'use client'

import { useState } from 'react'

export type PersonalReferralPayload = {
  refToken: string
  firstName: string
  lastName: string
  email: string
  password: string
  phone: string
  lang?: 'de' | 'en'
}

export type CompanyReferralPayload = {
  refToken: string
  companyEmail: string
  password: string
  companyName: string
  companyPhone: string
  contactPersonName: string
  contactPersonPhone: string
  lang?: 'de' | 'en'
}

export type GuestReferralPayload = {
  refToken: string
  firstName: string
  lastName: string
  email: string
  password: string
  lang?: 'de' | 'en'
}

type RegisterResult<T = any> = {
  ok: boolean
  status: number
  data?: T | null
  message?: string
}

function detectLang(): 'de' | 'en' {
  if (typeof navigator !== 'undefined') {
    const n = navigator.language || ''
    if (n.toLowerCase().startsWith('de')) return 'de'
  }
  return 'en'
}

function mapError(status: number): string {
  switch (status) {
    case 404:
      return 'Referral token not found.'
    case 410:
      return 'Referral token expired or exhausted.'
    case 403:
      return 'Referral token is inactive.'
    case 400:
      return 'Invalid registration data or token validation failed.'
    default:
      return 'Registration failed. Please try again later.'
  }
}

// NEW: read ?ref from the URL as a fallback
function getRefTokenFromUrl(): string | null {
  if (typeof window === 'undefined') return null
  try {
    const u = new URL(window.location.href)
    return u.searchParams.get('ref')
  } catch {
    return null
  }
}

export function useRegister() {
  const [loading, setLoading] = useState(false)
  const [error, setError] = useState<string>('')

  const base = process.env.NEXT_PUBLIC_API_BASE_URL || ''

  const registerPersonalReferral = async (payload: PersonalReferralPayload): Promise<RegisterResult> => {
    setError('')
    setLoading(true)

    // Resolve token: prefer payload, fallback to URL
    const finalRefToken = (payload.refToken || '').trim() || getRefTokenFromUrl() || ''
    const body = { ...payload, refToken: finalRefToken, lang: payload.lang || detectLang() }

    // NOTE: align with other endpoints using /api prefix
    const url = `${base}/api/register/personal-referral`
    console.log('🌐 useRegister: POST personal-referral', { url, refToken: finalRefToken ? `${finalRefToken.slice(0, 6)}…${finalRefToken.slice(-6)}` : null })

    try {
      const res = await fetch(url, {
        method: 'POST',
        credentials: 'include',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body),
      })
      const json = await res.json().catch(() => null)
      console.log('📡 useRegister: personal status:', res.status, 'body:', json)
      if (!res.ok) {
        const msg = json?.message || mapError(res.status)
        setError(msg)
        return { ok: false, status: res.status, data: json, message: msg }
      }
      return { ok: true, status: res.status, data: json, message: json?.message }
    } catch (e) {
      console.error('❌ useRegister: personal error:', e)
      const msg = 'Network error. Please try again later.'
      setError(msg)
      return { ok: false, status: 0, data: null, message: msg }
    } finally {
      setLoading(false)
    }
  }

  const registerCompanyReferral = async (payload: CompanyReferralPayload): Promise<RegisterResult> => {
    setError('')
    setLoading(true)

    // Resolve token: prefer payload, fallback to URL
    const finalRefToken = (payload.refToken || '').trim() || getRefTokenFromUrl() || ''
    const body = { ...payload, refToken: finalRefToken, lang: payload.lang || detectLang() }

    // NOTE: align with other endpoints using /api prefix
    const url = `${base}/api/register/company-referral`
    console.log('🌐 useRegister: POST company-referral', { url, refToken: finalRefToken ? `${finalRefToken.slice(0, 6)}…${finalRefToken.slice(-6)}` : null })

    try {
      const res = await fetch(url, {
        method: 'POST',
        credentials: 'include',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body),
      })
      const json = await res.json().catch(() => null)
      console.log('📡 useRegister: company status:', res.status, 'body:', json)
      if (!res.ok) {
        const msg = json?.message || mapError(res.status)
        setError(msg)
        return { ok: false, status: res.status, data: json, message: msg }
      }
      return { ok: true, status: res.status, data: json, message: json?.message }
    } catch (e) {
      console.error('❌ useRegister: company error:', e)
      const msg = 'Network error. Please try again later.'
      setError(msg)
      return { ok: false, status: 0, data: null, message: msg }
    } finally {
      setLoading(false)
    }
  }

  const registerGuest = async (payload: GuestReferralPayload): Promise<RegisterResult> => {
    setError('')
    setLoading(true)

    const body = {
      firstName: payload.firstName,
      lastName: payload.lastName,
      email: payload.email,
      confirmEmail: payload.email,
      password: payload.password,
      confirmPassword: payload.password,
      referralEmail: undefined as string | undefined,
      lang: payload.lang || detectLang(),
    }

    // Try to resolve referral email from token
    if (payload.refToken) {
      try {
        const infoRes = await fetch(`${base}/api/referral/info/${encodeURIComponent(payload.refToken)}`, {
          method: 'GET',
          credentials: 'include',
        })
        const infoJson = await infoRes.json().catch(() => null)
        if (infoJson?.referrerEmail) {
          body.referralEmail = infoJson.referrerEmail
        }
      } catch {}
    }

    const url = `${base}/api/register/guest`
    console.log('🌐 useRegister: POST guest', { url })

    try {
      const res = await fetch(url, {
        method: 'POST',
        credentials: 'include',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body),
      })
      const json = await res.json().catch(() => null)
      console.log('📡 useRegister: guest status:', res.status, 'body:', json)
      if (!res.ok) {
        const msg = json?.message || mapError(res.status)
        setError(msg)
        return { ok: false, status: res.status, data: json, message: msg }
      }
      return { ok: true, status: res.status, data: json, message: json?.message }
    } catch (e) {
      console.error('❌ useRegister: guest error:', e)
      const msg = 'Network error. Please try again later.'
      setError(msg)
      return { ok: false, status: 0, data: null, message: msg }
    } finally {
      setLoading(false)
    }
  }

  return {
    loading,
    error,
    setError,
    registerPersonalReferral,
    registerCompanyReferral,
    registerGuest,
  }
}