<?php
/**
 * Emails (plain text, sent with wp_mail()).
 *
 * Every mail can be changed with the `paygrab_mail_{type}` filter
 * ( array( 'subject' => ..., 'body' => ... ) ). PAYGRAB Pro adds an editor for them.
 *
 * @package PAYGRAB
 */

defined( 'ABSPATH' ) || exit;

/**
 * Compose and send PAYGRAB emails.
 */
class Paygrab_Mailer {

	/**
	 * Hooks.
	 *
	 * @return void
	 */
	public static function init() {
		add_action( 'paygrab_order_placed', array( __CLASS__, 'on_placed' ), 10, 2 );
		add_action( 'paygrab_order_status_changed', array( __CLASS__, 'on_status' ), 10, 4 );
	}

	/**
	 * Site name used in subjects and signatures.
	 *
	 * @return string
	 */
	private static function site() {
		$name = (string) Paygrab_Settings::get( 'mail_from_name' );
		return '' !== $name ? $name : wp_specialchars_decode( get_bloginfo( 'name' ), ENT_QUOTES );
	}

	/**
	 * Address that receives notices for the seller.
	 *
	 * @return string
	 */
	public static function admin_address() {
		$to = (string) Paygrab_Settings::get( 'mail_admin' );
		return is_email( $to ) ? $to : (string) get_option( 'admin_email' );
	}

	/**
	 * Send one mail.
	 *
	 * @param string           $type    Mail type (used in the filter name).
	 * @param string           $to      Recipient.
	 * @param string           $subject Subject.
	 * @param string           $body    Body.
	 * @param Paygrab_Order|null $order   Related order (for the history).
	 * @param string           $html    HTML version; the text version is sent with it for text-only mail apps.
	 * @param array            $extra   More values for $context['values'] (e.g. customer, link, valid_until).
	 * @return bool
	 */
	public static function send( $type, $to, $subject, $body, $order = null, $html = '', $extra = array() ) {
		/**
		 * Filters a PAYGRAB email before it is sent.
		 *
		 * Return an empty array to not send it. PAYGRAB Pro's mail editor replaces the subject and
		 * the text here, filling in the values from $context['values'].
		 *
		 * @param array            $mail    subject, body (text), html (optional).
		 * @param Paygrab_Order|null $order   Related order.
		 * @param array            $context type, to, values (name => value, see placeholders()).
		 */
		$mail = apply_filters(
			'paygrab_mail_' . $type,
			array(
				'subject' => $subject,
				'body'    => $body,
				'html'    => $html,
			),
			$order,
			array(
				'type'   => $type,
				'to'     => $to,
				'values' => array_merge( self::placeholders( $order ), $extra ),
			)
		);
		if ( empty( $mail ) || empty( $to ) ) {
			return false;
		}
		$from      = (string) Paygrab_Settings::get( 'mail_from' );
		$from_name = self::site();
		$set_from  = static fn() => $from;
		$set_name  = static fn() => $from_name;
		if ( is_email( $from ) ) {
			add_filter( 'wp_mail_from', $set_from, 99 );
		}
		add_filter( 'wp_mail_from_name', $set_name, 99 );
		if ( ! empty( $mail['html'] ) ) {
			// One email with both versions: HTML for most mail apps, text for the rest.
			$text     = $mail['body'];
			$set_text = static function ( $phpmailer ) use ( $text ) {
				$phpmailer->AltBody = $text; // phpcs:ignore WordPress.NamingConventions.ValidVariableName.UsedPropertyNotSnakeCase
			};
			add_action( 'phpmailer_init', $set_text );
			$sent = wp_mail( $to, $mail['subject'], $mail['html'], array( 'Content-Type: text/html; charset=UTF-8' ) );
			remove_action( 'phpmailer_init', $set_text );
		} else {
			$sent = wp_mail( $to, $mail['subject'], $mail['body'], array( 'Content-Type: text/plain; charset=UTF-8' ) );
		}
		remove_filter( 'wp_mail_from', $set_from, 99 );
		remove_filter( 'wp_mail_from_name', $set_name, 99 );

		if ( $order instanceof Paygrab_Order ) {
			Paygrab_Orders::add_event(
				$order->id,
				'mail_' . $type,
				$sent
					/* translators: %s: email subject */
					? sprintf( __( 'Sent “%s”.', 'paygrab' ), $mail['subject'] )
					/* translators: %s: email subject */
					: sprintf( __( 'Could not send “%s”.', 'paygrab' ), $mail['subject'] )
			);
		}
		return (bool) $sent;
	}

