<?php

namespace SilverStripe\MultiForm\Models;

use SilverStripe\ORM\DataObject;
use SilverStripe\Security\Member;
use SilverStripe\Security\Security;

/**
 * Serializes one or more {@link MultiFormStep}s into
 * a database object.
 *
 * MultiFormSession also stores the current step, so that
 * the {@link MultiForm} and {@link MultiFormStep} classes
 * know what the current step is.
 *
 */
class MultiFormSession extends DataObject
{
    private static $db = [
        'Hash' => 'Varchar(40)',    // cryptographic hash identification to this session
        'IsComplete' => 'Boolean'   // flag to determine if this session is marked completed
    ];

    private static $has_one = [
        'Submitter' => Member::class,
        'CurrentStep' => MultiFormStep::class
    ];

    private static $has_many = [
        'FormSteps' => MultiFormStep::class
    ];

    private static $table_name = 'MultiFormSession';

    /**
     * Mark this session as completed.
     *
     * This sets the flag "IsComplete" to true,
     * and writes the session back.
     */
    public function markCompleted()
    {
        $this->IsComplete = 1;
        $this->write();
    }

    /**
     * These actions are performed when write() is called on this object.
     */
    public function onBeforeWrite()
    {
        // save submitter if a Member is logged in
        $currentMember = Security::getCurrentUser();
        if (!$this->SubmitterID && $currentMember) {
            $this->SubmitterID = $currentMember->ID;
        }

        parent::onBeforeWrite();
    }

    /**
     * These actions are performed when delete() is called on this object.
     */
    public function onBeforeDelete()
    {
        // delete dependent form steps and relation
        $steps = $this->FormSteps();
        if ($steps) {
            foreach ($steps as $step) {
                if ($step && $step->exists()) {
                    $steps->remove($step);
                    $step->delete();
                    $step->destroy();
                }
            }
        }

        parent::onBeforeDelete();
    }

    public function onAfterWrite()
    {
        parent::onAfterWrite();
        // Create encrypted identification to the session instance if it doesn't exist
        if (!$this->Hash) {
            $this->Hash = sha1($this->ID . '-' . microtime());
            $this->write();
        }
    }
}