import { beforeEach, describe, expect, it, mock, type Mock } from 'bun:test';
import type { Logger } from '@stock-bot/logger';
import { processBatchJob, processItems } from '../src/batch-processor';
import type { BatchJobData, ProcessOptions, Queue, QueueManager } from '../src/types';

describe('Batch Processor', () => {
  type MockLogger = {
    info: Mock<(message: string, meta?: any) => void>;
    error: Mock<(message: string, meta?: any) => void>;
    warn: Mock<(message: string, meta?: any) => void>;
    debug: Mock<(message: string, meta?: any) => void>;
    trace: Mock<(message: string, meta?: any) => void>;
  };

  type MockQueue = {
    add: Mock<(name: string, data: any, options?: any) => Promise<{ id: string }>>;
    addBulk: Mock<
      (jobs: Array<{ name: string; data: any; opts?: any }>) => Promise<Array<{ id: string }>>
    >;
    createChildLogger: Mock<(component: string, meta?: any) => MockLogger>;
    getName: Mock<() => string>;
  };

  type MockQueueManager = {
    getQueue: Mock<(name: string) => MockQueue>;
    getCache: Mock<
      (name: string) => {
        get: Mock<(key: string) => Promise<any>>;
        set: Mock<(key: string, value: any, ttl?: number) => Promise<void>>;
        del: Mock<(key: string) => Promise<void>>;
      }
    >;
  };

  let mockLogger: MockLogger;
  let mockQueue: MockQueue;
  let mockQueueManager: MockQueueManager;
  let mockCache: {
    get: Mock<(key: string) => Promise<any>>;
    set: Mock<(key: string, value: any, ttl?: number) => Promise<void>>;
    del: Mock<(key: string) => Promise<void>>;
  };

  beforeEach(() => {
    mockLogger = {
      info: mock(() => {}),
      error: mock(() => {}),
      warn: mock(() => {}),
      debug: mock(() => {}),
      trace: mock(() => {}),
    };

    mockQueue = {
      add: mock(async () => ({ id: 'job-123' })),
      addBulk: mock(async jobs => jobs.map((_, i) => ({ id: `job-${i + 1}` }))),
      createChildLogger: mock(() => mockLogger),
      getName: mock(() => 'test-queue'),
    };

    mockCache = {
      get: mock(async () => null),
      set: mock(async () => {}),
      del: mock(async () => {}),
    };

    mockQueueManager = {
      getQueue: mock(() => mockQueue),
      getCache: mock(() => mockCache),
    };
  });

  describe('processBatchJob', () => {
    it('should process all items successfully', async () => {
      const batchData: BatchJobData = {
        payloadKey: 'test-payload-key',
        batchIndex: 0,
        totalBatches: 1,
        itemCount: 3,
        totalDelayHours: 0,
      };

      // Mock the cached payload
      const cachedPayload = {
        items: ['item1', 'item2', 'item3'],
        options: {
          batchSize: 2,
          concurrency: 1,
        },
      };
      mockCache.get.mockImplementation(async () => cachedPayload);

      const result = await processBatchJob(
        batchData,
        'test-queue',
        mockQueueManager as unknown as QueueManager
      );

      expect(mockCache.get).toHaveBeenCalledWith('test-payload-key');
      expect(mockQueue.addBulk).toHaveBeenCalled();
      expect(result).toBeDefined();
    });

    it('should handle partial failures', async () => {
      const batchData: BatchJobData = {
        payloadKey: 'test-payload-key',
        batchIndex: 0,
        totalBatches: 1,
        itemCount: 3,
        totalDelayHours: 0,
      };

      // Mock the cached payload
      const cachedPayload = {
        items: ['item1', 'item2', 'item3'],
        options: {},
      };
      mockCache.get.mockImplementation(async () => cachedPayload);

      // Make addBulk throw an error to simulate failure
      mockQueue.addBulk.mockImplementation(async () => {
        throw new Error('Failed to add jobs');
      });

