package postgres

import (
	"fmt"
	"photography-backend/internal/models"
	"gorm.io/gorm"
)

// UserRepository 用户仓库接口
type UserRepository interface {
	Create(user *models.User) error
	GetByID(id uint) (*models.User, error)
	GetByUsername(username string) (*models.User, error)
	GetByEmail(email string) (*models.User, error)
	Update(user *models.User) error
	Delete(id uint) error
	List(page, limit int, role string, isActive *bool) ([]*models.User, int64, error)
	UpdateLastLogin(id uint) error
}

// userRepository 用户仓库实现
type userRepository struct {
	db *gorm.DB
}

// NewUserRepository 创建用户仓库
func NewUserRepository(db *gorm.DB) UserRepository {
	return &userRepository{db: db}
}

// Create 创建用户
func (r *userRepository) Create(user *models.User) error {
	if err := r.db.Create(user).Error; err != nil {
		return fmt.Errorf("failed to create user: %w", err)
	}
	return nil
}

// GetByID 根据ID获取用户
func (r *userRepository) GetByID(id uint) (*models.User, error) {
	var user models.User
	if err := r.db.First(&user, id).Error; err != nil {
		if err == gorm.ErrRecordNotFound {
			return nil, nil
		}
		return nil, fmt.Errorf("failed to get user by id: %w", err)
	}
	return &user, nil
}

// GetByUsername 根据用户名获取用户
func (r *userRepository) GetByUsername(username string) (*models.User, error) {
	var user models.User
	if err := r.db.Where("username = ?", username).First(&user).Error; err != nil {
		if err == gorm.ErrRecordNotFound {
			return nil, nil
		}
		return nil, fmt.Errorf("failed to get user by username: %w", err)
	}
	return &user, nil
}

// GetByEmail 根据邮箱获取用户
func (r *userRepository) GetByEmail(email string) (*models.User, error) {
	var user models.User
	if err := r.db.Where("email = ?", email).First(&user).Error; err != nil {
		if err == gorm.ErrRecordNotFound {
			return nil, nil
		}
		return nil, fmt.Errorf("failed to get user by email: %w", err)
	}
	return &user, nil
}

// Update 更新用户
func (r *userRepository) Update(user *models.User) error {
	if err := r.db.Save(user).Error; err != nil {
		return fmt.Errorf("failed to update user: %w", err)
	}
	return nil
}

// Delete 删除用户
func (r *userRepository) Delete(id uint) error {
	if err := r.db.Delete(&models.User{}, id).Error; err != nil {
		return fmt.Errorf("failed to delete user: %w", err)
	}
	return nil
}

// List 获取用户列表
func (r *userRepository) List(page, limit int, role string, isActive *bool) ([]*models.User, int64, error) {
	var users []*models.User
	var total int64
	
	query := r.db.Model(&models.User{})
	
	// 添加过滤条件
	if role != "" {
		query = query.Where("role = ?", role)
	}
	if isActive != nil {
		query = query.Where("is_active = ?", *isActive)
	}
	
	// 计算总数
	if err := query.Count(&total).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to count users: %w", err)
	}
	
	// 分页查询
	offset := (page - 1) * limit
	if err := query.Offset(offset).Limit(limit).
		Order("created_at DESC").
		Find(&users).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to list users: %w", err)
	}
	
	return users, total, nil
}

// UpdateLastLogin 更新最后登录时间
func (r *userRepository) UpdateLastLogin(id uint) error {
	if err := r.db.Model(&models.User{}).Where("id = ?", id).
		Update("last_login", gorm.Expr("NOW()")).Error; err != nil {
		return fmt.Errorf("failed to update last login: %w", err)
	}
	return nil
}