<?php
class CurlRequest
{
	public static function post($url, $data, $headers=[], $user=false)
	{
		foreach ($data as &$d) {
			$d = urlencode($d);
		}
		$fields_string = "";
		foreach($data as $key=>$value) { $fields_string .= $key.'='.$value.'&'; }
		$ch = curl_init($url);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);
		curl_setopt($ch,CURLOPT_POST, count($data));
		if ($user) {
			curl_setopt($ch, CURLOPT_USERPWD, $user);
		}
		curl_setopt($ch,CURLOPT_POSTFIELDS, $fields_string);
		$q = curl_exec($ch);
		$q2 = curl_getinfo($ch,CURLINFO_HTTP_CODE);
		curl_close($ch);
		if ($q2 == 200) {
			return $q;
		} else {
			return false;
		}
	}
	public static function get($url, $data, $headers=[])
	{
		foreach ($data as &$d) {
			$d = urlencode($d);
		}
		$fields_string = "";
		foreach($data as $key=>$value) { $fields_string .= $key.'='.$value.'&'; }
		$ch = curl_init($url."?".$fields_string);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);
		$q = curl_exec($ch);
		curl_close($ch);
		return $q;
	}
}
class PayPal
{
	private $clientId;
	private $clientSecret;
	private $accessToken;
	public function __construct($clientId, $clientSecret)
	{
		$this->clientId = $clientId;
		$this->clientSecret = $clientSecret;
		$q = CurlRequest::post("https://api.sandbox.paypal.com/v1/oauth2/token",["grant_type" => "client_credentials"],["Accept: application/json"],$clientId.":".$clientSecret);
		if($q) {
			$q = json_decode($q,true);
			$this->accessToken = $q['access_token'];
			echo $this->accessToken;
		}
	}
	public function pay()
	{
		$q =  CurlRequest::post("",["access_token" => $this->accessToken, "amount" => ]);
	}
}

$p = new PayPal("AQr-2Wl1kauMouHhW95aJzQLWjHUuypVq4O1WV3tXrZ9zixW9-Qcdtil-fNYsrDjtQ8JoCAFBiCCh3ah","EJ49tuWUksfOhUc-2hFghE-P1ncwTL_dKsZbHN3A--A7ohIeqj7E9B1Gtq6t_K9tVmfKBvp_qI7sjYEX");