<?php
/*************************************************************
# 076 License

Copyright (c) テクニカル諏訪子

Permission is hereby granted to any person obtaining a copy of the software
Little Beast (the "Software") to use, modify, merge, copy, publish, distribute,
sublicense, and/or sell copies of the Software, subject to the following conditions:

    1. **Origin Attribution**:
       - You must not misrepresent the origin of the Software; you must not claim
         you created the original Software.
       - If the Software is used in a product, you must either:
         a. Provide clear attribution in the product's documentation, user interface,
            or other visible areas, **OR**
         b. Pay the original developers a fee they specify in writing.
    2. **Usage Restriction**:
       - The Software, or any derivative works, dependencies, or libraries
         incorporating it, must not be used for censorship or to suppress freedom of
         speech, expression, or creativity. Prohibited uses include, but are not
         limited to:
         - Censorship of so-called "hate speech", visuals, non-mainstream opinions,
           ideas, or objective reality.
         - Tools or systems designed to restrict access to information or
           artistic works.
    3. **Notice Preservation**:
       - This license and the above copyright notice must remain intact in all copies
         of the source code.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
namespace Site\Controller;

use Std\Lib\Activitypub;
use Std\Lib\Fedi\Remote;
use Std\Lib\Gitler\Federation;
use Std\Lib\Gitler\Gitler as Hosting;
use Std\Lib\Gitler\Issues;
use Std\Lib\Gitler\Notify;

/**
 * Gitlerのイシュー、ラベル、マイルストーンのページ、ウォッチ、リポジトリのFediverse（アクター、受付ボックス等）
 *
 * Gitlerコントローラーで使う（リポジトリを開く等はGitlerの物）。
 */
trait GitlerIssues {
  private ?Issues $issueDb = null;
  /** 表示したユーザーのアバター */
  private array $avatars = [];

  //////// イシュー

  /** …/issues?state=&label=&milestone=&assignee=&q=&sort=&page=（…/pullsはプルリクエスト） */
  public function issues(array $params): void {
    $pull = !empty($params['pull']);
    $this->loadIssues($params, $pull);
    $f = ['state' => in_array($_GET['state'] ?? '', ['closed', 'all'], true) ? $_GET['state'] : 'open'];
    foreach (['label', 'milestone'] as $k) if (isset($_GET[$k]) && $_GET[$k] !== '') $f[$k] = (int)$_GET[$k];
    foreach (['assignee', 'q', 'sort'] as $k) if (is_string($_GET[$k] ?? null) && $_GET[$k] !== '') $f[$k] = trim($_GET[$k]);
    $all = $this->issueDb->search(['state' => 'all', 'pull' => $pull] + $f);
    $counts = ['open' => 0, 'closed' => 0];
    foreach ($all as $s) $counts[$s['state']]++;
    $list = $f['state'] === 'all' ? $all : array_values(array_filter($all, fn($s) => $s['state'] === $f['state']));
    $page = max(1, (int)($_GET['page'] ?? 1));
    $pages = max(1, (int)ceil(count($list) / self::PER_PAGE));
    $labels = $this->issueDb->labels();
    $milestones = $this->issueDb->milestones();
    $listUrl = $this->repoUrl().($pull ? '/pulls' : '/issues');
    $query = fn(array $change) => $listUrl.'?'.http_build_query(array_filter($change + $f + ['page' => null], fn($v) => $v !== null && $v !== ''));
    $this->renderRepo('gitler/issues', $pull ? 'プルリクエスト' : 'イシュー', [
      'isPull' => $pull, 'listUrl' => $listUrl, 'newUrl' => $this->repoUrl().($pull ? '/compare' : '/issues/new'),
      'agitHelp' => $pull ? 'git push origin HEAD:refs/for/'.$this->defaultBranch().'/トピック' : '',
      'list' => array_map(fn($s) => $this->presentSummary($s, $labels, $milestones), array_slice($list, ($page - 1) * self::PER_PAGE, self::PER_PAGE)),
      'counts' => $counts, 'f' => $f + ['label' => '', 'milestone' => '', 'assignee' => '', 'q' => '', 'sort' => 'created'],
      'openUrl' => $query(['state' => 'open']), 'closedUrl' => $query(['state' => 'closed']),
      'prevUrl' => $page > 1 ? $query(['page' => $page - 1]) : '', 'nextUrl' => $page < $pages ? $query(['page' => $page + 1]) : '',
      'labels' => $this->presentLabels($labels), 'milestones' => $milestones, 'people' => $this->assignable(), 'canIssue' => $pull ? $this->canPull() : $this->canIssue(),
    ]);
  }

