package financial

// RiskAssessorImpl implements RiskAssessor interface
type RiskAssessorImpl struct {
	config *Config
}

// NewRiskAssessor creates a new risk assessor
func NewRiskAssessor(config *Config) RiskAssessor {
	return &RiskAssessorImpl{config: config}
}

// AssessRisk performs comprehensive risk assessment based on resource flow data
func (ra *RiskAssessorImpl) AssessRisk(data *ResourceFlowData) *RiskAssessment {
	risk := &RiskAssessment{}

	// Technical risk based on distance and resource type
	risk.TechnicalRisk = ra.calculateTechnicalRisk(data.DistanceKm, data.ResourceType)

	// Regulatory risk based on resource type
	risk.RegulatoryRisk = ra.calculateRegulatoryRisk(data.ResourceType)

	// Market risk based on volume stability
	risk.MarketRisk = ra.calculateMarketRisk(data.AnnualVolume)

	// Counterparty risk (simplified - would need more business logic)
	risk.CounterpartyRisk = 0.3 // Default medium risk

	// Calculate overall risk as weighted average
	risk.OverallRisk = (risk.TechnicalRisk*0.4 + risk.RegulatoryRisk*0.3 + risk.MarketRisk*0.2 + risk.CounterpartyRisk*0.1)

	// Determine risk level
	risk.RiskLevel = ra.calculateRiskLevel(risk.OverallRisk)

	// Identify primary risk factors
	risk.PrimaryRisks = ra.identifyPrimaryRiskFactors(data, risk)

	return risk
}

// calculateTechnicalRisk assesses technical implementation risk
func (ra *RiskAssessorImpl) calculateTechnicalRisk(distanceKm float64, resourceType string) float64 {
	risk := 0.0

	// Distance risk
	if distanceKm > 50 {
		risk += 0.3
	} else if distanceKm > 20 {
		risk += 0.1
	}

	// Resource type risk
	switch resourceType {
	case "heat", "steam", "cooling":
		risk += 0.2 // Infrastructure complexity
	case "biowaste", "CO2":
		risk += 0.4 // Handling and safety requirements
	case "materials":
		risk += 0.1 // Relatively straightforward
	}

	return risk
}

// calculateRegulatoryRisk assesses regulatory compliance risk
func (ra *RiskAssessorImpl) calculateRegulatoryRisk(resourceType string) float64 {
	switch resourceType {
	case "biowaste":
		return 0.6 // High regulatory requirements
	case "CO2", "water":
		return 0.4 // Medium regulatory requirements
	case "heat", "steam":
		return 0.2 // Lower regulatory requirements
	default:
		return 0.3
	}
}

// calculateMarketRisk assesses market and volume stability risk
func (ra *RiskAssessorImpl) calculateMarketRisk(annualVolume float64) float64 {
	if annualVolume < 100 {
		return 0.7 // High risk for low volume
	} else if annualVolume < 1000 {
		return 0.4 // Medium risk
	}
	return 0.1 // Low risk for high volume
}

// calculateRiskLevel determines risk level from overall risk score
func (ra *RiskAssessorImpl) calculateRiskLevel(overallRisk float64) string {
	switch {
	case overallRisk < ra.config.RiskThresholds.Low:
		return "low"
	case overallRisk < ra.config.RiskThresholds.Medium:
		return "medium"
	case overallRisk < ra.config.RiskThresholds.High:
		return "high"
	default:
		return "critical"
	}
}

// identifyPrimaryRiskFactors identifies the main risk factors contributing to overall risk
func (ra *RiskAssessorImpl) identifyPrimaryRiskFactors(data *ResourceFlowData, risk *RiskAssessment) []string {
	var primaryRisks []string

	// Technical risk factors
	if data.DistanceKm > 100 {
		primaryRisks = append(primaryRisks, "technical_failure")
	}
	if data.ResourceType == "biowaste" || data.ResourceType == "CO2" {
		primaryRisks = append(primaryRisks, "technical_failure")
	}

	// Regulatory risk factors
	if data.ResourceType == "biowaste" {
		primaryRisks = append(primaryRisks, "regulatory_changes")
	}

	// Market risk factors
	if data.AnnualVolume < 500 {
		primaryRisks = append(primaryRisks, "market_volatility")
	}

	// Distance-related market risk
	if data.DistanceKm > 200 {
		primaryRisks = append(primaryRisks, "market_volatility")
	}

	return primaryRisks
}