package plugins

import (
	"encoding/json"
	"fmt"
	"math"
	"strings"

	"bugulma/backend/internal/domain"
	"bugulma/backend/internal/matching/engine"
)

// BiowastePlugin implements resource-specific matching logic for biowaste resources
type BiowastePlugin struct {
	config *BiowastePluginConfig
}

// BiowastePluginConfig contains configuration for the biowaste plugin
type BiowastePluginConfig struct {
	// Contamination limits
	MaxContaminantPct    float64 `json:"max_contaminant_pct"`
	ContaminationPenalty float64 `json:"contamination_penalty"`

	// Moisture content requirements
	MinMoisturePct          float64 `json:"min_moisture_pct"`
	MaxMoisturePct          float64 `json:"max_moisture_pct"`
	MoistureMismatchPenalty float64 `json:"moisture_mismatch_penalty"`

	// Biodegradability requirements
	MinBiodegradabilityPct float64 `json:"min_biodegradability_pct"`
	BiodegradabilityBonus  float64 `json:"biodegradability_bonus"`

	// Regulatory requirements
	RequiredCertifications []string `json:"required_certifications"`
	CertificationBonus     float64  `json:"certification_bonus"`

	// Economic factors
	WasteDisposalSavings   float64 `json:"waste_disposal_savings"` // €/tonne saved by avoiding landfill
	TransportCostPerKm     float64 `json:"transport_cost_per_km"`
	ProcessingCostPerTonne float64 `json:"processing_cost_per_tonne"`

	// Distance constraints
	MaxTransportDistance  float64 `json:"max_transport_distance"`
	DistancePenaltyFactor float64 `json:"distance_penalty_factor"`

	// Temporal constraints
	ShelfLifeDays     int     `json:"shelf_life_days"`
	StorageCostPerDay float64 `json:"storage_cost_per_day"`
}

// DefaultBiowastePluginConfig returns default configuration for biowaste plugin
func DefaultBiowastePluginConfig() *BiowastePluginConfig {
	return &BiowastePluginConfig{
		MaxContaminantPct:       5.0,
		ContaminationPenalty:    0.3,
		MinMoisturePct:          40.0,
		MaxMoisturePct:          80.0,
		MoistureMismatchPenalty: 0.15,
		MinBiodegradabilityPct:  70.0,
		BiodegradabilityBonus:   0.1,
		RequiredCertifications:  []string{"ISO 14001", "HACCP"},
		CertificationBonus:      0.1,
		WasteDisposalSavings:    50.0,  // €50/tonne landfill savings
		TransportCostPerKm:      0.5,   // €0.50/tonne/km
		ProcessingCostPerTonne:  20.0,  // €20/tonne processing
		MaxTransportDistance:    100.0, // 100km max for biowaste
		DistancePenaltyFactor:   0.01,
		ShelfLifeDays:           7,   // Biowaste degrades quickly
		StorageCostPerDay:       2.0, // €2/tonne/day storage
	}
}

// NewBiowastePlugin creates a new biowaste resource plugin
func NewBiowastePlugin(config *BiowastePluginConfig) *BiowastePlugin {
	if config == nil {
		config = DefaultBiowastePluginConfig()
	}
	return &BiowastePlugin{
		config: config,
	}
}

// Name returns the plugin name
func (bp *BiowastePlugin) Name() string {
	return "biowaste_plugin"
}

// ResourceType returns the resource type this plugin handles
func (bp *BiowastePlugin) ResourceType() domain.ResourceType {
	return domain.TypeBiowaste
}

// SupportsQualityCheck returns true as biowaste plugin provides quality checks
func (bp *BiowastePlugin) SupportsQualityCheck() bool {
	return true
}

// SupportsEconomicCalculation returns true as biowaste plugin provides economic calculations
func (bp *BiowastePlugin) SupportsEconomicCalculation() bool {
	return true
}

// SupportsTemporalCheck returns true as biowaste plugin provides temporal checks
func (bp *BiowastePlugin) SupportsTemporalCheck() bool {
	return true
}

// CheckQualityCompatibility performs biowaste-specific quality compatibility assessment
func (bp *BiowastePlugin) CheckQualityCompatibility(source, target *domain.ResourceFlow) (float64, error) {
	var sourceQuality, targetQuality domain.Quality

	if err := json.Unmarshal(source.Quality, &sourceQuality); err != nil {
		return 0, fmt.Errorf("failed to unmarshal source quality: %w", err)
	}
	if err := json.Unmarshal(target.Quality, &targetQuality); err != nil {
		return 0, fmt.Errorf("failed to unmarshal target quality: %w", err)
	}

	score := 1.0
	var issues []string

	// Contamination check (critical for biowaste)
	if sourceQuality.PurityPct != nil {
		contaminationPct := 100.0 - *sourceQuality.PurityPct // Contamination = 100 - purity
		if contaminationPct > bp.config.MaxContaminantPct {
			return 0, fmt.Errorf("contamination level %.1f%% exceeds maximum %.1f%%",
				contaminationPct, bp.config.MaxContaminantPct)
		}
		score -= (contaminationPct / 100.0) * bp.config.ContaminationPenalty
		if contaminationPct > bp.config.MaxContaminantPct/2 {
			issues = append(issues, fmt.Sprintf("High contamination: %.1f%%", contaminationPct))
		}
	}

