import { describe, it, expect, vi, beforeEach } from 'vitest'
import { flushPromises } from '@vue/test-utils'
import axios from 'axios'
import { useFeeds } from '../useFeeds'

vi.mock('axios')

class FakeIntersectionObserver {
  observe() {}
  unobserve() {}
  disconnect() {}
}
vi.stubGlobal('IntersectionObserver', FakeIntersectionObserver)

describe('useFeeds', () => {
  const { feeds, allItems, feedFilter, feedTitles, unreadCount, setFeedFilter, showMessage, message, showModal, fetchData, sync, getReadable, setInitialLoad, handleIntersection, markAllRead } = useFeeds()

  beforeEach(() => {
    localStorage.setItem('user-token', 'test-token')
    localStorage.setItem('user-id', '7')
    vi.clearAllMocks()

    feeds.value = []
    allItems.value = []
    feedFilter.value = null
    showMessage.value = false
    message.value = ''
    showModal.value = false
  })

  it('fetches and flattens articles for the current user', async () => {
    axios.get.mockResolvedValueOnce({
      data: {
        feeds: [
          {
            title: 'My Feed',
            items: [
              {
                id: 1,
                title: 'Article one',
                content: '<p>hello</p>',
                url: 'https://example.test/1',
                timestamp: '2026-01-01 10:00:00',
              },
            ],
          },
        ],
      },
    })

    await fetchData()

    expect(axios.get).toHaveBeenCalledWith('/api/v1/article/get/7', expect.anything())
    expect(feeds.value).toHaveLength(1)
    expect(feeds.value[0]).toMatchObject({ title: 'Article one', feedTitle: 'My Feed' })
  })

  it('sorts articles by timestamp across feeds, newest first', async () => {
    axios.get.mockResolvedValueOnce({
      data: {
        feeds: [
          {
            title: 'Old Feed',
            items: [
              { id: 1, title: 'Older article', content: '', url: 'https://example.test/1', timestamp: '2026-01-01 10:00:00' },
            ],
          },
          {
            title: 'New Feed',
            items: [
              { id: 2, title: 'Newer article', content: '', url: 'https://example.test/2', timestamp: '2026-02-01 10:00:00' },
            ],
          },
        ],
      },
    })

    await fetchData()

    expect(feeds.value.map(f => f.title)).toEqual(['Newer article', 'Older article'])
  })

  it('syncs feeds for the current user and refetches', async () => {
    axios.post.mockResolvedValueOnce({ status: 200 })
    axios.get.mockResolvedValue({ data: { feeds: [] } })

    await sync()

    expect(axios.post).toHaveBeenCalledWith(
      '/api/v1/article/sync',
      { user_id: 7 },
      expect.anything(),
    )
    expect(axios.get).toHaveBeenCalledWith('/api/v1/article/get/7', expect.anything())
  })

  it('marks the correct articles read when several scroll out of view in one batch', async () => {
    feeds.value = [
      { id: 101, title: 'First' },
      { id: 102, title: 'Second' },
      { id: 103, title: 'Third' },
    ]
    setInitialLoad(true)
    axios.put.mockResolvedValue({ status: 200 })

    // Both the first and second articles scrolled above the viewport in the
    // same IntersectionObserver callback — their `target.id` reflects their
    // original render-time indices (0 and 1).
    await handleIntersection([
      { isIntersecting: false, boundingClientRect: { y: -10 }, target: { id: '0' } },
      { isIntersecting: false, boundingClientRect: { y: -5 }, target: { id: '1' } },
    ])

    expect(axios.put).toHaveBeenCalledWith('/api/v1/article/read/101', null, expect.anything())
    expect(axios.put).toHaveBeenCalledWith('/api/v1/article/read/102', null, expect.anything())
    expect(axios.put).not.toHaveBeenCalledWith('/api/v1/article/read/103', null, expect.anything())
    expect(feeds.value).toEqual([{ id: 103, title: 'Third' }])

    setInitialLoad(false)
  })

  describe('feed filter', () => {
    const twoFeedsResponse = {
      data: {
        feeds: [
          {
            title: 'Feed A',
            items: [
              { id: 1, title: 'A1', content: '', url: 'https://example.test/a1', timestamp: '2026-01-01 10:00:00' },
              { id: 3, title: 'A2', content: '', url: 'https://example.test/a2', timestamp: '2026-01-03 10:00:00' },
            ],
          },
          {
            title: 'Feed B',
            items: [
              { id: 2, title: 'B1', content: '', url: 'https://example.test/b1', timestamp: '2026-01-02 10:00:00' },
            ],
          },
        ],
      },
    }

    it('narrows the displayed list to a single feed and restores it on "All feeds"', async () => {
      axios.get.mockResolvedValueOnce(twoFeedsResponse)
      await fetchData()

