<?php

class KBController {

    protected function check_access($f3){
        if(!$f3->exists('SESSION.user')){
            // $f3->set('SESSION.error', 'You don\'t have permission for this ticket.');
            $f3->reroute('/login');
        }
    }

    public function index($f3){

        $this->check_access($f3);
        
        $db = $f3->get('DB');
        $search_term = $f3->get('GET.search');
        $tag_param = $f3->get('GET.tag');

        // base query
        $sql = 'SELECT a.* FROM kb a';
        $args = [];

        if($tag_param){
            $sql .= '
                JOIN kb_tags AS at ON a.id = at.article_id
                JOIN tags t ON at.tag_id = t.id
                WHERE t.name = ?
            ';
            $args[] = $tag_param;

            if($search_term){
                $sql .= ' AND LOWER(a.title) LIKE LOWER(?)';
                $args[] = '%' . $search_term . '%';
            }
        } else if ($search_term){
            $sql .= ' WHERE LOWER(a.title) LIKE LOWER(?)';
            $args[] = '%' . $search_term . '%';
        }

        $sql .= ' ORDER BY a.created_at DESC';

        $articles = $db->exec($sql, $args);

        // render
        $f3->set('articles', $articles);
        $f3->set('content', '../ui/views/kb/index.html');
        echo \Template::instance()->render('../ui/templates/layout.html');
        $f3->clear('SESSION.error');
        
    }

    /**
     * Form to create new article
     */
    public function createForm($f3){
        $this->check_access($f3);

        $db = $f3->get('DB');
        $all_tags = $db->exec('SELECT * FROM tags ORDER BY name ASC');
        $f3->set('all_tags', $all_tags);

        // render
        $f3->set('content', '../ui/views/kb/create.html');
        echo \Template::instance()->render('../ui/templates/layout.html');
        $f3->clear('SESSION.error');

    }

    // handle POST
    public function create($f3){
        $this->check_access($f3);

        $title = $f3->get('POST.title');
        $content = $f3->get('POST.content');
        $created_by = $f3->get('SESSION.user.id');

        $db = $f3->get('DB');

        // insert

        $db->exec(
            'INSERT INTO kb (title, content, created_by, updated_by, created_at, updated_at)
            VALUES (?,?,?,?, NOW(), NOW())',
            [$title, $content, $created_by, $created_by]
        );

        $article_id = $db->lastInsertId();

        // TODO: tags

        $f3->reroute('/kb');
    }

    //

    protected function check_kb_exists($article_id, $db, $f3){
        $articles = $db->exec(
            'SELECT * FROM kb WHERE id = ? LIMIT 1', [$article_id]
        );
        if(!$articles){
            $f3->set('SESSION.error', 'Article not found');
            $f3->reroute('/kb');
        }
        return $articles;
    }

    // view a single
    public function view($f3){
        $this->check_access($f3);
        $article_id = $f3->get('PARAMS.id');
        $db = $f3->get('DB');

        $articles = $this->check_kb_exists($article_id, $db, $f3);

        $article = $articles[0];
        $f3->set('article', $article);

        // TODO: tags
        $tags = $db->exec(
            'SELECT t.* FROM tags AS t
            JOIN kb_tags AS at ON t.id = at.tag_id
            WHERE at.kb_id = ?',
            [$article_id]
        );

        // render
        $f3->set('content', '../ui/views/kb/view.html');
        echo \Template::instance()->render('../ui/templates/layout.html');
        $f3->clear('SESSION.error');
    }

    /**
     * Form to edit existing kb article
     */
    public function editForm($f3){

        $this->check_access($f3);

        $article_id = $f3->get('PARAMS.id');
        $db = $f3->get('DB');

        $articles = $this->check_kb_exists($article_id, $db, $f3);

        $article = $articles[0];
        $f3->set('article', $article);

        // fetch current tags
        $current_tag_ids = $db->exec(
            'SELECT tag_id FROM kb_tags WHERE kb_id = ?', [$article_id]
        );

        $article_tag_ids = array_column($current_tag_ids, 'tag_id');
        $f3->set('article_tag_ids', $article_tag_ids);

        // render
        $f3->set('content', '../ui/views/kb/edit.html');
        echo \Template::instance()->render('../ui/templates/layout.html');
        $f3->clear('SESSION.error');

    }

    /**
     * Handle POST to edit existing article
     */
    public function update($f3){
        $this->check_access($f3);
        $article_id = $f3->get('PARAMS.id');
        $db = $f3->get('DB');

        $articles = $this->check_kb_exists($article_id, $db, $f3);
        $article = $articles[0];

        $title = $f3->get('POST.title');
        $content = $f3->get('POST.content');
        $updated_by = $f3->get('SESSION.user.id');

        $db->exec(
            'UPDATE kb 
            SET title=?, content=?, updated_by =?, updated_at = NOW()
            WHERE id = ?',
            [$title, $content, $updated_by, $article_id]
        );

        // update tags - first delete
        $db->exec('DELETE FROM kb_tags WHERE kb_id = ?', [$article_id]);
        
        $tags_id = $f3->get('POST.tags');
        if(!empty($tags_id) && is_array($tags_id)){
            foreach($tags_id as $tag_id){
                $db->exec(
                    'INSERT IGNORE INTO kb_tags (article_id, tag_id) VALUES (?,?)',
                    [$article_id, $tag_id]
                );
            }
        }

        $f3->reroute('/kb/'.$article_id);

    }


}