import { describe, expect, it, vi, beforeEach } from 'vitest'

import { fetchModelMetadata } from './missingModelsUtils'

const fetchMock = vi.fn()
vi.stubGlobal('fetch', fetchMock)

vi.mock('@/platform/distribution/types', () => ({ isDesktop: false }))
vi.mock('@/stores/electronDownloadStore', () => ({}))

let testId = 0

describe('fetchModelMetadata', () => {
  beforeEach(() => {
    fetchMock.mockReset()
    testId++
  })

  it('fetches file size via HEAD for non-Civitai URLs', async () => {
    fetchMock.mockResolvedValueOnce({
      ok: true,
      headers: new Headers({ 'content-length': '1048576' })
    })

    const url = `https://huggingface.co/org/model/resolve/main/head-${testId}.safetensors`
    const metadata = await fetchModelMetadata(url)
    expect(metadata.fileSize).toBe(1048576)
    expect(metadata.gatedRepoUrl).toBeNull()
    expect(fetchMock).toHaveBeenCalledWith(url, { method: 'HEAD' })
  })

  it('uses Civitai API for Civitai model URLs', async () => {
    const url = `https://civitai.com/api/download/models/${testId}`
    fetchMock.mockResolvedValueOnce({
      ok: true,
      json: async () => ({
        files: [{ sizeKB: 1024, downloadUrl: url }]
      })
    })

    const metadata = await fetchModelMetadata(url)
    expect(metadata.fileSize).toBe(1024 * 1024)
    expect(metadata.gatedRepoUrl).toBeNull()
    expect(fetchMock).toHaveBeenCalledWith(
      `https://civitai.com/api/v1/model-versions/${testId}`
    )
  })

  it('returns null fileSize when Civitai API fails', async () => {
    fetchMock.mockResolvedValueOnce({ ok: false })

    const metadata = await fetchModelMetadata(
      `https://civitai.com/api/download/models/${testId}`
    )
    expect(metadata.fileSize).toBeNull()
    expect(metadata.gatedRepoUrl).toBeNull()
    expect(fetchMock).toHaveBeenCalledTimes(1)
  })

  it('returns gatedRepoUrl for gated HuggingFace HEAD requests (403)', async () => {
    fetchMock.mockResolvedValueOnce({ ok: false, status: 403 })

    const metadata = await fetchModelMetadata(
      `https://huggingface.co/bfl/FLUX.1/resolve/main/gated-${testId}.safetensors`
    )
    expect(metadata.gatedRepoUrl).toBe('https://huggingface.co/bfl/FLUX.1')
    expect(metadata.fileSize).toBeNull()
  })

  it('does not treat HuggingFace 404/500 as gated', async () => {
    fetchMock.mockResolvedValueOnce({ ok: false, status: 404 })

    const metadata = await fetchModelMetadata(
      `https://huggingface.co/org/model/resolve/main/notfound-${testId}.safetensors`
    )
    expect(metadata.gatedRepoUrl).toBeNull()
    expect(metadata.fileSize).toBeNull()
  })

  it('returns null for unrecognized Civitai URL patterns', async () => {
    const url = `https://civitai.com/api/v1/models/${testId}`
    const metadata = await fetchModelMetadata(url)
    expect(metadata.fileSize).toBeNull()
    expect(metadata.gatedRepoUrl).toBeNull()
    expect(fetchMock).not.toHaveBeenCalled()
  })

  it('returns cached metadata on second call', async () => {
    const url = `https://huggingface.co/org/model/resolve/main/cached-${testId}.safetensors`

    fetchMock.mockResolvedValueOnce({
      ok: true,
      headers: new Headers({ 'content-length': '500' })
    })

    const first = await fetchModelMetadata(url)
    const second = await fetchModelMetadata(url)

    expect(first.fileSize).toBe(500)
    expect(second.fileSize).toBe(500)
    expect(fetchMock).toHaveBeenCalledTimes(1)
  })

  it('does not cache incomplete results so retries are possible', async () => {
    const url = `https://example.com/retry-${testId}.safetensors`

    fetchMock
      .mockResolvedValueOnce({
        ok: true,
        headers: new Headers({})
      })
      .mockResolvedValueOnce({
        ok: true,
        headers: new Headers({ 'content-length': '1024' })
      })

    const first = await fetchModelMetadata(url)
    const second = await fetchModelMetadata(url)

    expect(first.fileSize).toBeNull()
    expect(second.fileSize).toBe(1024)
    expect(fetchMock).toHaveBeenCalledTimes(2)
  })

  it('deduplicates concurrent requests for the same URL', async () => {
    const url = `https://huggingface.co/org/model/resolve/main/dedup-${testId}.safetensors`

    fetchMock.mockResolvedValueOnce({
      ok: true,
      headers: new Headers({ 'content-length': '2048' })
    })

    const [first, second] = await Promise.all([
      fetchModelMetadata(url),
      fetchModelMetadata(url)
    ])

    expect(first.fileSize).toBe(2048)
    expect(second.fileSize).toBe(2048)
    expect(fetchMock).toHaveBeenCalledTimes(1)
  })
})