package service

import (
	"errors"
	"fmt"
	"io"
	"mime/multipart"
	"os"
	"path/filepath"
	"strings"
	"time"

	"git.iioio.com/freefire/jiang13-forum/model"
)

type UserService struct {
	filter *SensitiveFilter
}

func NewUserService(filter *SensitiveFilter) *UserService {
	return &UserService{filter: filter}
}

// GetByID 获取用户信息
func (s *UserService) GetByID(id uint) (*model.User, error) {
	var user model.User
	if err := model.DB.First(&user, id).Error; err != nil {
		return nil, err
	}
	return &user, nil
}

// GetByUsername 按用户名查询
func (s *UserService) GetByUsername(username string) (*model.User, error) {
	var user model.User
	if err := model.DB.Where("username = ?", username).First(&user).Error; err != nil {
		return nil, err
	}
	return &user, nil
}

// UpdateNickname 修改昵称
func (s *UserService) UpdateNickname(userID uint, nickname string) error {
	nickname = strings.TrimSpace(nickname)
	if nickname == "" {
		return errors.New("昵称不能为空")
	}
	nickname = s.filter.Filter(nickname)
	return model.DB.Model(&model.User{}).Where("id = ?", userID).Update("nickname", nickname).Error
}

// UpdatePassword 修改密码
func (s *UserService) UpdatePassword(userID uint, oldPass, newPass string) error {
	if err := ValidatePassword(newPass); err != nil {
		return err
	}
	var user model.User
	if err := model.DB.First(&user, userID).Error; err != nil {
		return err
	}
	if !CheckPassword(user.Password, oldPass) {
		return errors.New("原密码错误")
	}
	hash, err := HashPassword(newPass)
	if err != nil {
		return err
	}
	return model.DB.Model(&user).Update("password", hash).Error
}

// UploadAvatar 上传头像到本地目录
func (s *UserService) UploadAvatar(userID uint, file *multipart.FileHeader, uploadDir string) (string, error) {
	ext := strings.ToLower(filepath.Ext(file.Filename))
	allowed := map[string]bool{".jpg": true, ".jpeg": true, ".png": true, ".gif": true, ".webp": true}
	if !allowed[ext] {
		return "", errors.New("仅支持 jpg/png/gif/webp 格式")
	}
	filename := fmt.Sprintf("%d%s", userID, ext)
	destPath := filepath.Join(uploadDir, filename)

	src, err := file.Open()
	if err != nil {
		return "", err
	}
	defer src.Close()

	dst, err := os.Create(destPath)
	if err != nil {
		return "", err
	}
	defer dst.Close()

	if _, err := io.Copy(dst, src); err != nil {
		return "", err
	}

	avatarURL := "/uploads/avatars/" + filename
	return avatarURL, model.DB.Model(&model.User{}).Where("id = ?", userID).Update("avatar", avatarURL).Error
}

// ListUsers 管理员列出用户
func (s *UserService) ListUsers(page, size int) ([]model.User, int64, error) {
	var users []model.User
	var total int64
	model.DB.Model(&model.User{}).Count(&total)
	offset := (page - 1) * size
	err := model.DB.Order("id desc").Offset(offset).Limit(size).Find(&users).Error
	return users, total, err
}

// BanUser 禁言用户
func (s *UserService) BanUser(userID uint, banned bool) error {
	var user model.User
	if err := model.DB.First(&user, userID).Error; err != nil {
		return errors.New("用户不存在")
	}
	if user.Role == model.RoleAdmin {
		return errors.New("不能禁言管理员账号")
	}
	now := time.Now()
	updates := map[string]interface{}{"banned": banned}
	if banned {
		updates["banned_at"] = &now
	}
	return model.DB.Model(&model.User{}).Where("id = ?", userID).Updates(updates).Error
}