<?php

/*
 * SCROTT 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 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.
 *
 * For more information, please refer to UNLICENSE
 */

require_once "class/object.class.php";
require_once "class/pad.class.php";

/*
 * This class models Scrott pad stages.  Stages form a pipeline through
 * which issues can progress.
 */
class stage extends object
{
    /*
     * Constructor
     */
    public function __construct(?string $guid = NULL)
    {
        $this->fields['stages'] = array(
            "guid",
            "stage",
        );

        parent::__construct($guid);
        $this->expectType("stage");
    }

    /*
     * Initialize a new stage object with the given name and parent
     * pad.
     */
    public static function initNew(string $name, pad $parent) : stage
    {
        $stage = new stage();
        $stage->setParent($parent);
        $stage->name = $name;
        $stage->objtype = "stage";
        return $stage;
    }

    /*
     * Get the stage following this one in the pipeline.  NULL is
     * returned if no stage is next.
     */
    public function getNext() : ?stage
    {
        if (!isset($this->stage) || $this->stage == "")
            return NULL;

        return new stage($this->stage);
    }

    /*
     * Get the stage preceding this one in the pipeline.  NULL is
     * returned if no stage is previous.
     */
    public function getPrev() : ?stage
    {
        $pad = new pad($this->getParent());

        if ($pad->stage == $this->guid)
            return NULL;

        $query = "SELECT guid FROM stages WHERE stage = '" . database::esc($this->guid) . "'";
        $res = database::query($query);

        if (count($res) == 0)
            return NULL;

        return new stage($res[0]['guid']);
    }

    /*
     * Get an array of all stages reachable from this one.  The array
     * is in proper order and includes the current stage.
     */
    public function getArray() : array
    {
        $stages = array();
        $curr = $this;

        do $stages[] = $curr;
        while (($curr = $curr->getNext()));

        return $stages;
    }

    /*
     * Reorder the stages of a pipeline by moving this one forward.
     * This swaps the places of the current stage and the one following
     * it.  If this stage is the last in its pipeline, nothing is done
     * and false is returned.
     */
    public function moveForward() : bool
    {
        if (!($next = $this->getNext()))
            return false;

        if (!($prev = $this->getPrev()))
            $prev = new pad($this->getParent());

        $tmp = $next->stage;
        $prev->stage = $next->guid;
        $next->stage = $this->guid;
        $this->stage = $tmp;

        $next->saveObj();
        $prev->saveObj();
        return true;
    }

    /*
     * Reorder the stages of a pipeline by moving this one backward.
     * This swaps the places of the current stage and the one preceding
     * it.  If this stage is the first in its pipeline, nothing is done
     * and false is returned.
     */
    public function moveBackward() : bool
    {
        if (!($prev = $this->getPrev()))
            return false;

        return $prev->moveForward();
    }
}

?>