/**
 * NDK Initialization Patterns
 * 
 * Examples from: src/lib/stores/ndk.ts
 */

import NDK from '@nostr-dev-kit/ndk'

// ============================================================
// BASIC INITIALIZATION
// ============================================================

const basicInit = () => {
  const ndk = new NDK({
    explicitRelayUrls: ['wss://relay.damus.io', 'wss://relay.nostr.band']
  })
  
  return ndk
}

// ============================================================
// PRODUCTION PATTERN - WITH MULTIPLE NDK INSTANCES
// ============================================================

const productionInit = (relays: string[], zapRelays: string[]) => {
  // Main NDK instance for general operations
  const ndk = new NDK({
    explicitRelayUrls: relays
  })
  
  // Separate NDK for zap operations (performance optimization)
  const zapNdk = new NDK({
    explicitRelayUrls: zapRelays
  })
  
  return { ndk, zapNdk }
}

// ============================================================
// CONNECTION WITH TIMEOUT
// ============================================================

const connectWithTimeout = async (
  ndk: NDK, 
  timeoutMs: number = 10000
): Promise<void> => {
  // Create connection promise
  const connectPromise = ndk.connect()
  
  // Create timeout promise
  const timeoutPromise = new Promise<never>((_, reject) =>
    setTimeout(() => reject(new Error('Connection timeout')), timeoutMs)
  )
  
  try {
    // Race between connection and timeout
    await Promise.race([connectPromise, timeoutPromise])
    console.log('✅ NDK connected successfully')
  } catch (error) {
    if (error instanceof Error && error.message === 'Connection timeout') {
      console.error('❌ Connection timed out after', timeoutMs, 'ms')
    } else {
      console.error('❌ Connection failed:', error)
    }
    throw error
  }
}

// ============================================================
// FULL INITIALIZATION FLOW
// ============================================================

interface InitConfig {
  relays?: string[]
  zapRelays?: string[]
  timeoutMs?: number
}

const defaultRelays = [
  'wss://relay.damus.io',
  'wss://relay.nostr.band',
  'wss://nos.lol'
]

const defaultZapRelays = [
  'wss://relay.damus.io',
  'wss://nostr.wine'
]

const initializeNDK = async (config: InitConfig = {}) => {
  const {
    relays = defaultRelays,
    zapRelays = defaultZapRelays,
    timeoutMs = 10000
  } = config
  
  // Initialize instances
  const ndk = new NDK({ explicitRelayUrls: relays })
  const zapNdk = new NDK({ explicitRelayUrls: zapRelays })
  
  // Connect with timeout protection
  try {
    await connectWithTimeout(ndk, timeoutMs)
    await connectWithTimeout(zapNdk, timeoutMs)
    
    return { ndk, zapNdk, isConnected: true }
  } catch (error) {
    return { ndk, zapNdk, isConnected: false, error }
  }
}

// ============================================================
// CHECKING CONNECTION STATUS
// ============================================================

const getConnectionStatus = (ndk: NDK) => {
  const connectedRelays = Array.from(ndk.pool?.relays.values() || [])
    .filter(relay => relay.status === 1)
    .map(relay => relay.url)
  
  const isConnected = connectedRelays.length > 0
  
  return {
    isConnected,
    connectedRelays,
    totalRelays: ndk.pool?.relays.size || 0
  }
}

// ============================================================
// USAGE EXAMPLE
// ============================================================

async function main() {
  // Initialize
  const { ndk, zapNdk, isConnected } = await initializeNDK({
    relays: defaultRelays,
    zapRelays: defaultZapRelays,
    timeoutMs: 10000
  })
  
  if (!isConnected) {
    console.error('Failed to connect to relays')
    return
  }
  
  // Check status
  const status = getConnectionStatus(ndk)
  console.log('Connection status:', status)
  
  // Ready to use
  console.log('NDK ready for operations')
}

export {
  basicInit,
  productionInit,
  connectWithTimeout,
  initializeNDK,
  getConnectionStatus
}