hash-wallet/cw_evm/lib/utils/evm_chain_utils.dart

import "package:cw_evm/evm_chain_transaction_priority.dart";
import "package:web3dart/web3dart.dart" show EtherAmount, EtherUnit;

/// Utility class for chain-specific EVM chain operations
class EVMChainUtils {
  static int getTotalPriorityFee(EVMChainTransactionPriority priority, int chainId) => switch (chainId) {
      1 => _ethereumPriorityFee(priority),
      137 => _polygonPriorityFee(priority),
      8453 => _basePriorityFee(priority),
      56 => _ethereumPriorityFee(priority),
      42161 => 0, // Arbitrum doesn't use priority fees
      _ => _ethereumPriorityFee(priority),
    };

  static bool hasPriorityFee(int chainId) => switch (chainId) {
      42161 => false, // Arbitrum doesn't use priority fees
      _ => true,
    };

  static int computeBufferedMaxFeePerGasWei({
    required int? gasBaseFee,
    required int gasPrice,
    required int priorityFeeWei,
    required bool chainHasPriorityFee,
  }) {
    if (gasBaseFee != null && gasBaseFee > 0) {
      final baseFeeWithPriority = gasBaseFee + priorityFeeWei;
      final bufferMultiplier = chainHasPriorityFee ? 115 : 105;
      final bufferPercent = (baseFeeWithPriority * bufferMultiplier) ~/ 100;
      final bufferMin = baseFeeWithPriority + (baseFeeWithPriority ~/ 100);
      return bufferPercent > bufferMin ? bufferPercent : bufferMin;
    }
    return gasPrice + priorityFeeWei;
  }

  static String getTransactionHistoryFileName(int chainId) => switch (chainId) {
      1 => "transactions.json", // Ethereum
      137 => "polygon_transactions.json",
      8453 => "base_transactions.json",
      42161 => "arbitrum_transactions.json",
      56 => "bsc_transactions.json",
      _ => "transactions_$chainId.json", // Generic format for other chains
    };

  /// Get scan provider preference key for a wallet type
  static String getScanProviderPreferenceKey(int chainId) => switch (chainId) {
      1 => "use_etherscan",
      137 => "use_polygonscan",
      8453 => "use_base_scan",
      42161 => "use_arbitrum_scan",
      56 => "use_bscscan",
      _ => "use_etherscan",
    };

  static String getDefaultTokenTag(int chainId) => switch (chainId) {
      1 => "ETH",
      137 => "POL",
      8453 => "BASE",
      42161 => "ARB",
      56 => "BSC",
      _ => "ETH",
    };

  static String getFeeCurrency(int chainId) => switch (chainId) {
      1 => "ETH",
      137 => "POL",
      8453 => "ETH",
      42161 => "ETH",
      56 => "BNB",
      _ => "ETH",
    };

  static String getDefaultTokenSymbol(int chainId) => switch (chainId) {
      1 => "ETH",
      137 => "POL",
      8453 => "BASE",
      42161 => "ARBITRUM",
      56 => "BSC",
      _ => "ETH",
    };

  static int _ethereumPriorityFee(EVMChainTransactionPriority priority) => EtherAmount.fromInt(EtherUnit.gwei, priority.tip).getInWei.toInt();

  // Polygon priority fee calculation (minimum 25 gwei + additional based on priority)
  static int _polygonPriorityFee(EVMChainTransactionPriority priority) {
    const int minPriorityFee = 25;
    final minPriorityFeeWei = EtherAmount.fromInt(EtherUnit.gwei, minPriorityFee).getInWei.toInt();

    final int additionalPriorityFee = switch (priority) {
      EVMChainTransactionPriority.slow => 0,
      EVMChainTransactionPriority.medium =>
        EtherAmount.fromInt(EtherUnit.gwei, 15).getInWei.toInt(),
      EVMChainTransactionPriority.fast => EtherAmount.fromInt(EtherUnit.gwei, 35).getInWei.toInt(),
      _ => 0,
    };

    return minPriorityFeeWei + additionalPriorityFee;
  }

  static int _basePriorityFee(EVMChainTransactionPriority priority) => switch (priority) {
      EVMChainTransactionPriority.fast => EtherAmount.fromInt(EtherUnit.mwei, 5).getInWei.toInt(),
      EVMChainTransactionPriority.medium => EtherAmount.fromInt(EtherUnit.mwei, 3).getInWei.toInt(),
      EVMChainTransactionPriority.slow => EtherAmount.fromInt(EtherUnit.mwei, 1).getInWei.toInt(),
      _ => EtherAmount.fromInt(EtherUnit.mwei, 1).getInWei.toInt(),
    };
}