package repository

import (
	"context"
	"errors"
	"time"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"

	"tm/internal/domain"
	"tm/pkg/logger"
)

// UserRepositoryImpl implements the UserRepository interface
type UserRepositoryImpl struct {
	collection *mongo.Collection
	logger     logger.Logger
}

// NewUserRepository creates a new panel user repository
func NewUserRepository(db *mongo.Database, logger logger.Logger) domain.UserRepository {
	collection := db.Collection("users")

	// Create indexes
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// Email index (unique)
	emailIndex := mongo.IndexModel{
		Keys:    bson.D{{"email", 1}},
		Options: options.Index().SetUnique(true),
	}

	// Role index
	roleIndex := mongo.IndexModel{
		Keys: bson.D{{"role", 1}},
	}

	// Active status index
	activeIndex := mongo.IndexModel{
		Keys: bson.D{{"is_active", 1}},
	}

	// Department index
	departmentIndex := mongo.IndexModel{
		Keys: bson.D{{"department", 1}},
	}

	// Created at index
	createdAtIndex := mongo.IndexModel{
		Keys: bson.D{{"created_at", -1}},
	}

	_, err := collection.Indexes().CreateMany(ctx, []mongo.IndexModel{
		emailIndex,
		roleIndex,
		activeIndex,
		departmentIndex,
		createdAtIndex,
	})

	if err != nil {
		logger.Warn("Failed to create user indexes", map[string]interface{}{
			"error": err.Error(),
		})
	}

	return &UserRepositoryImpl{
		collection: collection,
		logger:     logger,
	}
}

// Create creates a new panel user
func (r *UserRepositoryImpl) Create(ctx context.Context, user *domain.User) error {
	// Set created/updated timestamps
	now := time.Now()
	user.CreatedAt = now
	user.UpdatedAt = now

	// Insert user
	_, err := r.collection.InsertOne(ctx, user)
	if err != nil {
		if mongo.IsDuplicateKeyError(err) {
			return errors.New("user already exists")
		}
		r.logger.Error("Failed to create user", map[string]interface{}{
			"error":   err.Error(),
			"email":   user.Email,
			"user_id": user.ID.String(),
		})
		return err
	}

	r.logger.Info("Panel user created successfully", map[string]interface{}{
		"user_id": user.ID.String(),
		"email":   user.Email,
		"role":    user.Role,
	})

	return nil
}

// GetByID retrieves a panel user by ID
func (r *UserRepositoryImpl) GetByID(ctx context.Context, id uuid.UUID) (*domain.User, error) {
	var user domain.User

	filter := bson.M{"_id": id}
	err := r.collection.FindOne(ctx, filter).Decode(&user)

	if err != nil {
		if err == mongo.ErrNoDocuments {
			return nil, errors.New("user not found")
		}
		r.logger.Error("Failed to get user by ID", map[string]interface{}{
			"error":   err.Error(),
			"user_id": id.String(),
		})
		return nil, err
	}

	return &user, nil
}

// GetByEmail retrieves a panel user by email
func (r *UserRepositoryImpl) GetByEmail(ctx context.Context, email string) (*domain.User, error) {
	var user domain.User

	filter := bson.M{"email": email}
	err := r.collection.FindOne(ctx, filter).Decode(&user)

	if err != nil {
		if err == mongo.ErrNoDocuments {
			return nil, errors.New("user not found")
		}
		r.logger.Error("Failed to get user by email", map[string]interface{}{
			"error": err.Error(),
			"email": email,
		})
		return nil, err
	}

	return &user, nil
}

// Update updates a panel user
func (r *UserRepositoryImpl) Update(ctx context.Context, user *domain.User) error {
	// Set updated timestamp
	user.UpdatedAt = time.Now()

	filter := bson.M{"_id": user.ID}
	update := bson.M{"$set": user}

	result, err := r.collection.UpdateOne(ctx, filter, update)
	if err != nil {
		r.logger.Error("Failed to update user", map[string]interface{}{
			"error":   err.Error(),
			"user_id": user.ID.String(),
		})
		return err
	}