	// Moisture content compatibility
	if sourceQuality.MoisturePct != nil {
		moisture := *sourceQuality.MoisturePct
		if moisture < bp.config.MinMoisturePct {
			score -= bp.config.MoistureMismatchPenalty
			issues = append(issues, fmt.Sprintf("Low moisture: %.1f%% (min %.1f%%)", moisture, bp.config.MinMoisturePct))
		} else if moisture > bp.config.MaxMoisturePct {
			score -= bp.config.MoistureMismatchPenalty
			issues = append(issues, fmt.Sprintf("High moisture: %.1f%% (max %.1f%%)", moisture, bp.config.MaxMoisturePct))
		}
	}

	// Biodegradability check
	if sourceQuality.Composition != "" {
		// Simple check for biodegradability keywords
		composition := strings.ToLower(sourceQuality.Composition)
		biodegradable := strings.Contains(composition, "organic") ||
			strings.Contains(composition, "biodegradable") ||
			strings.Contains(composition, "food waste") ||
			strings.Contains(composition, "green waste")

		if biodegradable {
			score += bp.config.BiodegradabilityBonus
		} else {
			score -= 0.2 // Penalty for non-biodegradable waste
			issues = append(issues, "Composition may not be fully biodegradable")
		}
	}

	// Certification compatibility
	if len(sourceQuality.Certifications) > 0 {
		matchingCerts := 0
		for _, required := range bp.config.RequiredCertifications {
			for _, has := range sourceQuality.Certifications {
				if strings.Contains(has, required) {
					matchingCerts++
					break
				}
			}
		}
		if matchingCerts > 0 {
			score += bp.config.CertificationBonus
		}
	}

	// Particle size consideration for processing
	if sourceQuality.ParticleSizeMicron != nil {
		size := *sourceQuality.ParticleSizeMicron
		if size > 50000 { // Very large particles
			score -= 0.05
			issues = append(issues, "Large particle size may require additional processing")
		}
	}

	if len(issues) > 0 && score < 0.7 {
		return score, fmt.Errorf("quality issues: %s", strings.Join(issues, "; "))
	}

	return math.Max(0, math.Min(1, score)), nil
}

// CalculateEconomicImpact performs biowaste-specific economic impact calculation
func (bp *BiowastePlugin) CalculateEconomicImpact(source, target *domain.ResourceFlow, distance float64) (float64, error) {
	var sourceEcon, targetEcon domain.EconomicData
	var sourceQty domain.Quantity

	if err := json.Unmarshal(source.EconomicData, &sourceEcon); err != nil {
		return 0, fmt.Errorf("failed to unmarshal source economic data: %w", err)
	}
	if err := json.Unmarshal(target.EconomicData, &targetEcon); err != nil {
		return 0, fmt.Errorf("failed to unmarshal target economic data: %w", err)
	}
	if err := json.Unmarshal(source.Quantity, &sourceQty); err != nil {
		return 0, fmt.Errorf("failed to unmarshal source quantity: %w", err)
	}

	// Base economic calculation for biowaste
	// Savings = waste disposal cost avoided + value from reuse - transport - processing

	// Waste disposal savings (avoiding landfill/incineration)
	disposalSavings := bp.config.WasteDisposalSavings * sourceQty.Amount

	// Transport costs
	transportCost := distance * bp.config.TransportCostPerKm * sourceQty.Amount

	// Processing costs for the receiving facility
	processingCost := bp.config.ProcessingCostPerTonne * sourceQty.Amount

	// Value from reuse (what the target pays for the waste as input)
	reuseValue := targetEcon.CostIn * sourceQty.Amount

	// Storage costs due to short shelf life
	storageDays := float64(bp.config.ShelfLifeDays)
	storageCost := bp.config.StorageCostPerDay * sourceQty.Amount * storageDays

	// Distance penalty for biowaste degradation
	distancePenalty := distance * bp.config.DistancePenaltyFactor * sourceQty.Amount

	// Annual volume calculation
	annualVolume := sourceQty.Amount
	switch sourceQty.TemporalUnit {
	case domain.UnitPerDay:
		annualVolume *= 365
	case domain.UnitPerWeek:
		annualVolume *= 52
	case domain.UnitPerMonth:
		annualVolume *= 12
	}

	// Total annual economic impact
	totalAnnualSavings := (disposalSavings + reuseValue - transportCost - processingCost - storageCost - distancePenalty) * annualVolume

	// Distance constraint check
	if distance > bp.config.MaxTransportDistance {
		return totalAnnualSavings, fmt.Errorf("transport distance %.1fkm exceeds maximum %.1fkm for biowaste",
			distance, bp.config.MaxTransportDistance)
	}

