import { describe, it, expect, beforeEach, vi } from 'vitest';
import { DataBuffer } from '@/services/ble/DataBuffer';
import type { NormalizedReading } from '@/services/ble/types';

// Mock Taro Storage
const storage = new Map<string, string>();
vi.mock('@tarojs/taro', () => ({
  default: {
    getStorageSync: vi.fn((key: string) => storage.get(key) || ''),
    setStorageSync: vi.fn((key: string, value: string) => { storage.set(key, value); }),
    removeStorageSync: vi.fn((key: string) => { storage.delete(key); }),
    getStorageInfoSync: vi.fn(() => ({ keys: Array.from(storage.keys()), limitSize: 10240, currentSize: storage.size })),
  },
}));

function makeReading(overrides: Partial<NormalizedReading> = {}): NormalizedReading {
  return {
    device_type: 'heart_rate',
    values: { heart_rate: 72 },
    measured_at: new Date().toISOString(),
    ...overrides,
  };
}

describe('DataBuffer', () => {
  let buffer: DataBuffer;

  beforeEach(() => {
    storage.clear();
    buffer = new DataBuffer({ bucketSize: 100 });
  });

  it('push 添加读数并持久化', () => {
    const reading = makeReading();
    buffer.push(reading);
    expect(buffer.size()).toBe(1);
  });

  it('push 批量添加读数', () => {
    const readings = Array.from({ length: 10 }, (_, i) =>
      makeReading({ measured_at: new Date(Date.now() + i * 1000).toISOString() }),
    );
    buffer.push(readings);
    expect(buffer.size()).toBe(10);
  });

  it('flush 返回并清空缓冲区', () => {
    buffer.push([
      makeReading({ measured_at: '2026-05-04T10:00:00.000Z' }),
      makeReading({ measured_at: '2026-05-04T10:00:01.000Z' }),
    ]);
    const flushed = buffer.flush();
    expect(flushed.length).toBe(2);
    expect(buffer.size()).toBe(0);
  });

  it('超过 maxTotal 时丢弃最旧数据', () => {
    const smallBuffer = new DataBuffer({ bucketSize: 5, maxTotal: 10 });
    for (let i = 0; i < 15; i++) {
      smallBuffer.push(makeReading({ measured_at: new Date(i * 1000).toISOString() }));
    }
    expect(smallBuffer.size()).toBe(10);
  });

  it('去重：相同 measured_at + device_type 不重复存储', () => {
    const ts = '2026-05-04T10:00:00.000Z';
    buffer.push(makeReading({ measured_at: ts }));
    buffer.push(makeReading({ measured_at: ts }));
    expect(buffer.size()).toBe(1);
  });

  it('restore 从 Storage 恢复未上传数据', () => {
    buffer.push([
      makeReading({ measured_at: '2026-05-04T10:00:00.000Z' }),
      makeReading({ measured_at: '2026-05-04T10:00:01.000Z' }),
    ]);
    // 模拟重启：新建 DataBuffer 并 restore
    const restored = new DataBuffer({ bucketSize: 100 });
    const count = restored.restore();
    expect(count).toBe(2);
    expect(restored.size()).toBe(2);
  });

  it('clear 清空缓冲区和 Storage', () => {
    buffer.push(makeReading());
    buffer.clear();
    expect(buffer.size()).toBe(0);
  });
});