<?php
namespace Misuzu\Forum;

use stdClass;
use RuntimeException;
use Index\Http\{HttpRequest,HttpResponseBuilder};
use Index\Http\Routing\{HttpGet,HttpPost,RouteHandler,RouteHandlerCommon};
use Index\Urls\{UrlFormat,UrlSource,UrlSourceCommon};
use Misuzu\{CSRF,Pagination,Perm,Template};
use Misuzu\Auth\AuthInfo;
use Misuzu\Users\UsersContext;

class ForumCategoriesRoutes implements RouteHandler, UrlSource {
    use RouteHandlerCommon, UrlSourceCommon;

    public function __construct(
        private ForumContext $forum,
        private UsersContext $usersCtx,
        private AuthInfo $authInfo,
    ) {}

    #[HttpGet('/forum')]
    #[UrlFormat('forum-index', '/forum')]
    #[UrlFormat('forum-category-root', '/forum', fragment: '<forum>')]
    public function getIndex(): string {
        $cats = $this->forum->categories->getCategories(hidden: false, asTree: true);

        // Filtering! This really needs cleaning up...
        foreach($cats as $catId => $category) {
            $perms = $this->authInfo->getPerms('forum', $category->info);

            // Check if we're allowed to list this category, separate from viewing for some reason...
            if(!$perms->check(Perm::F_CATEGORY_LIST)) {
                unset($cats[$catId]);
                continue;
            }

            $unread = false;

            // This is not fully recursive, idk why... probably shove this into ForumContext?
            if($category->info->mayHaveChildren)
                foreach($category->children as $childId => $child) {
                    $childPerms = $this->authInfo->getPerms('forum', $child->info);
                    if(!$childPerms->check(Perm::F_CATEGORY_LIST)) {
                        unset($category->children[$childId]);
                        continue;
                    }

                    $childUnread = false;

                    if($category->info->isListing) {
                        if($child->info->mayHaveChildren) {
                            foreach($child->children as $grandChildId => $grandChild) {
                                $grandChildPerms = $this->authInfo->getPerms('forum', $grandChild->info);
                                if(!$grandChildPerms->check(Perm::F_CATEGORY_LIST)) {
                                    unset($child->children[$grandChildId]);
                                    continue;
                                }

                                $grandChildUnread = false;

                                if($grandChild->info->mayHaveTopics) {
                                    $catIds = [$grandChild->info->id];
                                    foreach($grandChild->childIds as $greatGrandChildId) {
                                        $greatGrandChildPerms = $this->authInfo->getPerms('forum', $greatGrandChildId);
                                        if($greatGrandChildPerms->check(Perm::F_CATEGORY_LIST))
                                            $catIds[] = $greatGrandChildId;
                                    }

                                    $grandChildUnread = $this->forum->categories->checkCategoryUnread($catIds, $this->authInfo->userInfo);
                                    if($grandChildUnread)
                                        $childUnread = true;
                                }

                                $grandChild->perms = $grandChildPerms;
                                $grandChild->unread = $grandChildUnread;
                            }
                        }

                        if($child->info->mayHaveChildren || $child->info->mayHaveTopics) {
                            $catIds = [$child->info->id];
                            foreach($child->childIds as $grandChildId) {
                                $grandChildPerms = $this->authInfo->getPerms('forum', $grandChildId);
                                if($grandChildPerms->check(Perm::F_CATEGORY_LIST))
                                    $catIds[] = $grandChildId;
                            }

                            try {
                                $lastPostInfo = $this->forum->posts->getPost(categoryInfos: $catIds, getLast: true, deleted: false);
                            } catch(RuntimeException $ex) {
                                $lastPostInfo = null;
                            }

                            if($lastPostInfo !== null) {
                                $child->lastPost = new stdClass;
                                $child->lastPost->info = $lastPostInfo;
                                $child->lastPost->topicInfo = $this->forum->topics->getTopic(postInfo: $lastPostInfo);

                                if($lastPostInfo->userId !== null) {
                                    $child->lastPost->user = $this->usersCtx->getUserInfo($lastPostInfo->userId);
                                    $child->lastPost->colour = $this->usersCtx->getUserColour($child->lastPost->user);
                                }
                            }
                        }
                    }

                    if($child->info->mayHaveTopics && !$childUnread) {
                        $childUnread = $this->forum->categories->checkCategoryUnread($child->info, $this->authInfo->userInfo);
                        if($childUnread)
                            $unread = true;
                    }

                    $child->perms = $childPerms;
                    $child->unread = $childUnread;
                }

            // This is listed second despite being less expensive because the subcategories listed also need to show unread :sob:
            if($category->info->mayHaveTopics)
                $unread = $this->forum->categories->checkCategoryUnread($category->info, $this->authInfo->userInfo);