  /** …/issues/new */
  public function newIssue(array $params): void {
    $this->loadIssues($params);
    if (!$this->user) $this->redirect('/login');
    if ($this->meta['archived']) $this->message('アーカイブされたリポジトリです（読むだけ）。', $this->repoUrl().'/issues');
    if (!$this->canIssue()) $this->message('イシューを作る権限が有りません。', $this->repoUrl().'/issues');
    $in = ['title' => '', 'body' => '', 'labels' => [], 'assignees' => [], 'milestone' => 0];
    $error = '';
    if ($_SERVER['REQUEST_METHOD'] === 'POST') {
      $in = ['title' => (string)($_POST['title'] ?? ''), 'body' => str_replace("\r\n", "\n", (string)($_POST['body'] ?? '')),
             'labels' => (array)($_POST['labels'] ?? []), 'assignees' => (array)($_POST['assignees'] ?? []), 'milestone' => (int)($_POST['milestone'] ?? 0)];
      if (!$this->csrfOk()) {
        $error = 'セッションの有効期限が切れました。もう一度お試し下さい。';
      } else {
        $opt = $this->access >= Hosting::WRITE ? ['labels' => $in['labels'], 'assignees' => array_intersect($in['assignees'], $this->assignable()), 'milestone' => $in['milestone']] : [];
        $res = $this->issueDb->create($this->me(), $in['title'], $in['body'], $opt);
        if ($res->isSuccess) {
          Federation::issueOpened($this->owner, $this->name, $this->meta, $res->data['issue']);
          Notify::issueOpened($this->owner, $this->name, $this->meta, $this->issueDb, $res->data['issue']);
          $this->redirect($this->repoUrl().'/issues/'.$res->data['number']);
        }
        $error = (string)$res->message;
      }
    }
    $this->renderRepo('gitler/issuenew', '新しいイシュー', [
      'in' => $in, 'error' => $error, 'labels' => $this->presentLabels($this->issueDb->labels(), array_map('intval', $in['labels'])),
      'milestones' => $this->issueDb->milestones(), 'people' => $this->assignable(),
    ]);
  }

