package validator

import (
	"regexp"
	"strings"

	"github.com/topfans/backend/pkg/filter"
)

const (
	// MinPasswordLength 最小密码长度
	MinPasswordLength = 6
	// MaxPasswordLength 最大密码长度
	MaxPasswordLength = 50
	// MinNicknameLength 最小昵称长度
	MinNicknameLength = 2
	// MaxNicknameLength 最大昵称长度
	MaxNicknameLength = 20
)

var (
	// 中国手机号正则表达式
	mobileRegex = regexp.MustCompile(`^1[3-9]\d{9}$`)
	// 昵称正则：中文、英文、数字、下划线，首字符不能是数字或下划线
	nicknameRegex = regexp.MustCompile(`^[一-龥a-zA-Z][一-龥a-zA-Z0-9_]*$`)
)

// ValidateMobile 验证手机号格式
func ValidateMobile(mobile string) bool {
	if mobile == "" {
		return false
	}
	return mobileRegex.MatchString(mobile)
}

// ValidatePassword 验证密码强度
func ValidatePassword(password string) (bool, string) {
	if password == "" {
		return false, "password cannot be empty"
	}

	if len(password) < MinPasswordLength {
		return false, "password too short"
	}

	if len(password) > MaxPasswordLength {
		return false, "password too long"
	}

	return true, ""
}

// ValidateNickname 验证昵称
func ValidateNickname(nickname string) (bool, string) {
	if nickname == "" {
		return false, "nickname cannot be empty"
	}

	nickname = strings.TrimSpace(nickname)
	// 使用 rune 计数，支持中文等多字节字符
	runeCount := len([]rune(nickname))
	if runeCount < MinNicknameLength {
		return false, "nickname too short"
	}

	if runeCount > MaxNicknameLength {
		return false, "nickname too long"
	}

	// 格式校验：中文、英文、数字、下划线，首字符不能是数字或下划线
	if !nicknameRegex.MatchString(nickname) {
		return false, "invalid nickname format"
	}

	// 敏感词校验
	if filter.GetDefault().Contains(nickname) {
		return false, "nickname contains sensitive words"
	}

	return true, ""
}

// ValidateStarID 验证star_id
func ValidateStarID(starID int64) bool {
	return starID > 0
}

// ValidateUserID 验证user_id
func ValidateUserID(userID int64) bool {
	return userID > 0
}