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

import {
  CONVERSION_CAPTURE_VERSION,
  CONVERSION_INTERACTION_TYPES,
  attachConversionSink,
  classifyHref,
  createConversionTracker,
  hashTarget,
  isConversionType,
  redactHref,
  type ConversionEvent,
} from './useConversionTracking'

/**
 * These tests protect three properties, in order of how expensive they are to lose:
 *
 *  1. Conversion events survive a DEFERRED telemetry SDK (fleet P3 interlock). A click
 *     captured before any sink exists must still arrive once one attaches.
 *  2. Classification order is stable — booking beats same-origin and social, protocol
 *     beats everything. A silent reclassification turns booking revenue into `internal`.
 *  3. Delegated capture catches links the site never hand-wired. This is the whole reason
 *     the module exists: KEPT's `BookPTAppointmentClicked` died on 2026-06-03 because one
 *     branch of the header had no handler, and nothing failed.
 */

const HOST = 'kineticenergypt.com'

function setHost(host: string) {
  // jsdom's location is not writable; stub the pieces the module reads.
  Object.defineProperty(window, 'location', {
    configurable: true,
    value: { hostname: host, pathname: '/' } as Location,
  })
}

function anchor(html: string): HTMLAnchorElement {
  document.body.innerHTML = html
  const el = document.body.querySelector('a')
  if (!el) throw new Error('fixture has no anchor')
  return el
}

// jsdom cannot navigate; without this every anchor click logs "Not implemented:
// navigation to another Document". Bubble-phase, so the tracker's capture-phase
// listener still sees the click exactly as a browser would.
const swallowNavigation = (event: Event) => event.preventDefault()

beforeEach(() => {
  setHost(HOST)
  document.body.innerHTML = ''
  document.addEventListener('click', swallowNavigation)
})

afterEach(() => {
  document.removeEventListener('click', swallowNavigation)
  vi.restoreAllMocks()
  document.body.innerHTML = ''
})

describe('classifyHref — order is load-bearing', () => {
  const opts = {
    pageHost: HOST,
    bookingHosts: ['stridethera.com', 'momence.com', 'vagaro.com'],
    bookingPaths: ['/book'],
    socialHosts: ['facebook.com', 'instagram.com'],
  }

  it('protocol wins first: tel: and sms: are phone, mailto: is email', () => {
    expect(classifyHref('tel:+19708798026', opts)).toBe('phone')
    expect(classifyHref('sms:+19708798026', opts)).toBe('phone')
    expect(classifyHref('mailto:frontdesk@kineticenergypt.com', opts)).toBe('email')
  })

  it('booking vendors are booking, including subdomains', () => {
    expect(
      classifyHref('https://app.stridethera.com/patient-scheduling/1feed7e0', opts),
    ).toBe('booking')
    expect(classifyHref('https://www.vagaro.com/us04/justposhesthetics/services', opts)).toBe(
      'booking',
    )
    expect(classifyHref('https://momence.com/appointments/x', opts)).toBe('booking')
  })

  it('booking beats same-origin: a self-hosted /book path is revenue, not internal', () => {
    expect(classifyHref('/book/pt', opts)).toBe('booking')
    expect(classifyHref('/gym', opts)).toBe('internal')
  })

  it('social, external and internal fall out in that order', () => {
    expect(classifyHref('https://www.instagram.com/kinetic_energy_pt', opts)).toBe('social')
    expect(classifyHref('https://example.com/whatever', opts)).toBe('external')
    expect(classifyHref(`https://${HOST}/staff`, opts)).toBe('internal')
  })

  it('non-navigational anchors are buttons, not conversions', () => {
    expect(classifyHref('#', opts)).toBe('button')
    expect(classifyHref('javascript:void(0)', opts)).toBe('button')
    expect(classifyHref('', opts)).toBe('button')
  })
})

describe('capture — delegated, so un-wired links are still counted', () => {
  it('captures a booking link that has no click handler of its own', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    // Deliberately mirrors the KEPT header CTA that lost its handler.
    const el = anchor(
      `<a href="https://app.stridethera.com/patient-scheduling/1feed7e0" target="_blank">Book Online</a>`,
    )
    el.click()

    expect(events).toHaveLength(1)
    expect(events[0].name).toBe('site_interaction')
    expect(events[0].properties.interaction_type).toBe('booking')
    expect(events[0].properties.label).toBe('Book Online')
    expect(events[0].properties.href_host).toBe('app.stridethera.com')
    expect(events[0].properties.capture_version).toBe(CONVERSION_CAPTURE_VERSION)

    tracker.stop()
  })

  it('captures a tel: tap — the signal no DCS site measured before', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    anchor(`<a href="tel:+19708798026">(970) 879-8026</a>`).click()

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('phone')
    tracker.stop()
  })

  it('captures clicks on a child element of the link', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    document.body.innerHTML = `<a href="https://www.vagaro.com/us04/x/services"><span id="inner">Book an Appointment</span></a>`
    ;(document.getElementById('inner') as HTMLElement).click()

