<?php
/**
 * Customer input cleaning.
 *
 * @package HostKhata
 */

namespace HostKhata\Domain\Customers;

defined( 'ABSPATH' ) || exit;

use HostKhata\Security\Sanitizer;
use HostKhata\Security\Validator;

/**
 * Sanitises and validates customer data coming from forms or the REST API.
 *
 * When creating, every field is cleaned and `first_name` and `email` are
 * required. When updating, only the fields present in the input are cleaned,
 * so a partial update never blanks other fields.
 *
 * @since 0.1.0
 */
final class CustomerInput {

	/**
	 * Text fields and their maximum length.
	 */
	const TEXT_FIELDS = array(
		'first_name' => 100,
		'last_name'  => 100,
		'company'    => 190,
		'phone'      => 40,
		'address_1'  => 190,
		'address_2'  => 190,
		'city'       => 100,
		'state'      => 100,
		'postcode'   => 20,
	);

	/**
	 * Cleans input.
	 *
	 * @since 0.1.0
	 *
	 * @param array<string, mixed> $raw      Unslashed input.
	 * @param bool                 $creating True when a new customer is being created.
	 * @return array{data: array<string, mixed>, errors: array<string, string>}
	 */
	public static function clean( array $raw, bool $creating ): array {
		$data = array();

		foreach ( self::TEXT_FIELDS as $field => $max ) {
			if ( $creating || array_key_exists( $field, $raw ) ) {
				$data[ $field ] = Sanitizer::text( $raw[ $field ] ?? '' );
			}
		}

		if ( $creating || array_key_exists( 'email', $raw ) ) {
			$data['email'] = Sanitizer::email( $raw['email'] ?? '' );
		}

		if ( $creating || array_key_exists( 'country', $raw ) ) {
			$country         = strtoupper( Sanitizer::text( $raw['country'] ?? '' ) );
			$data['country'] = 1 === preg_match( '/^[A-Z]{2}$/', $country ) ? $country : '';
		}

		$status_error = '';

		if ( $creating || array_key_exists( 'status', $raw ) ) {
			$status = Sanitizer::pick( $raw, 'status', CustomerStatus::editable(), $creating ? CustomerStatus::ACTIVE : null );

			if ( null === $status ) {
				$status_error = __( 'Choose one of the allowed values.', 'hostkhata' );
			} else {
				$data['status'] = $status;
			}
		}

		if ( $creating || array_key_exists( 'tags', $raw ) ) {
			$data['tags'] = Tags::parse( $raw['tags'] ?? array() );
		}

		if ( $creating || array_key_exists( 'reminders_muted', $raw ) ) {
			$data['reminders_muted'] = Sanitizer::boolean( $raw['reminders_muted'] ?? false );
		}

		$errors = self::validate( $data, $raw, $creating );

		if ( '' !== $status_error ) {
			$errors['status'] = $status_error;
		}

		return array(
			'data'   => $data,
			'errors' => $errors,
		);
	}

	/**
	 * Validates the cleaned data.
	 *
	 * @param array<string, mixed> $data     Cleaned data.
	 * @param array<string, mixed> $raw      Original input.
	 * @param bool                 $creating Creating or updating.
	 * @return array<string, string>
	 */
	private static function validate( array $data, array $raw, bool $creating ): array {
		$rules = array();

		foreach ( self::TEXT_FIELDS as $field => $max ) {
			if ( isset( $data[ $field ] ) ) {
				$rules[ $field ] = 'max_length:' . $max;
			}
		}

		if ( $creating ) {
			$rules['first_name'] = 'required|' . ( $rules['first_name'] ?? 'max_length:100' );
			$rules['email']      = 'required|email|max_length:190';
		} elseif ( isset( $data['first_name'] ) ) {
			$rules['first_name'] = 'required|max_length:100';
		}

		if ( ! $creating && array_key_exists( 'email', $data ) ) {
			$rules['email'] = 'required|email|max_length:190';
		}

		$errors = ( new Validator() )->validate( $data, $rules )->first_per_field();

		// An email that was sent but cleaned away entirely is invalid, not "missing".
		$email_sent = isset( $raw['email'] ) && is_scalar( $raw['email'] ) && '' !== trim( (string) $raw['email'] );

		if ( $email_sent && array_key_exists( 'email', $data ) && '' === $data['email'] ) {
			$errors['email'] = __( 'Enter a valid email address.', 'hostkhata' );
		}

		if ( isset( $raw['country'] ) && is_scalar( $raw['country'] ) && '' !== trim( (string) $raw['country'] ) && '' === ( $data['country'] ?? '' ) ) {
			$errors['country'] = __( 'Use a two-letter country code, for example BD.', 'hostkhata' );
		}

		return $errors;
	}
}