  /** …/issues/{n}（ActivityPubではNote）、…/pulls/{n}（プルリクエストの会話） */
  public function issue(array $params): void {
    $n = (int)($params['n'] ?? 0);
    if ($this->wantsActivity()) {
      [$owner, $name, $issue] = $this->apIssue($params);
      $this->apJson(['@context' => Federation::CONTEXT] + Federation::issueNote($owner, $name, $issue));
    }
    $this->loadIssues($params, null);
    $issue = $this->issueDb->get($n);
    if ($issue === null) $this->notFound();
    // イシューとプルリクエストのURLが違う
    if (isset($issue['pull']) !== !empty($params['pull'])) $this->redirect($this->issuePage($issue));
    if (!(isset($issue['pull']) ? $this->meta['pulls'] : $this->meta['issues'])) $this->notFound();
    $error = '';
    if ($_SERVER['REQUEST_METHOD'] === 'POST') {
      $error = $this->csrfOk() ? $this->issueAction($issue) : 'セッションの有効期限が切れました。もう一度お試し下さい。';
      $issue = $this->issueDb->get($n);
      if ($issue === null) $this->redirect($this->repoUrl().'/issues');
    }
    $pull = isset($issue['pull']);
    header('Vary: Accept');
    $isAuthor = $this->user && ($issue['author']['user'] ?? null) === $this->user->username;
    $archived = $this->meta['archived'];
    $labels = $this->issueDb->labels();
    $milestones = $this->issueDb->milestones();
    $timeline = [];
    $replies = [];
    foreach ($issue['comments'] as $c) if (isset($c['path']) && $c['replyTo'] !== null && empty($c['pending'])) $replies[$c['replyTo']][] = $c;
    $byReview = [];
    foreach ($issue['comments'] as $c) {
      // 行へのコメント：レビューの物はレビューに、他はそれだけ（返信はスレッドに、下書きは出さない）
      if (isset($c['path'])) {
        if (!empty($c['pending']) || $c['replyTo'] !== null) continue;
        $inline = $this->presentInline($c, $replies[$c['id']] ?? []) + ['outdated' => $c['commit'] !== $issue['pull']['headId']];
        if ($c['review'] !== null) $byReview[$c['review']][] = $inline;
        else $timeline[] = ['kind' => 'inline', 'at' => $c['created'], 'c' => $inline];
        continue;
      }
      $mine = $this->user && ($c['author']['user'] ?? null) === $this->user->username;
      $timeline[] = ['kind' => 'comment', 'at' => $c['created'], 'id' => $c['id'], 'who' => $this->who($c['author']), 'html' => $this->bodyHtml($c['body'], !empty($c['html'])),
                     'date' => date('Y-m-d H:i', $c['created']), 'edited' => $c['updated'] > $c['created'], 'body' => $c['body'], 'canEdit' => !$archived && $mine && empty($c['html']),
                     'canDelete' => !$archived && ($mine || $this->access >= Hosting::ADMIN), 'actor' => $c['author']['actor'] ?? '',
                     'remote' => preg_match('#^https?://#i', (string)($c['remoteId'] ?? '')) ? $c['remoteId'] : ''];
    }
    foreach ($issue['events'] as $e) $timeline[] = ['kind' => 'event', 'at' => $e['at'], 'html' => $this->eventHtml($e, $labels, $milestones), 'date' => date('Y-m-d H:i', $e['at'])];
    $states = ['approved' => '承認しました', 'changes' => '変更を依頼しました', 'commented' => 'レビューしました'];
    foreach ($issue['reviews'] ?? [] as $r) {
      $timeline[] = ['kind' => 'review', 'at' => $r['at'], 'id' => $r['id'], 'who' => $this->who($r['author']), 'state' => $r['state'], 'stateText' => $states[$r['state']] ?? '',
                     'html' => trim($r['body']) !== '' ? $this->bodyHtml($r['body'], false) : '', 'date' => date('Y-m-d H:i', $r['at']), 'comments' => $byReview[$r['id']] ?? []];
    }
    // 同じ時刻なら出来事（閉じた、マージした等）を後に
    usort($timeline, fn($a, $b) => [$a['at'], $a['kind'] === 'event'] <=> [$b['at'], $b['kind'] === 'event']);
    $fedi = Federation::enabled($this->meta) && !$this->meta['archived'];
    // 通知：受け取っている（true）、止めた（false）、ウォッチで受け取る、受け取っていない
    $sub = $this->user ? ($issue['subscribers'][$this->user->username] ?? null) : null;
    $watching = $this->user && Notify::watchState($this->owner, $this->name, (string)$this->user->username, $this->meta) === Notify::WATCHING;
    $this->renderRepo($pull ? 'gitler/pull' : 'gitler/issue', '#'.$n.' '.$issue['title'], ($pull ? $this->pullVars($issue) : []) + [
      'issue' => $issue, 'who' => $this->who($issue['author']), 'bodyHtml' => $this->bodyHtml($issue['body'], !empty($issue['html'])),
      'date' => date('Y-m-d H:i', $issue['created']), 'timeline' => $timeline, 'error' => $error,
      'canIssue' => $pull ? $this->canReview() : $this->canIssue(), 'canEdit' => !$archived && (($isAuthor && empty($issue['html'])) || $this->access >= Hosting::WRITE),
      'canClose' => !$archived && ($isAuthor || $this->access >= Hosting::WRITE) && empty($issue['pull']['merged']), 'canTriage' => !$archived && $this->access >= Hosting::WRITE,
      'canAdmin' => !$archived && $this->access >= Hosting::ADMIN,
      'labels' => $this->presentLabels($labels, $issue['labels']), 'issueLabels' => $this->presentLabels(array_intersect_key($labels, array_flip($issue['labels']))),
      'milestones' => $milestones, 'milestone' => $issue['milestone'] !== null ? ($milestones[$issue['milestone']]['title'] ?? '') : '',
      'people' => array_map(fn($p) => ['name' => $p, 'checked' => in_array($p, $issue['assignees'], true)], array_unique(array_merge($this->assignable(), $issue['assignees']))),
      'issueUrl' => $this->issuePage($issue), 'fedi' => $fedi, 'canReview' => $pull && $this->canReview(),
      'fediHandle' => $fedi ? '@'.Federation::handle($this->owner, $this->name).'@'.\Std\Lib\Fedi\Fedi::host() : '',
      'fediUrl' => $fedi ? Federation::issueUrl($this->owner, $this->name, $n) : '',
      'subscribed' => $sub === true || ($sub === null && $watching),
      'subscribeNote' => $sub === true ? '通知を受け取っています。' : ($sub === false ? '通知を止めています。' : ($watching ? 'リポジトリをウォッチしているので通知を受け取ります。' : '通知を受け取っていません。')),
    ]);
  }

  /** …/issues/{n}/ticket（ForgeFedのTicket。ブラウザはイシューへ） */
  public function issueTicket(array $params): void {
    if (!$this->wantsActivity()) $this->redirect('/gitler/'.($params['owner'] ?? '').'/'.rawurlencode((string)($params['repo'] ?? '')).'/issues/'.(int)($params['n'] ?? 0));
    [$owner, $name, $issue] = $this->apIssue($params);
    $this->apJson(Federation::ticket($owner, $name, $issue));
  }

