import { ref, readonly, computed } from 'vue'

interface BotCustomization {
  archetype?: string
  primaryColor?: string
  secondaryColor?: string
  forceVisor?: boolean
  forceMohawk?: boolean
  forceHorns?: boolean
}

interface BotData {
  id: string
  name: string
  avatarSeed: string
  archetype: string
  profilePicUrl: string | null
  customization: BotCustomization | null
  eloRating: number
  wins: number
  losses: number
  winStreak: number
  bestStreak: number
  tier: number
}

interface NostrWindow {
  getPublicKey(): Promise<string>
  signEvent(event: Record<string, unknown>): Promise<Record<string, unknown>>
  getRelays?(): Promise<Record<string, { read: boolean; write: boolean }>>
}

declare global {
  interface Window {
    nostr?: NostrWindow
  }
}

// Persist auth state across page navigations and HMR reloads
function loadStored<T>(key: string): T | null {
  try {
    const raw = localStorage.getItem(key)
    return raw ? JSON.parse(raw) : null
  } catch { return null }
}
function store(key: string, value: unknown) {
  if (value == null) localStorage.removeItem(key)
  else localStorage.setItem(key, JSON.stringify(value))
}

const pubkey = ref<string | null>(loadStored('bf_pubkey'))
const bot = ref<BotData | null>(loadStored('bf_bot'))
const profilePicUrl = ref<string | null>(loadStored('bf_pic'))
const isLoading = ref(false)

export function useNostr() {
  const isLoggedIn = computed(() => !!pubkey.value && !!bot.value)
  const hasExtension = computed(() => !!window.nostr)

  // Restore session on first load — re-verify with server
  if (pubkey.value && !bot.value) {
    fetch('/api/auth/login', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ pubkey: pubkey.value }),
    }).then(r => r.json()).then(data => {
      if (data.exists) {
        bot.value = data.bot
        store('bf_bot', data.bot)
      }
    }).catch(() => {})
  }

  async function login(): Promise<{ pubkey: string; bot: BotData | null }> {
    if (!window.nostr) {
      throw new Error('No Nostr extension found. Install nos2x, Alby, or another NIP-07 extension.')
    }

    isLoading.value = true
    try {
      const pk = await window.nostr.getPublicKey()
      pubkey.value = pk
      store('bf_pubkey', pk)

      // Fetch Nostr profile pic from relay
      const pic = await fetchNostrProfilePic(pk)
      if (pic) { profilePicUrl.value = pic; store('bf_pic', pic) }

      // Check if this pubkey has a bot
      const res = await fetch('/api/auth/login', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ pubkey: pk }),
      })

      if (res.ok) {
        const data = await res.json()
        if (data.exists) {
          bot.value = data.bot
          store('bf_bot', data.bot)
          return { pubkey: pk, bot: data.bot }
        }
      }

      return { pubkey: pk, bot: null }
    } finally {
      isLoading.value = false
    }
  }

  async function registerBot(name: string, webhookUrl: string, archetype: string): Promise<BotData> {
    if (!pubkey.value) throw new Error('Not logged in')

    const res = await fetch('/api/auth/register', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        pubkey: pubkey.value,
        name,
        webhookUrl,
        archetype,
        profilePicUrl: profilePicUrl.value,
      }),
    })

    const data = await res.json()
    if (!res.ok) throw new Error(data.error || 'Registration failed')

    bot.value = {
      id: data.id,
      name: data.name,
      avatarSeed: data.name,
      archetype: data.archetype,
      profilePicUrl: profilePicUrl.value,
      customization: data.customization || null,
      eloRating: 1200,
      wins: 0,
      losses: 0,
      winStreak: 0,
      bestStreak: 0,
      tier: 0,
    }
    store('bf_bot', bot.value)

    return bot.value
  }

  async function updateCustomization(customization: BotCustomization): Promise<void> {
    if (!pubkey.value) throw new Error('Not logged in')

    const res = await fetch('/api/auth/update', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ pubkey: pubkey.value, customization }),
    })

    if (!res.ok) {
      const data = await res.json()
      throw new Error(data.error || 'Update failed')
    }

    if (bot.value) {
      bot.value = {
        ...bot.value,
        customization: { ...(bot.value.customization || {}), ...customization },
        archetype: customization.archetype || bot.value.archetype,
      }
      store('bf_bot', bot.value)
    }
  }

  function logout() {
    pubkey.value = null
    bot.value = null
    profilePicUrl.value = null
    store('bf_pubkey', null)
    store('bf_bot', null)
    store('bf_pic', null)
  }

  return {
    pubkey: readonly(pubkey),
    bot: readonly(bot),
    profilePicUrl: readonly(profilePicUrl),
    isLoggedIn,
    isLoading: readonly(isLoading),
    hasExtension,
    login,
    registerBot,
    updateCustomization,
    logout,
  }
}

// Fetch profile picture from a Nostr relay
async function fetchNostrProfilePic(pk: string): Promise<string | null> {
  const relays = [
    'wss://relay.damus.io',
    'wss://relay.nostr.band',
    'wss://nos.lol',
  ]

  for (const relay of relays) {
    try {
      const pic = await queryRelay(relay, pk)
      if (pic) return pic
    } catch {
      continue
    }
  }
  return null
}

function queryRelay(url: string, pk: string): Promise<string | null> {
  return new Promise((resolve) => {
    const timeout = setTimeout(() => {
      ws.close()
      resolve(null)
    }, 3000)

    const ws = new WebSocket(url)
    const subId = Math.random().toString(36).slice(2, 10)

    ws.onopen = () => {
      // Request kind 0 (metadata) for this pubkey
      ws.send(JSON.stringify(['REQ', subId, { kinds: [0], authors: [pk], limit: 1 }]))
    }

    ws.onmessage = (msg) => {
      try {
        const data = JSON.parse(msg.data)
        if (data[0] === 'EVENT' && data[2]?.kind === 0) {
          const meta = JSON.parse(data[2].content)
          clearTimeout(timeout)
          ws.close()
          resolve(meta.picture || null)
        } else if (data[0] === 'EOSE') {
          clearTimeout(timeout)
          ws.close()
          resolve(null)
        }
      } catch {
        // ignore parse errors
      }
    }

    ws.onerror = () => {
      clearTimeout(timeout)
      resolve(null)
    }
  })
}