<?php
/**
 * Guild skill group entity file.
 *
 * Creates the entity and makes it available.
 *
 * @author Iñigo Valentin <i@inigovalentin.com>
 * @license https://www.gnu.org/licenses/gpl-3.0.en.html GNU General Public License V3
 * @package SWDB
 */

require_once(PATH::ENTITY . "Entity.php");
require_once(PATH::ENTITY . "Guild_Skill.php");

/**
 * Guild skill group.
 *
 * Represents a category of guild skills.
 *
 * @category Entity
 */
class Guild_Skill_Group extends Entity{

    /**
     * @var int Group ID.
     */
    private $id;

    /**
     * @var string Group name.
     */
    private $name;

    /**
     * @var string Group description.
     */
    private $description;

    /**
     * @var bool Internal flag to check if the group skills have been loaded into the entity.
     */
    private $flag_skills = false;

    /**
     * @var Guild_Skill[] Skills in the group.
     */
    private $skills = [];

    /**
     * Constructor.
     *
     * Searches the database and retrieves the information about the
     * skill group, populating it and it's items.
     *
     * @param int $id Skill group identifier.
     */
    public function __construct($id){

        $statement = get_context()->get_db()->prepare("
          SELECT
            id,
            name,
            description
          FROM guild_skill_group
          WHERE id = :id;
        ");
        $statement->bindValue(':id', $id, SQLITE3_TEXT);
        $r = $statement->execute()->fetchArray(SQLITE3_ASSOC);
        if ($r){
            $this->id = $r["id"];
            $this->name = HTML::e($r["name"]);
            $this->description = HTML::e($r["description"]);
        }
    }

    /**
     * Loads the skills in the group.
     *
     * Must be called only once before trying to get the skills. Sets the flag
     * {@link Guild_Skill_Group:$flag_skills} to true.
     */
    private function load_skills(){
        $statement = get_context()->get_db()->prepare("
          SELECT id
          FROM guild_skill
          WHERE skill_group = :id;
        ");
        $statement->bindValue(':id', $this->id, SQLITE3_TEXT);
        $q = $statement->execute();
        while ($r = $q->fetchArray(SQLITE3_ASSOC)){
            array_push($this->skills, new Guild_Skill($r["id"]));
        }
        $this->flag_skills = true;
    }

    /**
     * Retrieves the identifier of the skill group.
     *
     * @return int Group ID
     */
    public function get_id(){
        return $this->id;
    }

    /**
     * Retrieves the name of the skill_group.
     *
     * @return string Group name.
     */
    public function get_name(){
        return $this->name;
    }

    /**
     * Retrieves the description of the skill group.
     *
     * @return string Group description.
     */
    public function get_description(){
        return $this->description;
    }

    /**
     * Retrieves the skills in the group.
     *
     * @return Guild_Skill[] Skills in the group.
     */
    public function get_skills(){
        if (! $this->flag_skills){
            $this->load_skills();
        }
        return $this->skills;
    }

    /**
     * Gets the pathto the skill group image.
     *
     * @return string Image URL, or a fixed unknown image.
     */
    public function get_image(){
        return APPLICATION::img("SKILL_GUILD", $this->id);
    }

}