<?php
/**
 * The WooCommerce shipping method: added to shipping zones, with its own
 * settings per zone (services, free shipping, fallback, options) and one set
 * of store-wide settings (connection, account, parcels).
 *
 * calculate_shipping() turns the package into parcels, asks Canada Post (or
 * the cache) through the Rater, and adds one rate per service. When Canada
 * Post cannot be asked, the failure is logged and counted for the admin
 * notice, and the zone's fallback rate is offered instead, so the customer
 * can still check out.
 */

declare(strict_types=1);

namespace BlueBrainMedia\MapleParcel\Shipping;

use BlueBrainMedia\MapleParcel\Api\ApiException;
use BlueBrainMedia\MapleParcel\Api\Client;
use BlueBrainMedia\MapleParcel\Api\Quote;
use BlueBrainMedia\MapleParcel\Api\RatingClient;
use BlueBrainMedia\MapleParcel\Api\TokenProvider;
use BlueBrainMedia\MapleParcel\Settings\CustomFields;
use BlueBrainMedia\MapleParcel\Settings\Fields;
use BlueBrainMedia\MapleParcel\Settings\Settings;
use BlueBrainMedia\MapleParcel\Support\Health;
use BlueBrainMedia\MapleParcel\Support\Logger;

defined( 'ABSPATH' ) || exit;

class Method extends \WC_Shipping_Method {

	use CustomFields;

	public const ID = 'bbmmp_canada_post';

	/** Hidden rate meta (leading underscore) naming the service, for labels later. */
	public const META_SERVICE = '_bbmmp_service';

	/**
	 * @param int $instance_id The shipping zone method instance, or 0 for the store-wide settings.
	 */
	public function __construct( $instance_id = 0 ) {
		parent::__construct( $instance_id );

		$this->id                 = self::ID;
		$this->method_title       = __( 'Canada Post (Maple Parcel)', 'maple-parcel' );
		$this->method_description = __( 'Live Canada Post rates at checkout, using your own app from Canada Post\'s Developer Portal.', 'maple-parcel' );
		$this->supports           = array( 'shipping-zones', 'instance-settings', 'instance-settings-modal', 'settings' );

		$this->form_fields          = Fields::global();
		$this->instance_form_fields = Fields::instance();
		$this->init_settings();

		$this->title      = (string) $this->get_option( 'title', $this->method_title );
		$this->tax_status = (string) $this->get_option( 'tax_status', 'taxable' );

		add_action( 'woocommerce_update_options_shipping_' . $this->id, array( $this, 'saveSettings' ) );
	}

	/**
	 * The settings page, then bbmmp_settings_after_form on the store-wide page
	 * only (not a zone's modal). The free build's "What Pro adds" panel uses it.
	 */
	public function admin_options(): void {
		parent::admin_options();

		if ( 0 === (int) $this->instance_id ) {
			do_action( 'bbmmp_settings_after_form' );
		}
	}

	/** Saves the store-wide form. process_admin_options() returns a bool an action has no use for. */
	public function saveSettings(): void {
		$this->process_admin_options();
	}

	/**
	 * Keeps the ship-from postal code in one tidy form, and refuses one that
	 * is not Canadian rather than saving something every quote would fail on.
	 */
	public function validate_origin_postal_code_field( string $key, mixed $value ): string {
		$raw = is_string( $value ) ? trim( stripslashes( $value ) ) : '';

		if ( '' === $raw ) {
			return '';
		}

		$postcode = Destination::canadianPostcode( $raw );

		if ( null === $postcode ) {
			\WC_Admin_Settings::add_error( __( 'The ship-from postal code was not saved: it should look like V2S 6X1.', 'maple-parcel' ) );

			return (string) $this->get_option( $key );
		}

		return substr( $postcode, 0, 3 ) . ' ' . substr( $postcode, 3 );
	}

	/** Digits only, at most ten, as Canada Post requires. */
	public function validate_customer_number_field( string $key, mixed $value ): string {
		$number = is_string( $value ) ? (string) preg_replace( '/\D/', '', $value ) : '';

		if ( strlen( $number ) > 10 ) {
			\WC_Admin_Settings::add_error( __( 'The customer number was not saved: it is at most 10 digits.', 'maple-parcel' ) );