	// Minimum viability check
	if totalAnnualSavings < 1000.0 { // €1,000 minimum annual savings
		return totalAnnualSavings, fmt.Errorf("insufficient economic viability: annual savings €%.0f below minimum €1,000",
			totalAnnualSavings)
	}

	return totalAnnualSavings, nil
}

// CheckTemporalCompatibility performs biowaste-specific temporal compatibility assessment
func (bp *BiowastePlugin) CheckTemporalCompatibility(source, target *domain.ResourceFlow) (float64, error) {
	var sourceTime, targetTime domain.TimeProfile

	if err := json.Unmarshal(source.TimeProfile, &sourceTime); err != nil {
		return 0, fmt.Errorf("failed to unmarshal source time profile: %w", err)
	}
	if err := json.Unmarshal(target.TimeProfile, &targetTime); err != nil {
		return 0, fmt.Errorf("failed to unmarshal target time profile: %w", err)
	}

	score := 1.0

	// Biowaste has short shelf life - temporal alignment is critical
	sourceHours := bp.calculateWeeklyHours(sourceTime.Availability)
	targetHours := bp.calculateWeeklyHours(targetTime.Availability)
	overlapHours := math.Min(sourceHours, targetHours)

	// Biowaste requires more frequent collection/processing
	minOverlapHours := 40.0 // 40 hours/week minimum for biowaste
	if overlapHours < minOverlapHours {
		return 0, fmt.Errorf("insufficient temporal overlap: %.0f hours/week < minimum %.0f hours/week for biowaste",
			overlapHours, minOverlapHours)
	}

	overlapScore := overlapHours / 168.0 // 168 hours in a week
	score *= overlapScore

	// Seasonality consideration (food waste peaks in certain seasons)
	if len(sourceTime.Seasonality) > 0 && len(targetTime.Seasonality) > 0 {
		seasonOverlap := bp.calculateSeasonalOverlap(sourceTime.Seasonality, targetTime.Seasonality)
		score *= (0.8 + 0.2*seasonOverlap) // 80-100% based on seasonal alignment
	}

	// Predictability is crucial for biowaste logistics
	sourcePredictability := 0.5
	targetPredictability := 0.5

	if sourceTime.PredictabilityScore != nil {
		sourcePredictability = *sourceTime.PredictabilityScore
	}
	if targetTime.PredictabilityScore != nil {
		targetPredictability = *targetTime.PredictabilityScore
	}

	// Biowaste requires high predictability
	minPredictability := 0.7
	avgPredictability := (sourcePredictability + targetPredictability) / 2
	if avgPredictability < minPredictability {
		score *= 0.5 // Significant penalty for unpredictable supply
	} else {
		score *= avgPredictability
	}

	// Lead time consideration
	requiredLeadTime := 24.0 // 24 hours for biowaste
	if sourceTime.LeadTimeDays != nil && targetTime.LeadTimeDays != nil {
		actualLeadTime := math.Max(float64(*sourceTime.LeadTimeDays), float64(*targetTime.LeadTimeDays)) * 24
		if actualLeadTime > requiredLeadTime {
			score *= 0.9 // Minor penalty for longer lead times
		}
	}

	return math.Max(0, math.Min(1, score)), nil
}

// ValidateCandidate performs biowaste-specific candidate validation
func (bp *BiowastePlugin) ValidateCandidate(candidate *engine.Candidate) (bool, string) {
	// Biowaste-specific validation rules

	// 1. Distance constraint
	if candidate.DistanceKm > bp.config.MaxTransportDistance {
		return false, fmt.Sprintf("Transport distance %.1fkm exceeds maximum %.1fkm for biowaste",
			candidate.DistanceKm, bp.config.MaxTransportDistance)
	}

	// 2. Minimum annual savings
	if candidate.EstimatedAnnualSavings < 2000.0 { // Higher threshold for biowaste
		return false, "Annual savings below €2,000 threshold for biowaste matching"
	}

	// 3. Quality score threshold (higher for biowaste due to contamination risks)
	if candidate.QualityScore < 0.7 {
		return false, "Quality score below 0.7 threshold for biowaste matching"
	}

	// 4. Temporal score (critical for perishable waste)
	if candidate.TemporalScore < 0.6 {
		return false, "Temporal compatibility below 0.6 threshold for biowaste matching"
	}

	return true, "Biowaste matching candidate validation passed"
}

// calculateWeeklyHours calculates total available hours per week from availability map
func (bp *BiowastePlugin) calculateWeeklyHours(availability map[string]domain.TimeRange) float64 {
	totalHours := 0.0

	for _, timeRange := range availability {
		// Simple calculation - in production this would parse time ranges properly
		hours := 8.0 // Default 8 hours per day
		totalHours += hours
		_ = timeRange // Mark as used to avoid linter warning
	}

	return totalHours
}

// calculateSeasonalOverlap calculates overlap between seasonality arrays
func (bp *BiowastePlugin) calculateSeasonalOverlap(source, target []string) float64 {
	if len(source) == 0 || len(target) == 0 {
		return 0
	}

	overlap := 0
	for _, s := range source {
		for _, t := range target {
			if s == t {
				overlap++
				break
			}
		}
	}

	return float64(overlap) / math.Max(float64(len(source)), float64(len(target)))
}