<?php
namespace addons\shopro\library;

use app\admin\model\shopro\user\User as UserModel;

/**
 * 邀请码工具类
 */
class InviteHelper
{
    /**
     * 为用户生成邀请码
     * @param int $userId 用户ID
     * @return string 邀请码
     */
    public static function generateCode($userId)
    {
        $user = UserModel::find($userId);

        if (!$user) {
            return '';
        }

        // 已有邀请码直接返回
        if ($user->invite_code) {
            return $user->invite_code;
        }

        // 生成唯一邀请码（排除易混淆字符）
        $chars = 'ABCDEFGHJKMNPQRSTUVWXYZ23456789';
        $maxAttempts = 50;

        for ($i = 0; $i < $maxAttempts; $i++) {
            $code = '';
            for ($j = 0; $j < 6; $j++) {
                $code .= $chars[mt_rand(0, strlen($chars) - 1)];
            }

            // 检查是否重复
            if (!UserModel::where('invite_code', $code)->find()) {
                $user->invite_code = $code;
                $user->save();
                return $code;
            }
        }

        // 兜底：用MD5
        $code = strtoupper(substr(md5($userId . time() . mt_rand()), 0, 6));
        $user->invite_code = $code;
        $user->save();

        return $code;
    }

    /**
     * 验证邀请码
     * @param string $inviteCode 邀请码
     * @return array
     */
    public static function validate($inviteCode)
    {
        $inviteCode = strtoupper(trim($inviteCode));

        if (strlen($inviteCode) !== 6) {
            return ['code' => 0, 'msg' => '邀请码格式错误'];
        }

        $inviter = UserModel::where('invite_code', $inviteCode)
            ->where('status', 'normal')
            ->field(['id', 'nickname', 'avatar', 'invite_code'])
            ->find();

        if (!$inviter) {
            return ['code' => 0, 'msg' => '邀请码不存在'];
        }

        return [
            'code' => 1,
            'msg' => '邀请码有效',
            'data' => [
                'user_id' => $inviter->id,
                'invite_code' => $inviter->invite_code,
                'inviter' => [
                    'id' => $inviter->id,
                    'nickname' => $inviter->nickname,
                    'avatar' => $inviter->avatar
                ]
            ]
        ];
    }

    /**
     * 绑定上下级关系
     * @param string $inviteCode 邀请码
     * @param int $userId 被邀请人ID
     * @return array
     */
    public static function bind($inviteCode, $userId)
    {
        $inviteCode = strtoupper(trim($inviteCode));
        $user = UserModel::find($userId);

        if (!$user) {
            return ['code' => 0, 'msg' => '用户不存在'];
        }

        // 已绑定过上级
        if ($user->parent_user_id !== null) {
            return ['code' => 0, 'msg' => '您已有推荐人，无法修改'];
        }

        // 验证邀请码
        $validateResult = self::validate($inviteCode);
        if ($validateResult['code'] != 1) {
            return $validateResult;
        }

        $inviterUserId = $validateResult['data']['user_id'];

        // 不能邀请自己
        if ($inviterUserId == $userId) {
            return ['code' => 0, 'msg' => '不能使用自己的邀请码'];
        }

        // 绑定
        $user->parent_user_id = $inviterUserId;
        $user->invite_code_used = $inviteCode;
        $user->save();

        \think\Log::info("邀请码绑定: 邀请人[{$inviterUserId}] -> 被邀请人[{$userId}] 邀请码[{$inviteCode}]");

        // 触发分销业绩统计
        $agent = new \addons\shopro\service\commission\Agent($userId);
        $agent->createAsyncAgentUpgrade($userId);

        // 添加分销推广记录
        \app\admin\model\shopro\commission\Log::add(
            $inviterUserId,
            'share',
            ['user' => $user, 'type' => 'invite_code']
        );

        return [
            'code' => 1,
            'msg' => '绑定成功',
            'data' => $validateResult['data']
        ];
    }
}