			return (string) $this->get_option( $key );
		}

		return $number;
	}

	/**
	 * Offers one rate per service. Canada Post failures never reach the
	 * cart: they are logged, counted, and replaced by the fallback rate.
	 *
	 * @param array<mixed> $package
	 * @throws ApiException Never escapes: thrown for a missing origin and caught below.
	 */
	public function calculate_shipping( $package = array() ): void {
		$settings    = Settings::load();
		$logger      = new Logger( $settings->debug() );
		$destination = Destination::fromPackage( is_array( $package['destination'] ?? null ) ? $package['destination'] : array() );

		if ( null === $destination ) {
			return;
		}

		$choices = Services::choices( $this->get_option( 'services' ) );
		/**
		 * The service codes to ask Canada Post for in this package. Return an
		 * empty array to offer no Canada Post rates, and no fallback rate.
		 *
		 * @param list<string> $services Codes the zone offers for this address.
		 * @param array        $package The WooCommerce package.
		 * @param Method       $method
		 */
		$services = apply_filters( 'bbmmp_services', Services::enabledFor( $destination->group, $choices ), $package, $this );
		$services = is_array( $services ) ? array_values( array_filter( $services, 'is_string' ) ) : array();

		if ( array() === $services ) {
			return;
		}

		$builder = new ParcelBuilder( $settings->packing(), $settings->defaultWeight(), $settings->defaultSides() );

		/**
		 * The parcels to rate for this package. Return an empty array to offer
		 * no Canada Post rates.
		 *
		 * @param list<Parcel> $parcels
		 * @param array        $package The WooCommerce package.
		 * @param Method       $method
		 */
		$parcels = apply_filters( 'bbmmp_parcels', $builder->build( is_array( $package['contents'] ?? null ) ? $package['contents'] : array() ), $package, $this );

		if ( ! is_array( $parcels ) || array() === $parcels ) {
			return;
		}

		foreach ( $parcels as $parcel ) {
			if ( ! $parcel instanceof Parcel ) {
				return;
			}

			if ( $parcel->exceedsLimits() ) {
				$logger->error( sprintf( 'No Canada Post rates: a %s kg parcel of %s x %s x %s cm is over Canada Post\'s limits (30 kg, 200 cm a side, 300 cm length plus girth).', $parcel->weight, $parcel->length, $parcel->width, $parcel->height ) );
				return;
			}
		}

		try {
			if ( '' === $settings->originPostalCode() ) {
				throw new ApiException( __( 'The ship-from postal code is missing. Add it in WooCommerce > Settings > Shipping > Canada Post (Maple Parcel).', 'maple-parcel' ) );
			}

			$quotes = $this->rater( $settings, $logger )->rate( $destination, array_values( $parcels ), $services, 'yes' === $this->get_option( 'coverage' ), 'yes' === $this->get_option( 'signature' ) );
		} catch ( ApiException $e ) {
			$logger->error( 'Canada Post rates failed: ' . $e->getMessage() );
			Health::recordFailure( $e->getMessage() );
			$this->addFallback( $package );
			return;
		}

		Health::recordSuccess();
		Health::noteFirstRate();

		foreach ( $this->rateArgs( $quotes, $services, $choices, $settings->taxMode(), $package ) as $args ) {
			$this->add_rate( $args );

			$rate = $this->rates[ $args['id'] ] ?? null;

			if ( $rate instanceof \WC_Shipping_Rate && '' !== $args['delivery_time'] ) {
				$rate->set_delivery_time( $args['delivery_time'] );
			}
		}
	}

	/**
	 * The add_rate() arguments for each quote, cheapest first, with free
	 * shipping applied and the delivery estimate attached.
	 *
	 * @param list<Quote>                                       $quotes
	 * @param list<string>                                      $services Codes the zone offers here.
	 * @param array<string, array{enabled: bool, name: string}> $choices
	 * @param array<mixed>                                      $package
	 * @return list<array<string, mixed>>
	 */
	public function rateArgs( array $quotes, array $services, array $choices, string $taxMode, array $package ): array {
		$quotes = array_values( array_filter( $quotes, static fn ( Quote $quote ): bool => in_array( $quote->serviceCode, $services, true ) ) );
		usort( $quotes, static fn ( Quote $a, Quote $b ): int => $a->price( $taxMode ) <=> $b->price( $taxMode ) );

