veza/veza-backend-api/internal/handlers/playlist_handler.go

package handlers

import (
	"net/http"
	"strconv"

	"veza-backend-api/internal/models"
	"veza-backend-api/internal/services"
	"veza-backend-api/internal/validators"

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

// PlaylistHandler gère les opérations sur les playlists
type PlaylistHandler struct {
	playlistService          *services.PlaylistService
	playlistAnalyticsService *services.PlaylistAnalyticsService
	playlistFollowService    *services.PlaylistFollowService
}

// NewPlaylistHandler crée un nouveau handler de playlists
func NewPlaylistHandler(playlistService *services.PlaylistService) *PlaylistHandler {
	return &PlaylistHandler{playlistService: playlistService}
}

// SetPlaylistAnalyticsService définit le service d'analytics de playlist
// T0491: Create Playlist Analytics Backend
func (h *PlaylistHandler) SetPlaylistAnalyticsService(analyticsService *services.PlaylistAnalyticsService) {
	h.playlistAnalyticsService = analyticsService
}

// SetPlaylistFollowService définit le service de follow de playlist
// T0498: Create Playlist Recommendations
func (h *PlaylistHandler) SetPlaylistFollowService(followService *services.PlaylistFollowService) {
	h.playlistFollowService = followService
}

// CreatePlaylistRequest représente la requête pour créer une playlist
type CreatePlaylistRequest struct {
	Title       string `json:"title" binding:"required,min=1,max=200"`
	Description string `json:"description,omitempty"`
	IsPublic    bool   `json:"is_public"`
}

// UpdatePlaylistRequest représente la requête pour mettre à jour une playlist
type UpdatePlaylistRequest struct {
	Title       *string `json:"title,omitempty" binding:"omitempty,min=1,max=200"`
	Description *string `json:"description,omitempty"`
	IsPublic    *bool   `json:"is_public,omitempty"`
}

// ReorderTracksRequest représente la requête pour réorganiser les tracks
type ReorderTracksRequest struct {
	TrackIDs []uuid.UUID `json:"track_ids" binding:"required,min=1"` // Changed to []uuid.UUID
}

// CreatePlaylist gère la création d'une playlist
// GO-013: Utilise validator centralisé pour validation améliorée
func (h *PlaylistHandler) CreatePlaylist(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	var req CreatePlaylistRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		// GO-013: Utiliser validator pour messages d'erreur plus clairs
		validator := validators.NewValidator()
		if validationErrs := validator.Validate(&req); len(validationErrs) > 0 {
			// Utiliser le format standardisé d'erreur de validation
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "Validation failed",
				"errors": validationErrs,
			})
			return
		}
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	playlist, err := h.playlistService.CreatePlaylist(c.Request.Context(), userID, req.Title, req.Description, req.IsPublic)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusCreated, gin.H{"playlist": playlist})
}

// GetPlaylists gère la récupération des playlists avec pagination
func (h *PlaylistHandler) GetPlaylists(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "20"))

	if page < 1 {
		page = 1
	}
	if limit < 1 {
		limit = 20
	}
	if limit > 100 {
		limit = 100
	}

	// Filtres optionnels
	var filterUserID *uuid.UUID
	if filterUserIDStr := c.Query("user_id"); filterUserIDStr != "" {
		if uid, err := uuid.Parse(filterUserIDStr); err == nil {
			filterUserID = &uid
		}
	}

	// Get current user ID
	var currentUserID *uuid.UUID
	if uidInterface, exists := c.Get("user_id"); exists {
		if uid, ok := uidInterface.(uuid.UUID); ok {
			currentUserID = &uid
		}
	}

	playlists, total, err := h.playlistService.GetPlaylists(c.Request.Context(), currentUserID, filterUserID, page, limit)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"playlists": playlists,
		"total":     total,
		"page":      page,
		"limit":     limit,
	})
}

// GetPlaylist gère la récupération d'une playlist
func (h *PlaylistHandler) GetPlaylist(c *gin.Context) {
	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	var currentUserID *uuid.UUID
	if uidInterface, exists := c.Get("user_id"); exists {
		if uid, ok := uidInterface.(uuid.UUID); ok {
			currentUserID = &uid
		}
	}

	playlist, err := h.playlistService.GetPlaylist(c.Request.Context(), playlistID, currentUserID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"playlist": playlist})
}

