<?php
/**
 * Emails sent when things happen.
 *
 * @package HostKhata
 */

namespace HostKhata\Domain\Email;

defined( 'ABSPATH' ) || exit;

use HostKhata\Core\Hookable;
use HostKhata\Database\Repositories\CustomerRepository;
use HostKhata\Database\Repositories\InvoiceRepository;
use HostKhata\Database\Repositories\OrderRepository;
use HostKhata\Database\Repositories\PaymentRepository;
use HostKhata\Domain\Customers\CustomerStatus;
use Throwable;

/**
 * Listens to HostKhata's own actions and queues the matching emails.
 *
 * A problem while queueing an email must never break the order, invoice or
 * payment that caused it, so every handler swallows its errors.
 *
 * @since 0.1.0
 */
final class EmailEvents implements Hookable {

	/**
	 * Mailer.
	 *
	 * @var Mailer
	 */
	private $mailer;

	/**
	 * Merge tag values.
	 *
	 * @var EmailVars
	 */
	private $vars;

	/**
	 * Customers.
	 *
	 * @var CustomerRepository
	 */
	private $customers;

	/**
	 * Orders.
	 *
	 * @var OrderRepository
	 */
	private $orders;

	/**
	 * Invoices.
	 *
	 * @var InvoiceRepository
	 */
	private $invoices;

	/**
	 * Payments.
	 *
	 * @var PaymentRepository
	 */
	private $payments;

	/**
	 * Constructor.
	 *
	 * @param Mailer             $mailer    Mailer.
	 * @param EmailVars          $vars      Merge tag values.
	 * @param CustomerRepository $customers Customers.
	 * @param OrderRepository    $orders    Orders.
	 * @param InvoiceRepository  $invoices  Invoices.
	 * @param PaymentRepository  $payments  Payments.
	 */
	public function __construct( Mailer $mailer, EmailVars $vars, CustomerRepository $customers, OrderRepository $orders, InvoiceRepository $invoices, PaymentRepository $payments ) {
		$this->mailer    = $mailer;
		$this->vars      = $vars;
		$this->customers = $customers;
		$this->orders    = $orders;
		$this->invoices  = $invoices;
		$this->payments  = $payments;
	}

	/**
	 * {@inheritdoc}
	 */
	public function register(): void {
		add_action( 'hostkhata_order_placed', array( $this, 'on_order_placed' ), 10, 1 );
		add_action( 'hostkhata_order_fulfilled', array( $this, 'on_order_fulfilled' ), 10, 1 );
		add_action( 'hostkhata_invoice_issued', array( $this, 'on_invoice_issued' ), 10, 1 );
		add_action( 'hostkhata_payment_recorded', array( $this, 'on_payment_recorded' ), 10, 2 );
		add_action( 'hostkhata_payment_refunded', array( $this, 'on_payment_refunded' ), 10, 2 );
		add_action( 'hostkhata_customer_created', array( $this, 'on_customer_created' ), 10, 1 );
		add_action( 'hostkhata_customer_status_changed', array( $this, 'on_customer_status_changed' ), 10, 3 );
		add_action( 'hostkhata_payment_claimed', array( $this, 'on_payment_claimed' ), 10, 2 );
		add_action( 'hostkhata_payment_rejected', array( $this, 'on_payment_rejected' ), 10, 3 );
		add_action( 'hostkhata_customer_request', array( $this, 'on_customer_request' ), 10, 3 );
	}

	/**
	 * Order received: tell the customer and the admin.
	 *
	 * @since 0.1.0
	 *
	 * @param int $order_id Order id.
	 * @return void
	 */
	public function on_order_placed( $order_id ): void {
		$this->guard(
			function () use ( $order_id ) {
				$order = $this->orders->find( (int) $order_id );

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

				$customer = $this->customers->find( $order['customer_id'] );
				$vars     = array_merge( $this->vars->base( $customer ), $this->vars->order( $order ) );

				$this->to_customer( 'order_received', $customer, $vars, 'order', $order['id'] );
				$this->mailer->queue_to_admin( 'admin_new_order', $vars, 'order', $order['id'] );
			}
		);
	}

	/**
	 * Order fulfilled: tell the customer their account is ready.
	 *
	 * @since 0.1.0
	 *
	 * @param int $order_id Order id.
	 * @return void
	 */
	public function on_order_fulfilled( $order_id ): void {
		$this->guard(
			function () use ( $order_id ) {
				$order = $this->orders->find( (int) $order_id );