	/**
	 * Values an email can fill in (for PAYGRAB Pro's mail editor).
	 *
	 * @param Paygrab_Order|null $order Related order.
	 * @return array<string,string> name => value. Names: site, site_url, signature, and with an order:
	 *                              customer, product, amount, order_number, deadline, transfer_to,
	 *                              transfer_code, transfer_name, mypage_url.
	 */
	public static function placeholders( $order = null ) {
		$values = array(
			'site'      => self::site(),
			'site_url'  => home_url( '/' ),
			'signature' => ltrim( self::footer(), "\n" ),
		);
		if ( $order instanceof Paygrab_Order ) {
			$items  = $order->items();
			$values = array_merge(
				$values,
				array(
					'customer'      => $order->billing_name,
					'product'       => implode( paygrab_comma(), wp_list_pluck( $items, 'name' ) ),
					'amount'        => paygrab_price( $order->total ),
					'order_number'  => $order->order_number,
					'deadline'      => $order->pay_deadline ? paygrab_deadline( $order->pay_deadline ) : '',
					'transfer_to'   => 'bank_manual' === $order->gateway ? Paygrab_Gateway_Bank_Manual::account_text() : '',
					'transfer_code' => (string) $order->transfer_code,
					'transfer_name' => $order->transfer_name_example(),
					'mypage_url'    => paygrab_mypage_url( $order->order_number ),
				)
			);
		}
		/**
		 * Filters the values an email can fill in.
		 *
		 * @param array            $values name => value.
		 * @param Paygrab_Order|null $order  Related order.
		 */
		return (array) apply_filters( 'paygrab_mail_placeholders', $values, $order );
	}

	/**
	 * Subject with the site name in front.
	 *
	 * @param string $text Subject text.
	 * @return string
	 */
	private static function subject( $text ) {
		return '【' . self::site() . '】' . $text;
	}

	/**
	 * Common footer of buyer emails.
	 *
	 * @return string
	 */
	private static function footer() {
		$lines = array( '', '──────────', self::site(), home_url( '/' ) );
		$law   = paygrab_page_url( 'tokushoho' );
		if ( $law ) {
			$lines[] = __( 'Legal notice:', 'paygrab' ) . ' ' . $law;
		}
		return implode( "\n", $lines );
	}

	/**
	 * Order lines (number, items, amount).
	 *
	 * @param Paygrab_Order $order Order.
	 * @param bool        $tax   Show the tax.
	 * @return string
	 */
	private static function order_lines( Paygrab_Order $order, $tax = false ) {
		$lines   = array( '■' . __( 'Your order', 'paygrab' ) );
		$lines[] = __( 'Order number', 'paygrab' ) . paygrab_colon() . $order->order_number;
		foreach ( $order->items() as $item ) {
			$lines[] = __( 'Product', 'paygrab' ) . paygrab_colon() . $item->name;
		}
		$amount = paygrab_price( $order->total ) . __( ' (tax included)', 'paygrab' );
		if ( $tax ) {
			$parts = array();
			foreach ( $order->tax_breakdown() as $rate => $row ) {
				/* translators: 1: tax rate, 2: tax amount */
				$parts[] = sprintf( __( 'tax %1$d%%: %2$s', 'paygrab' ), $rate, paygrab_price( $row['tax'] ) );
			}
			$amount = paygrab_price( $order->total ) . paygrab_open() . implode( paygrab_comma(), $parts ) . paygrab_close();
		}
		$lines[] = __( 'Amount', 'paygrab' ) . paygrab_colon() . $amount;
		return implode( "\n", $lines );
	}

