<?php
/**
 * Copyright 2011-2013 Anthon Pang. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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.
 *
 * @package WebDriver
 *
 * @author Anthon Pang <apang@softwaredevelopment.ca>
 */

namespace WebDriver;

use WebDriver\Exception as WebDriverException;

/**
 * WebDriver\Storage class
 *
 * @package WebDriver
 *
 * @method mixed getKey($key) Get key/value pair.
 * @method void deleteKey($key) Delete a specific key.
 * @method integer size() Get the number of items in the storage.
 */
abstract class Storage extends AbstractWebDriver
{
    /**
     * {@inheritdoc}
     */
    protected function methods()
    {
        return array(
            'key' => array('GET', 'DELETE'),
            'size' => array('GET'),
        );
    }

    /**
     * Get all keys from storage or a specific key/value pair
     *
     * @return mixed
     */
    public function get()
    {
        // get all keys
        if (func_num_args() === 0) {
            $result = $this->curl('GET', '');

            return $result['value'];
        }

        // get key/value pair
        if (func_num_args() === 1) {
            return $this->getKey(func_get_arg(0));
        }

        throw WebDriverException::factory(WebDriverException::UNEXPECTED_PARAMETERS);
    }

    /**
     * Set specific key/value pair
     *
     * @return \WebDriver\Storage
     *
     * @throw \WebDriver\Exception\UnexpectedParameters if unexpected parameters
     */
    public function set()
    {
        if (func_num_args() === 1
            && is_array($arg = func_get_arg(0))
        ) {
            $this->curl('POST', '', $arg);

            return $this;
        }

        if (func_num_args() === 2) {
            $arg = array(
                'key' => func_get_arg(0),
                'value' => func_get_arg(1),
            );
            $this->curl('POST', '', $arg);

            return $this;
        }

        throw WebDriverException::factory(WebDriverException::UNEXPECTED_PARAMETERS);
    }

    /**
     * Delete storage or a specific key
     *
     * @return \WebDriver\Storage
     *
     * @throw \WebDriver\Exception\UnexpectedParameters if unexpected parameters
     */
    public function delete()
    {
        // delete storage
        if (func_num_args() === 0) {
            $this->curl('DELETE', '');

            return $this;
        }

        // delete key from storage
        if (func_num_args() === 1) {
            return $this->deleteKey(func_get_arg(0));
        }

        throw WebDriverException::factory(WebDriverException::UNEXPECTED_PARAMETERS);
    }

    /**
     * Factory method to create Storage objects
     *
     * @param string $type 'local' or 'session' storage
     * @param string $url  URL
     *
     * @return \WebDriver\Storage
     */
    public static function factory($type, $url)
    {
        // dynamically define custom storage classes
        $className = ucfirst(strtolower($type));
        $namespacedClassName = __CLASS__ . '\\' . $className;

        if (!class_exists($namespacedClassName, false)) {
            eval(
                'namespace ' . __CLASS__ . '; final class ' . $className . ' extends \\' . __CLASS__ . '{}'
            );
        }

        return new $namespacedClassName($url);
    }
}