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

				$customer = $this->customers->find( $order['customer_id'] );
				$vars     = array_merge( $this->vars->base( $customer ), $this->vars->order( $order ), $this->vars->order_details( $order['id'] ) );

				$this->to_customer( 'account_ready', $customer, $vars, 'order', $order['id'] );
			}
		);
	}

	/**
	 * Invoice issued: send it to the customer.
	 *
	 * @since 0.1.0
	 *
	 * @param int $invoice_id Invoice id.
	 * @return void
	 */
	public function on_invoice_issued( $invoice_id ): void {
		$this->guard(
			function () use ( $invoice_id ) {
				$invoice = $this->invoices->find( (int) $invoice_id );

				// An invoice with nothing to pay needs no email.
				if ( null === $invoice || $invoice['total'] <= 0 ) {
					return;
				}

				$customer = $this->customers->find( $invoice['customer_id'] );

				$this->to_customer( 'invoice_issued', $customer, array_merge( $this->vars->base( $customer ), $this->vars->invoice( $invoice ) ), 'invoice', $invoice['id'] );
			}
		);
	}

	/**
	 * Payment recorded: send a receipt.
	 *
	 * @since 0.1.0
	 *
	 * @param int $payment_id Payment id.
	 * @param int $invoice_id Invoice id.
	 * @return void
	 */
	public function on_payment_recorded( $payment_id, $invoice_id = 0 ): void {
		$this->payment_email( 'payment_received', (int) $payment_id, (int) $invoice_id );
	}

	/**
	 * Refund recorded: tell the customer.
	 *
	 * @since 0.1.0
	 *
	 * @param int $refund_id  Refund row id.
	 * @param int $invoice_id Invoice id.
	 * @return void
	 */
	public function on_payment_refunded( $refund_id, $invoice_id = 0 ): void {
		$this->payment_email( 'payment_refunded', (int) $refund_id, (int) $invoice_id );
	}

	/**
	 * A new customer who can log in right away gets a welcome email.
	 *
	 * @since 0.1.0
	 *
	 * @param int $customer_id Customer id.
	 * @return void
	 */
	public function on_customer_created( $customer_id ): void {
		$this->guard(
			function () use ( $customer_id ) {
				$customer = $this->customers->find( (int) $customer_id );

				/**
				 * Filters whether a new customer gets the welcome email.
				 *
				 * @since 0.1.0
				 *
				 * @param bool $send Whether to send it.
				 */
				if ( $customer && CustomerStatus::ACTIVE === $customer['status'] && apply_filters( 'hostkhata_send_welcome_email', true ) ) {
					$this->to_customer( 'welcome', $customer, $this->vars->base( $customer ), 'customer', $customer['id'] );
				}
			}
		);
	}

	/**
	 * A customer who was waiting for approval and is now active is told so.
	 *
	 * @since 0.1.0
	 *
	 * @param int    $customer_id Customer id.
	 * @param string $from        Old status.
	 * @param string $to          New status.
	 * @return void
	 */
	public function on_customer_status_changed( $customer_id, $from = '', $to = '' ): void {
		if ( CustomerStatus::PENDING !== $from || CustomerStatus::ACTIVE !== $to ) {
			return;
		}

		$this->guard(
			function () use ( $customer_id ) {
				$customer = $this->customers->find( (int) $customer_id );

				if ( $customer ) {
					$this->to_customer( 'account_approved', $customer, $this->vars->base( $customer ), 'customer', $customer['id'] );
				}
			}
		);
	}

	/**
	 * A customer reported a payment: tell the admin to check it.
	 *
	 * @since 0.1.0
	 *
	 * @param int $payment_id Payment id.
	 * @param int $invoice_id Invoice id.
	 * @return void
	 */
	public function on_payment_claimed( $payment_id, $invoice_id = 0 ): void {
		$this->guard(
			function () use ( $payment_id, $invoice_id ) {
				$payment = $this->payments->find( (int) $payment_id );
				$invoice = $this->invoices->find( (int) $invoice_id );

				if ( null === $payment || null === $invoice ) {
					return;
				}

				$customer = $this->customers->find( $invoice['customer_id'] );
				$vars     = array_merge(
					$this->vars->base( $customer ),
					$this->vars->invoice( $invoice ),
					array(
						'payment_amount'    => $this->vars->money( $payment['amount'] ),
						'payment_method'    => $payment['gateway'],
						'payment_reference' => '' !== $payment['transaction_id'] ? $payment['transaction_id'] : $payment['sender_number'],
						'admin_url'         => admin_url( 'admin.php?page=hostkhata#/payments' ),
					)
				);

