<?php
/**
 * Gravity Forms adapter.
 *
 * @package PluginBrewery\AdClickTracking
 */

namespace PluginBrewery\AdClickTracking\Adapters;

use PluginBrewery\AdClickTracking\Constants;
use PluginBrewery\AdClickTracking\Plugin;
use PluginBrewery\AdClickTracking\Upsell;

defined( 'ABSPATH' ) || exit;

/**
 * Injects hidden tracking fields into Gravity Forms so captured ad-click values
 * are stored automatically on every entry.
 */
class Gravity_Forms_Adapter implements Form_Adapter {

	/**
	 * Returns the platform identifier.
	 */
	public function platform_slug(): string {
		return 'gravity-forms';
	}

	/**
	 * Whether Gravity Forms is active and the paid referral tracker is not.
	 *
	 * The full Referral Source Tracking plugin already captures Google Ads data,
	 * so we stand down for this platform to avoid injecting duplicate fields.
	 */
	public function is_available(): bool {
		if ( ! class_exists( '\GFForms' ) ) {
			return false;
		}
		return ! Plugin::is_plugin_active_safe( 'pb-gforms-referral-tracking/pb-gforms-referral-tracking.php' );
	}

	/**
	 * Binds the Gravity Forms hooks.
	 */
	public function register_hooks(): void {
		add_filter( 'gform_form_post_get_meta', array( $this, 'inject_fields' ), 10 );
		add_filter( 'gform_form_settings_fields', array( $this, 'register_form_setting' ), 10, 2 );
		add_filter( 'gform_pre_submission_filter', array( $this, 'ensure_defaults_on_submit' ), 10 );
	}

	/**
	 * Adds hidden tracking fields to the form before it renders.
	 *
	 * @param array $form Form data.
	 * @return array
	 */
	public function inject_fields( $form ) {
		if ( ! is_array( $form ) ) {
			return $form;
		}

		if ( is_admin() && ! $this->is_safe_admin_context() ) {
			return $form;
		}

		if ( ! $this->is_tracking_enabled( $form ) ) {
			return $form;
		}

		// Idempotency guard: if the tracking fields are already present (e.g. an
		// external update_form() persisted them), do not inject a second copy.
		$existing_fields = isset( $form['fields'] ) && is_array( $form['fields'] ) ? $form['fields'] : array();
		foreach ( $existing_fields as $existing ) {
			// phpcs:ignore WordPress.NamingConventions.ValidVariableName.UsedPropertyNotSnakeCase -- cssClass is Gravity Forms' own field property name.
			$css = is_object( $existing ) ? (string) $existing->cssClass : (string) ( $existing['cssClass'] ?? '' );
			if ( false !== strpos( $css, Constants::FIELD_CSS_PREFIX ) ) {
				return $form;
			}
		}

		$constants = Constants::get_instance();
		$base      = $constants->get_base_gfield_id();
		$prefix    = Constants::FIELD_CSS_PREFIX;

		$definitions = array(
			array(
				'id'       => $base . $constants->get_gfield_id( 'source' ),
				'label'    => esc_html__( 'Ad Source', 'ad-click-tracking-for-gravity-forms' ),
				'cssClass' => $prefix . 'source',
			),
			array(
				'id'       => $base . $constants->get_gfield_id( 'network' ),
				'label'    => esc_html__( 'Ad Network', 'ad-click-tracking-for-gravity-forms' ),
				'cssClass' => $prefix . 'network',
			),
			array(
				'id'       => $base . $constants->get_gfield_id( 'clid' ),
				'label'    => esc_html__( 'Ad Click ID', 'ad-click-tracking-for-gravity-forms' ),
				'cssClass' => $prefix . 'clid',
			),
		);

		foreach ( $definitions as $definition ) {
			if ( class_exists( '\GF_Field_Hidden' ) ) {
				$form['fields'][] = new \GF_Field_Hidden( $definition );
			} else {
				$definition['visibility'] = 'hidden';
				$form['fields'][]         = new \GF_Field_Text( $definition );
			}
		}

		return $form;
	}

	/**
	 * Adds the per-form enable toggle to the Gravity Forms form settings.
	 *
	 * @param array $fields Existing settings fields.
	 * @param array $form   Current form.
	 * @return array
	 */
	public function register_form_setting( $fields, $form ) {
		if ( ! isset( $fields['form_options']['fields'] ) || ! is_array( $fields['form_options']['fields'] ) ) {
			return $fields;
		}

