<?php

/**
 * Vvveb
 *
 * Copyright (C) 2022  Ziadin Givan
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 */

/**
 * elFinder Plugin Normalizer
 * UTF-8 Normalizer of file-name and file-path etc.
 * nfc(NFC): Canonical Decomposition followed by Canonical Composition
 * nfkc(NFKC): Compatibility Decomposition followed by Canonical
 * This plugin require Class "Normalizer" (PHP 5 >= 5.3.0, PECL intl >= 1.0.0)
 * or PEAR package "I18N_UnicodeNormalizer"
 * ex. binding, configure on connector options
 *    $opts = array(
 *        'bind' => array(
 *            'upload.pre mkdir.pre mkfile.pre rename.pre archive.pre ls.pre' => array(
 *                'Plugin.Normalizer.cmdPreprocess'
 *            ),
 *            'upload.presave paste.copyfrom' => array(
 *                'Plugin.Normalizer.onUpLoadPreSave'
 *            )
 *        ),
 *        // global configure (optional)
 *        'plugin' => array(
 *            'Normalizer' => array(
 *                'enable'    => true,
 *                'nfc'       => true,
 *                'nfkc'      => true,
 *                'umlauts'   => false,
 *                'lowercase' => false,
 *                'convmap'   => array()
 *            )
 *        ),
 *        // each volume configure (optional)
 *        'roots' => array(
 *            array(
 *                'driver' => 'LocalFileSystem',
 *                'path'   => '/path/to/files/',
 *                'URL'    => 'http://localhost/to/files/'
 *                'plugin' => array(
 *                    'Normalizer' => array(
 *                        'enable'    => true,
 *                        'nfc'       => true,
 *                        'nfkc'      => true,
 *                        'umlauts'   => false,
 *                        'lowercase' => false,
 *                        'convmap'   => array()
 *                    )
 *                )
 *            )
 *        )
 *    );.
 *
 * @package elfinder
 * @author  Naoki Sawada
 * @license New BSD
 */
class elFinderPluginNormalizer extends elFinderPlugin {
	private $replaced = [];

	private $keyMap = [
		'ls'     => 'intersect',
		'upload' => 'renames',
		'mkdir'  => ['name', 'dirs'],
	];

	public function __construct($opts) {
		$defaults = [
			'enable'    => true,  // For control by volume driver
			'nfc'       => true,  // Canonical Decomposition followed by Canonical Composition
			'nfkc'      => true,  // Compatibility Decomposition followed by Canonical
			'umlauts'   => false, // Convert umlauts with their closest 7 bit ascii equivalent
			'lowercase' => false, // Make chars lowercase
			'convmap'   => [], // Convert map ('FROM' => 'TO') array
		];

		$this->opts = array_merge($defaults, $opts);
	}

	public function cmdPreprocess($cmd, &$args, $elfinder, $volume) {
		$opts = $this->getCurrentOpts($volume);

		if (! $opts['enable']) {
			return false;
		}
		$this->replaced[$cmd] = [];
		$key                  = (isset($this->keyMap[$cmd])) ? $this->keyMap[$cmd] : 'name';

		if (is_array($key)) {
			$keys = $key;
		} else {
			$keys = [$key];
		}

		foreach ($keys as $key) {
			if (isset($args[$key])) {
				if (is_array($args[$key])) {
					foreach ($args[$key] as $i => $name) {
						if ($cmd === 'mkdir' && $key === 'dirs') {
							// $name need '/' as prefix see #2607
							$name   = '/' . ltrim($name, '/');
							$_names = explode('/', $name);
							$_res   = [];

							foreach ($_names as $_name) {
								$_res[] = $this->normalize($_name, $opts);
							}
							$this->replaced[$cmd][$name] = $args[$key][$i] = join('/', $_res);
						} else {
							$this->replaced[$cmd][$name] = $args[$key][$i] = $this->normalize($name, $opts);
						}
					}
				} else {
					if ($args[$key] !== '') {
						$name                        = $args[$key];
						$this->replaced[$cmd][$name] = $args[$key] = $this->normalize($name, $opts);
					}
				}
			}
		}