		$minimum = (string) $this->get_option( 'free_shipping_min' );
		$free    = is_numeric( $minimum ) && (float) ( $package['contents_cost'] ?? 0 ) >= (float) $minimum;
		$show    = 'yes' === $this->get_option( 'delivery_time', 'yes' );
		$rates   = array();

		foreach ( $quotes as $i => $quote ) {
			$rates[] = array(
				'id'            => $this->get_rate_id( $quote->serviceCode ),
				'label'         => Services::label( $quote->serviceCode, $quote->serviceName, $choices ),
				'cost'          => $free && 0 === $i ? 0 : round( $quote->price( $taxMode ), 2 ),
				// Canada Post's tax-included price already carries the tax.
				'taxes'         => 'due' === $taxMode ? false : '',
				'package'       => $package,
				'meta_data'     => array( self::META_SERVICE => $quote->serviceCode ),
				'delivery_time' => $show ? self::deliveryText( $quote ) : '',
			);
		}

		/**
		 * The rates about to be offered, as add_rate() arguments.
		 *
		 * @param list<array<string, mixed>> $rates
		 * @param list<Quote>                $quotes
		 * @param array                      $package
		 * @param Method                     $method
		 */
		$rates = apply_filters( 'bbmmp_rates', $rates, $quotes, $package, $this );

		return is_array( $rates ) ? array_values( $rates ) : array();
	}

	/**
	 * "Estimated delivery Oct 14", or "Delivered in 3 business days", or ''.
	 *
	 * A date before today is ignored (risk 11: the Test app sends a fixed
	 * 2025 date), so the customer sees the business days instead.
	 */
	public static function deliveryText( Quote $quote ): string {
		if ( null !== $quote->deliveryDate ) {
			$date  = \DateTimeImmutable::createFromFormat( '!Y-m-d', $quote->deliveryDate, wp_timezone() );
			$today = ( new \DateTimeImmutable( 'now', wp_timezone() ) )->setTime( 0, 0 );

			if ( false !== $date && $date >= $today ) {
				/* translators: %s: a date, e.g. Oct 14. */
				return sprintf( __( 'Estimated delivery %s', 'maple-parcel' ), wp_date( _x( 'M j', 'delivery estimate date format', 'maple-parcel' ), $date->getTimestamp() + 12 * HOUR_IN_SECONDS ) );
			}
		}

		if ( null !== $quote->transitDays && $quote->transitDays > 0 ) {
			/* translators: %d: number of business days. */
			return sprintf( _n( 'Delivered in %d business day', 'Delivered in %d business days', $quote->transitDays, 'maple-parcel' ), $quote->transitDays );
		}

		return '';
	}

	/**
	 * Shows the delivery estimate under our rates in the classic cart and
	 * checkout. The Cart and Checkout blocks read it from the rate on their own.
	 */
	public static function showDeliveryTime( mixed $rate ): void {
		if ( ! $rate instanceof \WC_Shipping_Rate || self::ID !== $rate->get_method_id() ) {
			return;
		}

		$text = (string) $rate->get_delivery_time();

		if ( '' !== $text ) {
			printf( '<br /><small class="bbmmp-delivery-time">%s</small>', esc_html( $text ) );
		}
	}

	/** @param array<mixed> $package */
	private function addFallback( array $package ): void {
		$cost = (string) $this->get_option( 'fallback_cost' );

		if ( ! is_numeric( $cost ) ) {
			return;
		}

		$label = trim( (string) $this->get_option( 'fallback_label' ) );

		$this->add_rate(
			array(
				'id'      => $this->get_rate_id( 'fallback' ),
				'label'   => '' !== $label ? $label : __( 'Shipping', 'maple-parcel' ),
				'cost'    => (float) $cost,
				'package' => $package,
			)
		);
	}

	private function rater( Settings $settings, Logger $logger ): Rater {
		$credentials = $settings->credentials();
		$tokens      = new TokenProvider( $credentials, $logger );
		$client      = new RatingClient( new Client( $tokens, $logger, $settings->language() ) );

		// Service names come back in the request's language, so it is part of the key.
		return new Rater( $client, new RateCache( $settings->cacheMinutes(), $credentials->fingerprint() . '|' . $settings->language() ), $settings );
	}
}