  /** …/issues/{n}/comments/{c}（ローカルのコメントのNote。ブラウザはコメントへ） */
  public function issueComment(array $params): void {
    $c = (int)($params['c'] ?? 0);
    if (!$this->wantsActivity()) $this->redirect('/gitler/'.($params['owner'] ?? '').'/'.rawurlencode((string)($params['repo'] ?? '')).'/issues/'.(int)($params['n'] ?? 0).'#c'.$c);
    [$owner, $name, $issue] = $this->apIssue($params);
    foreach ($issue['comments'] as $x) {
      if ($x['id'] === $c && !isset($x['author']['actor'])) $this->apJson(['@context' => Federation::CONTEXT] + Federation::commentNote($owner, $name, $issue, $x));
    }
    $this->apJson(['error' => '見つかりません'], 404);
  }

  /** イシューのページのPOST（エラーのメッセージ、成功したらリダイレクト） */
  private function issueAction(array $issue): string {
    $n = $issue['number'];
    $url = $this->issuePage($issue);
    $do = (string)($_POST['do'] ?? '');
    if (isset($issue['pull']) && in_array($do, ['merge', 'deleteBranch', 'inline', 'inlinePending', 'reply', 'review'], true)) return $this->pullAction($issue, $do);
    $me = $this->me();
    $isAuthor = $this->user && ($issue['author']['user'] ?? null) === $this->user->username;
    $canClose = $isAuthor || $this->access >= Hosting::WRITE;
    $body = str_replace("\r\n", "\n", (string)($_POST['body'] ?? ''));
    if (!$this->user) return 'ログインして下さい。';

    if ($do === 'subscribe' || $do === 'unsubscribe') {
      $this->issueDb->subscribe($n, [(string)$this->user->username], $do === 'subscribe');
      $this->redirect($url);
    }
    if ($this->meta['archived']) return 'アーカイブされたリポジトリです（読むだけ）。';

    if (in_array($do, ['comment', 'commentClose', 'commentReopen', 'close', 'reopen'], true)) {
      if (!(isset($issue['pull']) ? $this->canReview() : $this->canIssue())) return 'コメントする権限が有りません。';
      if (!empty($issue['pull']['merged']) && $do !== 'comment') return 'マージしたプルリクエストは開き直せません。';
      $anchor = '';
      if ($do === 'comment' || trim($body) !== '') {
        $res = $this->issueDb->comment($n, $me, $body);
        if (!$res->isSuccess) return (string)$res->message;
        Federation::commentAdded($this->owner, $this->name, $this->meta, $res->data['issue'], $res->data['comment']);
        Notify::commented($this->owner, $this->name, $this->meta, $this->issueDb, $res->data['issue'], $res->data['comment']);
        $anchor = '#c'.$res->data['comment']['id'];
      }
      if ($do !== 'comment' && $canClose) {
        $new = $this->issueDb->setState($n, in_array($do, ['reopen', 'commentReopen'], true), $me);
        if ($new !== null) {
          Federation::stateChanged($this->owner, $this->name, $this->meta, $new);
          Notify::stateChanged($this->owner, $this->name, $this->meta, $new, $me);
        }
      }
      $this->redirect($url.$anchor);
    }
    if ($do === 'edit') {
      if (!(($isAuthor && empty($issue['html'])) || $this->access >= Hosting::WRITE)) return '編集する権限が有りません。';
      $res = $this->issueDb->edit($n, $me, (string)($_POST['title'] ?? ''), empty($issue['html']) ? $body : $issue['body']);
      if (!$res->isSuccess) return (string)$res->message;
      Federation::issueEdited($this->owner, $this->name, $this->meta, $res->data['issue']);
      $this->redirect($url);
    }
    if ($do === 'triage') {
      if ($this->access < Hosting::WRITE) return '権限が有りません。';
      $people = array_merge($this->assignable(), $issue['assignees']);
      $new = $this->issueDb->triage($n, $me, (array)($_POST['labels'] ?? []), array_values(array_intersect((array)($_POST['assignees'] ?? []), $people)), (int)($_POST['milestone'] ?? 0));
      $added = $new !== null ? array_values(array_diff($new['assignees'], $issue['assignees'])) : [];
      if (!empty($added)) Notify::assigned($this->owner, $this->name, $this->meta, $new, $added, $me);
      $this->redirect($url);
    }
    if ($do === 'editComment' || $do === 'deleteComment') {
      $id = (int)($_POST['id'] ?? 0);
      $c = null;
      foreach ($issue['comments'] as $x) if ($x['id'] === $id) $c = $x;
      if ($c === null) return 'コメントが有りません。';
      $mine = ($c['author']['user'] ?? null) === $this->user->username;
      if ($do === 'editComment') {
        if (!$mine || !empty($c['html'])) return '編集する権限が有りません。';
        $new = $this->issueDb->editComment($n, $id, $body);
        if ($new === null) return 'コメントを入力して下さい。';
        Federation::commentAdded($this->owner, $this->name, $this->meta, $this->issueDb->get($n) ?? $issue, $new, 'Update');
        $this->redirect($url.'#c'.$id);
      }
      if (!$mine && $this->access < Hosting::ADMIN) return '削除する権限が有りません。';
      $this->issueDb->editComment($n, $id, null);
      Federation::commentDeleted($this->owner, $this->name, $this->meta, $issue, $c);
      $this->redirect($url);
    }
    if ($do === 'delete') {
      if ($this->access < Hosting::ADMIN) return '削除する権限が有りません。';
      if (!isset($_POST['confirm'])) return '確認にチェックを入れて下さい。';
      $this->issueDb->delete($n);
      Federation::issueDeleted($this->owner, $this->name, $this->meta, $issue);
      if (isset($issue['pull'])) {
        try {
          $this->repo->refs->update(\Std\Lib\Gitler\Pulls::ref($n), null);
        } catch (\Std\Lib\Git\GitException) {
        }
      }
      $this->redirect($this->repoUrl().(isset($issue['pull']) ? '/pulls' : '/issues'));
    }
    if ($do === 'block') {
      if ($this->access < Hosting::ADMIN) return 'ブロックする権限が有りません。';
      $res = Federation::block($this->owner, $this->name, (string)($_POST['actor'] ?? ''));
      return $res->isSuccess ? '' : (string)$res->message;
    }
    return '';
  }

