<?php
	error_reporting(E_ALL);
	require 'settings.php';

	if ($password && (!isset($_SERVER['PHP_AUTH_PW']) || $_SERVER['PHP_AUTH_PW'] != $password)) {
		header('WWW-Authenticate: Basic realm="bbn"');
		header('HTTP/1.0 401 Unauthorized');
		echo '<p>Access denied.</p></body></html>';
		exit;
	}

	session_start();

	if (!isset($_SESSION['index']) || isset($_GET['reindex']) || empty($_SESSION['index']))
	{
		$files = glob($dir . '/*');
		usort($files, function($a, $b)
		{
			return filemtime($b) - filemtime($a);
		});
		$_SESSION['index'] = array_map(fn($value): string => str_replace('.md', '', $value), $files);
	}

	function download()
	{
		$zip = new ZipArchive();
		$zip_name = 'bbn.zip';
		$zip->open($zip_name,  ZipArchive::CREATE);
		foreach($_SESSION['index'] as $path)
		{
			if (!str_ends_with($path, '.del'))
			{
				$path = $path . '.md';
				if (file_exists($path))
				{
					$zip->addFile($path, basename($path));
				}
				else
				{
					echo"file does not exist";
				}
			}
		}
		$zip->close();

		header('Content-disposition: attachment; filename=' . $zip_name);
		header('Content-type: application/zip');
		readfile($zip_name);

		unlink($zip_name);
		exit;
	}

	function removefromindex($title)
	{
		global $dir;
		$key = array_search($dir . '/' . $title, $_SESSION['index']);
		if ($key !== FALSE)
		{
			array_splice($_SESSION['index'], $key, 1);
		}
	}

	function savenote($title, $content)
	{
		global $dir;
		$path = $dir . '/' . $title;
		$lastchanged = filemtime($path);
		$previous = $_POST['lastchanged'];
		if (!isset($_GET['clip']) && (int)$lastchanged > (int)$previous)
		{
			$tempcontent = file_get_contents($path . '.md');
			if ($tempcontent != $content)
			{
				$temptitle = $title . '_' . $lastchanged;
				file_put_contents($dir . '/' . $temptitle . '.md', $tempcontent);
				array_unshift($_SESSION['index'], $dir . '/' . $temptitle);
				echo '<div class="grey">Conflict detected. See backup: ' . $temptitle . '</div>';
			}
		}
		file_put_contents($path . '.md', $content);
		removefromindex($title);
		array_unshift($_SESSION['index'], $path);
	}

	function linksdiv($content)
	{
		$divcontent = '<div class="grey">';
		$links = array();
		if (preg_match_all('/\[\[(.*)\]\]/', $content, $links, PREG_SET_ORDER))
		{
			foreach($links as $link)
			{
				$divcontent .=  '<div>
				<a href="index.php?open=true&param=' . urlencode($link[1]) . '">' . $link[1] . '</a>
				</div>';
			}
		}
		$links = array();
		if (preg_match_all('/(https?:.*)\b/', $content, $links, PREG_SET_ORDER))
		{
			foreach($links as $link)
			{
				$divcontent .=  '<div>
				<a target="_blank" href="' . $link[1] . '">' . $link[1] . '</a>
				</div>';
			}
		}
		$divcontent .= '</div>';
		return $divcontent;
	}

	$nextpage = 'home';

	if (isset($_GET['download']))
	{
		download();
	}

	$preview = '';
	if (isset($_GET['clip']) && $_GET['param'])
	{
		$content = $_GET['param'] . "\r\n" . file_get_contents($dir . '/todo.md');
		savenote('todo', $content);
		$_GET['param'] = '';
	}
	else if (isset($_POST['save']) || isset($_POST['home']) || isset($_POST['links']) || isset($_POST['stats']))
	{
		$title = $_POST['title'];
		$content = $_POST['content'];
		savenote($title, $content);

