<?php

class WPML_ACF_Field_Settings {

	/**
	 * @var array Translation Managament settings indexes which should be updated.
	 */
	private $tm_setting_index = [ 'custom_fields_translation', 'custom_term_fields_translation' ];

	/**
	 * @var TranslationManagement TranslationManagement object.
	 */
	private $translation_management;

	/**
	 * WPML_ACF_Field_Settings constructor.
	 *
	 * @param TranslationManagement $translation_management TranslationManagement object.
	 */
	public function __construct( TranslationManagement $translation_management ) {
		$this->translation_management = $translation_management;
	}

	/**
	 * Register WordPress hooks related to ACF field settings.
	 */
	public function add_hooks() {
		// add radio buttons on Field Group page.
		add_action( 'acf/render_field_settings', array( $this, 'render_field_settings'), 10, 1);

		// same as above run when user is changing field type on field group edit screen.
		if ( function_exists( 'acf_maybe_get_POST' ) ) {
			$field = acf_maybe_get_POST('field');
			if ( isset( $field['type'] ) ) {
				add_action( "acf/render_field_settings/type={$field['type']}", array( $this, 'render_field_settings'), 10, 1);
			}
		}

		// handle setting sync preferences on Field Group page.
		add_filter( 'acf/update_field', array( $this, 'update_field_settings' ), 10, 1);

		// when user adds new field value on post edit screen.
		add_filter( 'acf/update_value', array( $this, 'field_value_updated'), 10, 4 );

		// use case when user updates sync prefernces on post edit screen.
		add_action( 'wpml_single_custom_field_sync_option_updated', array($this, 'user_set_sync_preferences'), 10, 1);
		add_action( 'wpml_custom_fields_sync_option_updated', array($this, 'user_set_sync_preferences'), 10, 1);

		// mark field as not migrated yet.
		add_filter( 'acf/get_field_label', array( $this, 'mark_not_migrated_field' ), 10, 2 );

		// repeater and flexible fields hsould be set to Copy.
		add_filter( 'acf/get_field_label', array( $this, 'adviceToSetCopyForField' ), 10, 2 );
	}

	/**
	 * Adds new row to ACF field configuration screen.
	 *
	 * Adds options to set translation prefreences for the field. If the field should
	 * be always copied, does not add anything.
	 *
	 * @param array $field ACF field array.
	 */
	public function render_field_settings( $field ) {
		acf_render_field_setting( $field, array(
			'label'			=> __('Translation preferences','acfml'),
			'instructions'	=> __('What to do with field\'s value when post/page is going to be translated','acf'),
			'type'			=> 'radio',
			'name'			=> 'wpml_cf_preferences',
			'layout'		=> 'horizontal',
			'choices'		=> array(
				WPML_IGNORE_CUSTOM_FIELD	=> __("Don't translate",'acfml'),
				WPML_COPY_CUSTOM_FIELD		=> __("Copy",'acfml'),
				WPML_COPY_ONCE_CUSTOM_FIELD => __("Copy once", 'acfml'),
				WPML_TRANSLATE_CUSTOM_FIELD => __("Translate", "acfml")
			)
		));
	}

	public function update_field_settings( $field ) {

		if ( $this->is_field_parsable( $field ) ) {
			$this->update_existing_subfields( $field );
			$this->save_field_settings( $field );
		}

		return $field;
	}

	/**
	 * Synchronise translation preferences when user adds new field value on post edit screen.
	 *
	 * @param mixed $value   Field value being updated.
	 * @param int   $post_id The ID of currrent post being updated.
	 * @param array $field   The ACF field.
	 * @param null  $_value  Deprecated.
	 *
	 * @return mixed
	 */
	public function field_value_updated( $value, $post_id, $field, $_value = null ) {
		if ( $this->is_field_parsable( $field ) ) {
			if ( ! isset( $this->translation_management->settings['custom_fields_translation'][ $field['name'] ] ) ) {
				$this->save_field_settings( $field );
			}
		}

		return $value;
	}

	/**
	 * Checks if field has all required elements or is the field which always should be set to copy.
	 *
	 * @param array $field ACF field data.
	 *
	 * @return bool
	 */
	private function is_field_parsable( $field ) {
		return ( isset( $field['wpml_cf_preferences'], $field['name'] ) && $field['wpml_cf_preferences'] && $field['name'] )
			|| $this->field_should_be_set_to_copy( $field );
	}

