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<?php

/**
 * Copyright 2013 Aaron Scherer
 *
 * 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.
 *
 * @copyright   Aaron Scherer 2013
 * @license     Apache License, Version 2.0
 */

use Symfony\Component\Console\Input\ArgvInput;


/**
 * Environment Class
 * 
 * @author Aaron Scherer <aequasi@gmail.com
 */
class Environment
{

    /**
     * @var string[]
     */
    static public $allowedEnvironments = array(
        'dev',
        'test',
        'staging',
        'prod'
    );

    /**
     * @var ArgvInput
     */
    public $input = null;

    /**
     * @var string
     */
    private $environment = false;

    /**
     * @var Boolean
     */
    private $debug = false;

    /**
     * Sets the $environment and $debug values. Checks for $_GET[ 'SYM_ENV' ],
     * Then checks for the Apache SYM_ENV
     *
     * @param ArgvInput $input
     */
    public function __construct(ArgvInput $input = null)
    {
        $cfgEnv = get_cfg_var('symfony.environment');
        if ($cfgEnv !== false && !isset($_SERVER['SYM_ENV'])) {
            $_SERVER['SYM_ENV'] = $cfgEnv;
        }

        if (null !== $input) {
            $this->input = $input;
        }

        $this->environment = $this->findEnvironment();
        $this->checkEnvironment();

        $this->debug = $this->findDebug();
    }

    /**
     * @return string
     */
    private function findEnvironment()
    {
        if (null !== $this->input) {
            $env = $this->input->getParameterOption(array('--env', '-e'));
            if (!empty($env)) {
                return $env;
            }
        }

        if (isset($_SERVER['SYM_ENV'])) {
            return $_SERVER['SYM_ENV'];
        }

        return 'dev';
    }

    /**
     * @return Boolean
     * @throws \Exception
     */
    private function checkEnvironment()
    {
        if (!in_array($this->environment, self::$allowedEnvironments)) {
            throw new \Exception(sprintf(
                "`%s` is not a valid environment. Expected: %s",
                $this->environment,
                implode(', ', self::$allowedEnvironments)
            ));
        }

        return true;
    }

    /**
     * @return Boolean
     */
    private function findDebug()
    {
        if (null !== $this->input && !$this->input->hasParameterOption(array('--no-debug', ''))) {
            return true;
        }
        if (in_array($this->environment, ['dev', 'test'])) {
            return true;
        }

        return false;
    }

    /**
     * @return Boolean
     */
    public function getDebug()
    {
        return $this->debug;
    }

    /**
     * @return string
     */
    public function getEnvironment()
    {
        return $this->environment;
    }
}