import { mkdir, mkdtemp } from 'node:fs/promises';
import path from 'node:path';
import { createHash } from 'node:crypto';
import { SetStore, type ImagePipeline } from '../../src/storage/sets.ts';

export const SECTIONS = ['bar', 'food'] as const;

/** Deterministic stand-in for sharp, so storage tests need no image work. */
export class FakePipeline implements ImagePipeline {
  calls = 0;

  async process(data: Buffer, _originalName: string) {
    this.calls += 1;
    const hash = createHash('sha256').update(data).digest('hex').slice(0, 8);
    return {
      sourceExt: 'jpg' as const,
      hash,
      width: 3000,
      height: 2000,
      original: data,
      webp: Buffer.from(`webp:${hash}`),
      jpeg: Buffer.from(`jpeg:${hash}`),
      thumb: Buffer.from(`thumb:${hash}`),
    };
  }
}

export function testClock(start = '2026-01-01T00:00:00.000Z') {
  let time = Date.parse(start);
  return {
    now: () => new Date(time),
    advance: (ms: number) => {
      time += ms;
    },
    set: (iso: string) => {
      time = Date.parse(iso);
    },
  };
}

export async function tempDir(prefix: string): Promise<string> {
  const base = path.join(process.cwd(), '.tmp');
  await mkdir(base, { recursive: true });
  return mkdtemp(path.join(base, `${prefix}-`));
}

export function makeStore(
  dataDir: string,
  options: { clock?: ReturnType<typeof testClock>; maxPagesPerSet?: number } = {},
) {
  const pipeline = new FakePipeline();
  const clock = options.clock ?? testClock();
  const store = new SetStore({
    dataDir,
    pipeline,
    sections: [...SECTIONS],
    maxPagesPerSet: options.maxPagesPerSet ?? 40,
    timeZone: 'Asia/Kolkata',
    now: clock.now,
  });
  return { store, pipeline, clock };
}

export function pngBytes(label: string): Buffer {
  return Buffer.from(`fake-image:${label}`);
}