<?php

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( 'AIEO_Runtime_Payment_Fee_Guard', false ) ) {

	class AIEO_Runtime_Payment_Fee_Guard {

		const OPTION_KEY       = 'aieo_dmm_free_shipping';
		const OPTION_RATES_KEY = 'aieo_dmm_cod_courier_rates';
		const STATS_KEY        = 'aieo_fee_guard_stats';

		
		private static $instance = null;

		
		private $settings_memo = null;

		
		private $seen = array();

		public static function instance() {
			if ( self::$instance === null ) {
				self::$instance = new self();
			}
			return self::$instance;
		}

		private function __construct() {
			
			
			
			
			add_action( 'woocommerce_store_api_checkout_update_order_from_request', array( $this, 'guard_store_api' ), 20, 2 );
			add_action( 'woocommerce_checkout_order_processed', array( $this, 'guard_classic' ), 20, 3 );
			add_action( 'woocommerce_before_pay_action', array( $this, 'guard_order_pay' ), 20, 1 );
		}

		
		
		

		
		public function guard_store_api( $order, $request = null ) {
			
			
			
			
			
			
			
			
			
			
			if ( $request instanceof WP_REST_Request && 'POST' !== strtoupper( (string) $request->get_method() ) ) {
				return;
			}
			$this->reconcile( $order, null, false, 'block checkout' );
		}

		
		public function guard_classic( $order_id, $posted_data = array(), $order = null ) {
			unset( $posted_data );
			if ( ! $order instanceof WC_Order ) {
				$order = wc_get_order( $order_id );
			}
			$this->reconcile( $order, null, true, 'shortcode checkout' );
		}

		
		public function guard_order_pay( $order ) {
			
			$posted = isset( $_POST['payment_method'] ) ? wc_clean( wp_unslash( $_POST['payment_method'] ) ) : '';
			if ( $posted === '' ) {
				return;
			}
			$this->reconcile( $order, (string) $posted, true, 'order-pay retry' );
		}

		
		
		

		
		public function reconcile( $order, $forced_method = null, $persist = false, $context = '' ) {
			if ( ! $order instanceof WC_Order ) {
				return false;
			}

			
			if ( ! apply_filters( 'aieo_payment_fee_guard_enabled', true, $order ) ) {
				return false;
			}

			$order_id = (int) $order->get_id();
			if ( $order_id > 0 && isset( $this->seen[ $order_id ] ) ) {
				return false;
			}

			$s = $this->get_settings();
			if ( $s['cod_enabled'] !== 'yes' ) {
				return false;
			}

			$label = self::cod_label( $s['cod_label'] );
			$slug  = trim( (string) $s['cod_gateway_slug'] );
			if ( $label === '' || $slug === '' ) {
				return false;
			}

			if ( ! $this->is_reconcilable( $order ) ) {
				return false;
			}

			$method  = ( $forced_method !== null ) ? (string) $forced_method : (string) $order->get_payment_method();
			$is_cod  = ( $method === $slug );
			$taxable = ( $s['cod_taxable'] === 'yes' );

			$expected = (float) $s['cod_fee'];
			$override = $this->fee_override_for_order( $order );
			if ( $override !== null ) {
				$expected = (float) $override;
			}

			
			
			$matches = array();
			foreach ( $order->get_items( 'fee' ) as $item_id => $item ) {
				if ( $this->label_matches( $item->get_name(), $label ) ) {
					$matches[ $item_id ] = $item;
				}
			}

			$changed = false;
			$action  = '';
			$before  = 0.0;
			foreach ( $matches as $item ) {
				$before += (float) $item->get_total();
			}

			if ( ! $is_cod || $expected <= 0 ) {
				
				
				
				foreach ( $matches as $item_id => $item ) {
					$order->remove_item( $item_id );
					$changed = true;
				}
				$action = 'removed';
			} else {
				$keep = null;
				foreach ( $matches as $item_id => $item ) {
					if ( $keep === null ) {
						$keep = $item;
						continue;
					}
					$order->remove_item( $item_id );
					$changed = true;
					$action  = 'deduplicated';
				}

				if ( $keep === null ) {
					$fee = new WC_Order_Item_Fee();
					$fee->set_name( $label );
					$fee->set_total( wc_format_decimal( $expected, wc_get_price_decimals() ) );
					$fee->set_tax_status( $taxable ? 'taxable' : 'none' );
					$order->add_item( $fee );
					$changed = true;
					$action  = 'added';
				} elseif ( abs( (float) $keep->get_total() - $expected ) >= 0.005 ) {
					$keep->set_total( wc_format_decimal( $expected, wc_get_price_decimals() ) );
					$keep->set_tax_status( $taxable ? 'taxable' : 'none' );
					$changed = true;
					$action  = 'corrected';
				}
			}

			if ( ! $changed ) {
				return false;
			}

			
			
			
			
			$order->calculate_totals( $taxable );

			if ( $order_id > 0 ) {
				$this->seen[ $order_id ] = true;
				$order->add_order_note(
					sprintf(
						