	if result.MatchedCount == 0 {
		return errors.New("user not found")
	}

	r.logger.Info("Panel user updated successfully", map[string]interface{}{
		"user_id": user.ID.String(),
		"email":   user.Email,
	})

	return nil
}

// Delete deletes a panel user (soft delete by setting is_active to false)
func (r *UserRepositoryImpl) Delete(ctx context.Context, id uuid.UUID) error {
	filter := bson.M{"_id": id}
	update := bson.M{
		"$set": bson.M{
			"is_active":  false,
			"updated_at": time.Now(),
		},
	}

	result, err := r.collection.UpdateOne(ctx, filter, update)
	if err != nil {
		r.logger.Error("Failed to delete user", map[string]interface{}{
			"error":   err.Error(),
			"user_id": id.String(),
		})
		return err
	}

	if result.MatchedCount == 0 {
		return errors.New("user not found")
	}

	r.logger.Info("Panel user deleted successfully", map[string]interface{}{
		"user_id": id.String(),
	})

	return nil
}

// List retrieves panel users with pagination
func (r *UserRepositoryImpl) List(ctx context.Context, limit, offset int) ([]*domain.User, error) {
	var users []*domain.User

	// Build options
	opts := options.Find()
	opts.SetLimit(int64(limit))
	opts.SetSkip(int64(offset))
	opts.SetSort(bson.D{{"created_at", -1}}) // Sort by created_at desc

	// Only active users by default
	filter := bson.M{"is_active": true}

	cursor, err := r.collection.Find(ctx, filter, opts)
	if err != nil {
		r.logger.Error("Failed to list users", map[string]interface{}{
			"error":  err.Error(),
			"limit":  limit,
			"offset": offset,
		})
		return nil, err
	}
	defer cursor.Close(ctx)

	if err = cursor.All(ctx, &users); err != nil {
		r.logger.Error("Failed to decode users", map[string]interface{}{
			"error": err.Error(),
		})
		return nil, err
	}

	return users, nil
}

// GetByRole retrieves panel users by role with pagination
func (r *UserRepositoryImpl) GetByRole(ctx context.Context, role domain.UserRole, limit, offset int) ([]*domain.User, error) {
	var users []*domain.User

	// Build options
	opts := options.Find()
	opts.SetLimit(int64(limit))
	opts.SetSkip(int64(offset))
	opts.SetSort(bson.D{{"created_at", -1}}) // Sort by created_at desc

	// Filter by role and active status
	filter := bson.M{
		"role":      role,
		"is_active": true,
	}

	cursor, err := r.collection.Find(ctx, filter, opts)
	if err != nil {
		r.logger.Error("Failed to get users by role", map[string]interface{}{
			"error":  err.Error(),
			"role":   role,
			"limit":  limit,
			"offset": offset,
		})
		return nil, err
	}
	defer cursor.Close(ctx)

	if err = cursor.All(ctx, &users); err != nil {
		r.logger.Error("Failed to decode users by role", map[string]interface{}{
			"error": err.Error(),
			"role":  role,
		})
		return nil, err
	}

	return users, nil
}

// UpdatePermissions updates panel user permissions
func (r *UserRepositoryImpl) UpdatePermissions(ctx context.Context, id uuid.UUID, permissions []string) error {
	filter := bson.M{"_id": id}
	update := bson.M{
		"$set": bson.M{
			"permissions": permissions,
			"updated_at":  time.Now(),
		},
	}

	result, err := r.collection.UpdateOne(ctx, filter, update)
	if err != nil {
		r.logger.Error("Failed to update user permissions", map[string]interface{}{
			"error":       err.Error(),
			"user_id":     id.String(),
			"permissions": permissions,
		})
		return err
	}

	if result.MatchedCount == 0 {
		return errors.New("user not found")
	}

	r.logger.Info("Panel user permissions updated successfully", map[string]interface{}{
		"user_id":     id.String(),
		"permissions": permissions,
	})

	return nil
}