<?php
/**
 * WPForms context factory.
 *
 * @package ZeroSpamForms
 */

namespace TwoOTwoCode\ZeroSpamForms\Integrations\WPForms;

defined( 'ABSPATH' ) || exit;

use TwoOTwoCode\ZeroSpamForms\Engine\SubmissionContext;
use TwoOTwoCode\ZeroSpamForms\Integrations\ProtectionFieldRenderer;
use TwoOTwoCode\ZeroSpamForms\Integrations\SubmissionContextFactory;

/**
 * Converts WPForms submission data into engine context.
 */
final class WPFormsContextFactory extends SubmissionContextFactory {
	/**
	 * Default form identifier used when form metadata is unavailable.
	 */
	public const DEFAULT_FORM_ID = 'wpforms';

	/**
	 * Build a form identifier from WPForms form data.
	 *
	 * @param array<string, mixed> $form_data WPForms form data.
	 */
	public function get_form_id( array $form_data ): string {
		if ( isset( $form_data['id'] ) && is_scalar( $form_data['id'] ) && '' !== (string) $form_data['id'] ) {
			return self::DEFAULT_FORM_ID . '-' . (string) $form_data['id'];
		}

		return self::DEFAULT_FORM_ID;
	}

	/**
	 * Build context from WPForms process data.
	 *
	 * @param array<int|string, mixed> $fields                Normalized WPForms fields.
	 * @param array<string, mixed>     $entry                 WPForms entry data.
	 * @param array<string, mixed>     $form_data             WPForms form data.
	 * @param array<string, mixed>     $fallback_posted_data  Fallback posted data.
	 * @param string                   $rate_limit_identifier Identifier used only for hashing.
	 * @param int|null                 $timestamp             Current timestamp.
	 */
	public function build_from_submission(
		array $fields,
		array $entry,
		array $form_data,
		array $fallback_posted_data,
		string $rate_limit_identifier = '',
		?int $timestamp = null
	): SubmissionContext {
		unset( $entry );

		return $this->build_from_submitted_data(
			$this->normalize_submission_data( $fields, $fallback_posted_data ),
			$this->get_form_id( $form_data ),
			$rate_limit_identifier,
			$timestamp
		);
	}

	/**
	 * Normalize WPForms field data and root protection fields.
	 *
	 * @param array<int|string, mixed> $fields               Normalized WPForms fields.
	 * @param array<string, mixed>     $fallback_posted_data Fallback posted data.
	 *
	 * @return array<string, mixed>
	 */
	private function normalize_submission_data( array $fields, array $fallback_posted_data ): array {
		$submitted_data = $this->extract_internal_fields( $fallback_posted_data );

		foreach ( $fields as $field_key => $field ) {
			$key = (string) $field_key;

			if ( is_array( $field ) ) {
				$value = $this->extract_field_value( $field );

				if ( null !== $value ) {
					$submitted_data[ 'field_' . $key ] = $value;
				}

				continue;
			}

			if ( is_scalar( $field ) ) {
				$submitted_data[ 'field_' . $key ] = $field;
			}
		}

		return $submitted_data;
	}

	/**
	 * Extract internal 2o2code Spamless Forms fields from posted data.
	 *
	 * @param array<string, mixed> $posted_data Posted data.
	 *
	 * @return array<string, mixed>
	 */
	private function extract_internal_fields( array $posted_data ): array {
		$internal_fields = array();

		foreach ( $this->get_internal_field_names() as $field_name ) {
			if ( array_key_exists( $field_name, $posted_data ) ) {
				$internal_fields[ $field_name ] = $posted_data[ $field_name ];
			}
		}

		return $internal_fields;
	}

	/**
	 * Extract a scalar field value from WPForms field data.
	 *
	 * @param array<string, mixed> $field Field data.
	 *
	 * @return scalar|null
	 */
	private function extract_field_value( array $field ) {
		foreach ( array( 'value', 'value_raw', 'name' ) as $value_key ) {
			if ( isset( $field[ $value_key ] ) && is_scalar( $field[ $value_key ] ) ) {
				return $field[ $value_key ];
			}
		}

		return null;
	}

	/**
	 * Get internal field names.
	 *
	 * @return array<int, string>
	 */
	private function get_internal_field_names(): array {
		return array(
			ProtectionFieldRenderer::HONEYPOT_FIELD,
			ProtectionFieldRenderer::TOKEN_FIELD,
			ProtectionFieldRenderer::STARTED_AT_FIELD,
		);
	}
}