<?php
/* PageClasses.diff.class.php - phpgitweb
 * Copyright (C) 2011-2012  Philipp Kreil (pk910)
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License 
 * along with this program. If not, see <http://www.gnu.org/licenses/>. 
 */

class diff {
	private $commit, $tree, $diff, $data = array();
	
	public function __construct($commit, $tree, $diff) {
		$this->commit = $commit;
		$this->tree = $tree;
		$this->diff = $diff;
	}
	
	public static function generate_html($commit, $diff_data) {
		$diff_id = 0;
		$patch_id = 1;
		$html = array();
		foreach($diff_data['tree'] as $tree) {
			do {
				if(array_key_exists($diff_id, $diff_data['diffs']))
					$diff = $diff_data['diffs'][$diff_id];
				else
					$diff = null;
				if($diff && preg_match('/^diff --git (\"(?:[^\\\"]*(?:\\.[^\\\"]*)*)\"|[^ "]*) (.*)$/i', $diff[0], $matches))
					$to_file = $matches[2];
				else if($diff && preg_match('/^diff --(cc|combined) ("?.*"?)$/i', $diff[0], $matches))
					$to_file = $matches[2];
				else
					$to_file = null;
				if(!$to_file || strtolower($to_file) != $tree['to_file']) {
					if($tree['parents'] > 1) {
						//jump over missing diffs
						$diffobj = new diff($commit, $tree, null);
						$html[] = $diffobj->gen_contentprovider($patch_id);
						$patch_id++;
						break;
					}
					if(!$to_file)
						break;
				}
				$diffobj = new diff($commit, $tree, $diff);
				$html[] = $diffobj->gen_contentprovider($patch_id);
				$diff_id++;
				do {
					if(!array_key_exists($diff_id, $diff_data['diffs']))
						break;
					$diff = $diff_data['diffs'][$diff_id];
					if(preg_match('/^diff --git (\"(?:[^\\\"]*(?:\\.[^\\\"]*)*)\"|[^ "]*) (.*)$/i', $diff[0], $matches))
						$to_file = $matches[2];
					else if(preg_match('/^diff --(cc|combined) ("?.*"?)$/i', $diff[0], $matches))
						$to_file = $matches[2];
					else
						break;
					if(!array_key_exists('to_file', $tree))
						$tree['to_file'] = $tree['file'];
					if(strtolower($to_file) != $tree['to_file']) 
						break;
					$diffobj = new diff($commit, $tree, $diff);
					$html[] = $diffobj->gen_contentprovider(null);
					$diff_id++;
				} while(true);
				$patch_id++;
				break;
			} while(true);
		}
		if($patch_id == 1) {
			if(count($commit['parent']) > 1)
				$html[] = new ContentProvider('commitdiff', 'patch_nopatch_merge');
			else
				$html[] = new ContentProvider('commitdiff', 'patch_nopatch_simple');
		}
		return $html;
	}
	
	private function gen_diffcmd_header() {
		$header = array();
		if(!$this->diff) {
			$header[] = "diff --cc ";
			$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['id'], 'file' => $this->tree['to_file'], 'path' => ''));
		} else if($this->tree['parents'] > 1) {
			preg_match('!^(diff (.*?) )"?.*$!', $this->diff[0], $match);
			$header[] = $match[1];
			if(preg_match('/^[0]{40}$/', $this->tree['to_id']))
				$header[] = $this->tree['to_file'];
			else
				$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['id'], 'file' => $this->tree['to_file'], 'path' => ''));
		} else {
			preg_match('!^(diff (.*?) )"?a/.*$!', $this->diff[0], $match);
			$header[] = $match[1];
			if(preg_match('/^[0]{40}$/', $this->tree['from_id']))
				$header[] = 'a/'.$this->tree['file'];
			else
				$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['parent'][0], 'file' => $this->tree['from_file'], 'path' => 'a/'));
			$header[] = ' ';
			if(preg_match('/^[0]{40}$/', $this->tree['to_id']))
				$header[] = 'b/'.$this->tree['file'];
			else
				$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['id'], 'file' => $this->tree['to_file'], 'path' => 'b/'));
		}
		return $header;
	}
	