            // Create virtual root category if we need to list non-listing categories in root
            if(!$category->info->isListing) {
                if(!array_key_exists('0', $cats)) {
                    $cats['0'] = $root = new stdClass;
                    $root->info = null;
                    $root->perms = 0;
                    $root->unread = false;
                    $root->colour = null;
                    $root->children = [];
                }

                $cats['0']->children[$category->id] = $category;
                unset($cats[$category->id]);

                if($category->info->mayHaveChildren || $category->info->mayHaveTopics) {
                    $catIds = [$category->info->id];
                    foreach($category->childIds as $childId) {
                        $childPerms = $this->authInfo->getPerms('forum', $childId);
                        if($childPerms->check(Perm::F_CATEGORY_LIST))
                            $catIds[] = $childId;
                    }

                    try {
                        $lastPostInfo = $this->forum->posts->getPost(categoryInfos: $catIds, getLast: true, deleted: false);
                    } catch(RuntimeException $ex) {
                        $lastPostInfo = null;
                    }

                    if($lastPostInfo !== null) {
                        $category->lastPost = new stdClass;
                        $category->lastPost->info = $lastPostInfo;
                        $category->lastPost->topicInfo = $this->forum->topics->getTopic(postInfo: $lastPostInfo);

                        if($lastPostInfo->userId !== null) {
                            $category->lastPost->user = $this->usersCtx->getUserInfo($lastPostInfo->userId);
                            $category->lastPost->colour = $this->usersCtx->getUserColour($category->lastPost->user);
                        }
                    }
                }
            }

            $category->perms = $perms;
            $category->unread = $unread;
        }

        return Template::renderRaw('forum.index', [
            'forum_categories' => $cats,
            'forum_empty' => empty($cats),
            'forum_show_mark_as_read' => $this->authInfo->isLoggedIn,
        ]);
    }

    #[HttpGet('/forum/([0-9]+)')]
    #[UrlFormat('forum-category', '/forum/<forum>', ['page' => '<page>'])]
    public function getCategory(HttpResponseBuilder $response, HttpRequest $request, string $catId): mixed {
        try {
            $category = $this->forum->categories->getCategory(categoryId: $catId);
        } catch(RuntimeException $ex) {
            return 404;
        }

        $perms = $this->authInfo->getPerms('forum', $category);
        if(!$perms->check(Perm::F_CATEGORY_VIEW))
            return 403;

        if($category->isLink) {
            $this->forum->categories->incrementCategoryClicks($category);
            $response->redirect($category->linkTarget ?? '/');
            return 301;
        }

        if($this->usersCtx->hasActiveBan($this->authInfo->userInfo))
            $perms = $perms->apply(fn(int $calc) => $calc & (Perm::F_CATEGORY_LIST | Perm::F_CATEGORY_VIEW));

        $pagination = Pagination::fromRequest($request, $this->forum->topics->countTopics(
            categoryInfo: $category,
            global: true,
            deleted: $perms->check(Perm::F_POST_DELETE_ANY) ? null : false
        ), 20);
        if(!$pagination->validOffset)
            return 404;

        $children = [];
        $topics = [];

        if($category->mayHaveChildren) {
            $children = $this->forum->categories->getCategoryChildren($category, hidden: false, asTree: true);

            foreach($children as $childId => $child) {
                $childPerms = $this->authInfo->getPerms('forum', $child->info);
                if(!$childPerms->check(Perm::F_CATEGORY_LIST)) {
                    unset($children[$childId]);
                    continue;
                }

                $childUnread = false;

                if($child->info->mayHaveChildren) {
                    foreach($child->children as $grandChildId => $grandChild) {
                        $grandChildPerms = $this->authInfo->getPerms('forum', $grandChild->info);
                        if(!$grandChildPerms->check(Perm::F_CATEGORY_LIST)) {
                            unset($child->children[$grandChildId]);
                            continue;
                        }

                        $grandChildUnread = false;

                        if($grandChild->info->mayHaveTopics) {
                            $catIds = [$grandChild->info->id];
                            foreach($grandChild->childIds as $greatGrandChildId) {
                                $greatGrandChildPerms = $this->authInfo->getPerms('forum', $greatGrandChildId);
                                if(!$greatGrandChildPerms->check(Perm::F_CATEGORY_LIST))
                                    $catIds[] = $greatGrandChildId;
                            }

                            $grandChildUnread = $this->forum->categories->checkCategoryUnread($catIds, $this->authInfo->userInfo);
                            if($grandChildUnread)
                                $childUnread = true;
                        }

                        $grandChild->perms = $grandChildPerms;
                        $grandChild->unread = $grandChildUnread;
                    }
                }

                if($child->info->mayHaveChildren || $child->info->mayHaveTopics) {
                    $catIds = [$child->info->id];
                    foreach($child->childIds as $grandChildId) {
                        $grandChildPerms = $this->authInfo->getPerms('forum', $grandChildId);
                        if($grandChildPerms->check(Perm::F_CATEGORY_LIST))
                            $catIds[] = $grandChildId;
                    }

                    try {
                        $lastPostInfo = $this->forum->posts->getPost(categoryInfos: $catIds, getLast: true, deleted: false);
                    } catch(RuntimeException $ex) {
                        $lastPostInfo = null;
                    }

                    if($lastPostInfo !== null) {
                        $child->lastPost = new stdClass;
                        $child->lastPost->info = $lastPostInfo;
                        $child->lastPost->topicInfo = $this->forum->topics->getTopic(postInfo: $lastPostInfo);