		$label   = esc_html__( 'Enable ad click tracking', 'ad-click-tracking-for-gravity-forms' );
		$tooltip = esc_html__( 'Capture Google, Microsoft and Meta ad click IDs on this form.', 'ad-click-tracking-for-gravity-forms' );

		$fields['form_options']['fields'][] = array(
			'name'          => Constants::ENABLE_SETTING_KEY,
			'type'          => 'toggle',
			'label'         => $label,
			'default_value' => (int) get_option( Constants::DEFAULT_ENABLED_OPTION, 0 ),
			'tooltip'       => '<button onclick="return false;" onkeypress="return false;" class="gf_tooltip tooltip tooltip_form_animation" aria-label="&lt;strong&gt;' . $label . '&lt;/strong&gt;' . $tooltip . '"><i class="gform-icon gform-icon--question-mark" aria-hidden="true"></i></button>',
		);

		$fields['form_options']['fields'][] = array(
			'name' => 'pb_act_upgrade_note',
			'type' => 'html',
			'html' => Upsell::note( 'gf-form-settings' ),
		);

		return $fields;
	}

	/**
	 * Fills the Source default when a submission arrives with an empty field.
	 *
	 * @param array $form Form data.
	 * @return array
	 */
	public function ensure_defaults_on_submit( $form ) {
		$constants = Constants::get_instance();
		$source_id = $constants->get_base_gfield_id() . $constants->get_gfield_id( 'source' );
		$field_key = 'input_' . $source_id;

		// phpcs:ignore WordPress.Security.NonceVerification.Missing, WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Gravity Forms' own submission payload; the value is only compared for emptiness, never stored.
		if ( isset( $_POST[ $field_key ] ) && '' === trim( (string) wp_unslash( $_POST[ $field_key ] ) ) ) {
			$_POST[ $field_key ] = 'Unknown';
		}

		return $form;
	}

	/**
	 * Whether tracking is enabled for the form (per-form value or global default).
	 *
	 * @param array $form Form data.
	 */
	private function is_tracking_enabled( array $form ): bool {
		if ( isset( $form[ Constants::ENABLE_SETTING_KEY ] ) ) {
			return 1 === (int) $form[ Constants::ENABLE_SETTING_KEY ];
		}
		return 1 === (int) get_option( Constants::DEFAULT_ENABLED_OPTION, 0 );
	}

	/**
	 * Restricts admin-side field injection to the read-only entry detail view.
	 *
	 * Injecting on the entry edit screen would let Gravity Forms overwrite saved
	 * tracking data with empty values when an admin saves the entry.
	 */
	private function is_safe_admin_context(): bool {
		if ( class_exists( '\GFCommon' ) ) {
			$is_entry_detail      = \GFCommon::is_entry_detail();
			$is_entry_detail_edit = method_exists( '\GFCommon', 'is_entry_detail_edit' ) && \GFCommon::is_entry_detail_edit();
			if ( ! $is_entry_detail || $is_entry_detail_edit ) {
				return false;
			}
		}

		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only admin screen detection.
		if ( isset( $_GET['page'] ) && 'gf_edit_forms' === sanitize_text_field( wp_unslash( $_GET['page'] ) ) ) {
			return false;
		}

		if ( function_exists( 'get_current_screen' ) ) {
			$screen = get_current_screen();
			if ( $screen && in_array( $screen->base, array( 'post', 'site-editor' ), true ) ) {
				return false;
			}
		}

		return true;
	}
}