<?php

namespace app\util;

use GuzzleHttp\Client;
use GuzzleHttp\Exception\GuzzleException;
use GuzzleHttp\Psr7\Response;
use Psr\Http\Message\ResponseInterface;

class HttpClient
{
    /**
     * @var Client Guzzle客户端实例
     */
    private static $client;

    /**
     * 获取Guzzle客户端单例
     * @return Client
     */
    private static function getClient(): Client
    {
        if (!self::$client) {
            self::$client = new Client([
                'timeout' => 10, // 默认超时时间10秒
                'verify' => false, // 不验证SSL证书(生产环境建议设为true)
                'http_errors' => false, // 不抛出HTTP异常，自己处理
            ]);
        }
        return self::$client;
    }

    /**
     * 发送GET请求
     * @param string $url 请求地址
     * @param array $query 查询参数
     * @param array $headers 请求头
     * @return array
     */
    public static function get(string $url, array $query = [], array $headers = []): array
    {
        $options = [
            'query' => $query,
            'headers' => $headers
        ];
        return self::request('GET', $url, $options);
    }

    /**
     * 发送POST请求
     * @param string $url 请求地址
     * @param array|string $data 请求数据
     * @param array $headers 请求头
     * @param string $contentType 内容类型(form/json/xml)
     * @return array
     */
    public static function post(string $url, $data = [], array $headers = [], string $contentType = 'form'): array
    {
        $options = ['headers' => $headers];

        switch ($contentType) {
            case 'json':
                $options['json'] = $data;
                $options['headers']['Content-Type'] = 'application/json';
                break;
            /*case 'xml':
                $options['body'] = is_array($data) ? self::arrayToXml($data) : $data;
                $options['headers']['Content-Type'] = 'application/xml';
                break;*/
            default: // form
                $options['form_params'] = $data;
                $options['headers']['Content-Type'] = 'application/x-www-form-urlencoded';
        }

        return self::request('POST', $url, $options);
    }

    /**
     * 发送PUT请求
     * @param string $url 请求地址
     * @param array|string $data 请求数据
     * @param array $headers 请求头
     * @return array
     */
    public static function put(string $url, $data = [], array $headers = []): array
    {
        $options = [
            'json' => $data,
            'headers' => $headers
        ];
        return self::request('PUT', $url, $options);
    }

    /**
     * 发送DELETE请求
     * @param string $url 请求地址
     * @param array $data 请求数据
     * @param array $headers 请求头
     * @return array
     */
    public static function delete(string $url, array $data = [], array $headers = []): array
    {
        $options = [
            'json' => $data,
            'headers' => $headers
        ];
        return self::request('DELETE', $url, $options);
    }

    /**
     * 发送HTTP请求
     * @param string $method 请求方法
     * @param string $url 请求地址
     * @param array $options 请求选项
     * @return array
     */
    public static function request(string $method, string $url, array $options = []): array
    {
        try {
            $response = self::getClient()->request($method, $url, $options);
            return self::formatResponse($response);
        } catch (GuzzleException $e) {
            return [
                'status' => false,
                'code' => $e->getCode(),
                'message' => $e->getMessage(),
                'data' => null
            ];
        }
    }

    /**
     * 上传文件
     * @param string $url 请求地址
     * @param array $files 文件数组 [['name' => 'field_name', 'path' => 'file_path']]
     * @param array $form 其他表单数据
     * @param array $headers 请求头
     * @return array
     */
    public static function upload(string $url, array $files, array $form = [], array $headers = []): array
    {
        $multipart = [];

        // 添加文件
        foreach ($files as $file) {
            if (file_exists($file['path'])) {
                $multipart[] = [
                    'name' => $file['name'],
                    'contents' => fopen($file['path'], 'r'),
                    'filename' => basename($file['path'])
                ];
            }
        }

        // 添加其他表单数据
        foreach ($form as $name => $value) {
            $multipart[] = [
                'name' => $name,
                'contents' => $value
            ];
        }

        $options = [
            'multipart' => $multipart,
            'headers' => $headers
        ];

        return self::request('POST', $url, $options);
    }

    /**
     * 格式化响应
     * @param ResponseInterface $response
     * @return array
     */
    private static function formatResponse(ResponseInterface $response): array
    {
        $contents = $response->getBody()->getContents();
        $contentType = $response->getHeaderLine('Content-Type');

        $data = $contents;
        if (strpos($contentType, 'application/json') !== false) {
            $data = json_decode($contents, true) ?? $contents;
        }

        return [
            'status' => $response->getStatusCode() === 200,
            'code' => $response->getStatusCode(),
            'message' => $response->getReasonPhrase(),
            'data' => $data,
            'headers' => $response->getHeaders()
        ];
    }

    /**
     * 数组转XML
     * @param array $data
     * @param string $rootNode
     * @return string
     */
    private static function arrayToXml(array $data, string $rootNode = 'root'): string
    {
        $xml = new \SimpleXMLElement('<' . $rootNode . '/>');
        self::addDataToXml($xml, $data);
        return $xml->asXML();
    }

    /**
     * 递归添加数据到XML
     * @param \SimpleXMLElement $xml
     * @param array $data
     */
    private static function addDataToXml(\SimpleXMLElement $xml, array $data)
    {
        foreach ($data as $key => $value) {
            if (is_array($value)) {
                if (is_numeric($key)) {
                    $key = 'item';
                }
                $subNode = $xml->addChild($key);
                self::addDataToXml($subNode, $value);
            } else {
                $xml->addChild($key, htmlspecialchars($value));
            }
        }
    }
}