package customer

import (
	"context"
	"errors"
	"time"
	"tm/pkg/logger"
	mongopkg "tm/pkg/mongo"

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

// Repository defines methods for customer (mobile user) data access
type Repository interface {
	Create(ctx context.Context, customer *Customer) error
	GetByID(ctx context.Context, id uuid.UUID) (*Customer, error)
	GetByEmail(ctx context.Context, email string) (*Customer, error)
	GetByUsername(ctx context.Context, username string) (*Customer, error)
	GetByMobile(ctx context.Context, mobile string) (*Customer, error)
	Update(ctx context.Context, customer *Customer) error
	Delete(ctx context.Context, id uuid.UUID) error
	List(ctx context.Context, limit, offset int) ([]*Customer, error)
	Search(ctx context.Context, search string, status *string, gender *string, companyID *uuid.UUID, limit, offset int, sortBy, sortOrder string) ([]*Customer, error)
	GetByCompanyID(ctx context.Context, companyID uuid.UUID, limit, offset int) ([]*Customer, error)
	AddDeviceToken(ctx context.Context, id uuid.UUID, deviceToken DeviceToken) error
	RemoveDeviceToken(ctx context.Context, id uuid.UUID, token string) error
	UpdateLastLogin(ctx context.Context, id uuid.UUID) error
	GetAllDeviceTokens(ctx context.Context) ([]DeviceToken, error)
}

// customerRepository implements the Repository interface
type customerRepository struct {
	collection *mongo.Collection
	logger     logger.Logger
}

// NewCustomerRepository creates a new customer repository
func NewCustomerRepository(mongoManager *mongopkg.ConnectionManager, logger logger.Logger) Repository {
	collection := mongoManager.GetCollection("customers")

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

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

	// Username index (unique)
	usernameIndex := mongo.IndexModel{
		Keys:    bson.D{{Key: "username", Value: 1}},
		Options: options.Index().SetUnique(true),
	}

	// Mobile index (unique)
	mobileIndex := mongo.IndexModel{
		Keys:    bson.D{{Key: "mobile", Value: 1}},
		Options: options.Index().SetUnique(true),
	}

	// Company ID index
	companyIndex := mongo.IndexModel{
		Keys: bson.D{{Key: "company_id", Value: 1}},
	}

	// Status index
	statusIndex := mongo.IndexModel{
		Keys: bson.D{{Key: "status", Value: 1}},
	}

	// Gender index
	genderIndex := mongo.IndexModel{
		Keys: bson.D{{Key: "gender", Value: 1}},
	}

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

	// Full text search index
	textIndex := mongo.IndexModel{
		Keys: bson.D{
			{Key: "full_name", Value: "text"},
			{Key: "email", Value: "text"},
			{Key: "mobile", Value: "text"},
			{Key: "username", Value: "text"},
		},
	}

	_, err := collection.Indexes().CreateMany(ctx, []mongo.IndexModel{
		emailIndex,
		usernameIndex,
		mobileIndex,
		companyIndex,
		statusIndex,
		genderIndex,
		createdAtIndex,
		textIndex,
	})

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

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

// Create creates a new customer
func (r *customerRepository) Create(ctx context.Context, customer *Customer) error {
	// Set created/updated timestamps using Unix timestamps
	now := time.Now().Unix()
	customer.CreatedAt = now
	customer.UpdatedAt = now

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

	r.logger.Info("Customer created successfully", map[string]interface{}{
		"customer_id": customer.ID.String(),
		"email":       customer.Email,
	})

	return nil
}

// GetByID retrieves a customer by ID
func (r *customerRepository) GetByID(ctx context.Context, id uuid.UUID) (*Customer, error) {
	var customer Customer

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

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

	return &customer, nil
}

// GetByEmail retrieves a customer by email
func (r *customerRepository) GetByEmail(ctx context.Context, email string) (*Customer, error) {
	var customer Customer

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

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

	return &customer, nil
}

// GetByUsername retrieves a customer by username
func (r *customerRepository) GetByUsername(ctx context.Context, username string) (*Customer, error) {
	var customer Customer

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

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

	return &customer, nil
}

// GetByMobile retrieves a customer by mobile
func (r *customerRepository) GetByMobile(ctx context.Context, mobile string) (*Customer, error) {
	var customer Customer

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

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

	return &customer, nil
}

// Update updates a customer
func (r *customerRepository) Update(ctx context.Context, customer *Customer) error {
	// Set updated timestamp using Unix timestamp
	customer.UpdatedAt = time.Now().Unix()