		if ($cmd === 'ls' || $cmd === 'mkdir') {
			if (! empty($this->replaced[$cmd])) {
				// un-regist for legacy settings
				$elfinder->unbind($cmd, [$this, 'cmdPostprocess']);
				$elfinder->bind($cmd, [$this, 'cmdPostprocess']);
			}
		}

		return true;
	}

	public function cmdPostprocess($cmd, &$result, $args, $elfinder, $volume) {
		if ($cmd === 'ls') {
			if (! empty($result['list']) && ! empty($this->replaced['ls'])) {
				foreach ($result['list'] as $hash => $name) {
					if ($keys = array_keys($this->replaced['ls'], $name)) {
						if (count($keys) === 1) {
							$result['list'][$hash] = $keys[0];
						} else {
							$result['list'][$hash] = $keys;
						}
					}
				}
			}
		} else {
			if ($cmd === 'mkdir') {
				if (! empty($result['hashes']) && ! empty($this->replaced['mkdir'])) {
					foreach ($result['hashes'] as $name => $hash) {
						if ($keys = array_keys($this->replaced['mkdir'], $name)) {
							$result['hashes'][$keys[0]] = $hash;
						}
					}
				}
			}
		}
	}

	// NOTE: $thash is directory hash so it unneed to process at here
	public function onUpLoadPreSave(&$thash, &$name, $src, $elfinder, $volume) {
		$opts = $this->getCurrentOpts($volume);

		if (! $opts['enable']) {
			return false;
		}

		$name = $this->normalize($name, $opts);

		return true;
	}

	protected function normalize($str, $opts) {
		if ($opts['nfc'] || $opts['nfkc']) {
			if (class_exists('Normalizer', false)) {
				if ($opts['nfc'] && ! Normalizer::isNormalized($str, Normalizer::FORM_C)) {
					$str = Normalizer::normalize($str, Normalizer::FORM_C);
				}

				if ($opts['nfkc'] && ! Normalizer::isNormalized($str, Normalizer::FORM_KC)) {
					$str = Normalizer::normalize($str, Normalizer::FORM_KC);
				}
			} else {
				if (! class_exists('I18N_UnicodeNormalizer', false)) {
					if (is_readable('I18N/UnicodeNormalizer.php')) {
						include_once 'I18N/UnicodeNormalizer.php';
					} else {
						trigger_error('Plugin Normalizer\'s options "nfc" or "nfkc" require PHP class "Normalizer" or PEAR package "I18N_UnicodeNormalizer"', E_USER_WARNING);
					}
				}

				if (class_exists('I18N_UnicodeNormalizer', false)) {
					$normalizer = new I18N_UnicodeNormalizer();

					if ($opts['nfc']) {
						$str = $normalizer->normalize($str, 'NFC');
					}

					if ($opts['nfkc']) {
						$str = $normalizer->normalize($str, 'NFKC');
					}
				}
			}
		}

		if ($opts['umlauts']) {
			if (strpos($str = htmlentities($str, ENT_QUOTES, 'UTF-8'), '&') !== false) {
				$str = html_entity_decode(preg_replace('~&([a-z]{1,2})(?:acute|caron|cedil|circ|grave|lig|orn|ring|slash|tilde|uml);~i', '$1', $str), ENT_QUOTES, 'utf-8');
			}
		}

		if ($opts['convmap'] && is_array($opts['convmap'])) {
			$str = strtr($str, $opts['convmap']);
		}

		if ($opts['lowercase']) {
			if (function_exists('mb_strtolower')) {
				$str = mb_strtolower($str, 'UTF-8');
			} else {
				$str = strtolower($str);
			}
		}

		return $str;
	}
}