  //////// ウォッチ

  /** …/watch（POST：state＝watching、participating、ignoring） */
  public function watch(array $params): void {
    $this->load($params);
    if (!$this->user) $this->redirect('/login');
    if ($_SERVER['REQUEST_METHOD'] === 'POST' && $this->csrfOk()) Notify::setWatch($this->owner, $this->name, (string)$this->user->username, (string)($_POST['state'] ?? ''));
    $back = (string)($_POST['back'] ?? '');
    $this->redirect(str_starts_with($back, $this->repoUrl()) ? $back : $this->repoUrl());
  }

  //////// ラベルとマイルストーン

  /** …/labels */
  public function labels(array $params): void {
    $this->loadIssues($params, null);
    $error = '';
    if ($_SERVER['REQUEST_METHOD'] === 'POST') {
      if (!$this->csrfOk()) {
        $error = 'セッションの有効期限が切れました。もう一度お試し下さい。';
      } else if ($this->access < Hosting::WRITE || $this->meta['archived']) {
        $error = $this->meta['archived'] ? 'アーカイブされたリポジトリです（読むだけ）。' : '権限が有りません。';
      } else if (($_POST['do'] ?? '') === 'delete') {
        $this->issueDb->deleteLabel((int)($_POST['id'] ?? 0));
        $this->redirect($this->repoUrl().'/labels');
      } else {
        $id = (int)($_POST['id'] ?? 0);
        $res = $this->issueDb->saveLabel($id > 0 ? $id : null, (string)($_POST['name'] ?? ''), (string)($_POST['color'] ?? ''), (string)($_POST['description'] ?? ''));
        if ($res->isSuccess) $this->redirect($this->repoUrl().'/labels');
        $error = (string)$res->message;
      }
    }
    $counts = [];
    foreach ($this->issueDb->search(['state' => 'open']) as $s) foreach ($s['labels'] as $l) $counts[$l] = ($counts[$l] ?? 0) + 1;
    $list = [];
    foreach ($this->presentLabels($this->issueDb->labels()) as $l) $list[] = $l + ['open' => $counts[$l['id']] ?? 0, 'url' => $this->repoUrl().'/issues?label='.$l['id']];
    $this->renderRepo('gitler/labels', 'ラベル', ['list' => $list, 'error' => $error, 'canTriage' => $this->access >= Hosting::WRITE && !$this->meta['archived']]);
  }