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

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

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

	r.logger.Info("Customer updated successfully", map[string]interface{}{
		"customer_id": customer.ID.String(),
		"email":       customer.Email,
	})

	return nil
}

// Delete deletes a customer (soft delete by setting is_active to false)
func (r *customerRepository) 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().Unix(),
		},
	}

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

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

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

	return nil
}

// List retrieves customers with pagination
func (r *customerRepository) List(ctx context.Context, limit, offset int) ([]*Customer, error) {
	var customers []*Customer

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

	// Only active customers by default
	filter := bson.M{"status": "active"}

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

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

	return customers, nil
}

// Search retrieves customers with search and filters
func (r *customerRepository) Search(ctx context.Context, search string, status *string, gender *string, companyID *uuid.UUID, limit, offset int, sortBy, sortOrder string) ([]*Customer, error) {
	var customers []*Customer

	// Build filter
	filter := bson.M{}

	if search != "" {
		filter["$text"] = bson.M{"$search": search}
	}

	if status != nil {
		filter["status"] = *status
	}

	if gender != nil {
		filter["gender"] = *gender
	}

	if companyID != nil {
		filter["company_id"] = *companyID
	}

	// Build options
	opts := options.Find()
	opts.SetLimit(int64(limit))
	opts.SetSkip(int64(offset))

	// Set sort
	if sortBy != "" {
		sortValue := 1
		if sortOrder == "desc" {
			sortValue = -1
		}
		opts.SetSort(bson.D{{Key: sortBy, Value: sortValue}})
	} else {
		opts.SetSort(bson.D{{Key: "created_at", Value: -1}}) // Default sort
	}

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

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

	return customers, nil
}

// GetByCompanyID retrieves customers by company ID with pagination
func (r *customerRepository) GetByCompanyID(ctx context.Context, companyID uuid.UUID, limit, offset int) ([]*Customer, error) {
	var customers []*Customer

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

	// Filter by company ID and active status
	filter := bson.M{
		"company_id": companyID,
		"status":     "active",
	}

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

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

	return customers, nil
}

// AddDeviceToken adds a device token for push notifications
func (r *customerRepository) AddDeviceToken(ctx context.Context, id uuid.UUID, deviceToken DeviceToken) error {
	// Set timestamps
	now := time.Now().Unix()
	deviceToken.CreatedAt = now
	deviceToken.UpdatedAt = now

	filter := bson.M{"_id": id}
	update := bson.M{
		"$push": bson.M{"device_tokens": deviceToken}, // Use $push to add new token
		"$set":  bson.M{"updated_at": now},
	}

	result, err := r.collection.UpdateOne(ctx, filter, update)
	if err != nil {
		r.logger.Error("Failed to add device token", map[string]interface{}{
			"error":       err.Error(),
			"customer_id": id.String(),
			"token":       deviceToken.Token,
		})
		return err
	}

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

	r.logger.Info("Device token added successfully", map[string]interface{}{
		"customer_id": id.String(),
		"token":       deviceToken.Token,
		"device_type": deviceToken.DeviceType,
	})

	return nil
}

// RemoveDeviceToken removes a device token
func (r *customerRepository) RemoveDeviceToken(ctx context.Context, id uuid.UUID, token string) error {
	filter := bson.M{"_id": id}
	update := bson.M{
		"$pull": bson.M{"device_tokens": bson.M{"token": token}}, // Use $pull to remove the token
		"$set":  bson.M{"updated_at": time.Now().Unix()},
	}

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

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

	r.logger.Info("Device token removed successfully", map[string]interface{}{
		"customer_id": id.String(),
		"token":       token,
	})

	return nil
}

// UpdateLastLogin updates the last login timestamp
func (r *customerRepository) UpdateLastLogin(ctx context.Context, id uuid.UUID) error {
	filter := bson.M{"_id": id}
	update := bson.M{
		"$set": bson.M{
			"last_login_at": time.Now().Unix(),
			"updated_at":    time.Now().Unix(),
		},
	}

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

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

	r.logger.Info("Last login updated successfully", map[string]interface{}{
		"customer_id": id.String(),
	})

	return nil
}

// GetAllDeviceTokens retrieves all device tokens for push notifications
func (r *customerRepository) GetAllDeviceTokens(ctx context.Context) ([]DeviceToken, error) {
	var customers []*Customer

	// Get all active customers
	filter := bson.M{"status": "active"}
	opts := options.Find().SetProjection(bson.M{"device_tokens": 1})

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

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

	// Collect all device tokens
	var allTokens []DeviceToken
	for _, customer := range customers {
		allTokens = append(allTokens, customer.DeviceTokens...)
	}

	r.logger.Info("Retrieved all device tokens", map[string]interface{}{
		"total_tokens": len(allTokens),
	})

	return allTokens, nil
}