	/**
	 * Save translation preferences for custom field in Translation Management settings.
	 *
	 * @param array $field The ACF field being updated.
	 */
	private function save_field_settings( $field ) {
		foreach ( $this->tm_setting_index as $setting_index ) {
			$this->translation_management->settings[ $setting_index ][ $field['name'] ] = $field['wpml_cf_preferences'];
		}
		if ( (int) $field['wpml_cf_preferences'] !== WPML_IGNORE_CUSTOM_FIELD ) {
			$this->update_corresponding_system_field_settings( $field['name'] );
		}
		$this->translation_management->save_settings();
	}

	/**
	 * Synchronises custom field translation preferences saved on post edit screen.
	 *
	 * @param array $cft Custom fields translation preferences.
	 */
	public function user_set_sync_preferences($cft) {

		foreach ( $cft as $field_name => $field_preferences ) {
			$post_id = $this->get_post_with_custom_field( $field_name );
			$field_object = get_field_object( $field_name, $post_id );

			if ( $this->is_field_object_valid( $field_object ) ) {
				if ( $field_object['wpml_cf_preferences'] != $field_preferences ) {
					$field_post = get_post( $field_object['ID'] );
					$field_post_content = maybe_unserialize( $field_post->post_content );
					$field_post_content['wpml_cf_preferences'] = $field_preferences;
					wp_update_post( array(
						'ID' => $field_object['ID'],
						'post_content' => maybe_serialize( $field_post_content )
					) );
				}
			}
		}

		// this action runs also for case 'icl_tcf_translation', @see \TranslationManagement::ajax_calls
		// it shouldn't because it will overwrite normal cf fields values with zeros
		remove_action( 'wpml_custom_fields_sync_option_updated', array( $this, 'user_set_sync_preferences' ), 10, 1);
	}

	/**
	 * Validates ACF field object.
	 *
	 * @param array $field_object The ACF field object.
	 *
	 * @return bool
	 */
	private function is_field_object_valid( $field_object ) {
		return is_array( $field_object ) && is_numeric( $field_object['ID'] ) && $field_object['ID'] > 0;
	}

	/**
	 * Get ID of post having given ACF field.
	 *
	 * @param string $field_name ACF field name.
	 *
	 * @return object|string|void|null
	 */
	private function get_post_with_custom_field($field_name) {
		$post_id = get_the_ID() ?: get_queried_object();
		if (!is_numeric($post_id)) {
			global $wpdb;
			$query = "SELECT post_id FROM {$wpdb->postmeta} WHERE meta_key = '{$field_name}' LIMIT 1";
			$post_id = $wpdb->get_var($query);
		}
		return $post_id;
	}

	/**
	 * Find current field subfields and udpate their translation preferences.
	 *
	 * @param array $field The ACF field.
	 */
	private function update_existing_subfields( $field ) {
		if ( isset( $field['parent'] ) ) {
			$parent_post_type = get_post_type( $field['parent'] );
			if ( "acf-field" == $parent_post_type) { // yes, it is subfield
				global $wpdb;
				$query = "SELECT * FROM {$wpdb->postmeta} WHERE meta_key LIKE %s";
				$prepared = $wpdb->prepare( $query, "%" . $wpdb->esc_like( $field['name'] ) );
				$query_result = $wpdb->get_results( $prepared ); // all custom fields from postmeta created on base of this ACF subfield
				$handled_fields = array();
				if ( is_array( $query_result ) && !empty( $query_result ) ) {
					foreach ( $query_result as $custom_field ) {
						if ( !in_array( $custom_field->meta_key, $handled_fields ) ) {
							$handled_fields[] = $custom_field->meta_key;
							if ( substr( $custom_field->meta_key, 0, 1 ) !== "_" ) { // this is not a field with name starting with _
								$acf_field_object = get_field_object( $custom_field->meta_key, $custom_field->post_id );
								if ( $acf_field_object ) { // this is valid ACF field
									foreach ( $this->tm_setting_index as $setting_index ) {
										$this->translation_management->settings[ $setting_index ][ $custom_field->meta_key ] = $field['wpml_cf_preferences'];
									}
									if ( (int) $field['wpml_cf_preferences'] !== WPML_IGNORE_CUSTOM_FIELD ) {
										$this->update_corresponding_system_field_settings( $custom_field->meta_key );
									}
								}
							}
						}
					}
				}
			}
		}
	}