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('booking')
    tracker.stop()
  })

  it('strips query and fragment from the destination', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    anchor(
      `<a href="https://www.vagaro.com/services?email=someone%40example.com&name=Jane#top">Book</a>`,
    ).click()

    expect(events[0].properties.href).not.toContain('example.com')
    expect(events[0].properties.href).not.toContain('?')
    expect(events[0].properties.href).not.toContain('#')
    tracker.stop()
  })

  it('ignores clicks that are not on a link or button', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    document.body.innerHTML = `<p id="text">just prose</p>`
    ;(document.getElementById('text') as HTMLElement).click()

    expect(events).toHaveLength(0)
    tracker.stop()
  })

  it('collapses a duplicate fire of the same click', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    const el = anchor(`<a href="tel:+19708798026">Call</a>`)
    el.click()
    el.click()

    expect(events).toHaveLength(1)
    tracker.stop()
  })

  it('a throwing sink never breaks the page', () => {
    const tracker = createConversionTracker({
      sink: () => {
        throw new Error('transport down')
      },
    })
    tracker.start()

    expect(() => anchor(`<a href="tel:+1">Call</a>`).click()).not.toThrow()
    tracker.stop()
  })
})

describe('INTERLOCK — survives a deferred sink (fleet P3, App Insights deferral)', () => {
  it('buffers clicks captured before any sink exists, then flushes on attach', () => {
    const tracker = createConversionTracker() // no sink: SDK not loaded yet
    tracker.start()

    anchor(`<a href="https://www.vagaro.com/a/services">Book an Appointment</a>`).click()
    anchor(`<a href="tel:+12488815213">(248) 881-5213</a>`).click()

    // Nothing has been delivered — but nothing has been lost either.
    expect(tracker.buffered()).toHaveLength(2)

    const events: ConversionEvent[] = []
    tracker.attachSink((e) => events.push(e))

    expect(events.map((e) => e.properties.interaction_type)).toEqual(['booking', 'phone'])
    expect(tracker.buffered()).toHaveLength(0)

    // And it stays live afterwards.
    anchor(`<a href="https://www.vagaro.com/b/services">Book</a>`).click()
    expect(events).toHaveLength(3)

    tracker.stop()
  })

  it('attachConversionSink reaches a tracker the loader has no reference to', () => {
    const tracker = createConversionTracker()
    tracker.start()

    anchor(`<a href="https://www.vagaro.com/a/services">Book</a>`).click()

    const events: ConversionEvent[] = []
    const reached = attachConversionSink((e) => events.push(e))

    expect(reached).toBeGreaterThanOrEqual(1)
    expect(events).toHaveLength(1)

    tracker.stop()
    // stop() deregisters, so a later attach must not resurrect it.
    expect(attachConversionSink(() => {})).toBe(0)
  })

  it('the buffer is bounded, so a click-spamming bot cannot grow memory', () => {
    const tracker = createConversionTracker({ bufferLimit: 3 })
    tracker.start()

    for (let i = 0; i < 10; i += 1) {
      anchor(`<a href="https://www.vagaro.com/${i}/services">Book ${i}</a>`).click()
    }

    expect(tracker.buffered()).toHaveLength(3)
    // Oldest dropped, newest kept.
    expect(tracker.buffered()[2].properties.label).toBe('Book 9')
    tracker.stop()
  })
})

describe('configuration', () => {
  it('honours a custom event name (canonical dcs_conversion)', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({
      eventName: 'dcs_conversion',
      sink: (e) => events.push(e),
    })
    tracker.start()

    anchor(`<a href="tel:+1">Call</a>`).click()

    expect(events[0].name).toBe('dcs_conversion')
    tracker.stop()
  })

  it('accepts per-site booking hosts on top of the fleet defaults', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({
      bookingHosts: ['bookme.example'],
      sink: (e) => events.push(e),
    })
    tracker.start()

    anchor(`<a href="https://bookme.example/slot">Reserve</a>`).click()

    expect(events[0].properties.interaction_type).toBe('booking')
    tracker.stop()
  })

  it('stop() unbinds — no events after teardown', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()
    tracker.stop()

    anchor(`<a href="tel:+1">Call</a>`).click()

    expect(events).toHaveLength(0)
  })
})

describe('managed + bespoke form submits (C-326)', () => {
  function form(html: string): HTMLFormElement {
    document.body.innerHTML = html
    const el = document.body.querySelector('form')
    if (!el) throw new Error('fixture has no form')
    return el
  }

  it('counts a submitted form as a conversion', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    form(
      `<form><input name="email" /><button type="submit">Request a Consultation</button></form>`,
    ).dispatchEvent(new Event('submit', { bubbles: true, cancelable: true }))

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('form_submit')
    expect(events[0].properties.is_conversion).toBe('true')
    expect(events[0].properties.label).toBe('Request a Consultation')
    tracker.stop()
  })

  it('DOES NOT count the click on the submit button — only the submit that follows', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    const f = form(`<form><button type="submit">Send</button></form>`)
    const button = f.querySelector('button') as HTMLElement

    // A real browser fires click, then submit. Counting both would make every lead two.
    button.click()
    f.dispatchEvent(new Event('submit', { bubbles: true, cancelable: true }))

