feat(contest): add standings export

Resolves #124.

web/app/controllers/contest_inside.php

@@ -396,6 +396,14 @@ function echoStandings() {
 		$contest_data = queryContestData($contest);
 		calcStandings($contest, $contest_data, $score, $standings);
 
+		if ($contest['cur_progress'] >= CONTEST_FINISHED && hasContestPermission(Auth::user(), $contest)) {
+			echo <<<EOD
+				<div>
+					<a class="btn btn-info" href="/contest/{$contest['id']}/export_standings">下载排名</a>
+				</div>
+			EOD;
+		}
+
 		uojIncludeView('contest-standings', [
 			'contest' => $contest,
 			'standings' => $standings,
@@ -550,4 +558,4 @@ function echoContestFinished() {
 		<?php } ?>
 	</div>
 </div>
-<?php echoUOJPageFooter() ?>
+<?php echoUOJPageFooter() ?>

web/app/controllers/export_contest_standings_table.php

@@ -0,0 +1,68 @@
+<?php
+
+if (!validateUInt($_GET['id']) || !($contest = queryContest($_GET['id']))) {
+	become404Page();
+}
+genMoreContestInfo($contest);
+
+if (!hasContestPermission(Auth::user(), $contest)) {
+	becomeMsgPage('您没有权限下载此比赛的排名。');
+}
+if ($contest['cur_progress'] < CONTEST_FINISHED) {
+	becomeMsgPage('比赛尚未结束，无法下载排名。');
+}
+
+$contest_data = queryContestData($contest);
+calcStandings($contest, $contest_data, $score, $standings);
+
+function array2csv(array &$array) {
+	if (count($array) == 0) {
+		return null;
+	}
+
+	ob_start();
+
+	$df = fopen("php://output", 'w');
+
+	fputcsv($df, array_keys(reset($array)));
+
+	foreach ($array as $row) {
+		fputcsv($df, $row);
+	}
+
+	fclose($df);
+
+	return ob_get_clean();
+}
+
+$export_data = [];
+$csv_header = ['Rank', 'Username', 'Score', 'Penalty'];
+$n_problems = count($contest_data['problems']);
+
+for ($i = 0; $i < $n_problems; $i++) {
+	$csv_header[] = chr(ord('A') + $i);
+	$csv_header[] = chr(ord('A') + $i) . '_penalty';
+	$csv_header[] = chr(ord('A') + $i) . '_submission_id';
+}
+
+$export_data[] = $csv_header;
+
+// Convert data in $standings and $score to $export_data
+foreach ($standings as $rank => $row) {
+	$row = [$rank, $row[2][0], $row[0], $row[1]];
+	for ($i = 0; $i < $n_problems; $i++) {
+		$row[] = $score[$row[2][0]][$i][0] ?: "";
+		$row[] = $score[$row[2][0]][$i][1] ?: "";
+		$row[] = $score[$row[2][0]][$i][2] ?: "";
+	}
+	$export_data[] = $row;
+}
+
+$csv = array2csv($export_data);
+
+header("Cache-Control: max-age=0, no-cache, must-revalidate, proxy-revalidate");
+header("Last-Modified: {$now} GMT");
+header("Content-Type: text/csv");
+header("Content-Disposition: attachment;filename={$contest['id']}_standings.csv");
+
+die($csv);

web/app/route.php

@@ -28,6 +28,7 @@
 		Route::any('/contest/{id}/submissions', '/contest_inside.php?tab=submissions');
 		Route::any('/contest/{id}/standings', '/contest_inside.php?tab=standings');
 		Route::any('/contest/{id}/backstage', '/contest_inside.php?tab=backstage');
+		Route::any('/contest/{id}/export_standings', '/export_contest_standings_table.php');
 		Route::any('/contest/{contest_id}/problem/{id}', '/problem.php');
 		Route::any('/contest/{contest_id}/problem/{id}/statistics', '/problem_statistics.php');