	/**
	 * Mails after an order was placed.
	 *
	 * @param Paygrab_Order   $order   Order.
	 * @param Paygrab_Gateway $gateway Gateway.
	 * @return void
	 */
	public static function on_placed( Paygrab_Order $order, Paygrab_Gateway $gateway ) {
		if ( ! $order->is_pending() ) {
			return; // Paid at once (Pro: card) – the "paid" mail covers it.
		}
		$instructions = $gateway->instructions_text( $order );
		/* translators: %s: buyer name */
		$body = sprintf( __( 'Dear %s,', 'paygrab' ), $order->billing_name ) . "\n\n"
			. __( 'Thank you for your order.', 'paygrab' ) . "\n"
			. ( $order->pay_deadline
				/* translators: %s: payment deadline */
				? sprintf( __( 'Please pay by %s.', 'paygrab' ), paygrab_deadline( $order->pay_deadline ) ) . "\n"
				: '' )
			. "\n" . self::order_lines( $order ) . "\n\n"
			. ( $instructions ? $instructions . "\n\n" : '' )
			. __( 'We will email you when we have confirmed your payment.', 'paygrab' ) . "\n"
			. __( 'My page:', 'paygrab' ) . ' ' . paygrab_mypage_url( $order->order_number ) . "\n\n"
			. __( 'If you do not pay by the deadline, the order is cancelled automatically.', 'paygrab' )
			. self::footer();
		self::send( 'order_received', $order->billing_email, self::subject( __( 'Thank you for your order (how to pay)', 'paygrab' ) ), $body, $order );

		/* translators: %s: order number */
		$admin_subject = sprintf( __( '[PAYGRAB] New order (awaiting payment) %s', 'paygrab' ), $order->order_number );
		$admin_body    = __( 'A new order came in.', 'paygrab' ) . "\n\n"
			. __( 'Order number', 'paygrab' ) . paygrab_colon() . $order->order_number . "\n"
			. __( 'Customer', 'paygrab' ) . paygrab_colon() . $order->billing_name . paygrab_open() . $order->billing_email . paygrab_close() . "\n"
			. __( 'Product', 'paygrab' ) . paygrab_colon() . $order->summary() . "\n"
			. __( 'Amount', 'paygrab' ) . paygrab_colon() . paygrab_price( $order->total ) . "\n"
			. ( 'bank_manual' === $order->gateway ? __( 'Transfer number', 'paygrab' ) . paygrab_colon() . $order->transfer_code . "\n" : '' )
			. ( $order->pay_deadline ? __( 'Deadline', 'paygrab' ) . paygrab_colon() . paygrab_deadline( $order->pay_deadline ) . "\n" : '' )
			. "\n" . ( 'bank_manual' === $order->gateway ? __( 'When you have confirmed the payment, press “Confirm payment” in the order list.', 'paygrab' ) . "\n" : '' )
			. paygrab_admin_order_url( $order->id );
		self::send( 'admin_new_order', self::admin_address(), $admin_subject, $admin_body, $order );
	}

