<?php

declare(strict_types=1);

namespace app\common\service\wechat;

use think\facade\Cache;
use think\facade\Log;

/**
 * 企业微信自建应用：向成员发送应用文本消息
 *
 * 依赖配置（与登录/绑定可共用 corp_id；发消息必须用「同一自建应用」的 AgentId + Secret）：
 * - WECHAT_WORK_CORP_ID 或 work_wechat.corp_id
 * - WECHAT_WORK_AGENT_ID 或 work_wechat.agent_id
 * - WECHAT_WORK_AGENT_SECRET 或 work_wechat.agent_secret（推荐；勿与仅用于网页授权的 secret 混用）
 * - 若未配 agent_secret，会回退 work_wechat.secret（若仍无法发消息，请在管理后台复制该应用的 Secret 填到 agent_secret）
 *
 * @see https://developer.work.weixin.qq.com/document/path/90236
 */
class WechatWorkAppMessageService
{
    /**
     * @return array{0: string, 1: int, 2: string} [corpId, agentId, secret]
     */
    private static function resolveMessagingCredentials(): array
    {
        $corpId = (string) env('WECHAT_WORK_CORP_ID', '');
        if ($corpId === '') {
            $corpId = (string) env('work_wechat.corp_id', '');
        }

        $agentIdStr = (string) env('WECHAT_WORK_AGENT_ID', '');
        if ($agentIdStr === '') {
            $agentIdStr = (string) env('work_wechat.agent_id', '');
        }
        $agentId = (int) $agentIdStr;

        $secret = (string) env('WECHAT_WORK_AGENT_SECRET', '');
        if ($secret === '') {
            $secret = (string) env('work_wechat.agent_secret', '');
        }
        if ($secret === '') {
            $secret = (string) env('work_wechat.secret', '');
        }

        return [$corpId, $agentId, $secret];
    }

    private static function getAccessToken(string $corpId, string $secret): ?string
    {
        if ($corpId === '' || $secret === '') {
            return null;
        }
        $cacheKey = 'work_wechat_app_msg_token_' . md5($corpId . $secret);
        $cached = Cache::get($cacheKey);
        if ($cached) {
            return (string) $cached;
        }

        $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid={$corpId}&corpsecret={$secret}";
        $res = self::httpGetJson($url);
        if (!$res || (int) ($res['errcode'] ?? -1) !== 0) {
            Log::error('企业微信应用 access_token 失败: ' . ($res['errmsg'] ?? '无响应'));

            return null;
        }
        $token = (string) ($res['access_token'] ?? '');
        if ($token === '') {
            return null;
        }
        $ttl = (int) ($res['expires_in'] ?? 7200) - 200;
        if ($ttl > 0) {
            Cache::set($cacheKey, $token, $ttl);
        }

        return $token;
    }

    /**
     * @return array<string,mixed>|null
     */
    private static function httpGetJson(string $url): ?array
    {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($ch, CURLOPT_TIMEOUT, 15);
        $result = curl_exec($ch);
        curl_close($ch);
        if ($result === false || $result === '') {
            return null;
        }
        $decoded = json_decode($result, true);

        return is_array($decoded) ? $decoded : null;
    }

    /**
     * @return array<string,mixed>|null
     */
    private static function httpPostJson(string $url, array $body): ?array
    {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($body, JSON_UNESCAPED_UNICODE));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json; charset=utf-8']);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($ch, CURLOPT_TIMEOUT, 15);
        $result = curl_exec($ch);
        curl_close($ch);
        if ($result === false || $result === '') {
            return null;
        }
        $decoded = json_decode($result, true);

        return is_array($decoded) ? $decoded : null;
    }

    /**
     * 向指定成员发送文本消息（userid 为企业微信成员账号，与后台 work_wechat_userid 一致）
     *
     * @return array{ok: bool, message?: string, errcode?: int}
     */
    public static function sendTextToUser(string $toUser, string $content): array
    {
        $toUser = trim($toUser);
        $content = trim($content);
        if ($toUser === '' || $content === '') {
            return ['ok' => false, 'message' => '接收人或消息内容为空'];
        }

        [$corpId, $agentId, $secret] = self::resolveMessagingCredentials();

        if ($corpId === '' || $agentId <= 0 || $secret === '') {
            Log::warning('企业微信应用消息未配置完整(corp_id/agent_id/secret)，跳过发消息');

            return [
                'ok' => false,
                'message' => '服务端未配置企业微信应用消息（需 corp_id、agent_id 及该应用的 Secret，建议配置 WECHAT_WORK_AGENT_SECRET）',
            ];
        }

        $token = self::getAccessToken($corpId, $secret);
        if (!$token) {
            return ['ok' => false, 'message' => '获取企业微信 access_token 失败，请查看服务端日志'];
        }

        $url = 'https://qyapi.weixin.qq.com/cgi-bin/message/send?access_token=' . urlencode($token);
        $body = [
            'touser' => $toUser,
            'msgtype' => 'text',
            'agentid' => $agentId,
            'text' => ['content' => $content],
            'safe' => 0,
        ];

        $res = self::httpPostJson($url, $body);
        if (!$res) {
            Log::error('企业微信发消息无响应');

            return ['ok' => false, 'message' => '企业微信接口无响应'];
        }
        $err = (int) ($res['errcode'] ?? -1);
        if ($err !== 0) {
            $errmsg = (string) ($res['errmsg'] ?? '');
            Log::error('企业微信发消息失败: ' . $errmsg . ' errcode=' . $err);

            $hint = '';
            if ($err === 81013 || $err === 60111) {
                $hint = '请核对开方人绑定的 userid 与企业微信成员账号一致，且成员已安装/可见该应用。';
            } elseif ($err === 60020) {
                $hint = '请将服务器出口 IP 加入企业微信应用可信 IP。';
            } elseif ($err === 60011) {
                $hint = '请检查应用是否具备发消息能力及可见范围是否包含该成员。';
            }

            return [
                'ok' => false,
                'message' => '企业微信返回：' . $errmsg . '（errcode=' . $err . '）' . ($hint !== '' ? ' ' . $hint : ''),
                'errcode' => $err,
            ];
        }

        return ['ok' => true];
    }
}