						__( 'Payment Fee Guard %1$s "%2$s" (%3$s to %4$s). Payment method: %5$s. Context: %6$s.', 'ai-eshop-optimizer' ),
						$action,
						$label,
						wc_format_decimal( $before, wc_get_price_decimals() ),
						wc_format_decimal( $is_cod && $expected > 0 ? $expected : 0, wc_get_price_decimals() ),
						$method,
						$context !== '' ? $context : 'unknown'
					)
				);
			}

			$this->bump_stats( $action, $order_id, $method );

			
			do_action( 'aieo_payment_fee_guard_corrected', $order, $action, $method, $context );

			if ( $persist ) {
				$order->save();
			}

			return true;
		}

		
		
		

		
		private function is_reconcilable( $order ) {
			if ( $order->get_type() !== 'shop_order' ) {
				return false;
			}
			if ( (float) $order->get_total_refunded() > 0 ) {
				return false;
			}
			$closed = array( 'completed', 'cancelled', 'refunded', 'failed' );
			if ( in_array( $order->get_status(), $closed, true ) ) {
				return false;
			}
			return true;
		}

		
		private function label_matches( $candidate, $label ) {
			return mb_strtolower( trim( (string) $candidate ) ) === mb_strtolower( trim( (string) $label ) );
		}

		
		private function fee_override_for_order( $order ) {
			$rates = get_option( self::OPTION_RATES_KEY, array() );
			if ( ! is_array( $rates ) || empty( $rates ) ) {
				return null;
			}
			if ( ! class_exists( 'WC_Shipping_Zones' ) ) {
				return null;
			}

			$map = $this->rate_id_to_carrier_map();
			if ( empty( $map ) ) {
				return null;
			}

			foreach ( $order->get_items( 'shipping' ) as $item ) {
				$method_id   = (string) $item->get_method_id();
				$instance_id = (string) $item->get_instance_id();
				if ( $method_id === '' || $instance_id === '' ) {
					continue;
				}
				$base = $method_id . ':' . $instance_id;
				if ( isset( $map[ $base ] ) && isset( $rates[ $map[ $base ] ] ) ) {
					return (float) $rates[ $map[ $base ] ];
				}
			}

			return null;
		}

		
		private function rate_id_to_carrier_map() {
			static $memo = null;
			if ( $memo !== null ) {
				return $memo;
			}
			$map   = array();
			$zones = WC_Shipping_Zones::get_zones();
			$rest  = WC_Shipping_Zones::get_zone( 0 );
			if ( $rest ) {
				$zones[0] = array( 'shipping_methods' => $rest->get_shipping_methods( false ) );
			}
			foreach ( $zones as $zone ) {
				$methods = isset( $zone['shipping_methods'] ) ? $zone['shipping_methods'] : array();
				foreach ( $methods as $m ) {
					$iid = (int) ( method_exists( $m, 'get_instance_id' ) ? $m->get_instance_id() : 0 );
					if ( $iid <= 0 ) {
						continue;
					}
					$mid   = (string) $m->id;
					$title = method_exists( $m, 'get_title' ) ? (string) $m->get_title() : '';
					if ( $title === '' ) {
						$title = $mid;
					}
					$map[ $mid . ':' . $iid ] = $mid . '|' . trim( $title );
				}
			}
			$memo = $map;
			return $memo;
		}

		
		public static function cod_label( $stored ) {
			$label = trim( (string) $stored );
			if ( '' === $label && did_action( 'init' ) ) {
				$label = __( 'Cash on delivery cost', 'ai-eshop-optimizer' );
			}
			return $label;
		}

		
		private function get_settings() {
			if ( $this->settings_memo !== null ) {
				return $this->settings_memo;
			}
			$stored = get_option( self::OPTION_KEY, array() );
			if ( ! is_array( $stored ) ) {
				$stored = array();
			}
			$legacy = get_option( 'om_fs_settings', array() );
			if ( ! is_array( $legacy ) ) {
				$legacy = array();
			}
			$defaults = array(
				'cod_enabled'      => 'no',
				'cod_gateway_slug' => 'cod',
				'cod_fee'          => 0,
				'cod_label'        => '',
				'cod_taxable'      => 'no',
			);
			$this->settings_memo = array_merge( $defaults, array_merge( $legacy, $stored ) );
			return $this->settings_memo;
		}

		
		private function bump_stats( $action, $order_id = 0, $method = '' ) {
			if ( $action === '' ) {
				return;
			}
			$stats = get_option( self::STATS_KEY, array() );
			if ( ! is_array( $stats ) ) {
				$stats = array();
			}
			$stats[ $action ]  = isset( $stats[ $action ] ) ? ( (int) $stats[ $action ] ) + 1 : 1;
			$stats['total']    = isset( $stats['total'] ) ? ( (int) $stats['total'] ) + 1 : 1;
			$stats['last_gmt'] = gmdate( 'Y-m-d H:i:s' ) . ' UTC';

			if ( (int) $order_id > 0 ) {
				$recent = isset( $stats['recent'] ) && is_array( $stats['recent'] ) ? $stats['recent'] : array();
				array_unshift( $recent, array(
					'order_id' => (int) $order_id,
					'action'   => (string) $action,
					'method'   => (string) $method,
					'gmt'      => gmdate( 'Y-m-d H:i:s' ),
				) );
				$stats['recent'] = array_slice( $recent, 0, 10 );
			}

			update_option( self::STATS_KEY, $stats, false );
		}
	}
}