<?php namespace Backend\Classes;

use October\Rain\Html\Helper as HtmlHelper;

/**
 * Form Widget base class
 * Widgets used specifically for forms
 *
 * @package october\backend
 * @author Alexey Bobkov, Samuel Georges
 */
abstract class FormWidgetBase extends WidgetBase
{

    //
    // Configurable properties
    //

    /**
     * @var Model Form model object.
     */
    public $model;

    /**
     * @var array Dataset containing field values, if none supplied model should be used.
     */
    public $data;

    /**
     * @var string Active session key, used for editing forms and deferred bindings.
     */
    public $sessionKey;

    /**
     * @var bool Render this form with uneditable preview data.
     */
    public $previewMode = false;

    /**
     * @var bool Determines if this form field should display comments and labels.
     */
    public $showLabels = true;

    //
    // Object properties
    //

    /**
     * @var FormField Object containing general form field information.
     */
    protected $formField;

    /**
     * @var string Form field name.
     */
    protected $fieldName;

    /**
     * @var string Model attribute to get/set value from.
     */
    protected $valueFrom;

    /**
     * Constructor
     * @param $controller Controller Active controller object.
     * @param $model Model The relevant model to reference.
     * @param $formField FormField Object containing general form field information.
     * @param $configuration array Configuration the relates to this widget.
     */
    public function __construct($controller, $formField, $configuration = [])
    {
        $this->formField = $formField;
        $this->fieldName = $formField->fieldName;
        $this->valueFrom = $formField->valueFrom;

        $this->config = $this->makeConfig($configuration);

        $this->fillFromConfig([
            'model',
            'data',
            'sessionKey',
            'previewMode',
            'showLabels'
        ]);

        parent::__construct($controller, $configuration);
    }

    /**
     * Returns a unique ID for this widget. Useful in creating HTML markup.
     */
    public function getId($suffix = null)
    {
        $id = parent::getId($suffix);
        $id .= '-' . $this->fieldName;
        return HtmlHelper::nameToId($id);
    }

    /**
     * Process the postback value for this widget.
     * @param $value The existing value for this widget.
     * @return string The new value for this widget.
     */
    public function getSaveValue($value)
    {
        return $value;
    }

    /**
     * Returns the value for this form field,
     * supports nesting via HTML array.
     * @return string
     */
    public function getLoadValue()
    {
        $defaultValue = null;

        if (!$this->model->exists) {
            if ($this->formField->defaultFrom) {
                list($model, $attribute) = $this->formField->resolveModelAttribute($this->model, $this->formField->defaultFrom);
                $defaultValue = $model->{$attribute};
            }
            elseif ($this->formField->defaults !== '') {
                $defaultValue = $this->formField->defaults;
            }
        }

        return $this->formField->getValueFromData($this->data ?: $this->model, $defaultValue);
    }

    /**
     * Returns the final model and attribute name of
     * a nested HTML array attribute.
     * Eg: list($model, $attribute) = $this->resolveModelAttribute($this->valueFrom);
     * @param  string $attribute.
     * @return array
     */
    public function resolveModelAttribute($attribute)
    {
        return $this->formField->resolveModelAttribute($this->model, $attribute);
    }

}