  /** …/milestones */
  public function milestones(array $params): void {
    $this->loadIssues($params, null);
    $error = '';
    if ($_SERVER['REQUEST_METHOD'] === 'POST') {
      $do = (string)($_POST['do'] ?? '');
      $id = (int)($_POST['id'] ?? 0);
      $all = $this->issueDb->milestones();
      if (!$this->csrfOk()) {
        $error = 'セッションの有効期限が切れました。もう一度お試し下さい。';
      } else if ($this->access < Hosting::WRITE || $this->meta['archived']) {
        $error = $this->meta['archived'] ? 'アーカイブされたリポジトリです（読むだけ）。' : '権限が有りません。';
      } else if ($do === 'delete') {
        $this->issueDb->deleteMilestone($id);
        $this->redirect($this->repoUrl().'/milestones');
      } else if (($do === 'close' || $do === 'reopen') && isset($all[$id])) {
        $m = $all[$id];
        $this->issueDb->saveMilestone($id, $m['title'], $m['description'], $m['due'], $do === 'close' ? 'closed' : 'open');
        $this->redirect($this->repoUrl().'/milestones'.($do === 'close' ? '?state=closed' : ''));
      } else {
        $old = $all[$id] ?? null;
        $res = $this->issueDb->saveMilestone($old ? $id : null, (string)($_POST['title'] ?? ''), (string)($_POST['description'] ?? ''), trim((string)($_POST['due'] ?? '')), $old['state'] ?? 'open');
        if ($res->isSuccess) $this->redirect($this->repoUrl().'/milestones');
        $error = (string)$res->message;
      }
    }
    $state = ($_GET['state'] ?? '') === 'closed' ? 'closed' : 'open';
    $stats = [];
    foreach ($this->issueDb->search(['state' => 'all']) as $s) if ($s['milestone'] !== null) $stats[$s['milestone']][$s['state']] = ($stats[$s['milestone']][$s['state']] ?? 0) + 1;
    $list = [];
    $counts = ['open' => 0, 'closed' => 0];
    foreach ($this->issueDb->milestones() as $id => $m) {
      $counts[$m['state']]++;
      if ($m['state'] !== $state) continue;
      $open = $stats[$id]['open'] ?? 0;
      $closed = $stats[$id]['closed'] ?? 0;
      $list[] = $m + ['id' => $id, 'open' => $open, 'closed' => $closed, 'percent' => $open + $closed > 0 ? (int)floor($closed * 100 / ($open + $closed)) : 0,
                      'overdue' => $m['due'] !== '' && $m['state'] === 'open' && $m['due'] < date('Y-m-d'),
                      'html' => $m['description'] !== '' ? Issues::render($m['description'], $this->repoUrl().'/issues') : '',
                      'url' => $this->repoUrl().'/issues?state=all&milestone='.$id];
    }
    usort($list, fn($a, $b) => [$a['due'] === '' ? '9999' : $a['due'], $a['id']] <=> [$b['due'] === '' ? '9999' : $b['due'], $b['id']]);
    $this->renderRepo('gitler/milestones', 'マイルストーン', ['list' => $list, 'error' => $error, 'state' => $state, 'counts' => $counts,
                                                         'canTriage' => $this->access >= Hosting::WRITE && !$this->meta['archived']]);
  }

  //////// ActivityPub（リポジトリのアクター）

  /** アクターのJSON（…/gitler/{owner}/{repo}をActivityPubで取得） */
  private function apActor(array $params): never {
    [$owner, $name, $meta] = $this->apRepo($params);
    $this->owner = $owner;
    $this->name = $name;
    $this->apJson(Federation::document($owner, $name, $meta, $this->cloneUrls()['https']));
  }

  /** …/inbox */
  public function inbox(array $params): void {
    if ($_SERVER['REQUEST_METHOD'] !== 'POST') $this->apJson(['error' => 'POSTだけです'], 405);
    [$owner, $name] = $this->apRepo($params);
    $max = 262144;
    $input = file_get_contents('php://input', false, null, 0, $max + 1);
    if ($input === false || strlen($input) > $max) $this->apJson(['error' => '大き過ぎます'], 413);
    $activity = json_decode($input, true);
    if (!is_array($activity) || !is_string($activity['type'] ?? null)) $this->apJson(['error' => '不正なアクティビティ'], 400);
    if (!(new Activitypub())->verifyInboxSignature($input, $activity)) {
      // 削除されたアカウントは鍵を取得出来ないので、Deleteは受け流す
      $this->apJson($activity['type'] === 'Delete' ? ['status' => '無視しました'] : ['error' => '署名の検証に失敗'], $activity['type'] === 'Delete' ? 202 : 401);
    }
    logger(\LogType::ActivityPub, "Gitler（{$owner}/{$name}）の受付に入れた：".$input);
    [$code, $body] = Federation::receive($owner, $name, $activity);
    $this->apJson($body, $code);
  }

  /** …/outbox（最近のイシュー20件） */
  public function outbox(array $params): void {
    [$owner, $name] = $this->apRepo($params);
    $issues = Issues::open($owner, $name);
    $items = [];
    foreach (array_slice($issues->search(['state' => 'all']), 0, 20) as $s) {
      $issue = $issues->get($s['number']);
      if ($issue === null) continue;
      $note = Federation::issueNote($owner, $name, $issue);
      $items[] = ['id' => $note['id'].'#create', 'type' => 'Create', 'actor' => $note['attributedTo'], 'published' => $note['published'], 'to' => $note['to'], 'cc' => $note['cc'], 'object' => $note];
    }
    $url = Federation::actorUrl($owner, $name).'/outbox';
    $this->apJson(['@context' => Federation::CONTEXT, 'id' => $url, 'type' => 'OrderedCollection', 'totalItems' => count($issues->index()['issues']), 'orderedItems' => $items]);
  }

  /** …/followers（数だけ） */
  public function followers(array $params): void {
    [$owner, $name] = $this->apRepo($params);
    $this->apJson(['@context' => 'https://www.w3.org/ns/activitystreams', 'id' => Federation::actorUrl($owner, $name).'/followers', 'type' => 'OrderedCollection',
                   'totalItems' => count(Federation::followers($owner, $name))]);
  }