		$previoustitle = $_POST['previoustitle'];
		if ($title != $previoustitle)
		{
			rename($dir . '/' . $previoustitle . '.md', $dir . '/' . $previoustitle . '.md.del');
			removefromindex($previoustitle);
		}

		if (!isset($_POST['home']))
		{
			$nextpage = 'note';
		}
	}
	else if (isset($_POST['delete']))
	{
		$title = $_POST['title'];
		rename($dir . '/' . $title . '.md', $dir . '/' . $title . '.md.del');
		removefromindex($title);
	}
	else if (isset($_POST['preview']))
	{
		require 'libs/Parsedown.php';
		$title = $_POST['title'];
		$content = $_POST['content'];
		$pos = 0;
		if (str_starts_with($content, '---'))
		{
			$pos = strpos($content, '---', 3) + 3;
		}
		$Parsedown = new Parsedown();
		$Parsedown->setBreaksEnabled(true);
		$preview = $Parsedown->text('# ' . $title . "\r\n" . substr($content, $pos));
		$nextpage = 'preview';
	}
	else if (isset($_GET['open']))
	{
		$nextpage = 'note';
		$title = $_GET['param'];
	}
?>

<!DOCTYPE html>
<html>
	<head>
		<title>
		<?php
			if ($nextpage != 'home' && isset($title))
			{
				echo $title;
			}
			else
			{
				echo 'bbn';
			}
		?>
		</title>
		<link rel="manifest" href="manifest.json" />
		<meta name="theme-color" content="white" />
		<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
		<meta charset="UTF-8">
		<link rel="stylesheet" type="text/css" href="style.css">
	</head>
	<body>

		<?php
			if ($nextpage == 'preview')
			{
				echo $preview;
			}
			else if ($nextpage == 'note')
			{
				$now = date("Y-m-d H.i.s", time());
				if (!$title)
				{
					$title = $now;
				}

				if (!file_exists($dir . '/' . $title . '.md'))
				{
					$content = "---\r\ndate: " . substr($now, 0, 10) . "\r\ntags: \r\n---\r\n";
					savenote($title, $content);
				}
				else if (!$content)
				{
					$content = file_get_contents($dir . '/' . $title . '.md');
				}

				clearstatcache();
				$lastchanged = filemtime($dir . '/' . $title . '.md');
				$lines = substr_count($content, "\r\n");
				$words = substr_count($content, " ") + $lines;
				$chars = strlen($content);

				$rows = max(20, $lines) * 2;

				require('note.php');

			}
			else if ($nextpage == 'home')
			{
				if (isset($_GET['param']))
				{
					$param = $_GET['param'];
				}
				require('home.php');

				echo '<div>';

				foreach($_SESSION['index'] as $path)
				{
					$tags = '';
					$name = basename($path);
					if (!str_ends_with($name, '.del'))
					{
						if (($_GET['param'] && isset($_GET['search'])) || isset($_GET['tags']))
						{
							$content = file_get_contents($path . '.md');
							if (
								// param does not match content or title
								(isset($_GET['search']) && !str_contains(strtolower($content), strtolower($param)) && !str_contains(strtolower($name), strtolower($param))) ||
								// param does not match tags
								(isset($_GET['tags']) && !preg_match('/tags:.*' . $param . '/i', $content))
							)
							{
								continue;
							}
							else if (isset($_GET['search']) && $param == $name)
							{
								header('Location: index.php?open=true&param=' . urlencode($name));
								die();
							}
						}
						echo '<div><a href=index.php?open=true&param=' . urlencode($name) . '>' . $name .'</a>';
						if (isset($content) && isset($_GET['tags']))
						{
							$tags = array();
							$hastags = preg_match_all('/tags:(.*)/i', $content, $tags, PREG_SET_ORDER);
							if ($hastags)
							{
								$tagslist = explode(',', $tags[0][1]);
								echo '<span class="grey"> ';
								foreach ($tagslist as $tag)
								{
									$tag = trim($tag);
									echo('<a class="grey" href="index.php?tags=true&param=' . $tag . '">' . $tag . '</a> ');
								}
								echo '</span>';
							}
						}
						else if (isset($_GET['search']) && str_contains(strtolower($content), strtolower($param)))
						{
							$pos = strpos(strtolower($content), strtolower($param));
							echo '<span class="grey"> ' . $param . substr($content, $pos + strlen($param), 42) . '</span>';
						}
						echo'</div>';
					}
				}

				echo '</div>';
			}
		?>
	</body>
</html>