
    expect(svg.match(/<svg/g)).toHaveLength(1);
    // no formatting holes leaked into the path data
    expect(svg).not.toMatch(/NaN|undefined|Infinity/);
  });

  it('is vertically mirrored (two halves, one flipped about x=0)', () => {
    const svg = buildCybersigil({ rng: seeded(7) });
    expect(svg.match(/class="cs-sig-half"/g)).toHaveLength(2);
    expect(svg).toContain('transform="scale(-1 1)"');
  });

  it('every stroke is pathLength-normalised for the carve animation', () => {
    const svg = buildCybersigil({ rng: seeded(99) });
    const paths = svg.match(/<path\b[^>]*>/g) ?? [];
    expect(paths.length).toBeGreaterThan(0);
    for (const p of paths) expect(p).toContain('pathLength="1"');
  });

  it('exposes a numeric, positive viewBox', () => {
    const svg = buildCybersigil({ rng: seeded(7) });
    const vb = svg.match(/viewBox="([^"]+)"/)?.[1] ?? '';
    const nums = vb.split(/\s+/).map(Number);
    expect(nums).toHaveLength(4);
    expect(nums.every(Number.isFinite)).toBe(true);
    expect(nums[2]).toBeGreaterThan(0); // width
    expect(nums[3]).toBeGreaterThan(0); // height
  });

  it('honours the count option and stays bounded', () => {
    const sparse = buildCybersigil({ count: 1, rng: seeded(5) });
    const dense = buildCybersigil({ count: 9, rng: seeded(5) });
    const n = (s: string) => (s.match(/<path/g) ?? []).length;
    expect(n(dense)).toBeGreaterThan(n(sparse));
    expect(n(dense)).toBeLessThanOrEqual(260); // MAX_PATHS(110) mirrored + ornaments
  });

  it('ships a non-empty glyph library with valid path data', () => {
    expect(GLYPHS.length).toBeGreaterThan(0);
    for (const g of GLYPHS) {
      expect(g.w).toBeGreaterThan(0);
      expect(g.h).toBeGreaterThan(0);
      expect(g.d).toMatch(/^M/);
    }
  });
});