<?php
/**
 * Sends a report run to its recipients.
 *
 * @package TurtleReport
 */

namespace TurtleReport\Email;

use TurtleReport\Delivery\DeliveryRepository;
use TurtleReport\Delivery\Readiness;
use TurtleReport\Delivery\RunRepository;
use TurtleReport\Policy\Options;
use TurtleReport\Policy\Schedule;
use TurtleReport\Profiles\Profile;

defined( 'ABSPATH' ) || exit;

/**
 * Sends one email per due recipient, claiming each recipient row before it is
 * sent so two processes never email the same person, and records each result.
 * Also holds the fallback used when the delivery history tables are missing.
 */
final class RecipientSender {

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

	/**
	 * Runs.
	 *
	 * @var RunRepository
	 */
	private $runs;

	/**
	 * Per-recipient deliveries.
	 *
	 * @var DeliveryRepository
	 */
	private $deliveries;

	/**
	 * Status log per client.
	 *
	 * @var EmailLog
	 */
	private $log;

	/**
	 * Audience resolver.
	 *
	 * @var Recipients
	 */
	private $recipients;

	/**
	 * Send locks, renewed before each recipient.
	 *
	 * @var SendLocks
	 */
	private $locks;

	/**
	 * Constructor.
	 *
	 * @param ReportMailer       $mailer     Mailer.
	 * @param RunRepository      $runs       Runs.
	 * @param DeliveryRepository $deliveries Deliveries.
	 * @param EmailLog           $log        Status log.
	 * @param Recipients         $recipients Audience resolver.
	 * @param SendLocks          $locks      Send locks.
	 */
	public function __construct( ReportMailer $mailer, RunRepository $runs, DeliveryRepository $deliveries, EmailLog $log, Recipients $recipients, SendLocks $locks ) {
		$this->mailer     = $mailer;
		$this->runs       = $runs;
		$this->deliveries = $deliveries;
		$this->log        = $log;
		$this->recipients = $recipients;
		$this->locks      = $locks;
	}

	/**
	 * Sends a run's email to every recipient that is due.
	 *
	 * @param Profile $site Site.
	 * @param array   $run  Run.
	 * @param int     $now  Unix time.
	 * @return array Run afterwards.
	 */
	public function send_pending( Profile $site, array $run, $now ) {
		$rows    = $this->deliveries->for_run( $run['id'] );
		$due     = array_filter(
			$rows,
			static function ( $r ) use ( $now ) {
				return in_array( $r['status'], array( DeliveryRepository::PENDING, DeliveryRepository::RETRYING ), true ) && $r['next_attempt'] <= $now;
			}
		);
		$message = null;
		$errors  = array();
		try {
			foreach ( $due as $row ) {
				$this->locks->renew_lock( $site->id );
				$claimed = $this->deliveries->claim( $row['id'], $now );
				if ( ! $claimed ) {
					continue; // Another process has it.
				}
				if ( null === $message ) {
					$message = $this->mailer->compose( $site, $run, RunRepository::KIND_TEST === $run['kind'] );
				}
				$this->locks->renew_lock( $site->id );
				$result = $this->mailer->deliver( $message, $row['recipient'] );
				if ( is_wp_error( $result ) ) {
					$data     = $result->get_error_data();
					$errors[] = $result->get_error_message();
					$this->deliveries->record( $row, false, $result->get_error_message(), $now, ! empty( $data['permanent'] ) || RunRepository::KIND_TEST === $run['kind'] ? false : null, $claimed );
				} else {
					$this->deliveries->record( $row, true, '', $now, null, $claimed );
				}
			}
		} finally {
			if ( null !== $message ) {
				$this->mailer->cleanup( $message );
			}
		}
		$meta = (array) $run['meta'];
		if ( $message ) {
			$meta['pdf'] = empty( $site->delivery['attach_pdf'] ) ? 'off' : ( $message['attachments'] ? 'attached' : 'failed' );
			if ( '' !== $message['pdf_error'] ) {
				$meta['pdf_error'] = $message['pdf_error'];
			}
			$meta['link'] = '' !== $message['share_url'];
		}
		$tally  = DeliveryRepository::tally( $this->deliveries->for_run( $run['id'] ) );
		$status = DeliveryRepository::run_status( $tally );
		$this->runs->update(
			$run['id'],
			array(
				'status'  => $status,
				'sent_at' => $tally[ DeliveryRepository::ACCEPTED ] ? ( $run['sent_at'] ? $run['sent_at'] : $now ) : $run['sent_at'],
				'meta'    => $meta,
			)
		);
		if ( RunRepository::KIND_SCHEDULED === $run['kind'] && $message ) {
			$fields = array(
				'last_count' => $tally[ DeliveryRepository::ACCEPTED ],
				'last_error' => $errors ? sprintf(
					/* translators: 1: number of failed recipients, 2: total recipients, 3: error. */
					__( '%1$d of %2$d recipients failed: %3$s', 'turtlereport' ),
					$tally[ DeliveryRepository::FAILED ] + $tally[ DeliveryRepository::RETRYING ],
					array_sum( $tally ),
					$errors[0]
				) : '',
			);
			if ( $tally[ DeliveryRepository::ACCEPTED ] ) {
				$fields['last_sent'] = $now;
			}
			$this->log->update( $site->id, $fields );
		}
		return $this->runs->find( $run['id'] );
	}