// UpdatePlaylist gère la mise à jour d'une playlist
func (h *PlaylistHandler) UpdatePlaylist(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	var req UpdatePlaylistRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		// GO-013: Utiliser validator pour messages d'erreur plus clairs
		validator := validators.NewValidator()
		if validationErrs := validator.Validate(&req); len(validationErrs) > 0 {
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "Validation failed",
				"errors": validationErrs,
			})
			return
		}
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	playlist, err := h.playlistService.UpdatePlaylist(c.Request.Context(), playlistID, userID, req.Title, req.Description, req.IsPublic)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "forbidden" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"playlist": playlist})
}

// DeletePlaylist gère la suppression d'une playlist
func (h *PlaylistHandler) DeletePlaylist(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	if err := h.playlistService.DeletePlaylist(c.Request.Context(), playlistID, userID); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "forbidden" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "playlist deleted"})
}

// AddTrack gère l'ajout d'un track à une playlist
func (h *PlaylistHandler) AddTrack(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// Track IDs are uuid.UUID
	trackID, err := uuid.Parse(c.Param("trackId")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid track id"})
		return
	}

	if err := h.playlistService.AddTrack(c.Request.Context(), playlistID, trackID, userID); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "track not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "track not found"})
			return
		}
		if err.Error() == "track already in playlist" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "track already in playlist"})
			return
		}
		if err.Error() == "forbidden" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "track added to playlist"})
}

// RemoveTrack gère la suppression d'un track d'une playlist
func (h *PlaylistHandler) RemoveTrack(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// Track IDs are uuid.UUID
	trackID, err := uuid.Parse(c.Param("trackId")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid track id"})
		return
	}

	if err := h.playlistService.RemoveTrack(c.Request.Context(), playlistID, trackID, userID); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "track not in playlist" {
			c.JSON(http.StatusNotFound, gin.H{"error": "track not in playlist"})
			return
		}
		if err.Error() == "forbidden" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "track removed from playlist"})
}

// ReorderTracks gère la réorganisation des tracks d'une playlist
func (h *PlaylistHandler) ReorderTracks(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	var req ReorderTracksRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := h.playlistService.ReorderTracks(c.Request.Context(), playlistID, userID, req.TrackIDs); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "some tracks are not in the playlist" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "some tracks are not in the playlist"})
			return
		}
		if err.Error() == "forbidden" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "tracks reordered"})
}

// AddCollaboratorRequest représente la requête pour ajouter un collaborateur
type AddCollaboratorRequest struct {
	UserID     uuid.UUID `json:"user_id" binding:"required"`
	Permission string    `json:"permission" binding:"required,oneof=read write admin"`
}

// UpdateCollaboratorPermissionRequest représente la requête pour mettre à jour la permission d'un collaborateur
type UpdateCollaboratorPermissionRequest struct {
	Permission string `json:"permission" binding:"required,oneof=read write admin"`
}

// AddCollaborator gère l'ajout d'un collaborateur à une playlist
// T0479: POST /api/v1/playlists/:id/collaborators
func (h *PlaylistHandler) AddCollaborator(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	var req AddCollaboratorRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	// Convertir la permission string en PlaylistPermission
	var permission models.PlaylistPermission
	switch req.Permission {
	case "read":
		permission = models.PlaylistPermissionRead
	case "write":
		permission = models.PlaylistPermissionWrite
	case "admin":
		permission = models.PlaylistPermissionAdmin
	default:
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid permission"})
		return
	}

	collaborator, err := h.playlistService.AddCollaborator(c.Request.Context(), playlistID, userID, req.UserID, permission)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "user not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "user not found"})
			return
		}
		if err.Error() == "user is already a collaborator" {
			c.JSON(http.StatusConflict, gin.H{"error": "user is already a collaborator"})
			return
		}
		if err.Error() == "cannot add playlist owner as collaborator" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "cannot add playlist owner as collaborator"})
			return
		}
		if err.Error() == "forbidden: only playlist owner can add collaborators" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusCreated, gin.H{"collaborator": collaborator})
}

// RemoveCollaborator gère la suppression d'un collaborateur d'une playlist
// T0479: DELETE /api/v1/playlists/:id/collaborators/:userId
func (h *PlaylistHandler) RemoveCollaborator(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// User IDs are UUID
	collaboratorUserID, err := uuid.Parse(c.Param("userId"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid user id"})
		return
	}

	if err := h.playlistService.RemoveCollaborator(c.Request.Context(), playlistID, userID, collaboratorUserID); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "collaborator not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "collaborator not found"})
			return
		}
		if err.Error() == "forbidden: only playlist owner can remove collaborators" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "collaborator removed"})
}

