<?php
/**
 * Created by PhpStorm.
 * User: FZS
 * Time: 2019/3/13 17:10
 */
//----------------------------------
// 百度增值税发票识别调用类
//----------------------------------
class freeApi{
    private $apiKey = false; //百度应用AppID
    private $secretKey = false; //百度应用API Key
    private $tokenUrl = 'https://aip.baidubce.com/oauth/2.0/token';
    private $apiUrl = 'https://aip.baidubce.com/rest/2.0/ocr/v1/vat_invoice';
    public function __construct($apikey,$secretkey){
        $this->apiKey = $apikey;
        $this->secretKey = $secretkey;
    }
    /**
     * 获取token
     * @return array
     */
    public function getToken(){
        $params = [
            'grant_type' => 'client_credentials',
            'client_id'  => $this->apiKey,
            'client_secret' => $this->secretKey,
        ];
        $params = $this->handleUrl($params);
        return $this->returnArray($this->freeApiCurl($this->tokenUrl,$params,1));
    }
    /**
     * url拼接
     * @return string
     */
    private function handleUrl($params){
        $o = "";
        foreach ( $params as $k => $v )
        {
            $o.= "$k=" . urlencode( $v ). "&" ;
        }
        $params = substr($o,0,-1);
        return $params;
    }
    /**
     * 将JSON内容转为数据，并返回
     * @param string $content [内容]
     * @return array
     */
    public function returnArray($content){
        return json_decode($content,true);
    }
    /**
     * 获取增值税发票证识别结果
     * @return array
     */
    public function getResult(){
        $params = [
            'image' => base64_encode(file_get_contents('图片路径')),
        ];
        return $this->returnArray($this->freeApiCurl($this->apiUrl.'?access_token='.$this->getToken()['access_token'],$params,1));
    }
    /**
     * 请求接口返回内容
     * @param  string $url [请求的URL地址]
     * @param  string $params [请求的参数]
     * @param  int $ipost [是否采用POST形式]
     * @return  string
     */
    public function freeApiCurl($url,$params=false,$ispost=0){
        $httpInfo = array();
        $ch = curl_init();
        curl_setopt( $ch, CURLOPT_HTTP_VERSION , CURL_HTTP_VERSION_1_1 );
        curl_setopt( $ch, CURLOPT_HTTP_VERSION , CURL_HTTP_VERSION_1_1 );
        curl_setopt( $ch, CURLOPT_USERAGENT , 'free-api' );
        curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT , 60 );
        curl_setopt( $ch, CURLOPT_TIMEOUT , 60);
        curl_setopt( $ch, CURLOPT_RETURNTRANSFER , true );
        if( $ispost )
        {
            curl_setopt( $ch , CURLOPT_POST , true );
            curl_setopt( $ch , CURLOPT_POSTFIELDS , $params );
            curl_setopt( $ch , CURLOPT_URL , $url );
        }
        else
        {
            if($params){
                curl_setopt( $ch , CURLOPT_URL , $url.'?'.$params );
            }else{
                curl_setopt( $ch , CURLOPT_URL , $url);
            }
        }
        $response = curl_exec( $ch );
        if ($response === FALSE) {
            return false;
        }
        $httpCode = curl_getinfo( $ch , CURLINFO_HTTP_CODE );
        $httpInfo = array_merge( $httpInfo , curl_getinfo( $ch ) );
        curl_close( $ch );
        return $response;
    }
}