import { describe, test, expect, beforeEach, afterEach, spyOn } from 'bun:test'

describe('Fetch Mocking Verification', () => {
  let spyFetch: ReturnType<typeof spyOn>

  beforeEach(() => {
    // Mock global fetch
    spyFetch = spyOn(globalThis, 'fetch')
  })

  afterEach(() => {
    // Reset the spy after each test
    spyFetch.mockRestore()
  })

  test('should mock fetch with simple response', async () => {
    const mockResponse = { success: true, data: 'test' }

    spyFetch.mockImplementation(async () => {
      return new Response(JSON.stringify(mockResponse), {
        status: 200,
        headers: { 'Content-Type': 'application/json' },
      })
    })

    const response = await fetch('https://example.com/api/test')
    const data = await response.json()

    expect(data).toEqual(mockResponse)
    expect(spyFetch).toHaveBeenCalledWith('https://example.com/api/test')
  })

  test('should mock fetch with error response', async () => {
    spyFetch.mockImplementation(async () => {
      return new Response('Not Found', {
        status: 404,
        statusText: 'Not Found',
      })
    })

    const response = await fetch('https://example.com/api/missing')

    expect(response.status).toBe(404)
    expect(response.statusText).toBe('Not Found')
    expect(spyFetch).toHaveBeenCalledTimes(1)
  })

  test('should mock fetch with different responses based on URL', async () => {
    spyFetch.mockImplementation(async (input: RequestInfo | URL) => {
      const url = typeof input === 'string' ? input : input.toString()

      if (url.includes('/sessions')) {
        return new Response(JSON.stringify({ sessions: [] }), {
          status: 200,
          headers: { 'Content-Type': 'application/json' },
        })
      } else if (url.includes('/conversation')) {
        return new Response(JSON.stringify({ messages: ['test'] }), {
          status: 200,
          headers: { 'Content-Type': 'application/json' },
        })
      }

      return new Response('Not Found', { status: 404 })
    })

    const sessionsResponse = await fetch('http://localhost:3000/api/sessions')
    const sessionsData = await sessionsResponse.json()
    expect(sessionsData).toEqual({ sessions: [] })

    const conversationResponse = await fetch('http://localhost:3000/api/conversation')
    const conversationData = await conversationResponse.json()
    expect(conversationData).toEqual({ messages: ['test'] })

    const notFoundResponse = await fetch('http://localhost:3000/api/unknown')
    expect(notFoundResponse.status).toBe(404)
  })

  test('should reset mock between tests', async () => {
    spyFetch.mockImplementation(async () => {
      return new Response('Test 1', { status: 200 })
    })

    await fetch('https://example.com/test1')
    expect(spyFetch).toHaveBeenCalledTimes(1)

    spyFetch.mockReset()

    spyFetch.mockImplementation(async () => {
      return new Response('Test 2', { status: 200 })
    })

    await fetch('https://example.com/test2')
    expect(spyFetch).toHaveBeenCalledTimes(1) // Should be 1, not 2
  })

  test('should handle Request object input', async () => {
    spyFetch.mockImplementation(async () => {
      return new Response(JSON.stringify({ ok: true }), {
        status: 200,
        headers: { 'Content-Type': 'application/json' },
      })
    })

    const request = new Request('http://localhost:3000/api/test', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ test: true }),
    })

    const response = await fetch(request)
    const data = await response.json()

    expect(data).toEqual({ ok: true })
    expect(spyFetch).toHaveBeenCalledWith(request)
  })
})
