lister.php

<?php /* Chronicle.md - Copyright (C) 2013 Bruce Alderson */

/* Chronicle (Dave) Lister

	Lists files, possibly caching the results.

*/
class lister {

	static $files;
	static $in;

	/* List the files in a folder, including metadata */
	static function folder($in, $url, $page = 0, $pageSize = 0, $sort) {

		$at = 0;
		$files = '';
		$start = $page * $pageSize;
		$end = $start + $pageSize;

		$url = preg_replace('#(?:page/[\d]+(?:/|))#', '', $url);

		$list = lister::files($in, $sort); // get the list of files in this root

		// generate the list of files in this follder, given the page and page size

		$c = count($list);
		$end = $c >= $end ? $end : $c;

		for ( $at = $start; $at < $end; $at++ )
			$files[] = $list[$at];

		// determine the paged links

		$prevLink = ($page != 0) ? "$url/page/" . sprintf('%d', $page - 1) : '';
		$nextLink = ($c >= $end) ? "$url/page/" . sprintf('%d', $page + 1) : '';

		// build a struct for the caller

		$folder = (object) array(
			'in'	=> $in,
			'url'	=> $url,
			'files' => $files,
			'prev'	=> preg_replace('/(\/+)/','/', $prevLink),
			'next'	=> preg_replace('/(\/+)/','/', $nextLink)
		);

		return $folder;
	}

	/* Get navigation relative to $url */
	static function relativeNav($in, $at, $base) {

		// scan posts and get next and prev URIs
		$path = lister::basefrom($at, $base); 	// get base folder
		$list = lister::files($path);			// scan from base folder
		$idx = array_search($at, $list); // find current post

		$prevLink = ''; $nextLink = '';

		if ($idx > 0)
			$prevLink = lister::urlize("$base/". $list[ $idx - 1 ], $base);

		if ($idx < count($list))
			$nextLink = lister::urlize("$base/". $list[ $idx + 1 ], $base);

		return (object) array(
			'in'	=> $in,
			'files'	=> $list,
			'prev'	=> lister::relativePath($prevLink),
			'next'	=> lister::relativePath($nextLink)
		);

	}

	/* Turn a path into a URL based on a pivot (root md file folder) */
	static function urlize($path, $pivot) {
		$parts = explode($pivot, $path);
		if (count($parts) < 3) return '';
		return preg_replace( '/(\/+)/', '/', $pivot.$parts[2] );
	}
	/* Turn a path into a base path based on a pivot (root md folder) */
	static function basefrom($path, $pivot) {
		$parts = explode($pivot, $path);
		return preg_replace( '/(\/+)/', '/', $parts[0].$pivot );
	}

	static function relativePath($p) {
		return preg_replace('#[\/]+#', '/', "/$p");
	}
	/* File list access (cached)

		Allows a file listing to be cached for a given root
	*/
	static function files($in, $sort = null) {
		if (empty(lister::$files) || (!empty(lister::$in) && lister::$in != $in)) {
			lister::$files = array_reverse(lister::directory($in));
		}
		// Assign a date function if sort is set and valid
		if ($sort === 'modified') $dateFunc = 'filemtime';
		if (isset($dateFunc)) {
			$sorted = array();
			foreach (lister::$files as $file) {
				$time = $dateFunc($file);
				if (count($sorted) === 0) // If first element, just add it
					$sorted[] = $file;
				else {
					$length = count($sorted) - 1;
					for ($i = $length; $i > -1; $i--) {
						if ($dateFunc($sorted[$i]) < $time) { // If this is newer, insert
							array_splice($sorted, $i, 0, $file);
						} else if (!in_array($file, $sorted)) { // add if not present
							$sorted[] = $file;
						}
					}
				}
			}
			return array_values(array_unique($sorted));
		} else { // No sort option was set, so return the default set of files
			return lister::$files;
		}
	}

	/* Get a directory listing  (recursive) */
	static function directory($d, $g = "*") {
		$files = array();
		$scan  = glob(rtrim($d, '/') . '/' . $g);

		if (is_file($d))
			array_push($files, $d);
		elseif (is_dir($d)) foreach ($scan as $path)
			$files = array_merge($files, lister::directory($path, $g));

		return $files;
	}
}