<?php

namespace Mews\Purifier;

/**
 * Laravel 5 HTMLPurifier package
 *
 * @copyright Copyright (c) 2015 MeWebStudio
 * @version   2.0.0
 * @author    Muharrem ERİN
 * @contact me@mewebstudio.com
 * @web http://www.mewebstudio.com
 * @date      2014-04-02
 * @license   MIT
 */

use Exception;
use HTMLPurifier;
use HTMLPurifier_Config;
use HTMLPurifier_HTMLDefinition;
use Illuminate\Contracts\Config\Repository;
use Illuminate\Filesystem\Filesystem;

class Purifier
{

    /**
     * @var Filesystem
     */
    protected $files;

    /**
     * @var Repository
     */
    protected $config;

    /**
     * @var HTMLPurifier
     */
    protected $purifier;

    /**
     * Constructor
     *
     * @param Filesystem $files
     * @param Repository $config
     * @throws Exception
     */
    public function __construct(Filesystem $files, Repository $config)
    {
        $this->files = $files;
        $this->config = $config;

        $this->setUp();
    }

    /**
     * Setup
     *
     * @throws Exception
     */
    private function setUp()
    {
        if (!$this->config->has('purifier')) {
            throw new Exception('Configuration parameters not loaded!');
        }

        $this->checkCacheDirectory();

        // Create a new configuration object
        $config = $this->getConfig();

        // Create HTMLPurifier object
        $this->purifier = new HTMLPurifier($config);
    }

    /**
     * Add a custom definition
     *
     * @see http://htmlpurifier.org/docs/enduser-customize.html
     * @param array $definitionConfig
     * @param HTMLPurifier_Config $configObject Defaults to using default config
     *
     * @return HTMLPurifier_Config $configObject
     */
    private function addCustomDefinition(array $definitionConfig, HTMLPurifier_Config $configObject = null)
    {
        if (!$configObject) {
            $configObject = HTMLPurifier_Config::createDefault();
            $configObject->loadArray($this->getConfig());
        }

        // Setup the custom definition
        $configObject->set('HTML.DefinitionID', $definitionConfig['id']);
        $configObject->set('HTML.DefinitionRev', $definitionConfig['rev']);

        // Enable debug mode
        if (!isset($definitionConfig['debug']) || $definitionConfig['debug']) {
            $configObject->set('Cache.DefinitionImpl', null);
        }

        // Start configuring the definition
        if ($def = $configObject->maybeGetRawHTMLDefinition()) {
            // Create the definition attributes
            if (!empty($definitionConfig['attributes'])) {
                $this->addCustomAttributes($definitionConfig['attributes'], $def);
            }

            // Create the definition elements
            if (!empty($definitionConfig['elements'])) {
                $this->addCustomElements($definitionConfig['elements'], $def);
            }
        }

        return $configObject;
    }

    /**
     * Add provided attributes to the provided definition
     *
     * @param array $attributes
     * @param HTMLPurifier_HTMLDefinition $definition
     *
     * @return HTMLPurifier_HTMLDefinition $definition
     */
    private function addCustomAttributes(array $attributes, HTMLPurifier_HTMLDefinition $definition)
    {
        foreach ($attributes as $attribute) {
            // Get configuration of attribute
            $required = !empty($attribute[3]) ? true : false;
            $onElement = $attribute[0];
            $attrName = $required ? $attribute[1] . '*' : $attribute[1];
            $validValues = $attribute[2];

            if ($onElement === '*') {
                $def = $validValues;
                if (is_string($validValues)) {
                    $def = new $validValues();
                }

                if ($def instanceof \HTMLPurifier_AttrDef) {
                    $definition->info_global_attr[$attrName] = $def;
                }

                continue;
            }

            $definition->addAttribute($onElement, $attrName, $validValues);
        }

        return $definition;
    }

    /**
     * Add provided elements to the provided definition
     *
     * @param array $elements
     * @param HTMLPurifier_HTMLDefinition $definition
     *
     * @return HTMLPurifier_HTMLDefinition $definition
     */
    private function addCustomElements(array $elements, HTMLPurifier_HTMLDefinition $definition)
    {
        foreach ($elements as $element) {
            // Get configuration of element
            $name = $element[0];
            $contentSet = $element[1];
            $allowedChildren = $element[2];
            $attributeCollection = $element[3];
            $attributes = isset($element[4]) ? $element[4] : null;

            if (!empty($attributes)) {
                $definition->addElement($name, $contentSet, $allowedChildren, $attributeCollection, $attributes);
            } else {
                $definition->addElement($name, $contentSet, $allowedChildren, $attributeCollection);
            }
        }
    }

    /**
     * Check/Create cache directory
     */
    private function checkCacheDirectory()
    {
        $cachePath = $this->config->get('purifier.cachePath');

        if ($cachePath) {
            if (!$this->files->isDirectory($cachePath)) {
                $this->files->makeDirectory($cachePath, $this->config->get('purifier.cacheFileMode', 0755),true);
            }
        }
    }

    /**
     * @param null $config
     *
     * @return mixed|null
     */
    protected function getConfig($config = null)
    {
        // Create a new configuration object
        $configObject = HTMLPurifier_Config::createDefault();

        // Allow configuration to be modified
        if (! $this->config->get('purifier.finalize')) {
            $configObject->autoFinalize = false;
        }

        // Set default config
        $defaultConfig = [];
        $defaultConfig['Core.Encoding'] = $this->config->get('purifier.encoding');
        $defaultConfig['Cache.SerializerPath'] = $this->config->get('purifier.cachePath');
        $defaultConfig['Cache.SerializerPermissions'] = $this->config->get('purifier.cacheFileMode', 0755);

        if (! $config) {
            $config = $this->config->get('purifier.settings.default');
        } elseif (is_string($config)) {
            $config = $this->config->get('purifier.settings.' . $config);
        }

        if (! is_array($config)) {
            $config = [];
        }

        // Merge configurations
        $config = $defaultConfig + $config;

        // Load to Purifier config
        $configObject->loadArray($config);

        // Load custom definition if set
        if ($definitionConfig = $this->config->get('purifier.settings.custom_definition')) {
            $this->addCustomDefinition($definitionConfig, $configObject);
        }

        // Load custom elements if set
        if ($elements = $this->config->get('purifier.settings.custom_elements')) {
            if ($def = $configObject->maybeGetRawHTMLDefinition()) {
                $this->addCustomElements($elements, $def);
            }
        }

        // Load custom attributes if set
        if ($attributes = $this->config->get('purifier.settings.custom_attributes')) {
            if ($def = $configObject->maybeGetRawHTMLDefinition()) {
                $this->addCustomAttributes($attributes, $def);
            }
        }

        return $configObject;
    }

    /**
     * @param      $dirty
     * @param null $config
     * @param \Closure|null $postCreateConfigHook
     * @return mixed
     */
    public function clean($dirty, $config = null, \Closure $postCreateConfigHook = null)
    {
        if (is_array($dirty)) {
            return array_map(function ($item) use ($config) {
                return $this->clean($item, $config);
            }, $dirty);
        }

        $configObject = null;
        if ($config !== null) {
            $configObject = $this->getConfig($config);

            if ($postCreateConfigHook !== null) {
                $postCreateConfigHook->call($this, $configObject);
            }
        }

        return $this->purifier->purify($dirty, $configObject);
    }

    /**
     * Get HTMLPurifier instance.
     *
     * @return \HTMLPurifier
     */
    public function getInstance()
    {
        return $this->purifier;
    }
}