      // Options are the distinct feed titles, sorted.
      expect(feedTitles.value).toEqual(['Feed A', 'Feed B'])
      // Unfiltered: everything, newest first (Jan 3, Jan 2, Jan 1).
      expect(feeds.value.map(f => f.id)).toEqual([3, 2, 1])

      await setFeedFilter('Feed A')
      expect(feeds.value.map(f => f.id)).toEqual([3, 1])

      await setFeedFilter(null)
      expect(feeds.value.map(f => f.id)).toEqual([3, 2, 1])
    })

    it('does not resurrect read articles when the filter is cleared', async () => {
      axios.get.mockResolvedValueOnce(twoFeedsResponse)
      axios.put.mockResolvedValue({ status: 200 })
      await fetchData()

      await setFeedFilter('Feed A')
      setInitialLoad(true)

      // The first Feed A article scrolls above the viewport → marked read and
      // dropped from both the filtered list and the master.
      await handleIntersection([
        { isIntersecting: false, boundingClientRect: { y: -10 }, target: { id: '0' } },
      ])
      setInitialLoad(false)

      expect(feeds.value.map(f => f.id)).toEqual([1])

      await setFeedFilter(null)
      // Article 3 stays gone; the still-unread articles remain, newest first.
      expect(feeds.value.map(f => f.id)).toEqual([2, 1])
    })

    it('keeps an emptied filtered feed selected and selectable, showing "All caught up"', async () => {
      axios.get.mockResolvedValueOnce(twoFeedsResponse)
      axios.put.mockResolvedValue({ status: 200 })
      await fetchData()

      await setFeedFilter('Feed B')
      expect(feeds.value.map(f => f.id)).toEqual([2])

      // Mark all (visible = just Feed B) read — Feed B has no unread items left.
      vi.spyOn(window, 'confirm').mockReturnValue(true)
      await markAllRead()

      // The list empties, but the filter stays put and the feed remains a
      // selectable option (so the <select> never dangles) even though it no
      // longer has unread items.
      expect(feeds.value).toEqual([])
      expect(feedFilter.value).toBe('Feed B')
      expect(feedTitles.value).toEqual(['Feed A', 'Feed B'])

      // Switching away drops the now-empty feed from the options.
      await setFeedFilter(null)
      expect(feedTitles.value).toEqual(['Feed A'])
      expect(feeds.value.map(f => f.id)).toEqual([3, 1])
    })

    it('counts unread items in the selected feed when a filter is active, else the global total', async () => {
      axios.get.mockResolvedValueOnce(twoFeedsResponse)
      await fetchData()

      // No filter: global unread total across both feeds.
      expect(unreadCount.value).toBe(3)

      // Filtered: only the selected feed's unread items.
      await setFeedFilter('Feed B')
      expect(unreadCount.value).toBe(1)
      await setFeedFilter('Feed A')
      expect(unreadCount.value).toBe(2)

      await setFeedFilter(null)
      expect(unreadCount.value).toBe(3)
    })
  })

  it('strips leftover embedded-video placeholder headings', async () => {
    feeds.value = [{
      id: 1,
      title: 'Article one',
      url: 'https://www.dw.com/en/article-one/a-1',
      content: '',
    }]
    axios.post.mockResolvedValueOnce({
      data: {
        content: `<html><body><article>
          <h2 aria-label="Eingebettetes Video — Iran-Krieg belastet Wirtschaft und Märkte in Deutschland">
            <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20"><g fill-rule="evenodd"><path d="M14.114 7.599H13.5l.002 4.706h.601l4.582 3.25-.005-11.11zM11.084 4.444l-9.007.002-1.336.797.002 9.514 1.334.793 9.007.006 1.509-.799-.004-9.516z"></path></g></svg>
            Iran-Krieg belastet Wirtschaft und Märkte in Deutschland
          </h2>
          <p>some article text long enough for readability to keep the paragraph as the main content body, padded with extra words to pass the content-length heuristics used by Mozilla Readability when scoring candidate nodes.</p>
        </article></body></html>`,
      },
    })

    await getReadable(feeds.value[0], 0)

    expect(feeds.value[0].content).not.toContain('Eingebettetes Video')
    expect(feeds.value[0].content).not.toContain('<svg')
  })

