projet_gestion_commande/backend/gestion/handlers/parrain.go

package handlers

import (
	"gestion/db"
	"gestion/utils"
	"log"
	"net/http"

	"github.com/gin-gonic/gin"
)

func SetClientParrainAdmin(c *gin.Context) {
	database := c.MustGet("database").(*db.Database)
	targetUsername := c.Param("username")

	var req struct {
		Parrain string `json:"parrain" binding:"required"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Champ parrain requis"})
		return
	}

	if req.Parrain == targetUsername {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Un client ne peut pas être son propre parrain"})
		return
	}

	parrain, err := database.GetClientByUsername(req.Parrain)
	if err != nil || parrain == nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Parrain introuvable"})
		return
	}

	existing, err := database.GetClientParrain(targetUsername)
	if err != nil {
		utils.ServerErr(c, "Erreur vérification parrain", err)
		return
	}
	if existing != "" {
		c.JSON(http.StatusConflict, gin.H{"error": "Ce client a déjà un parrain", "parrain": existing})
		return
	}

	settings, _ := database.GetSettings()
	creditAmount := 0.0
	if settings.ReferralEnabled && settings.ReferralAmount > 0 {
		creditAmount = settings.ReferralAmount
	}

	if err := database.SetClientParrainAndCredit(targetUsername, req.Parrain, creditAmount); err != nil {
		utils.ServerErr(c, "Erreur enregistrement parrain", err)
		return
	}
	log.Printf("✅ [PARRAIN] %s parrainé par %s → +%.2f€ crédité", targetUsername, req.Parrain, creditAmount)

	c.JSON(http.StatusOK, gin.H{
		"message":         "Parrain enregistré",
		"client":          targetUsername,
		"parrain":         req.Parrain,
		"amount_credited": creditAmount,
	})
}

// GetMyParrainInfo — GET /api/v1/parrain (client authentifié)
// Retourne le parrain du client + ses filleuls + son solde parrainage.
func GetMyParrainInfo(c *gin.Context) {
	database := c.MustGet("database").(*db.Database)

	username, exists := c.Get("username")
	if !exists {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Utilisateur non authentifié"})
		return
	}
	clientUsername := username.(string)

	settings, _ := database.GetSettings()

	parrain, err := database.GetClientParrain(clientUsername)
	if err != nil {
		utils.ServerErr(c, "Erreur récupération parrain", err)
		return
	}

	filleuls, err := database.GetClientsByParrain(clientUsername)
	if err != nil {
		utils.ServerErr(c, "Erreur récupération filleuls", err)
		return
	}

	balance, err := database.GetClientReferralBalance(clientUsername)
	if err != nil {
		balance = 0
	}

	filleulNames := make([]string, 0, len(filleuls))
	for _, f := range filleuls {
		filleulNames = append(filleulNames, f.Username)
	}

	c.JSON(http.StatusOK, gin.H{
		"parrain":          parrain,
		"filleuls":         filleulNames,
		"filleul_count":    len(filleulNames),
		"referral_balance": balance,
		"referral_enabled": settings.ReferralEnabled,
		"referral_amount":  settings.ReferralAmount,
	})
}

// GetClientParrainAdmin — GET /api/v2/admin/protected/client/:username/parrain (admin)
// Retourne les infos parrainage d'un client spécifique.
func GetClientParrainAdmin(c *gin.Context) {
	database := c.MustGet("database").(*db.Database)
	targetUsername := c.Param("username")

	parrain, err := database.GetClientParrain(targetUsername)
	if err != nil {
		utils.ServerErr(c, "Erreur récupération parrain", err)
		return
	}

	filleuls, err := database.GetClientsByParrain(targetUsername)
	if err != nil {
		utils.ServerErr(c, "Erreur récupération filleuls", err)
		return
	}

	balance, _ := database.GetClientReferralBalance(targetUsername)

	filleulNames := make([]string, 0, len(filleuls))
	for _, f := range filleuls {
		filleulNames = append(filleulNames, f.Username)
	}

	c.JSON(http.StatusOK, gin.H{
		"username":         targetUsername,
		"parrain":          parrain,
		"filleuls":         filleulNames,
		"filleul_count":    len(filleulNames),
		"referral_balance": balance,
	})
}

// GetParrainStatsAdmin — GET /api/v2/admin/protected/parrain/stats (admin)
// Retourne la liste de tous les parrains avec leur nombre de filleuls et leur solde.
func GetParrainStatsAdmin(c *gin.Context) {
	database := c.MustGet("database").(*db.Database)

	stats, err := database.GetParrainStats()
	if err != nil {
		utils.ServerErr(c, "Erreur récupération stats parrainage", err)
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"parrains": stats,
		"total":    len(stats),
	})
}