	private function gen_index_header($line) {
		$header = array();
		if(preg_match('/^((copy|rename) from ).*$/', $line, $matches)) {
			$header[] = $matches[1];
			if(array_key_exists('copy', $this->data))
				$this->data['copy']++;
			else
				$this->data['copy'] = 0;
			$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['parent'][$this->data['copy']], 'file' => $this->tree['from_file'], 'path' => ''));
		} else if(preg_match('/^((copy|rename) to ).*$/', $line, $matches)) {
			$header[] = $matches[1];
			$header[] = new ContentProvider('commitdiff', 'patch_link_blob', array('hash' => $this->commit['id'], 'file' => $this->tree['to_file'], 'path' => ''));
		} else if(preg_match('/^(index )[0-9a-fA-F]{40},[0-9a-fA-F]{40}/', $line, $matches)) { //combined diff
			$header[] = $matches[1];
			$parent_id = 0;
			foreach($this->tree['from_id'] as $from_id) {
				if($parent_id)
					$header[] = ',';
				if(preg_match('/^[0]{40}$/', $from_id))
					$header[] = '0000000';
				else
					$header[] = new ContentProvider('commitdiff', 'patch_link_blob_id', array('hash' => $this->commit['parent'][$parent_id], 'file' => $this->tree['from_file'], 'id' => substr($from_id, 0, 7)));
				$parent_id++;
			}
		} else if(preg_match('/^(index )([0-9a-fA-F]{40})..([0-9a-fA-F]{40})/', $line, $matches)) {
			$header[] = $matches[1];
			if(preg_match('/^[0]{40}$/', $matches[2]))
				$header[] = '0000000';
			else
				$header[] = new ContentProvider('commitdiff', 'patch_link_blob_id', array('hash' => $this->commit['parent'][0], 'file' => $this->tree['from_file'], 'id' => substr($matches[2], 0, 7)));
			$header[] = '..';
			if(preg_match('/^[0]{40}$/', $matches[3]))
				$header[] = '0000000';
			else
				$header[] = new ContentProvider('commitdiff', 'patch_link_blob_id', array('hash' => $this->commit['id'], 'file' => $this->tree['to_file'], 'id' => substr($matches[3], 0, 7)));
		} else
			$header[] = $line;
		if(preg_match('/([0-7]{6})$/', $line, $matches)) {
			$ftype = Tools::get_filetype($matches[1], true);
			$header[] = new ContentProvider('commitdiff', 'patch_fileinfo', array('info' => $ftype));
		}
		return $header;
	}
	
	private function format_line($line) {
		$lineobj = new ContentProvider('commitdiff', 'patch_diffline');
		$class = "";
		if($this->tree['parents'] > 1) {
			$prefix = substr($line, 0, $this->tree['parents']);
			if(preg_match('/@/', $prefix))
				$class = " chunk_header";
			else if(preg_match('/\\/', $prefix))
				$class = " incomplete";
			else if(preg_match('/+/', $prefix))
				$class = " add";
			else if(preg_match('/-/', $prefix))
				$class = " rem";
		} else {
			$prefix = substr($line, 0, 1);
			if($prefix == '@')
				$class = " chunk_header";
			else if($prefix == '\\')
				$class = " incomplete";
			else if($prefix == '+')
				$class = " add";
			else if($prefix == '-')
				$class = " rem";
		}
		$lineobj->set('class', $class);
		$line = Tools::replaceTabs($line);
		$lineobj->set('line', htmlentities($line));
		
		return $lineobj;
	}
	
	private function gen_contentprovider($patch_id) {
		if(!$this->diff)
			$pageclass = 'patch_nodiff';
		else if(!$patch_id)
			$pageclass = 'patch_continued';
		else
			$pageclass = 'patch_normal';
		$page = new ContentProvider('commitdiff', $pageclass);
		$page->set('diffcmd', $this->gen_diffcmd_header());
		$page->set('patch_id', $patch_id);
		if(!$this->diff)
			return $page;
		$is_header = true;
		$first_header = true;
		for($i = 1; $i < count($this->diff); $i++) {
			$line = $this->diff[$i];
			if($is_header) {
				if(preg_match('/^--- |^diff /', $line))
					$is_header = false;
				else {
					if(!$first_header)
						$page->append('header', '<br />');
					$page->append('header', $this->gen_index_header($line));
					$first_header = false;
					continue;
				}
			}
			$page->append('patch', $this->format_line($line));
			
		}
		if($is_header)
			$page->set('patch', '');
		
		return $page;
	}
	
}

?>