// Package validation defines the validation interface for swap events and pools
package validation

import (
	"context"
	"math/big"

	"github.com/ethereum/go-ethereum/common"

	"github.com/your-org/mev-bot/pkg/types"
)

// Validator defines the interface for validating swap events and pools
type Validator interface {
	// ValidateSwapEvent validates a swap event
	ValidateSwapEvent(ctx context.Context, event *types.SwapEvent) error

	// ValidatePoolInfo validates pool information
	ValidatePoolInfo(ctx context.Context, pool *types.PoolInfo) error

	// FilterValid filters a slice of swap events, returning only valid ones
	FilterValid(ctx context.Context, events []*types.SwapEvent) []*types.SwapEvent

	// GetValidationRules returns the current validation rules
	GetValidationRules() *ValidationRules
}

// ValidationRules defines the rules for validation
type ValidationRules struct {
	// Reject zero addresses
	RejectZeroAddresses bool

	// Reject zero amounts
	RejectZeroAmounts bool

	// Minimum amount threshold (in wei, scaled to 18 decimals)
	MinAmount *big.Int

	// Maximum amount threshold (in wei, scaled to 18 decimals)
	MaxAmount *big.Int

	// Allowed protocols (empty = all allowed)
	AllowedProtocols map[types.ProtocolType]bool

	// Reject events from blacklisted pools
	BlacklistedPools map[common.Address]bool

	// Reject events from blacklisted tokens
	BlacklistedTokens map[common.Address]bool

	// Validate decimal precision
	ValidateDecimals bool

	// Maximum acceptable slippage (in basis points, e.g. 50 = 0.5%)
	MaxSlippageBps uint32
}

// DefaultValidationRules returns the default validation rules
func DefaultValidationRules() *ValidationRules {
	return &ValidationRules{
		RejectZeroAddresses:  true,
		RejectZeroAmounts:    true,
		MinAmount:            big.NewInt(1000),           // 0.000000000000001 ETH minimum
		MaxAmount:            new(big.Int).Exp(big.NewInt(10), big.NewInt(30), nil), // 1 trillion tokens max
		AllowedProtocols:     make(map[types.ProtocolType]bool),
		BlacklistedPools:     make(map[common.Address]bool),
		BlacklistedTokens:    make(map[common.Address]bool),
		ValidateDecimals:     true,
		MaxSlippageBps:       50,  // 0.5% max slippage
	}
}