<?php
/**
 * Copyright 2014 Freemius, Inc.
 *
 * Licensed under the GPL v2 (the "License"); you may
 * not use this file except in compliance with the License. You may obtain
 * a copy of the License at
 *
 *     http://choosealicense.com/licenses/gpl-v2/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

if ( ! defined( 'FS_API__VERSION' ) ) {
	define( 'FS_API__VERSION', '1' );
}
if ( ! defined( 'FS_SDK__PATH' ) ) {
	define( 'FS_SDK__PATH', dirname( __FILE__ ) );
}
if ( ! defined( 'FS_SDK__EXCEPTIONS_PATH' ) ) {
	define( 'FS_SDK__EXCEPTIONS_PATH', FS_SDK__PATH . '/Exceptions/' );
}

if ( ! function_exists( 'json_decode' ) ) {
	throw new Exception( 'Freemius needs the JSON PHP extension.' );
}

// Include all exception files.
$exceptions = array(
	'Exception',
	'InvalidArgumentException',
	'ArgumentNotExistException',
	'EmptyArgumentException',
	'OAuthException'
);

foreach ( $exceptions as $e ) {
	require_once FS_SDK__EXCEPTIONS_PATH . $e . '.php';
}

if ( class_exists( 'Freemius_Api_Base' ) ) {
	return;
}

abstract class Freemius_Api_Base {
	const VERSION = '1.0.4';
	const FORMAT = 'json';

	protected $_id;
	protected $_public;
	protected $_secret;
	protected $_scope;
	protected $_isSandbox;

	/**
	 * @param string $pScope 'app', 'developer', 'plugin', 'user' or 'install'.
	 * @param number $pID Element's id.
	 * @param string $pPublic Public key.
	 * @param string $pSecret Element's secret key.
	 * @param bool $pIsSandbox Whether or not to run API in sandbox mode.
	 */
	public function Init( $pScope, $pID, $pPublic, $pSecret, $pIsSandbox = false ) {
		$this->_id        = $pID;
		$this->_public    = $pPublic;
		$this->_secret    = $pSecret;
		$this->_scope     = $pScope;
		$this->_isSandbox = $pIsSandbox;
	}

	public function IsSandbox() {
		return $this->_isSandbox;
	}

	function CanonizePath( $pPath ) {
		$pPath     = trim( $pPath, '/' );
		$query_pos = strpos( $pPath, '?' );
		$query     = '';

		if ( false !== $query_pos ) {
			$query = substr( $pPath, $query_pos );
			$pPath = substr( $pPath, 0, $query_pos );
		}

		// Trim '.json' suffix.
		$format_length = strlen( '.' . self::FORMAT );
		$start         = $format_length * ( - 1 ); //negative
		if ( substr( strtolower( $pPath ), $start ) === ( '.' . self::FORMAT ) ) {
			$pPath = substr( $pPath, 0, strlen( $pPath ) - $format_length );
		}

		switch ( $this->_scope ) {
			case 'app':
				$base = '/apps/' . $this->_id;
				break;
			case 'developer':
				$base = '/developers/' . $this->_id;
				break;
			case 'user':
				$base = '/users/' . $this->_id;
				break;
			case 'plugin':
				$base = '/plugins/' . $this->_id;
				break;
			case 'install':
				$base = '/installs/' . $this->_id;
				break;
			default:
				throw new Freemius_Exception( 'Scope not implemented.' );
		}

		return '/v' . FS_API__VERSION . $base .
		       ( ! empty( $pPath ) ? '/' : '' ) . $pPath .
		       ( ( false === strpos( $pPath, '.' ) ) ? '.' . self::FORMAT : '' ) . $query;
	}

	abstract function MakeRequest( $pCanonizedPath, $pMethod = 'GET', $pParams = array() );

	/**
	 * @param string $pPath
	 * @param string $pMethod
	 * @param array $pParams
	 *
	 * @return object[]|object|null
	 */
	private function _Api( $pPath, $pMethod = 'GET', $pParams = array() ) {
		$pMethod = strtoupper( $pMethod );

		try {
			$result = $this->MakeRequest( $pPath, $pMethod, $pParams );
		} catch ( Freemius_Exception $e ) {
			// Map to error object.
			$result = (object) $e->getResult();
		} catch ( Exception $e ) {
			// Map to error object.
			$result = (object) array(
				'error' => array(
					'type'    => 'Unknown',
					'message' => $e->getMessage() . ' (' . $e->getFile() . ': ' . $e->getLine() . ')',
					'code'    => 'unknown',
					'http'    => 402
				)
			);
		}

		return $result;
	}

	public function Api( $pPath, $pMethod = 'GET', $pParams = array() ) {
		return $this->_Api( $this->CanonizePath( $pPath ), $pMethod, $pParams );
	}

	/**
	 * Base64 decoding that does not need to be urldecode()-ed.
	 *
	 * Exactly the same as PHP base64 encode except it uses
	 *   `-` instead of `+`
	 *   `_` instead of `/`
	 *   No padded =
	 *
	 * @param string $input Base64UrlEncoded() string
	 *
	 * @return string
	 */
	protected static function Base64UrlDecode( $input ) {
		/**
		 * IMPORTANT NOTE:
		 * This is a hack suggested by @otto42 and @greenshady from
		 * the theme's review team. The usage of base64 for API
		 * signature encoding was approved in a Slack meeting
		 * held on Tue (10/25 2016).
		 *
		 * @todo Remove this hack once the base64 error is removed from the Theme Check.
		 *
		 * @since 1.2.2
		 * @author Vova Feldman (@svovaf)
		 */
		$fn = 'base64' . '_decode';

		return $fn( strtr( $input, '-_', '+/' ) );
	}

	/**
	 * Base64 encoding that does not need to be urlencode()ed.
	 *
	 * Exactly the same as base64 encode except it uses
	 *   `-` instead of `+
	 *   `_` instead of `/`
	 *
	 * @param string $input string
	 *
	 * @return string Base64 encoded string
	 */
	protected static function Base64UrlEncode( $input ) {
		/**
		 * IMPORTANT NOTE:
		 * This is a hack suggested by @otto42 and @greenshady from
		 * the theme's review team. The usage of base64 for API
		 * signature encoding was approved in a Slack meeting
		 * held on Tue (10/25 2016).
		 *
		 * @todo Remove this hack once the base64 error is removed from the Theme Check.
		 *
		 * @since 1.2.2
		 * @author Vova Feldman (@svovaf)
		 */
		$fn  = 'base64' . '_encode';
		$str = strtr( $fn( $input ), '+/', '-_' );
		$str = str_replace( '=', '', $str );

		return $str;
	}
}