                        if($lastPostInfo->userId !== null) {
                            $child->lastPost->user = $this->usersCtx->getUserInfo($lastPostInfo->userId);
                            $child->lastPost->colour = $this->usersCtx->getUserColour($child->lastPost->user);
                        }
                    }
                }

                if($child->info->mayHaveTopics && !$childUnread)
                    $childUnread = $this->forum->categories->checkCategoryUnread($child->info, $this->authInfo->userInfo);

                $child->perms = $childPerms;
                $child->unread = $childUnread;
            }
        }

        if($category->mayHaveTopics) {
            $topicInfos = $this->forum->topics->getTopics(
                categoryInfo: $category,
                global: true,
                deleted: $perms->check(Perm::F_POST_DELETE_ANY) ? null : false,
                pagination: $pagination,
            );

            foreach($topicInfos as $topicInfo) {
                $topics[] = $topic = new stdClass;
                $topic->info = $topicInfo;
                $topic->unread = $this->forum->topics->checkTopicUnread($topicInfo, $this->authInfo->userInfo);
                $topic->participated = $this->forum->topics->checkTopicParticipated($topicInfo, $this->authInfo->userInfo);

                if($topicInfo->userId !== null) {
                    $topic->user = $this->usersCtx->getUserInfo($topicInfo->userId);
                    $topic->colour = $this->usersCtx->getUserColour($topic->user);
                }

                try {
                    $topic->lastPost = new stdClass;
                    $topic->lastPost->info = $lastPostInfo = $this->forum->posts->getPost(
                        topicInfo: $topicInfo,
                        getLast: true,
                        deleted: $topicInfo->deleted ? null : false,
                    );

                    if($lastPostInfo->userId !== null) {
                        $topic->lastPost->user = $this->usersCtx->getUserInfo($lastPostInfo->userId);
                        $topic->lastPost->colour = $this->usersCtx->getUserColour($topic->lastPost->user);
                    }
                } catch(RuntimeException $ex) {
                    $topic->lastPost = null;
                }
            }
        }

        return Template::renderRaw('forum.forum', [
            'forum_breadcrumbs' => iterator_to_array($this->forum->categories->getCategoryAncestry($category)),
            'global_accent_colour' => $this->forum->categories->getCategoryColour($category),
            'forum_info' => $category,
            'forum_children' => $children,
            'forum_topics' => $topics,
            'forum_pagination' => $pagination,
            'forum_show_mark_as_read' => $this->authInfo->isLoggedIn,
            'forum_perms' => $perms->checkMany([
                'can_create_topic' => Perm::F_TOPIC_CREATE,
            ]),
        ]);
    }

    #[HttpPost('/forum/mark-as-read')]
    #[UrlFormat('forum-mark-as-read', '/forum/mark-as-read', ['cat' => '<category>', 'rec' => '<recursive>'])]
    public function postMarkAsRead(HttpResponseBuilder $response, HttpRequest $request): mixed {
        if(!$this->authInfo->isLoggedIn)
            return 401;

        if(!CSRF::validate($request->getHeaderLine('X-CSRF-token')))
            return 403;
        $response->setHeader('X-CSRF-Token', CSRF::token());

        $catId = (string)$request->getParam('cat', FILTER_SANITIZE_NUMBER_INT);
        $recursive = !empty($request->getParam('rec'));

        if($catId === '') {
            if(!$recursive)
                return 400;

            $cats = $this->forum->categories->getCategories();
        } elseif($recursive)
            $cats = $this->forum->categories->getCategoryChildren(parentInfo: $catId, includeSelf: true);
        else
            try {
                $cats = [$this->forum->categories->getCategory(categoryId: $catId)];
            } catch(RuntimeException $ex) {
                $cats = [];
            }

        if(empty($cats)) {
            $response->statusCode = 404;
            return [
                'error' => [
                    'name' => 'forum:category:none',
                    'text' => "Couldn't find that forum category.",
                ],
            ];
        }

        $success = false;
        foreach($cats as $category) {
            $perms = $this->authInfo->getPerms('forum', $category);
            if($perms->check(Perm::F_CATEGORY_LIST)) {
                $this->forum->categories->updateUserReadCategory($this->authInfo->userInfo, $category);
                $success = true;
            }
        }

        if(!$success) {
            $response->statusCode = 403;
            return [
                'error' => [
                    'name' => 'forum:category:access',
                    'text' => "You're not allowed to access this forum category.",
                ],
            ];
        }

        return 204;
    }
}