<?php
require_once __DIR__ . '/lib/bootstrap.php';
$me = current_user();
$tid = (int)($_GET['t'] ?? 0);

$s = db()->prepare("SELECT t.*, f.name AS fname, f.is_locked AS flocked
                    FROM topics t JOIN forums f ON f.id=t.forum_id WHERE t.id=?");
$s->execute([$tid]);
$t = $s->fetch();
if (!$t) bail('Topic', 'No such topic.', '/forum.php');

$locked = $t['is_locked'] || $t['flocked'];

// reply / delete post
$err = '';
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $me = require_login();
    require_csrf();
    $act = $_POST['act'] ?? 'reply';
    if ($act === 'delpost' && $me['is_admin']) {
        db()->prepare("DELETE FROM posts WHERE id=? AND topic_id=?")
            ->execute([(int)($_POST['pid'] ?? 0), $tid]);
        redirect('/topic.php', ['t' => $tid]);
    }
    if ($locked && !$me['is_admin']) bail('Topic', 'Topic is locked.', '/forum.php');
    $body = trim((string)($_POST['body'] ?? ''));
    if ($body === '') {
        $err = 'Message cannot be empty.';
    } else {
        $now = time();
        db()->prepare("INSERT INTO posts (topic_id,user_id,body,created_at) VALUES (?,?,?,?)")
            ->execute([$tid, $me['id'], mb_substr($body, 0, 4000), $now]);
        db()->prepare("UPDATE topics SET bumped_at=? WHERE id=?")->execute([$now, $tid]);
        // jump to the last page
        $c = db()->prepare("SELECT COUNT(*) FROM posts WHERE topic_id=?");
        $c->execute([$tid]);
        $last = max(1, (int)ceil(((int)$c->fetchColumn()) / PER_PAGE));
        redirect('/topic.php', ['t' => $tid, 'p' => $last]);
    }
}

$page = max(1, (int)($_GET['p'] ?? 1));
$off  = ($page - 1) * PER_PAGE;
$s = db()->prepare("SELECT p.*, u.username FROM posts p
                    LEFT JOIN users u ON u.id=p.user_id
                    WHERE p.topic_id=? ORDER BY p.id LIMIT ? OFFSET ?");
$s->execute([$tid, PER_PAGE + 1, $off]);
$rows = $s->fetchAll();
$more = count($rows) > PER_PAGE;
if ($more) array_pop($rows);

page_start($t['title'], ['back' => '/forum.php?f=' . $t['forum_id']]);
if ($err) p_err($err);
p_para('In ' . $t['fname'] . ($locked ? ' [locked]' : ''));
p_rule();
foreach ($rows as $r) {
    p_para('-- ' . ($r['username'] ?? '[deleted]') . ', ' . ago((int)$r['created_at']) . ' ago:');
    p_para(wtrim($r['body']));
    if ($me && $me['is_admin']) {
        p_form('/topic.php?t=' . $tid, [
            ['name' => 'act', 'type' => 'hidden', 'value' => 'delpost'],
            ['name' => 'pid', 'type' => 'hidden', 'value' => (string)$r['id']],
        ], 'Del post');
    }
    p_rule();
}
p_pager('/topic.php', $page, $more, ['t' => $tid]);

if ($me && (!$locked || $me['is_admin'])) {
    p_para('Reply:');
    p_form('/topic.php?t=' . $tid, [
        ['name' => 'body', 'label' => 'Message', 'type' => is_wml() ? 'text' : 'textarea',
         'maxlength' => is_wml() ? 200 : 4000],
    ], 'Reply');
} elseif (!$me) {
    p_links([['/login.php', 'Log in to reply']]);
}
p_links([
    ['/forum.php', 'Back to ' . $t['fname'], ['f' => $t['forum_id']]],
    ['/forum.php', 'All forums'],
    ['/index.php', 'Home'],
]);
page_end();