	/**
	 * Mails after a status change.
	 *
	 * @param Paygrab_Order $order Order.
	 * @param string      $from  Previous status.
	 * @param string      $to    New status.
	 * @param array       $args  notify, by.
	 * @return void
	 */
	public static function on_status( Paygrab_Order $order, $from, $to, $args ) {
		if ( empty( $args['notify'] ) ) {
			return;
		}
		/* translators: %s: buyer name */
		$hello = sprintf( __( 'Dear %s,', 'paygrab' ), $order->billing_name ) . "\n\n";
		if ( 'paid' === $to ) {
			$lines = array();
			foreach ( Paygrab_Downloads::for_order( $order->id ) as $row ) {
				$remaining = Paygrab_Downloads::remaining( $row );
				$lines[]   = null === $remaining ? __( 'Downloads: unlimited', 'paygrab' ) : sprintf( /* translators: %d: count */ __( 'Downloads: up to %d times', 'paygrab' ), $remaining );
				$lines[]   = $row->expires_at ? sprintf( /* translators: %s: date */ __( 'Available until: %s', 'paygrab' ), paygrab_date( $row->expires_at ) ) : __( 'Available: no time limit', 'paygrab' );
				break;
			}
			$body = $hello
				. __( 'We have confirmed your payment. You can download the product from My page.', 'paygrab' ) . "\n\n"
				. '■' . __( 'Download', 'paygrab' ) . "\n"
				. paygrab_mypage_url( $order->order_number ) . "\n"
				. __( '(Log in to download.)', 'paygrab' ) . "\n"
				. implode( "\n", $lines ) . "\n\n"
				. self::order_lines( $order, true ) . "\n"
				. __( 'Payment method', 'paygrab' ) . paygrab_colon() . $order->payment_label() . "\n"
				. __( 'Payment date', 'paygrab' ) . paygrab_colon() . paygrab_date( $order->paid_at ) . "\n"
				. __( 'Seller', 'paygrab' ) . paygrab_colon() . ( Paygrab_Settings::get( 'law_seller' ) ? Paygrab_Settings::get( 'law_seller' ) : self::site() )
				. self::footer();
			self::send( 'order_paid', $order->billing_email, self::subject( __( 'We have confirmed your payment (download)', 'paygrab' ) ), $body, $order );
		} elseif ( 'cancelled' === $to ) {
			$by_buyer = 'buyer' === ( $args['by'] ?? '' );
			$reason   = $by_buyer
				? __( 'Your order was cancelled as you requested.', 'paygrab' )
				: ( 'expired' === ( $args['by'] ?? '' ) ? __( 'We cancelled your order because we did not receive the payment by the deadline.', 'paygrab' ) : __( 'Your order was cancelled.', 'paygrab' ) );
			$body     = $hello . $reason . "\n\n" . self::order_lines( $order ) . "\n\n"
				. __( 'If you still want the product, please order again from the product page.', 'paygrab' )
				. self::footer();
			self::send( 'order_cancelled', $order->billing_email, self::subject( __( 'Your order was cancelled', 'paygrab' ) ), $body, $order );
			if ( $by_buyer ) {
				/* translators: %s: order number */
				$subject = sprintf( __( '[PAYGRAB] Order cancelled by the customer %s', 'paygrab' ), $order->order_number );
				self::send( 'admin_cancelled', self::admin_address(), $subject, self::order_lines( $order ) . "\n" . __( 'Customer', 'paygrab' ) . paygrab_colon() . $order->billing_name, $order );
			}
		} elseif ( 'refunded' === $to ) {
			$body = $hello . __( 'Your order was refunded. The download is no longer available.', 'paygrab' ) . "\n\n" . self::order_lines( $order ) . self::footer();
			self::send( 'order_refunded', $order->billing_email, self::subject( __( 'Your order was refunded', 'paygrab' ) ), $body, $order );
		}
	}

	/**
	 * Reminder the day before the payment deadline.
	 *
	 * @param Paygrab_Order $order Order.
	 * @return bool
	 */
	public static function reminder( Paygrab_Order $order ) {
		$gateway = Paygrab_Gateways::get( $order->gateway );
		/* translators: %s: buyer name */
		$body = sprintf( __( 'Dear %s,', 'paygrab' ), $order->billing_name ) . "\n\n"
			/* translators: %s: payment deadline */
			. sprintf( __( 'The payment deadline for your order is %s. If you have not paid yet, please pay by then.', 'paygrab' ), paygrab_deadline( $order->pay_deadline ) ) . "\n"
			. __( 'If you have already paid, please ignore this email.', 'paygrab' ) . "\n\n"
			. self::order_lines( $order ) . "\n\n"
			. ( $gateway ? $gateway->instructions_text( $order ) . "\n\n" : '' )
			. __( 'My page:', 'paygrab' ) . ' ' . paygrab_mypage_url( $order->order_number )
			. self::footer();
		return self::send( 'payment_reminder', $order->billing_email, self::subject( __( 'Your payment deadline is tomorrow', 'paygrab' ) ), $body, $order );
	}