  /** Fediverseに出ているリポジトリ（[所有者, 名前, meta]、無ければ404） */
  private function apRepo(array $params): array {
    $owner = (string)($params['owner'] ?? '');
    $name = (string)($params['repo'] ?? '');
    if (!Hosting::validOwner($owner) || !Hosting::validName($name) || !Hosting::exists($owner, $name)) $this->apJson(['error' => '見つかりません'], 404);
    $meta = Hosting::meta($owner, $name);
    if (!Federation::enabled($meta)) $this->apJson(['error' => '見つかりません'], 404);
    return [$owner, $name, $meta];
  }

  /** ActivityPubで取得するイシュー（[所有者, 名前, イシュー]） */
  private function apIssue(array $params): array {
    [$owner, $name] = $this->apRepo($params);
    $issue = Issues::open($owner, $name)->get((int)($params['n'] ?? 0));
    if ($issue === null) $this->apJson(['error' => '見つかりません'], 404);
    return [$owner, $name, $issue];
  }

  private function wantsActivity(): bool {
    $accept = strtolower((string)($_SERVER['HTTP_ACCEPT'] ?? ''));
    return str_contains($accept, 'application/activity+json') || str_contains($accept, 'application/ld+json');
  }

  private function apJson(array $data, int $code = 200): never {
    http_response_code($code);
    header('Content-Type: application/activity+json; charset=utf-8');
    header('Vary: Accept');
    echo json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
    exit;
  }

  //////// プッシュ

  /** プッシュの後：コミットのメッセージの「fixes #3」等でイシューを閉じる */
  public static function afterPush(string $owner, string $name, array $done): void {
    try {
      $meta = Hosting::meta($owner, $name);
      if (!$meta['issues']) return;
      $issues = Issues::open($owner, $name);
      $head = $issues->repo->headRef() ?? 'refs/heads/'.Hosting::config()['branch'];
      foreach ($issues->processPush($done, $head) as $n) {
        $issue = $issues->get($n);
        if ($issue === null) continue;
        Federation::stateChanged($owner, $name, $meta, $issue);
        Notify::stateChanged($owner, $name, $meta, $issue, end($issue['events'])['by'] ?? []);
      }
    } catch (\Throwable $e) {
      // プッシュ自体は終わっている
      @error_log('Gitler: '.$e->getMessage());
    }
  }

  //////// 共通

  /** @param bool|null $pull  プルリクエスト（nullならイシューかプルリクエストのどちらかが使えれば良い） */
  private function loadIssues(array $params, ?bool $pull = false): void {
    $this->load($params);
    $on = $pull === null ? $this->meta['issues'] || $this->meta['pulls'] : ($pull ? $this->meta['pulls'] : $this->meta['issues']);
    if (!$on) $this->notFound();
    $this->issueDb = new Issues($this->repo);
  }

  /** イシュー又はプルリクエストのページ */
  private function issuePage(array $issue): string {
    return $this->repoUrl().(isset($issue['pull']) ? '/pulls/' : '/issues/').$issue['number'];
  }

  /** イシューを作ってコメント出来るか */
  private function canIssue(): bool {
    return $this->user !== null && $this->meta['issues'] && !$this->meta['archived'] && Hosting::userCan($this->user, 'issues');
  }

  private function me(): array {
    return ['user' => (string)$this->user->username];
  }

  /** 担当者に出来る人（所有者と共同作業者） */
  private function assignable(): array {
    return array_values(array_unique(array_merge([$this->owner], array_map('strval', array_keys($this->meta['collaborators'])))));
  }

  /** 書いた者の表示（name、url、icon、remote） */
  private function who(array $a): array {
    if (isset($a['user'])) {
      $u = (string)$a['user'];
      if (!array_key_exists($u, $this->avatars)) {
        $x = Hosting::user($u);
        $this->avatars[$u] = $x ? avatar_url($x) : '';
      }
      return ['name' => $u, 'url' => '/gitler/'.$u, 'icon' => $this->avatars[$u], 'remote' => false, 'handle' => ''];
    }
    if (isset($a['actor'])) {
      return ['name' => Federation::authorName($a), 'url' => (string)($a['url'] ?? $a['actor']), 'icon' => Remote::imageUrl((string)($a['icon'] ?? '')), 'remote' => true,
              'handle' => (string)($a['handle'] ?? '')];
    }
    return ['name' => (string)($a['name'] ?? ''), 'url' => isset($a['commit']) ? $this->repoUrl().'/commit/'.$a['commit'] : '', 'icon' => '', 'remote' => false, 'handle' => ''];
  }

  private function bodyHtml(string $body, bool $html): string {
    if ($html) return $body;
    return trim($body) === '' ? '<p class="gl-muted">（説明は有りません）</p>' : Issues::render($body, $this->repoUrl().'/issues');
  }