// UpdateCollaboratorPermission gère la mise à jour de la permission d'un collaborateur
// T0479: PUT /api/v1/playlists/:id/collaborators/:userId
func (h *PlaylistHandler) UpdateCollaboratorPermission(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// User IDs are UUID
	collaboratorUserID, err := uuid.Parse(c.Param("userId"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid user id"})
		return
	}

	var req UpdateCollaboratorPermissionRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	// Convertir la permission string en PlaylistPermission
	var permission models.PlaylistPermission
	switch req.Permission {
	case "read":
		permission = models.PlaylistPermissionRead
	case "write":
		permission = models.PlaylistPermissionWrite
	case "admin":
		permission = models.PlaylistPermissionAdmin
	default:
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid permission"})
		return
	}

	if err := h.playlistService.UpdateCollaboratorPermission(c.Request.Context(), playlistID, userID, collaboratorUserID, permission); err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "collaborator not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "collaborator not found"})
			return
		}
		if err.Error() == "invalid permission" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "invalid permission"})
			return
		}
		if err.Error() == "forbidden: only playlist owner can update collaborator permissions" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "collaborator permission updated"})
}

// GetCollaborators gère la récupération des collaborateurs d'une playlist
// T0479: GET /api/v1/playlists/:id/collaborators
func (h *PlaylistHandler) GetCollaborators(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	collaborators, err := h.playlistService.GetCollaborators(c.Request.Context(), playlistID, userID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "forbidden: access denied" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"collaborators": collaborators})
}

// CreateShareLink gère la création d'un lien de partage public pour une playlist
// T0488: Create Playlist Public Share Link
func (h *PlaylistHandler) CreateShareLink(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// Créer le lien de partage via le service
	// La vérification des permissions (owner ou admin) est faite dans PlaylistService.CreateShareLink
	shareLink, err := h.playlistService.CreateShareLink(c.Request.Context(), playlistID, userID, nil)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "forbidden: only owner or admin can create share links" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"share_link": shareLink})
}

// FollowPlaylist gère le follow d'une playlist
// T0489: Create Playlist Follow Feature
func (h *PlaylistHandler) FollowPlaylist(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	err = h.playlistService.FollowPlaylist(c.Request.Context(), playlistID, userID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "cannot follow own playlist" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "cannot follow own playlist"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "playlist followed"})
}

// UnfollowPlaylist gère l'unfollow d'une playlist
// T0489: Create Playlist Follow Feature
func (h *PlaylistHandler) UnfollowPlaylist(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	err = h.playlistService.UnfollowPlaylist(c.Request.Context(), playlistID, userID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "playlist unfollowed"})
}

// GetPlaylistStats gère la récupération des statistiques d'une playlist
// T0491: Create Playlist Analytics Backend
func (h *PlaylistHandler) GetPlaylistStats(c *gin.Context) {
	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	// Vérifier que la playlist existe et que l'utilisateur a accès
	var userID *uuid.UUID
	if uidInterface, exists := c.Get("user_id"); exists {
		if uid, ok := uidInterface.(uuid.UUID); ok {
			userID = &uid
		}
	}

	playlist, err := h.playlistService.GetPlaylist(c.Request.Context(), playlistID, userID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	// Vérifier que l'utilisateur a accès (propriétaire, collaborateur ou playlist publique)
	// Use uuid.Nil for comparison if userID is nil
	currentUserID := uuid.Nil
	if userID != nil {
		currentUserID = *userID
	}

	if playlist.UserID != currentUserID && !playlist.IsPublic {
		// Vérifier si l'utilisateur est collaborateur
		if userID != nil {
			hasAccess, err := h.playlistService.CheckPermission(c.Request.Context(), playlistID, *userID, models.PlaylistPermissionRead)
			if err != nil || !hasAccess {
				c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
				return
			}
		} else {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
	}

	// Récupérer les statistiques via le service d'analytics
	if h.playlistAnalyticsService == nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "analytics service not available"})
		return
	}

	stats, err := h.playlistAnalyticsService.GetPlaylistStats(c.Request.Context(), playlistID)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

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

// DuplicatePlaylistRequest représente la requête pour dupliquer une playlist
type DuplicatePlaylistRequest struct {
	NewTitle       string `json:"new_title"`
	NewDescription string `json:"new_description,omitempty"`
	IsPublic       *bool  `json:"is_public,omitempty"`
}

// DuplicatePlaylist gère la duplication d'une playlist
// T0495: Create Playlist Duplicate Feature
func (h *PlaylistHandler) DuplicatePlaylist(c *gin.Context) {
	// Playlist IDs are uuid.UUID
	playlistID, err := uuid.Parse(c.Param("id")) // Changed to uuid.Parse
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid playlist id"})
		return
	}

