// ============================================
// db/cancel_sanctions_db.go
// GESTION DES SANCTIONS ÉVOLUTIVES
// ============================================

package db

import (
	"fmt"
	"gestion/models"
	"log"
	"sort"

	"gorm.io/gorm"
)

// GetClientCancellationsCount récupère le nombre d'annulations tardives d'un client
func (d *Database) GetClientCancellationsCount(username string) (int, error) {
	var result struct {
		Count int `gorm:"column:count"`
	}
	err := d.GDB.Table("clients").Select("COALESCE(cancellations_count, 0) as count").Where("username = ?", username).Scan(&result).Error
	if err != nil {
		log.Printf("❌ [GetCancellationsCount] Erreur: %v", err)
		return 0, fmt.Errorf("erreur récupération compteur: %w", err)
	}
	return result.Count, nil
}

// IncrementClientCancellationsCount incrémente le compteur d'annulations
func (d *Database) IncrementClientCancellationsCount(username string) error {
	result := d.GDB.Model(&models.Client{}).Where("username = ?", username).Updates(map[string]any{
		"cancellations_count": gorm.Expr("COALESCE(cancellations_count, 0) + 1"),
	})
	if result.Error != nil {
		log.Printf("❌ [IncrementCancellations] Erreur: %v", result.Error)
		return fmt.Errorf("erreur incrémentation: %w", result.Error)
	}
	if result.RowsAffected == 0 {
		return fmt.Errorf("client non trouvé")
	}

	cacheKey := fmt.Sprintf("client:%s", username)
	Redis.Del(RedisCtx, cacheKey)

	return nil
}

// penaltyForCount retourne le montant du palier applicable pour un nombre d'annulations donné
func penaltyForCount(count int, tiers []models.PenaltyTier) int {
	if len(tiers) == 0 {
		return 0
	}
	sorted := make([]models.PenaltyTier, len(tiers))
	copy(sorted, tiers)
	sort.Slice(sorted, func(i, j int) bool {
		return sorted[i].MinCancel > sorted[j].MinCancel
	})
	for _, t := range sorted {
		if count >= t.MinCancel {
			return t.Amount
		}
	}
	return sorted[len(sorted)-1].Amount
}

// CalculateCancellationPenalty calcule la pénalité selon l'historique et le barème configuré
func (d *Database) CalculateCancellationPenalty(username string) (int, error) {
	count, err := d.GetClientCancellationsCount(username)
	if err != nil {
		return 0, err
	}

	settings, err := d.GetSettings()
	if err != nil {
		log.Printf("⚠️ [CalculatePenalty] Impossible de charger les settings, barème par défaut: %v", err)
		settings = DefaultSettings()
	}

	penalty := penaltyForCount(count, settings.PenaltyTiers)

	log.Printf("💰 [CalculatePenalty] Client %s - Annulations: %d → Pénalité: %d points",
		username, count, penalty)

	return penalty, nil
}

// ApplyCancellationPenalty applique une pénalité et incrémente le compteur d'annulations
func (d *Database) ApplyCancellationPenalty(username string) (int, error) {
	penalty, err := d.CalculateCancellationPenalty(username)
	if err != nil {
		return 0, err
	}

	log.Printf("⚠️  [ApplyCancellationPenalty] Client %s - Pénalité calculée: %d points", username, penalty)

	if err := d.IncrementClientCancellationsCount(username); err != nil {
		return 0, err
	}

	result := d.GDB.Model(&models.Client{}).Where("username = ?", username).Update("amende", float64(penalty))
	if result.Error != nil {
		log.Printf("❌ [ApplyCancellationPenalty] Erreur UPDATE: %v", result.Error)
		return 0, fmt.Errorf("erreur application pénalité: %w", result.Error)
	}
	if result.RowsAffected == 0 {
		return 0, fmt.Errorf("client non trouvé")
	}

	log.Printf("✅ [ApplyCancellationPenalty] Amende %d appliquée à %s", penalty, username)

	cacheKey := fmt.Sprintf("client:%s", username)
	Redis.Del(RedisCtx, cacheKey)

	return penalty, nil
}

// GetClientCancellationHistory récupère l'historique d'annulations d'un client
func (d *Database) GetClientCancellationHistory(username string) (map[string]any, error) {
	nextPenalty, err := d.CalculateCancellationPenalty(username)
	if err != nil {
		return nil, err
	}

	count, err := d.GetClientCancellationsCount(username)
	if err != nil {
		return nil, err
	}

	settings, _ := d.GetSettings()

	client, err := d.GetClientByUsername(username)
	var currentAmende float64
	if err == nil {
		currentAmende = client.Amende
	}

	return map[string]any{
		"cancellations_count": count,
		"current_amende":      currentAmende,
		"next_penalty":        nextPenalty,
		"penalty_tiers":       settings.PenaltyTiers,
		"warning":             "Une amende sera appliquée lors de la prochaine annulation tardive",
	}, nil
}