<?php namespace BookStack;


class Entity extends Ownable
{

    /**
     * Compares this entity to another given entity.
     * Matches by comparing class and id.
     * @param $entity
     * @return bool
     */
    public function matches($entity)
    {
        return [get_class($this), $this->id] === [get_class($entity), $entity->id];
    }

    /**
     * Checks if an entity matches or contains another given entity.
     * @param Entity $entity
     * @return bool
     */
    public function matchesOrContains(Entity $entity)
    {
        $matches = [get_class($this), $this->id] === [get_class($entity), $entity->id];

        if ($matches) return true;

        if (($entity->isA('chapter') || $entity->isA('page')) && $this->isA('book')) {
            return $entity->book_id === $this->id;
        }

        if ($entity->isA('page') && $this->isA('chapter')) {
            return $entity->chapter_id === $this->id;
        }

        return false;
    }

    /**
     * Gets the activity objects for this entity.
     * @return \Illuminate\Database\Eloquent\Relations\MorphMany
     */
    public function activity()
    {
        return $this->morphMany(Activity::class, 'entity')->orderBy('created_at', 'desc');
    }

    /**
     * Get View objects for this entity.
     */
    public function views()
    {
        return $this->morphMany(View::class, 'viewable');
    }

    /**
     * Get the Tag models that have been user assigned to this entity.
     * @return \Illuminate\Database\Eloquent\Relations\MorphMany
     */
    public function tags()
    {
        return $this->morphMany(Tag::class, 'entity')->orderBy('order', 'asc');
    }

    /**
     * Get this entities restrictions.
     */
    public function permissions()
    {
        return $this->morphMany(EntityPermission::class, 'restrictable');
    }

    /**
     * Check if this entity has a specific restriction set against it.
     * @param $role_id
     * @param $action
     * @return bool
     */
    public function hasRestriction($role_id, $action)
    {
        return $this->permissions()->where('role_id', '=', $role_id)
            ->where('action', '=', $action)->count() > 0;
    }

    /**
     * Check if this entity has live (active) restrictions in place.
     * @param $role_id
     * @param $action
     * @return bool
     */
    public function hasActiveRestriction($role_id, $action)
    {
        return $this->getRawAttribute('restricted') && $this->hasRestriction($role_id, $action);
    }

    /**
     * Get the entity jointPermissions this is connected to.
     * @return \Illuminate\Database\Eloquent\Relations\MorphMany
     */
    public function jointPermissions()
    {
        return $this->morphMany(JointPermission::class, 'entity');
    }

    /**
     * Allows checking of the exact class, Used to check entity type.
     * Cleaner method for is_a.
     * @param $type
     * @return bool
     */
    public static function isA($type)
    {
        return static::getType() === strtolower($type);
    }

    /**
     * Get entity type.
     * @return mixed
     */
    public static function getType()
    {
        return strtolower(static::getClassName());
    }

    /**
     * Get an instance of an entity of the given type.
     * @param $type
     * @return Entity
     */
    public static function getEntityInstance($type)
    {
        $types = ['Page', 'Book', 'Chapter'];
        $className = str_replace([' ', '-', '_'], '', ucwords($type));
        if (!in_array($className, $types)) {
            return null;
        }

        return app('BookStack\\' . $className);
    }

    /**
     * Gets a limited-length version of the entities name.
     * @param int $length
     * @return string
     */
    public function getShortName($length = 25)
    {
        if (strlen($this->name) <= $length) return $this->name;
        return substr($this->name, 0, $length - 3) . '...';
    }

    /**
     * Perform a full-text search on this entity.
     * @param string[] $fieldsToSearch
     * @param string[] $terms
     * @param string[] array $wheres
     * @return mixed
     */
    public function fullTextSearchQuery($fieldsToSearch, $terms, $wheres = [])
    {
        $exactTerms = [];
        $fuzzyTerms = [];
        $search = static::newQuery();
        foreach ($terms as $key => $term) {
            $safeTerm = htmlentities($term, ENT_QUOTES);
            $safeTerm = preg_replace('/[+\-><\(\)~*\"@]+/', ' ', $safeTerm);
            if (preg_match('/&quot;.*?&quot;/', $safeTerm) || is_numeric($safeTerm)) {
                $safeTerm = preg_replace('/^"(.*?)"$/', '$1', $term);
                $exactTerms[] = '%' . $safeTerm . '%';
            } else {
                $safeTerm = '' . $safeTerm . '*';
                if (trim($safeTerm) !== '*') $fuzzyTerms[] = $safeTerm;
            }
        }
        $isFuzzy = count($exactTerms) === 0 || count($fuzzyTerms) > 0;

        // Perform fulltext search if relevant terms exist.
        if ($isFuzzy) {
            $termString = implode(' ', $fuzzyTerms);
            $fields = implode(',', $fieldsToSearch);
            $search = $search->selectRaw('*, MATCH(name) AGAINST(? IN BOOLEAN MODE) AS title_relevance', [$termString]);
            $search = $search->whereRaw('MATCH(' . $fields . ') AGAINST(? IN BOOLEAN MODE)', [$termString]);
        }

        // Ensure at least one exact term matches if in search
        if (count($exactTerms) > 0) {
            $search = $search->where(function ($query) use ($exactTerms, $fieldsToSearch) {
                foreach ($exactTerms as $exactTerm) {
                    foreach ($fieldsToSearch as $field) {
                        $query->orWhere($field, 'like', $exactTerm);
                    }
                }
            });
        }
        $orderBy = $isFuzzy ? 'title_relevance' : 'updated_at';

        // Add additional where terms
        foreach ($wheres as $whereTerm) {
            $search->where($whereTerm[0], $whereTerm[1], $whereTerm[2]);
        }

        // Load in relations
        if ($this->isA('page')) {
            $search = $search->with('book', 'chapter', 'createdBy', 'updatedBy');
        } else if ($this->isA('chapter')) {
            $search = $search->with('book');
        }

        return $search->orderBy($orderBy, 'desc');
    }

}