<?php
/**
 * The field registry.
 *
 * One place that knows which fields exist. Nothing else in the plugin is allowed
 * to keep a field list of its own.
 *
 * Copyright (c) 2026 Quantum, Serbia. https://2ranq.com
 *
 * This program is free software: you can redistribute it and change it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 2 of the License, or any later version. The full
 * text is in LICENSE.txt, next to this file.
 *
 * @package Ranq_Forms
 */

defined( 'ABSPATH' ) || exit;

/**
 * Ranq_Forms_Fields
 */
class Ranq_Forms_Fields {

	/**
	 * The built fields, by type.
	 *
	 * @var array<string, Ranq_Forms_Field>
	 */
	private static $fields = array();

	/**
	 * Whether the registry is already filled.
	 *
	 * @var bool
	 */
	private static $loaded = false;

	/**
	 * Fills the registry. Done once per request, and lazily.
	 *
	 * @return void
	 */
	private static function load() {

		if ( self::$loaded ) {
			return;
		}

		self::$loaded = true;

		require_once RANQ_FORMS_DIR . 'includes/fields/abstract-ranq-forms-field.php';
		require_once RANQ_FORMS_DIR . 'includes/fields/abstract-ranq-forms-field-choices.php';
		require_once RANQ_FORMS_DIR . 'includes/fields/abstract-ranq-forms-field-input.php';

		// The order here is the order in the builder. What is used most often first.
		$classes = array(
			'Ranq_Forms_Field_Text'     => 'class-ranq-forms-field-text.php',
			'Ranq_Forms_Field_Textarea' => 'class-ranq-forms-field-textarea.php',
			'Ranq_Forms_Field_Email'    => 'class-ranq-forms-field-email.php',
			'Ranq_Forms_Field_Number'   => 'class-ranq-forms-field-number.php',
			'Ranq_Forms_Field_Select'   => 'class-ranq-forms-field-select.php',
			'Ranq_Forms_Field_Checkbox' => 'class-ranq-forms-field-checkbox.php',
			'Ranq_Forms_Field_Radio'    => 'class-ranq-forms-field-radio.php',
			'Ranq_Forms_Field_Imagechoice' => 'class-ranq-forms-field-imagechoice.php',
			'Ranq_Forms_Field_Ranking'  => 'class-ranq-forms-field-ranking.php',

			'Ranq_Forms_Field_Name'     => 'class-ranq-forms-field-name.php',
			'Ranq_Forms_Field_Phone'    => 'class-ranq-forms-field-phone.php',
			'Ranq_Forms_Field_Address'  => 'class-ranq-forms-field-address.php',
			'Ranq_Forms_Field_Url'      => 'class-ranq-forms-field-url.php',
			'Ranq_Forms_Field_Date'     => 'class-ranq-forms-field-date.php',
			'Ranq_Forms_Field_Time'     => 'class-ranq-forms-field-time.php',
			'Ranq_Forms_Field_Password' => 'class-ranq-forms-field-password.php',
			'Ranq_Forms_Field_Rating'   => 'class-ranq-forms-field-rating.php',
			'Ranq_Forms_Field_Signature' => 'class-ranq-forms-field-signature.php',
			'Ranq_Forms_Field_File'     => 'class-ranq-forms-field-file.php',

			'Ranq_Forms_Field_Pagebreak' => 'class-ranq-forms-field-pagebreak.php',
			'Ranq_Forms_Field_Content'  => 'class-ranq-forms-field-content.php',
			'Ranq_Forms_Field_Divider'  => 'class-ranq-forms-field-content.php',
			'Ranq_Forms_Field_Hidden'   => 'class-ranq-forms-field-content.php',
		);

		foreach ( $classes as $class => $file ) {

			require_once RANQ_FORMS_DIR . 'includes/fields/' . $file;

			/**
			 * The field.
			 *
			 * @var Ranq_Forms_Field $field
			 */
			$field = new $class();

			self::$fields[ $field->get_type() ] = $field;
		}

		/**
		 * Adding fields from modules and from outside.
		 *
		 * The hook has been there since day one. A module that adds a field does
		 * not touch the core.
		 *
		 * @param array<string, Ranq_Forms_Field> $fields Fields by type.
		 */
		self::$fields = apply_filters( 'ranq_forms_fields', self::$fields );
	}

	/**
	 * Every field.
	 *
	 * @return array<string, Ranq_Forms_Field>
	 */
	public static function all() {

		self::load();

		return self::$fields;
	}

	/**
	 * A single field by type, or null when that type does not exist.
	 *
	 * @param string $type The field type.
	 *
	 * @return Ranq_Forms_Field|null
	 */
	public static function get( $type ) {

		self::load();

		$type = sanitize_key( $type );

		return isset( self::$fields[ $type ] ) ? self::$fields[ $type ] : null;
	}

	/**
	 * The fields of one form, the way they were saved.
	 *
	 * @param int $form_id The form id.
	 *
	 * @return array
	 */
	public static function get_form_fields( $form_id ) {

		$saved = get_post_meta( absint( $form_id ), '_ranq_forms_fields', true );

		if ( ! is_array( $saved ) ) {
			return array();
		}

		return $saved;
	}
}