<?php
declare (strict_types = 1);

namespace app\services\chat;

use app\model\api\ChatBalanceLog;
use app\model\api\ChatOrder;
use app\model\api\Sys;
use app\model\api\User;
use app\model\api\UserScoreDetail;

/**
 * 聊天次数余额服务
 */
class ChatBalanceService
{
    /**
     * 获取用户聊天次数
     * @param int $userId 用户ID
     * @return int
     */
    public static function getBalance(int $userId): int
    {
        $user = User::find($userId);
        return $user ? (int)($user->chat_num ?? 0) : 0;
    }
    
    /**
     * 增加聊天次数
     * @param int $userId 用户ID
     * @param int $num 增加数量
     * @param int $type 类型
     * @param string $remark 备注
     * @param int $relateId 关联ID
     * @return bool
     */
    public static function add(int $userId, int $num, int $type, string $remark = '', int $relateId = 0): bool
    {
        $user = User::find($userId);
        if (!$user) {
            return false;
        }
        
        $newBalance = (int)$user->chat_num + $num;
        
        $user->chat_num = $newBalance;
        $result = $user->save();
        
        if ($result) {
            ChatBalanceLog::record($userId, $type, $num, $newBalance, $remark, $relateId);
        }
        
        return $result;
    }
    
    /**
     * 减少聊天次数
     * @param int $userId 用户ID
     * @param int $num 减少数量
     * @param int $type 类型
     * @param string $remark 备注
     * @param int $relateId 关联ID
     * @return bool
     */
    public static function sub(int $userId, int $num, int $type, string $remark = '', int $relateId = 0): bool
    {
        $currentBalance = self::getBalance($userId);
        
        if ($currentBalance < $num) {
            return false;
        }
        
        $user = User::find($userId);
        if (!$user) {
            return false;
        }
        
        $newBalance = $currentBalance - $num;
        
        $user->chat_num = $newBalance;
        $result = $user->save();
        
        if ($result) {
            ChatBalanceLog::record($userId, $type, -$num, $newBalance, $remark, $relateId);
        }
        
        return $result;
    }
    
    /**
     * 扣除积分增加聊天次数（购买流程）
     * @param int $userId 用户ID
     * @param int $chatNum 购买次数
     * @param ChatOrder $order 订单
     * @return bool
     */
    public static function buyWithScore(int $userId, int $chatNum, ChatOrder $order): bool
    {
        $price = (int)$order->price;
        
        // 检查用户积分是否足够
        $userScore = (float)(new User)->where('uid', $userId)->value('score');
        if ($userScore < $price) {
            return false;
        }
        
        // 扣除积分
        $scoreResult = (new UserScoreDetail)->payScore($userId, $price, 'outcome_score', $order->order_no, [], '购买聊天次数', '购买聊天次数消费' . $price . '积分');
        if (!$scoreResult) {
            return false;
        }
        
        // 增加聊天次数
        return self::add($userId, $chatNum, ChatBalanceLog::TYPE_BUY, '积分购买聊天次数', (int)$order->id);
    }
    
    /**
     * 新用户赠送聊天次数
     * @param int $userId 用户ID
     * @param int $num 赠送次数
     * @return bool
     */
    public static function giftForNewUser(int $userId, int $num): bool
    {
        return self::add($userId, $num, ChatBalanceLog::TYPE_GIFT, '新用户赠送');
    }
    
    /**
     * 检查并扣除首次聊天次数
     * @param int $userId 用户ID（发起聊天方）
     * @param int $toUserId 对方用户ID
     * @return array ['success' => bool, 'message' => string]
     */
    public static function checkAndDeductFirstChat(int $userId, int $toUserId): array
    {
        // 检查是否已经扣过次数
        if (\app\model\api\ChatUserRelation::isDeducted($userId, $toUserId)) {
            return ['success' => true, 'message' => '已扣过次数'];
        }
        
        // 检查余额是否足够
        $balance = self::getBalance($userId);
        if ($balance <= 0) {
            return ['success' => false, 'message' => '聊天次数不足'];
        }
        
        // 扣除次数
        $result = self::sub($userId, 1, ChatBalanceLog::TYPE_FIRST_CHAT, '首次与用户' . $toUserId . '聊天', $toUserId);
        
        if ($result) {
            // 标记为已扣次数
            \app\model\api\ChatUserRelation::markDeducted($userId, $toUserId);
            return ['success' => true, 'message' => '扣除成功'];
        }
        
        return ['success' => false, 'message' => '扣除失败'];
    }
    
    /**
     * 获取购买价格
     * @return int 单次购买价格（积分）
     */
    public static function getBuyPrice(): int
    {
        $sys = Sys::find(1);
        return $sys ? (int)($sys->chat_price ?? 0) : 0;
    }
}