  /** ラベルの表示（id、name、color、fg（文字の色）、description、checked） */
  private function presentLabels(array $labels, array $checked = []): array {
    $out = [];
    foreach ($labels as $id => $l) {
      $rgb = sscanf($l['color'], '#%02x%02x%02x');
      $out[] = $l + ['id' => $id, 'fg' => (0.299 * $rgb[0] + 0.587 * $rgb[1] + 0.114 * $rgb[2]) > 150 ? '#000000' : '#ffffff', 'checked' => in_array($id, $checked, true)];
    }
    usort($out, fn($a, $b) => strcasecmp($a['name'], $b['name']));
    return $out;
  }

  private function presentSummary(array $s, array $labels, array $milestones): array {
    $who = $this->who($s['author']);
    return ['number' => $s['number'], 'title' => $s['title'], 'url' => $this->repoUrl().(empty($s['pull']) ? '/issues/' : '/pulls/').$s['number'],
            'state' => !empty($s['merged']) ? 'merged' : $s['state'],
            'labels' => $this->presentLabels(array_intersect_key($labels, array_flip($s['labels']))), 'author' => $who['name'],
            'date' => date('Y-m-d', $s['created']), 'closedDate' => $s['closed'] ? date('Y-m-d', $s['closed']) : '', 'comments' => $s['comments'],
            'milestone' => $s['milestone'] !== null ? ($milestones[$s['milestone']]['title'] ?? '') : '', 'assignees' => $s['assignees']];
  }

  /** 出来事の文（HTML） */
  private function eventHtml(array $e, array $labels, array $milestones): string {
    $h = fn(string $s) => htmlspecialchars($s, ENT_QUOTES, 'UTF-8');
    $who = $this->who($e['by']);
    $by = $who['url'] !== '' ? '<a href="'.$h($who['url']).'">'.$h($who['name']).'</a>' : '<b>'.$h($who['name']).'</b>';
    $commit = fn(string $id) => '<a href="'.$h($this->repoUrl().'/commit/'.$id).'"><code>'.$h(substr($id, 0, 7)).'</code></a>';
    $chip = function(int $id) use ($labels, $h): string {
      $l = $this->presentLabels(isset($labels[$id]) ? [$id => $labels[$id]] : [])[0] ?? null;
      return $l ? '<span class="gl-label" style="background-color: '.$h($l['color']).'; color: '.$l['fg'].';">'.$h($l['name']).'</span>' : '<s>?</s>';
    };
    $list = fn(array $xs, callable $f) => implode('、', array_map($f, $xs));
    return match ($e['type']) {
      'closed' => isset($e['commit']) ? 'コミット'.$commit($e['commit']).'（'.$by.'）で閉じました'
                  : (isset($e['pull']) ? $by.'がプルリクエスト<a href="'.$h($this->repoUrl().'/pulls/'.$e['pull']).'">#'.(int)$e['pull'].'</a>のマージで閉じました' : $by.'が閉じました'),
      'pushed' => $by.'がコミットを'.(int)$e['count'].'個プッシュしました（'.$commit($e['from']).' → '.$commit($e['to']).'）',
      'merged' => $by.'が「'.$h($e['base']).'」にマージしました（'.$commit($e['commit']).($e['method'] !== 'manual' ? '、'.['merge' => 'マージコミット', 'squash' => 'スカッシュ', 'rebase' => 'リベース'][$e['method']] : '').'）',
      'branchDeleted' => $by.'がブランチ「'.$h($e['branch']).'」を削除しました',
      'reopened' => $by.'が開き直しました',
      'title' => $by.'が題名を「'.$h($e['from']).'」から「'.$h($e['to']).'」に変えました',
      'labels' => $by.'が'.trim(($e['add'] ? 'ラベル'.$list($e['add'], $chip).'を付け' : '').($e['add'] && $e['remove'] ? '、' : '').($e['remove'] ? 'ラベル'.$list($e['remove'], $chip).'を外し' : '')).'ました',
      'assignees' => $by.'が'.($e['add'] ? '担当者に'.$h(implode('、', $e['add'])).'を追加し' : '').($e['add'] && $e['remove'] ? '、' : '').($e['remove'] ? $h(implode('、', $e['remove'])).'を担当者から外し' : '').'ました',
      'milestone' => $e['to'] !== null ? $by.'がマイルストーンを「'.$h($milestones[$e['to']]['title'] ?? '?').'」にしました' : $by.'がマイルストーンを外しました',
      'commit' => $by.'がコミット'.$commit($e['commit']).'「'.$h($e['subject']).'」（'.$h($e['branch']).'）で言及しました',
      default => $h($e['type']),
    };
  }
}