  it('strips leftover embedded-audio placeholder headings', async () => {
    feeds.value = [{
      id: 1,
      title: 'Article one',
      url: 'https://www.dw.com/en/article-one/a-1',
      content: '',
    }]
    axios.post.mockResolvedValueOnce({
      data: {
        content: `<html><body><article>
          <h2 aria-label="Eingebetteter Audio-Beitrag — Der Gender Pay Gap existiert noch immer">
            <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20"><g fill-rule="evenodd"><path d="M14.114 7.599H13.5l.002 4.706h.601l4.582 3.25-.005-11.11zM11.084 4.444l-9.007.002-1.336.797.002 9.514 1.334.793 9.007.006 1.509-.799-.004-9.516z"></path></g></svg>
            Der Gender Pay Gap existiert noch immer
          </h2>
          <p>some article text long enough for readability to keep the paragraph as the main content body, padded with extra words to pass the content-length heuristics used by Mozilla Readability when scoring candidate nodes.</p>
        </article></body></html>`,
      },
    })

    await getReadable(feeds.value[0], 0)

    expect(feeds.value[0].content).not.toContain('Eingebetteter Audio-Beitrag')
    expect(feeds.value[0].content).not.toContain('<svg')
  })

  it('resolves Deutsche-Welle-style templated image URLs from data-format/data-url', async () => {
    feeds.value = [{
      id: 1,
      title: 'Article one',
      url: 'https://www.dw.com/en/article-one/a-1',
      content: '',
    }]
    axios.post.mockResolvedValueOnce({
      data: {
        content: `<html><body><article>
          <img data-format="MASTER_LANDSCAPE" data-id="76212061"
               data-url="https://static.dw.com/image/76212061_\${formatId}.jpg"
               data-aspect-ratio="16/9" alt="Merz and Trump"
               src="https://static.dw.com/image/76212061_$%7BformatId%7D.jpg">
          <p>some article text long enough for readability to keep the image and paragraph together in the parsed output, padded with extra words to pass the content-length heuristics used by Mozilla Readability when scoring candidate nodes for the main article body.</p>
        </article></body></html>`,
      },
    })

    await getReadable(feeds.value[0], 0)

    // "MASTER_LANDSCAPE" is a symbolic name from DW's CMS, not a valid value
    // for the CDN's numeric `formatId` — it must be mapped to "6" or the
    // resulting URL 400s and the image fails to load.
    expect(feeds.value[0].content).toContain('src="https://static.dw.com/image/76212061_6.jpg"')
    // The rendered `src` is what matters — `data-url` retaining the raw
    // template is harmless since browsers don't load images from data-* attrs.
    expect(feeds.value[0].content).not.toMatch(/src="[^"]*(\$\{|%7[bB])/)
  })

  it('resolves templated images regardless of the placeholder name and scrubs other lazy-load attributes', async () => {
    feeds.value = [{
      id: 1,
      title: 'Article one',
      url: 'https://www.dw.com/en/article-one/a-1',
      content: '',
    }]
    axios.post.mockResolvedValueOnce({
      data: {
        content: `<html><body><article>
          <img data-format="MASTER_LANDSCAPE" data-id="76212061"
               data-url="https://static.dw.com/image/76212061_\${size}.jpg"
               data-src="https://static.dw.com/image/76212061_\${size}.jpg"
               alt="Merz and Trump" src="data:image/gif;base64,placeholder">
          <p>some article text long enough for readability to keep the image and paragraph together in the parsed output, padded with extra words to pass the content-length heuristics used by Mozilla Readability when scoring candidate nodes for the main article body.</p>
        </article></body></html>`,
      },
    })

    await getReadable(feeds.value[0], 0)

    // `${size}` isn't the hardcoded `${formatId}` placeholder, but `data-format`
    // is still the right substitution — and lazy-load attributes like `data-src`
    // (which Readability may promote into `src`) must be cleaned too, not just
    // `data-url`, so a stale template can't resurface in the rendered output.
    expect(feeds.value[0].content).not.toMatch(/src="[^"]*(\$\{|%7[bB])/)
  })

  it('drops unresolvable templated images instead of leaving a broken src', async () => {
    feeds.value = [{
      id: 1,
      title: 'Article one',
      url: 'https://example.test/article-one',
      content: '',
    }]
    axios.post.mockResolvedValueOnce({
      data: {
        content: `<html><body><article>
          <img data-url="https://example.test/img_\${size}.jpg" src="https://example.test/img_%7Bsize%7D.jpg">
          <p>some article text long enough for readability to keep the paragraph as the main content body, padded with extra words to pass the content-length heuristics used by Mozilla Readability when scoring candidate nodes.</p>
        </article></body></html>`,
      },
    })

    await getReadable(feeds.value[0], 0)

    expect(feeds.value[0].content).not.toContain('%7Bsize%7D')
    expect(feeds.value[0].content).not.toContain('<img')
  })
})