	/**
	 * Email with a button (HTML) and the same content for text-only mail apps (M4).
	 *
	 * @param string $type    Mail type.
	 * @param string $to      Recipient.
	 * @param string $subject Subject (without the site name).
	 * @param string $name    Recipient's name.
	 * @param array  $text    html (lead for the HTML version, "press the button"), plain (lead for the text version,
	 *                        "open the URL"), button, ignore_html, ignore_plain, period (e.g. "24 hours").
	 * @param string $url     Link.
	 * @param int    $expires Unix time when the link stops working.
	 * @return bool
	 */
	private static function send_link( $type, $to, $subject, $name, array $text, $url, $expires ) {
		$site = self::site();
		/* translators: %s: name */
		$dear = sprintf( __( 'Dear %s,', 'paygrab' ), $name );
		/* translators: date and time format for link expiry, see https://www.php.net/manual/datetime.format.php */
		$when   = wp_date( __( 'F j H:i', 'paygrab' ), $expires );
		$values = array_merge(
			self::placeholders(),
			array(
				'customer'    => $name,
				'link'        => $url,
				'valid_until' => $when,
			)
		);
		/**
		 * Filters the wording of an email with a button (PAYGRAB Pro's mail editor changes it here).
		 * The link, the button and the expiry line are always added.
		 *
		 * @param array  $text   html, plain, button, ignore_html, ignore_plain, period.
		 * @param string $type   verify_email | password_reset | email_change
		 * @param array  $values Values to fill in (site, customer, link, valid_until, …).
		 */
		$text = (array) apply_filters( 'paygrab_mail_link_text', $text, $type, $values ) + $text;
		/* translators: 1: date and time, 2: period such as "24 hours" */
		$until = sprintf( __( 'Valid until: %1$s (%2$s)', 'paygrab' ), $when, $text['period'] );
		$plain = $dear . "\n\n" . $text['plain'] . "\n\n" . $url . "\n\n" . $until . "\n\n" . $text['ignore_plain'] . self::footer();

		$p    = static fn( $t, $small = false ) => '<p style="margin:0 0 16px;' . ( $small ? 'font-size:12px;color:#555555;' : '' ) . '">' . $t . '</p>';
		$law  = paygrab_page_url( 'tokushoho' );
		$html = '<!doctype html><html><body style="margin:0;padding:28px 12px;background:#f6f6f4;">'
			. '<div style="max-width:480px;margin:0 auto;background:#ffffff;border-radius:6px;padding:28px;font-family:-apple-system,BlinkMacSystemFont,\'Hiragino Sans\',\'Noto Sans JP\',sans-serif;font-size:14px;line-height:1.9;color:#222222;">'
			. '<div style="margin:0 0 16px;font-size:13px;font-weight:700;letter-spacing:.04em;color:#555555;">' . esc_html( $site ) . '</div>'
			. $p( esc_html( $dear ) )
			. $p( nl2br( esc_html( $text['html'] ) ) )
			. '<p style="margin:0 0 16px;"><a href="' . esc_url( $url ) . '" style="display:block;padding:13px 16px;background:#222222;color:#ffffff;border-radius:4px;font-weight:700;text-align:center;text-decoration:none;">' . esc_html( $text['button'] ) . '</a></p>'
			. $p( esc_html__( 'If the button does not work, paste this URL into your browser.', 'paygrab' ) . '<br><span style="word-break:break-all;color:#1d4ed8;">' . esc_html( $url ) . '</span>', true )
			/* translators: 1: date and time, 2: period such as "24 hours" */
			. $p( wp_kses( sprintf( __( 'This link is valid until <strong>%1$s</strong> (%2$s).', 'paygrab' ), esc_html( $when ), esc_html( $text['period'] ) ), array( 'strong' => array() ) ), true )
			. '<hr style="border:0;border-top:1px solid #ecece9;margin:4px 0 16px;">'
			. $p( nl2br( esc_html( $text['ignore_html'] ) ), true )
			. '<p style="margin:0;font-size:12px;color:#555555;">' . esc_html( $site ) . '　' . esc_html( home_url( '/' ) ) . ( $law ? '<br>' . esc_html__( 'Legal notice:', 'paygrab' ) . esc_html( $law ) : '' ) . '</p>'
			. '</div></body></html>';
		return self::send( $type, $to, self::subject( $subject ), $plain, null, $html, $values );
	}