	/**
	 * Fallback when the history tables can't be created: sends to everyone once
	 * and records how many were really accepted.
	 *
	 * @param Profile $site Site.
	 * @param int     $now  Unix time.
	 * @param int     $slot Slot.
	 * @return void
	 */
	public function send_without_history( Profile $site, $now, $slot ) {
		$to          = $this->recipients->addresses( $site );
		$period      = Schedule::period( $site->email, wp_date( 'Y-m-d', $slot ) );
		$prep        = $this->mailer->builder()->prepare( $site, $period );
		$run         = ReportMailer::virtual_run( $site, $period, $prep );
		$run['kind'] = RunRepository::KIND_SCHEDULED;
		// Without history there is no review queue or hold to come back to: never send instead.
		if ( Options::MODE_REVIEW === $site->delivery['mode'] ) {
			$this->log->update( $site->id, array( 'last_error' => __( 'Not sent: this report needs review, but the delivery history tables could not be set up. Fix the database setup shown on the Email deliveries screen.', 'turtlereport' ) ) );
			return;
		}
		if ( Readiness::BLOCKED === $prep['readiness']['level'] && Options::INCOMPLETE_HOLD === $site->delivery['incomplete'] ) {
			$this->log->update( $site->id, array( 'last_error' => __( 'Held: the report was incomplete, and the delivery history tables needed to review it could not be set up.', 'turtlereport' ) ) );
			return;
		}
		if ( ! $to ) {
			$this->log->update(
				$site->id,
				array(
					'last_error' => __( 'Nobody to send to: no one can view this site yet and no other people or addresses are chosen.', 'turtlereport' ),
					'last_count' => 0,
				)
			);
			return;
		}
		$message = $this->mailer->compose( $site, $run );
		$ok      = 0;
		$first   = '';
		try {
			foreach ( $to as $address ) {
				$this->locks->renew_lock( $site->id );
				$r = $this->mailer->deliver( $message, $address );
				if ( is_wp_error( $r ) ) {
					$first = '' !== $first ? $first : $r->get_error_message();
				} else {
					++$ok;
				}
			}
		} finally {
			$this->mailer->cleanup( $message );
		}
		$count  = count( $to );
		$fields = array(
			'last_count' => $ok,
			/* translators: 1: failed count, 2: total, 3: error. */
			'last_error' => $ok === $count ? '' : sprintf( __( '%1$d of %2$d recipients failed: %3$s', 'turtlereport' ), $count - $ok, $count, $first ),
		);
		if ( $ok ) {
			$fields['last_sent'] = $now;
		}
		$this->log->update( $site->id, $fields );
	}
}