	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	var req DuplicatePlaylistRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	// Créer le service de duplication
	duplicateService := services.NewPlaylistDuplicateService(h.playlistService, nil)

	// Dupliquer la playlist
	newPlaylist, err := duplicateService.DuplicatePlaylist(
		c.Request.Context(),
		playlistID,
		userID,
		services.DuplicatePlaylistRequest{
			NewTitle:       req.NewTitle,
			NewDescription: req.NewDescription,
			IsPublic:       req.IsPublic,
		},
	)
	if err != nil {
		if err.Error() == "playlist not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": "playlist not found"})
			return
		}
		if err.Error() == "forbidden: you don't have access to this playlist" {
			c.JSON(http.StatusForbidden, gin.H{"error": "forbidden"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message":  "playlist duplicated successfully",
		"playlist": newPlaylist,
	})
}

// SearchPlaylists gère la recherche de playlists
// T0496: Create Playlist Search Backend
func (h *PlaylistHandler) SearchPlaylists(c *gin.Context) {
	// Get current user ID
	var currentUserID *uuid.UUID
	if uidInterface, exists := c.Get("user_id"); exists {
		if uid, ok := uidInterface.(uuid.UUID); ok {
			currentUserID = &uid
		}
	}

	// Récupérer les paramètres de recherche
	query := c.Query("q")
	userIDParam := c.Query("user_id")
	isPublicParam := c.Query("is_public")
	pageParam := c.DefaultQuery("page", "1")
	limitParam := c.DefaultQuery("limit", "20")

	// Parser les paramètres
	var filterUserID *uuid.UUID
	if userIDParam != "" {
		if parsed, err := uuid.Parse(userIDParam); err == nil {
			filterUserID = &parsed
		}
	}

	var filterIsPublic *bool
	if isPublicParam != "" {
		if parsed, err := strconv.ParseBool(isPublicParam); err == nil {
			filterIsPublic = &parsed
		}
	}

	page, err := strconv.Atoi(pageParam)
	if err != nil || page < 1 {
		page = 1
	}

	limit, err := strconv.Atoi(limitParam)
	if err != nil || limit < 1 {
		limit = 20
	}

	// Rechercher les playlists
	playlists, total, err := h.playlistService.SearchPlaylists(c.Request.Context(), services.SearchPlaylistsParams{
		Query:         query,
		UserID:        filterUserID,
		IsPublic:      filterIsPublic,
		Page:          page,
		Limit:         limit,
		CurrentUserID: currentUserID,
	})
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"playlists": playlists,
		"total":     total,
		"page":      page,
		"limit":     limit,
	})
}

// GetRecommendations gère la récupération des recommandations de playlists
// T0498: Create Playlist Recommendations
func (h *PlaylistHandler) GetRecommendations(c *gin.Context) {
	userID := c.MustGet("user_id").(uuid.UUID)
	if userID == uuid.Nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
		return
	}

	// Parser les paramètres de requête
	limitParam := c.DefaultQuery("limit", "20")
	limit, err := strconv.Atoi(limitParam)
	if err != nil || limit < 1 {
		limit = 20
	}
	if limit > 100 {
		limit = 100
	}

	minScoreParam := c.DefaultQuery("min_score", "0.1")
	minScore, err := strconv.ParseFloat(minScoreParam, 64)
	if err != nil || minScore < 0 {
		minScore = 0.1
	}

	includeOwnParam := c.DefaultQuery("include_own", "false")
	includeOwn := includeOwnParam == "true"

	// Créer le service de recommandations
	recommendationService := services.NewPlaylistRecommendationService(
		nil, // Le service utilisera les services injectés via les interfaces
		h.playlistService,
		h.playlistFollowService,
		nil, // logger
	)

	// Obtenir les recommandations
	recommendations, err := recommendationService.GetRecommendations(
		c.Request.Context(),
		services.GetRecommendationsParams{
			UserID:     userID,
			Limit:      limit,
			MinScore:   minScore,
			IncludeOwn: includeOwn,
		},
	)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	// Formater la réponse
	response := make([]gin.H, 0, len(recommendations))
	for _, rec := range recommendations {
		response = append(response, gin.H{
			"playlist": rec.Playlist,
			"score":    rec.Score,
			"reason":   rec.Reason,
		})
	}

	c.JSON(http.StatusOK, gin.H{
		"recommendations": response,
		"count":           len(response),
	})
}