				$this->mailer->queue_to_admin( 'admin_payment_claim', $vars, 'invoice', $invoice['id'] );
			}
		);
	}

	/**
	 * A reported payment was rejected: tell the customer.
	 *
	 * @since 0.1.0
	 *
	 * @param int    $payment_id Payment id.
	 * @param int    $invoice_id Invoice id.
	 * @param string $reason     Reason given by the admin.
	 * @return void
	 */
	public function on_payment_rejected( $payment_id, $invoice_id = 0, $reason = '' ): void {
		$this->guard(
			function () use ( $payment_id, $invoice_id, $reason ) {
				$payment = $this->payments->find( (int) $payment_id );
				$invoice = $this->invoices->find( (int) $invoice_id );

				if ( null === $payment || null === $invoice ) {
					return;
				}

				$customer = $this->customers->find( $invoice['customer_id'] );
				$vars     = array_merge(
					$this->vars->base( $customer ),
					$this->vars->invoice( $invoice ),
					array(
						'payment_amount' => $this->vars->money( $payment['amount'] ),
						'reason'         => (string) $reason,
					)
				);

				$this->to_customer( 'payment_rejected', $customer, $vars, 'invoice', $invoice['id'] );
			}
		);
	}

	/**
	 * A customer sent a request: tell the admin.
	 *
	 * @since 0.1.0
	 *
	 * @param int    $customer_id Customer id.
	 * @param string $type        Kind of request, as text.
	 * @param string $message     What the customer wrote.
	 * @return void
	 */
	public function on_customer_request( $customer_id, $type = '', $message = '' ): void {
		$this->guard(
			function () use ( $customer_id, $type, $message ) {
				$customer = $this->customers->find( (int) $customer_id );

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

				$vars = array_merge(
					$this->vars->base( $customer ),
					array(
						'request_type'    => (string) $type,
						'request_message' => (string) $message,
						'admin_url'       => admin_url( 'admin.php?page=hostkhata#/customers/' . $customer['id'] ),
					)
				);

				$this->mailer->queue_to_admin( 'admin_customer_request', $vars, 'customer', $customer['id'] );
			}
		);
	}

	/**
	 * Queues a payment or refund email.
	 *
	 * @param string $key        Template key.
	 * @param int    $payment_id Payment row id.
	 * @param int    $invoice_id Invoice id.
	 * @return void
	 */
	private function payment_email( string $key, int $payment_id, int $invoice_id ): void {
		$this->guard(
			function () use ( $key, $payment_id, $invoice_id ) {
				$payment = $this->payments->find( $payment_id );
				$invoice = $this->invoices->find( $invoice_id );

				if ( null === $payment || null === $invoice ) {
					return;
				}

				$customer = $this->customers->find( $invoice['customer_id'] );
				$vars     = array_merge(
					$this->vars->base( $customer ),
					$this->vars->invoice( $invoice ),
					array( 'payment_amount' => $this->vars->money( $payment['amount'] ) )
				);

				$this->to_customer( $key, $customer, $vars, 'invoice', $invoice['id'] );
			}
		);
	}

	/**
	 * Queues an email to a customer, unless they cannot be written to.
	 *
	 * @param string                    $key          Template key.
	 * @param array<string, mixed>|null $customer     Customer row.
	 * @param array<string, string>     $vars         Merge tag values.
	 * @param string                    $related_type Related object type.
	 * @param int                       $related_id   Related object id.
	 * @return void
	 */
	private function to_customer( string $key, ?array $customer, array $vars, string $related_type, int $related_id ): void {
		if ( null === $customer || CustomerStatus::ANONYMISED === $customer['status'] || empty( $customer['user_email'] ) ) {
			return;
		}

		$this->mailer->queue( $key, (string) $customer['user_email'], trim( $customer['first_name'] . ' ' . $customer['last_name'] ), $vars, $related_type, $related_id );
	}

	/**
	 * Runs a handler and swallows any error.
	 *
	 * @param callable $handler Handler.
	 * @return void
	 */
	private function guard( callable $handler ): void {
		try {
			$handler();
		} catch ( Throwable $e ) {
			do_action( 'hostkhata_log', 'error', 'Email event failed: ' . $e->getMessage(), array() ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- Prefixed.
		}
	}
}