      // processBatchJob should still complete even if addBulk fails
      const result = await processBatchJob(
        batchData,
        'test-queue',
        mockQueueManager as unknown as QueueManager
      );

      expect(mockQueue.addBulk).toHaveBeenCalled();
      // The error is logged in addJobsInChunks, not in processBatchJob
      expect(mockLogger.error).toHaveBeenCalledWith('Failed to add job chunk', expect.any(Object));
    });

    it('should handle empty items', async () => {
      const batchData: BatchJobData = {
        payloadKey: 'test-payload-key',
        batchIndex: 0,
        totalBatches: 1,
        itemCount: 0,
        totalDelayHours: 0,
      };

      // Mock the cached payload with empty items
      const cachedPayload = {
        items: [],
        options: {},
      };
      mockCache.get.mockImplementation(async () => cachedPayload);

      const result = await processBatchJob(
        batchData,
        'test-queue',
        mockQueueManager as unknown as QueueManager
      );

      expect(mockQueue.addBulk).not.toHaveBeenCalled();
      expect(result).toBeDefined();
    });

    it('should track duration', async () => {
      const batchData: BatchJobData = {
        payloadKey: 'test-payload-key',
        batchIndex: 0,
        totalBatches: 1,
        itemCount: 1,
        totalDelayHours: 0,
      };

      // Mock the cached payload
      const cachedPayload = {
        items: ['item1'],
        options: {},
      };
      mockCache.get.mockImplementation(async () => cachedPayload);

      // Add delay to queue.add
      mockQueue.add.mockImplementation(
        () => new Promise(resolve => setTimeout(() => resolve({ id: 'job-1' }), 10))
      );

      const result = await processBatchJob(
        batchData,
        'test-queue',
        mockQueueManager as unknown as QueueManager
      );

      expect(result).toBeDefined();
      // The function doesn't return duration in its result
    });
  });

  describe('processItems', () => {
    it('should process items with default options', async () => {
      const items = [1, 2, 3, 4, 5];
      const options: ProcessOptions = { totalDelayHours: 0 };

      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.totalItems).toBe(5);
      expect(result.jobsCreated).toBe(5);
      expect(result.mode).toBe('direct');
      expect(mockQueue.addBulk).toHaveBeenCalled();
    });

    it('should process items in batches', async () => {
      const items = [1, 2, 3, 4, 5];
      const options: ProcessOptions = {
        totalDelayHours: 0,
        useBatching: true,
        batchSize: 2,
      };

      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.totalItems).toBe(5);
      expect(result.mode).toBe('batch');
      // When batching is enabled, it creates batch jobs instead of individual jobs
      expect(mockQueue.addBulk).toHaveBeenCalled();
    });

    it('should handle concurrent processing', async () => {
      const items = [1, 2, 3, 4];
      const options: ProcessOptions = {
        totalDelayHours: 0,
      };

      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.totalItems).toBe(4);
      expect(result.jobsCreated).toBe(4);
      expect(mockQueue.addBulk).toHaveBeenCalled();
    });

    it('should handle empty array', async () => {
      const items: number[] = [];
      const options: ProcessOptions = { totalDelayHours: 0 };

      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.totalItems).toBe(0);
      expect(result.jobsCreated).toBe(0);
      expect(result.mode).toBe('direct');
      expect(mockQueue.addBulk).not.toHaveBeenCalled();
    });

    it('should propagate errors', async () => {
      const items = [1, 2, 3];
      const options: ProcessOptions = { totalDelayHours: 0 };

      // Make queue.addBulk throw an error
      mockQueue.addBulk.mockImplementation(async () => {
        throw new Error('Process error');
      });

      // processItems catches errors and continues, so it won't reject
      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.jobsCreated).toBe(0);
      expect(mockQueue.addBulk).toHaveBeenCalled();
      expect(mockLogger.error).toHaveBeenCalledWith('Failed to add job chunk', expect.any(Object));
    });

    it('should process large batches efficiently', async () => {
      const items = Array.from({ length: 100 }, (_, i) => i);
      const options: ProcessOptions = {
        totalDelayHours: 0,
        useBatching: true,
        batchSize: 20,
      };

      const result = await processItems(
        items,
        'test-queue',
        options,
        mockQueueManager as unknown as QueueManager
      );

      expect(result.totalItems).toBe(100);
      expect(result.mode).toBe('batch');
      // With batching enabled and batch size 20, we should have 5 batch jobs
      expect(mockQueue.addBulk).toHaveBeenCalled();
    });
  });
});