<?php

namespace App\Message;

use Mustache_Engine;
use App\Config\Config;
use App\Message\Handler;
use Exception;

/**
* Base class for a message
*
* @author Phil Burton <phil@pgburton.com>
*/
class Base
{
    /**
     * Cache of the loaded config array
     *
     * @var string
     */
    protected $config;

    /**
     * The raw message string loaded from config
     *
     * @var string
     */
    protected $message;

    /**
     * The list of vars we need to inject
     *
     * @var array
     */
    protected $injects = [];

    /**
     * The array of important vars
     *
     * @var string
     */
    protected $important;

    /**
    * Load the message from the config
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    protected function loadMessage()
    {
        if (!array_key_exists($this->getName(), $this->config)) {
            throw new Exception('Could not load messge from config (' . $this->getName() . ')');
        }

        $this->message = $this->config[$this->getName()];
    }

    /**
    * Load the config
    */
    protected function loadConfig()
    {
        $config = Config::getConfig();

        if (!$config) {
            throw new Exception('Could not load config');
        }

        $this->config = $config;
    }

    /**
     * Get the name for this message, by default we use the class name
     *
     * @author Phil Burton <phil@pgburton.com>
     * @return string
     */
    public function getName()
    {
        $split = explode("\\", get_class($this));
        return strtolower($split[count($split) - 1]);
    }

    /**
    * Construct, load config and message
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    public function __construct(Handler $handler)
    {
        $this->loadConfig();

        $this->loadMessage();

        $this->setFromHandler($handler);
    }

    /**
    * Render the message, injecting any values into the message using mustache
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    public function renderMessage()
    {
        $m = new Mustache_Engine;
        return $m->render($this->message, $this->getInjectValues());
    }


    /**
    * Return the injected values
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    public function getInjectValues()
    {
        $out = [];
        foreach ($this->injects as $inject) {
            $out[$inject] = $this->$inject;
        }

        return $out;
    }

    /**
    * Get the important injected values
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    public function getImportantValues()
    {
        $out = [];
        foreach ($this->important as $important) {
            $out[$important] = $this->$important;
        }

        return $out;
    }

    /**
    * Set-up this message's inject values based on an input array
    *
    * @author Phil Burton <phil@pgburton.com>
    */
    public function setFromHandler(Handler $handler)
    {
        foreach ($handler->returnImportants() as $name) {
            if (in_array($name, $this->injects)) {
                $value = $handler->$name;

                if (isset($value) && $value) {
                    $this->$name = $value;
                }
            }
        }
    }
}