	/**
	 * Find corresponding system fields and update theit translation preferences to "Copy".
	 *
	 * Correspoidng system fields' names starts with underscore. They always should be set to copy.
	 *
	 * @param string $field_name Current field name.
	 */
	private function update_corresponding_system_field_settings( $field_name ) {
		$corresponding_field_name = "_" . $field_name;
		foreach ( $this->tm_setting_index as $setting_index ) {
			if ( empty( $this->translation_management->settings[ $setting_index ][ $corresponding_field_name ] ) ) {
				$this->translation_management->settings[ $setting_index ][ $corresponding_field_name ] = WPML_COPY_CUSTOM_FIELD;
			}
		}

	}

	/**
	 * Adds excalamtion mark with title to the field which translation preferences hasn't been set yet.
	 *
	 * @param string $label ACF field's label.
	 * @param array  $field ACF field's metadata.
	 *
	 * @return string Field's label updated with exclamation mark.
	 */
	public function mark_not_migrated_field( $label, $field ) {
		if ( ! isset( $field['wpml_cf_preferences'] ) && $field['ID'] > 0 && $this->isFieldGroupEditScreen() ) {
			$post_exist = $this->get_post_with_custom_field( $field['name'] );
			if ( $post_exist ) {
				$label .= ' <span class="dashicons dashicons-warning acfml-not-migrated"
 							title="' . __("Please review WPML translation preferences for this field before saving field group! Otherwise, default value (Don't translate) will be set.", "acfml") . '"></span>';
			}
		}

		return $label;
	}

	/**
	 * Repeater and flexible fields' translation preferences should be set to Copy.
	 *
	 * Advice to set translation preferences to Copy for repeater and flexible fields
	 * if not already set.
	 *
	 * @param string $label
	 * @param array  $field
	 *
	 * @return string
	 */
	public function adviceToSetCopyForField( $label, $field ) {
		$fieldNotSetToCopy = ! isset( $field['wpml_cf_preferences'] ) || WPML_COPY_CUSTOM_FIELD !== (int) $field['wpml_cf_preferences'];
		if ( $this->field_should_be_set_to_copy( $field ) && $fieldNotSetToCopy && $this->isFieldGroupEditScreen() ) {
			$label .= ' <span class="dashicons dashicons-lightbulb acfml-advice-copy-setting"
 							title="' . esc_attr_x( 'We recommend using the "Copy" translation preferences for repeater and flexible fields. You can use other translation preferences, but if you notice any translation issues with subfields, please go back here and try to change this setting.', 'acfml' ) . '"></span>';
		}
		return $label;
	}

	/**
	 * Checks if it is currently displayed ACF Field Group edit screen.
	 *
	 * @return bool
	 */
	private function isFieldGroupEditScreen() {
		global $post_type, $editing;
		return 'acf-field-group' === $post_type && true === $editing;
	}

	/**
	 * Check if fields type is among fields which always chouls be set to copy.
	 *
	 * @param array $field ACF field data.
	 *
	 * @return bool
	 */
	public function field_should_be_set_to_copy( $field ) {
		$fields_always_copied = [
			'repeater',
			'flexible_content',
		];
		return isset( $field['type'] ) && in_array( $field['type'], $fields_always_copied, true );
	}
}