<?php

class UOJBlogEditor {
	public $type = 'blog';
	public $name;
	public $blog_url;
	public $save;
	public $cur_data = [];
	public $post_data = [];
	public $show_editor = true;
	public $show_tags = true;

	public $label_text = [
		'title' => '标题',
		'tags' => '标签（多个标签用逗号隔开）',
		'content' => '内容',
		'view blog' => '查看博客',
		'blog visibility' => '博客可见性',
		'private' => '未公开',
		'public' => '公开'
	];

	public $validator = array();

	function __construct() {
		global $REQUIRE_LIB;
		$REQUIRE_LIB['blog-editor'] = '';

		$this->validator = [
			'title' => function (&$title) {
				if ($title == '') {
					return '标题不能为空';
				}
				if (strlen($title) > 100) {
					return '标题不能超过 100 个字节';
				}
				if (HTML::escape($title) === '') {
					return '无效编码';
				}
				return '';
			},
			'content_md' => function (&$content_md) {
				if (strlen($content_md) > 1000000) {
					return '内容过长';
				}
				return '';
			},
			'tags' => function (&$tags) {
				$tags = str_replace('，', ',', $tags);
				$tags_raw = explode(',', $tags);
				if (count($tags_raw) > 10) {
					return '标签个数不能超过10';
				}
				$tags = array();
				foreach ($tags_raw as $tag) {
					$tag = trim($tag);
					if (strlen($tag) == 0) {
						continue;
					}
					if (strlen($tag) > 30) {
						return '标签 “' . HTML::escape($tag) . '” 太长';
					}
					if (in_array($tag, $tags, true)) {
						return '标签 “' . HTML::escape($tag) . '” 重复出现';
					}
					$tags[] = $tag;
				}
				return '';
			}
		];
	}

	public function validate($name) {
		if (!isset($_POST["{$this->name}_{$name}"])) {
			return '不能为空';
		}
		$this->post_data[$name] = $_POST["{$this->name}_{$name}"];
		$val = $this->validator[$name];
		return $val($this->post_data[$name]);
	}
	private function receivePostData() {
		$errors = array();

		$keys = array('title');
		if ($this->show_tags) {
			$keys[] = 'tags';
		}
		if ($this->show_editor) {
			$keys[] = 'content_md';
		}
		foreach ($keys as $name) {
			$cur_err = $this->validate($name);
			if ($cur_err) {
				$errors[$name] = $cur_err;
			}
		}
		if ($errors) {
			die(json_encode($errors));
		}
		crsf_defend();

		$this->post_data['is_hidden'] = isset($_POST["{$this->name}_is_hidden"]) ? 1 : 0;

		$purifier = HTML::purifier();
		$parsedown = HTML::parsedown();

		$this->post_data['title'] = HTML::escape($this->post_data['title']);

		if ($this->show_editor) {
			if ($this->type == 'blog') {
				$this->post_data['content'] = $parsedown->text($this->post_data['content_md']);

				if (preg_match('/^.*<!--.*readmore.*-->.*$/m', $this->post_data['content'], $matches, PREG_OFFSET_CAPTURE)) {
					$content_less = substr($this->post_data['content'], 0, $matches[0][1]);
					$content_more = substr($this->post_data['content'], $matches[0][1] + strlen($matches[0][0]));
					$this->post_data['content'] = $purifier->purify($content_less) . '<!-- readmore -->' . $purifier->purify($content_more);
				} else {
					$this->post_data['content'] = $purifier->purify($this->post_data['content']);
				}
			} elseif ($this->type == 'slide') {
				$content_array = yaml_parse($this->post_data['content_md']);
				if ($content_array === false || !is_array($content_array)) {
					die(json_encode(array('content_md' => '不合法的 YAML 格式')));
				}

				$marked = function ($md) use ($parsedown, $purifier) {
					$dom = new DOMDocument;
					$dom->loadHTML(mb_convert_encoding($parsedown->text($md), 'HTML-ENTITIES', 'UTF-8'));
					$elements = $dom->getElementsByTagName('li');

					foreach ($elements as $element) {
						$element->setAttribute(
							'class',
							$element->getAttribute('class') . ' fragment'
						);
					}

					return $purifier->purify($dom->saveHTML());
				};

				$config = array();
				$this->post_data['content'] = '';
				foreach ($content_array as $slide_name => $slide_content) {
					if (is_array($slide_content) && is_array($slide_content['config'])) {
						foreach (array('theme') as $config_key) {
							if (is_string($slide_content['config'][$config_key]) && strlen($slide_content['config'][$config_key]) <= 30) {
								$config[$config_key] = $slide_content['config'][$config_key];
							}
						}
						continue;
					}

					$this->post_data['content'] .= '<section>';

					if (is_string($slide_content)) {
						$this->post_data['content'] .= $marked($slide_content);
					} elseif (is_array($slide_content)) {
						if (is_array($slide_content['children'])) {
							foreach ($slide_content['children'] as $cslide_name => $cslide_content) {
								$this->post_data['content'] .= '<section>';
								$this->post_data['content'] .= $marked($cslide_content);
								$this->post_data['content'] .= '</section>';
							}
						}
					}
					$this->post_data['content'] .= "</section>\n";
				}
				$this->post_data['content'] = json_encode($config) . "\n" . $this->post_data['content'];
			}
		}
	}

	public function handleSave() {
		global $REQUIRE_LIB;

		$save = $this->save;
		$this->receivePostData();
		$ret = $save($this->post_data);
		if (!$ret) {
			$ret = array();
		}

		if (isset($_POST['need_preview'])) {
			ob_start();
			if ($this->type == 'blog') {
				$req_lib = [
					'mathjax' => '',
					'pdf.js' => '',
				];

				if (isset($REQUIRE_LIB['bootstrap5'])) {
					$req_lib['bootstrap5'] = '';
					$req_lib['hljs'] = '';
				} else {
					$req_lib['shjs'] = '';
				}

				echoUOJPageHeader('博客预览', array('ShowPageHeader' => false, 'REQUIRE_LIB' => $req_lib));
				if (!isset($REQUIRE_LIB['bootstrap5'])) {
					echo '<link rel="stylesheet" type="text/css" href="' . HTML::url('/css/markdown.css') . '">';
				}
				echo '<article class="markdown-body">';
				echo $this->post_data['content'];
				echo '</article>';
				echoUOJPageFooter(array('ShowPageFooter' => false));
			} elseif ($this->type == 'slide') {
				uojIncludeView('slide', array_merge(
					UOJContext::pageConfig(),
					[
						'PageTitle' => '幻灯片预览',
						'content' => $this->post_data['content']
					]
				));
			}
			$ret['html'] = ob_get_contents();
			ob_end_clean();
		}

		die(json_encode($ret));
	}

	public function runAtServer() {
		if (isset($_POST["save-{$this->name}"])) {
			$this->handleSave();
		}
	}
	public function printHTML() {
		global $REQUIRE_LIB;

		uojIncludeView('blog-editor', ['editor' => $this, 'REQUIRE_LIB' => $REQUIRE_LIB]);
	}
}