	/**
	 * Sign-up verification email (M4).
	 *
	 * @param string $email   Address.
	 * @param string $name    Name.
	 * @param string $url     Verification link.
	 * @param int    $expires Unix time when the link stops working.
	 * @return bool
	 */
	public static function verify_email( $email, $name, $url, $expires = 0 ) {
		return self::send_link(
			'verify_email',
			$email,
			__( 'Confirm your email address', 'paygrab' ),
			$name,
			array(
				'html'         => __( 'Thank you for signing up. Press the button below to finish your registration.', 'paygrab' ),
				'plain'        => __( 'Thank you for signing up. Open the URL below to finish your registration.', 'paygrab' ),
				'button'       => __( 'Finish registration', 'paygrab' ),
				'ignore_html'  => __( 'If you did not sign up, please delete this email. Nobody becomes a member unless the button is pressed.', 'paygrab' ),
				'ignore_plain' => __( 'If you did not sign up, please delete this email. Nobody becomes a member unless the URL is opened.', 'paygrab' ),
				'period'       => __( '24 hours', 'paygrab' ),
			),
			$url,
			$expires ? $expires : time() + DAY_IN_SECONDS
		);
	}

	/**
	 * "Set a new password" email.
	 *
	 * @param WP_User $user User.
	 * @param string  $url  Link.
	 * @return bool
	 */
	public static function password_reset( WP_User $user, $url ) {
		return self::send_link(
			'password_reset',
			$user->user_email,
			__( 'Set a new password', 'paygrab' ),
			$user->display_name,
			array(
				'html'         => __( 'We received a request to set a new password. Press the button below and choose a new password.', 'paygrab' ),
				'plain'        => __( 'We received a request to set a new password. Open the URL below and choose a new password.', 'paygrab' ),
				'button'       => __( 'Set a new password', 'paygrab' ),
				'ignore_html'  => __( 'If you did not ask for this, please delete this email. Your password stays the same.', 'paygrab' ),
				'ignore_plain' => __( 'If you did not ask for this, please delete this email. Your password stays the same.', 'paygrab' ),
				'period'       => __( '1 hour', 'paygrab' ),
			),
			$url,
			time() + HOUR_IN_SECONDS
		);
	}

	/**
	 * Confirm a new email address (sent to the new address).
	 *
	 * @param WP_User $user  User.
	 * @param string  $email New address.
	 * @param string  $url   Link.
	 * @return bool
	 */
	public static function email_change( WP_User $user, $email, $url ) {
		return self::send_link(
			'email_change',
			$email,
			__( 'Confirm your new email address', 'paygrab' ),
			$user->display_name,
			array(
				'html'         => __( 'Press the button below to change the email address of your account to this address.', 'paygrab' ),
				'plain'        => __( 'Open the URL below to change the email address of your account to this address.', 'paygrab' ),
				'button'       => __( 'Change my email address', 'paygrab' ),
				'ignore_html'  => __( 'If you did not ask for this, please delete this email. Nothing changes unless the button is pressed.', 'paygrab' ),
				'ignore_plain' => __( 'If you did not ask for this, please delete this email. Nothing changes unless the URL is opened.', 'paygrab' ),
				'period'       => __( '24 hours', 'paygrab' ),
			),
			$url,
			time() + DAY_IN_SECONDS
		);
	}

	/**
	 * Test mail to the seller.
	 *
	 * @return bool
	 */
	public static function test() {
		$body = __( 'This is a test email from PAYGRAB. If you can read this, emails are being delivered.', 'paygrab' ) . self::footer();
		return self::send( 'test', self::admin_address(), self::subject( __( 'Test email', 'paygrab' ) ), $body );
	}
}