import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
import { setActivePinia, createPinia } from 'pinia'
import { useGalleryStore } from '../src/stores/gallery.js'

function stubFetch(handler) {
  globalThis.fetch = vi.fn(async (url, init) => {
    const { status, body } = handler(url, init)
    return {
      ok: status >= 200 && status < 300,
      status,
      statusText: String(status),
      text: async () => (body == null ? '' : JSON.stringify(body))
    }
  })
}

const EMPTY = { images: [], date_groups: [], next_cursor: null }

describe('gallery store: tag/post filter exclusivity', () => {
  beforeEach(() => setActivePinia(createPinia()))
  afterEach(() => vi.restoreAllMocks())

  it('setPostFilter sets post_id and clears tag_id', () => {
    const s = useGalleryStore()
    stubFetch(() => ({ status: 200, body: EMPTY }))
    s.setTagFilter(3)
    expect(s.filter.tag_id).toBe(3)
    s.setPostFilter(7)
    expect(s.filter.post_id).toBe(7)
    expect(s.filter.tag_id).toBe(null)
  })

  it('setTagFilter clears post_id', () => {
    const s = useGalleryStore()
    stubFetch(() => ({ status: 200, body: EMPTY }))
    s.setPostFilter(7)
    s.setTagFilter(3)
    expect(s.filter.tag_id).toBe(3)
    expect(s.filter.post_id).toBe(null)
  })

  it('loadMore sends exactly the active filter param', async () => {
    const s = useGalleryStore()
    const urls = []
    stubFetch((url) => { urls.push(url); return { status: 200, body: EMPTY } })
    s.setPostFilter(7)
    await s.loadMore()
    const scrollCall = urls.filter(u => u.includes('/api/gallery/scroll')).pop()
    expect(scrollCall).toContain('post_id=7')
    expect(scrollCall).not.toContain('tag_id=')
  })

  it('setTagFilter resolves the tag name for the filter chip', async () => {
    const s = useGalleryStore()
    stubFetch((url) => {
      if (url.includes('/api/tags/7')) {
        return { status: 200, body: { id: 7, name: 'Asuka', kind: 'character' } }
      }
      return { status: 200, body: EMPTY }  // scroll + timeline
    })
    s.setTagFilter(7)
    expect(s.filter.tag_id).toBe(7)
    await vi.waitFor(() => expect(s.filterTagName).toBe('Asuka'))
  })

  it('loadInitial issues exactly one scroll request at the initial limit', async () => {
    const s = useGalleryStore()
    const urls = []
    // Non-null cursor: the old 10×serial-batch loop would have fired ten
    // requests here. The single-fetch path must fire exactly one.
    stubFetch((url) => {
      urls.push(url)
      return { status: 200, body: { images: [], date_groups: [], next_cursor: 'c1' } }
    })
    await s.loadInitial()
    const scrollCalls = urls.filter(u => u.includes('/api/gallery/scroll'))
    expect(scrollCalls).toHaveLength(1)
    expect(scrollCalls[0]).toContain('limit=50')
  })
})