import { Address } from 'viem'
import { AssembleClientConfig, PlatformFeeStats, ReferrerStats } from '../types'
import { ValidationError } from '../errors'
import { validateAddress } from '../utils'

/**
 * Manager for platform fee operations
 */
export class PlatformFeeManager {
  constructor(private config: AssembleClientConfig) {}

  /**
   * Calculate platform fee for a given amount
   */
  calculatePlatformFee(amount: bigint, feeBps: number): bigint {
    if (feeBps < 0 || feeBps > 10000) {
      throw new ValidationError('Fee basis points must be between 0 and 10000')
    }

    return (amount * BigInt(feeBps)) / 10000n
  }

  /**
   * Calculate total price including platform fee
   */
  calculateTotalPrice(basePrice: bigint, platformFeeBps?: number): bigint {
    if (!platformFeeBps || platformFeeBps === 0) {
      return basePrice
    }

    const platformFee = this.calculatePlatformFee(basePrice, platformFeeBps)
    return basePrice + platformFee
  }

  /**
   * Get platform fee earnings for a referrer (ETH)
   * Note: This requires tracking via event logs or off-chain indexing
   */
  async getPlatformFeeEarnings(referrer: Address): Promise<bigint> {
    validateAddress(referrer, 'referrer')

    // This would require:
    // 1. Filter all ticket purchase/tip events with platform fees
    // 2. Sum up fees earned by this referrer
    // 3. Account for any claimed fees

    console.warn('getPlatformFeeEarnings requires event log aggregation - returning 0 for now')
    return 0n
  }

  /**
   * Get platform fee earnings for a referrer for specific ERC20 token
   * Note: This requires tracking via event logs or off-chain indexing
   */
  async getPlatformFeeEarningsERC20(referrer: Address, token: Address): Promise<bigint> {
    validateAddress(referrer, 'referrer')
    validateAddress(token, 'token')

    // This would require:
    // 1. Filter all ERC20 ticket purchase/tip events with platform fees
    // 2. Filter by token address
    // 3. Sum up fees earned by this referrer
    // 4. Account for any claimed fees

    console.warn('getPlatformFeeEarningsERC20 requires event log aggregation - returning 0 for now')
    return 0n
  }

  /**
   * Get comprehensive platform fee statistics for a referrer
   */
  async getTotalPlatformFeesGenerated(referrer: Address): Promise<PlatformFeeStats> {
    validateAddress(referrer, 'referrer')

    // This would require comprehensive event log analysis
    // For now, returning zero stats

    console.warn('getTotalPlatformFeesGenerated requires event log aggregation - returning zero stats for now')
    
    return {
      totalEarnings: 0n,
      totalTransactions: 0,
      averageFee: 0n,
    }
  }

  /**
   * Get top referrers by platform fees earned
   */
  async getTopReferrers(limit: number = 10): Promise<ReferrerStats[]> {
    if (limit <= 0 || limit > 100) {
      throw new ValidationError('Limit must be between 1 and 100')
    }

    // This would require:
    // 1. Aggregate all platform fee events
    // 2. Group by referrer address
    // 3. Calculate totals and rank
    // 4. Return top N

    console.warn('getTopReferrers requires comprehensive event log aggregation - returning empty array for now')
    return []
  }

  /**
   * Calculate platform fee percentage from basis points
   */
  bpsToPercentage(bps: number): number {
    return bps / 100
  }

  /**
   * Calculate basis points from percentage
   */
  percentageToBps(percentage: number): number {
    if (percentage < 0 || percentage > 100) {
      throw new ValidationError('Percentage must be between 0 and 100')
    }
    return Math.round(percentage * 100)
  }

  /**
   * Validate platform fee basis points
   */
  validatePlatformFeeBps(feeBps: number): boolean {
    return feeBps >= 0 && feeBps <= 500 // Max 5% platform fee
  }

  /**
   * Get default platform fee for the protocol
   * Note: This would typically be stored in the contract
   */
  async getDefaultPlatformFee(): Promise<number> {
    // For now, return a default value - could be enhanced to read from contract
    return 250 // 2.5% default platform fee
  }

  /**
   * Estimate total cost with platform fee
   */
  estimateTotalCost(basePrice: bigint, quantity: number, platformFeeBps?: number): {
    baseTotal: bigint
    platformFee: bigint
    grandTotal: bigint
  } {
    const baseTotal = basePrice * BigInt(quantity)
    const platformFee = platformFeeBps ? this.calculatePlatformFee(baseTotal, platformFeeBps) : 0n
    const grandTotal = baseTotal + platformFee

    return {
      baseTotal,
      platformFee,
      grandTotal,
    }
  }

  /**
   * Check if a platform fee rate is reasonable
   */
  isReasonableFeeRate(feeBps: number): boolean {
    // Consider fees between 0.5% and 5% as reasonable
    return feeBps >= 50 && feeBps <= 500
  }
}