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('form_submit')
    tracker.stop()
  })

  it('a click that never becomes a submit (validation failed) is not a conversion', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    // HTML default: a typeless <button> inside a form IS a submit control — the shape
    // every <DcsForm> renders. Clicking it with the form invalid submits nothing.
    const f = form(`<form><button>Send</button></form>`)
    ;(f.querySelector('button') as HTMLElement).click()

    expect(events).toHaveLength(0)
    tracker.stop()
  })

  it('a non-submit button inside a form is still an ordinary button click', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    const f = form(`<form><button type="button">Add another photo</button></form>`)
    ;(f.querySelector('button') as HTMLElement).click()

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('button')
    expect(events[0].properties.is_conversion).toBe('false')
    tracker.stop()
  })

  it('captureFormSubmits: false restores the click-only behaviour', () => {
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({
      captureFormSubmits: false,
      sink: (e) => events.push(e),
    })
    tracker.start()

    const f = form(`<form><button type="submit">Send</button></form>`)
    ;(f.querySelector('button') as HTMLElement).click()
    f.dispatchEvent(new Event('submit', { bubbles: true, cancelable: true }))

    expect(events).toHaveLength(1)
    expect(events[0].properties.interaction_type).toBe('button')
    tracker.stop()
  })
})

describe('DOUBLE-COUNT RAIL — one delegated listener per document', () => {
  it('a second start() on the same document REFUSES and warns', () => {
    const warn = vi.spyOn(console, 'warn').mockImplementation(() => {})
    const first: ConversionEvent[] = []
    const second: ConversionEvent[] = []

    const a = createConversionTracker({ sink: (e) => first.push(e) })
    const b = createConversionTracker({ sink: (e) => second.push(e) })
    a.start()
    b.start()

    anchor(`<a href="tel:+12483852926">Call</a>`).click()

    // One click, one event. The refused tracker heard nothing.
    expect(first).toHaveLength(1)
    expect(second).toHaveLength(0)
    expect(warn).toHaveBeenCalledWith(expect.stringContaining('REFUSED'))

    a.stop()
    b.stop()
  })

  it('after stop(), the document is free again', () => {
    const a = createConversionTracker()
    a.start()
    a.stop()

    const events: ConversionEvent[] = []
    const b = createConversionTracker({ sink: (e) => events.push(e) })
    b.start()

    anchor(`<a href="tel:+1">Call</a>`).click()
    expect(events).toHaveLength(1)
    b.stop()
  })

  it('{ force: true } is the documented escape hatch and it really does double', () => {
    const warn = vi.spyOn(console, 'warn').mockImplementation(() => {})
    const events: ConversionEvent[] = []

    const a = createConversionTracker({ sink: (e) => events.push(e) })
    const b = createConversionTracker({ force: true, sink: (e) => events.push(e) })
    a.start()
    b.start()

    anchor(`<a href="tel:+1">Call</a>`).click()

    // Recorded deliberately: the hatch is real, and this is the damage it does.
    expect(events).toHaveLength(2)
    expect(warn).not.toHaveBeenCalled()
    a.stop()
    b.stop()
  })
})

describe('privacy — Do Not Track and redaction', () => {
  it('binds nothing at all under DNT', () => {
    Object.defineProperty(navigator, 'doNotTrack', { configurable: true, value: '1' })
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({ sink: (e) => events.push(e) })
    tracker.start()

    anchor(`<a href="tel:+12483852926">Call</a>`).click()

    expect(events).toHaveLength(0)
    expect(tracker.buffered()).toHaveLength(0)
    Object.defineProperty(navigator, 'doNotTrack', { configurable: true, value: undefined })
    tracker.stop()
  })

  it('respectDoNotTrack: false is honoured for first-party-only deployments', () => {
    Object.defineProperty(navigator, 'doNotTrack', { configurable: true, value: '1' })
    const events: ConversionEvent[] = []
    const tracker = createConversionTracker({
      respectDoNotTrack: false,
      sink: (e) => events.push(e),
    })
    tracker.start()

    anchor(`<a href="tel:+12483852926">Call</a>`).click()

    expect(events).toHaveLength(1)
    Object.defineProperty(navigator, 'doNotTrack', { configurable: true, value: undefined })
    tracker.stop()
  })

  it('redactHref leaves non-contact URLs intact but strips contact targets', () => {
    expect(redactHref('https://www.vagaro.com/x/services?e=a@b.com', HOST)).toEqual({
      href: 'https://www.vagaro.com/x/services',
      scheme: 'https:',
      hash: '',
    })

    const tel = redactHref('tel:+12483852926', HOST)
    expect(tel.scheme).toBe('tel:')
    expect(tel.href).not.toContain('2483852926')
    expect(tel.hash).toBe(hashTarget('+12483852926'))
  })

  it('classifies and flags every conversion type', () => {
    expect(CONVERSION_INTERACTION_TYPES).toEqual(['booking', 'phone', 'email', 'form_submit'])
    expect(isConversionType('phone')).toBe(true)
    expect(isConversionType('social')).toBe(false)
    expect(isConversionType('internal')).toBe(false)
  })
})