<form method="POST">
    <h3>Editing: EmailNotification.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * Handles emailing user notes.
 */

namespace Automattic\WooCommerce\Internal\Admin\Notes;

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

use Automattic\WooCommerce\Admin\Notes\Notes;

/**
 * Include dependencies.
 */
if ( ! class_exists( 'WC_Email', false ) ) {
	include_once WC_ABSPATH . 'includes/emails/class-wc-email.php';
}

/**
 * EmailNotification Class.
 */
class EmailNotification extends \WC_Email {
	/**
	 * Constructor.
	 *
	 * @param Note $note The notification to send.
	 */
	public function __construct( $note ) {
		$this-&gt;note          = $note;
		$this-&gt;id            = 'merchant_notification';
		$this-&gt;template_base = WC_ADMIN_ABSPATH . 'includes/react-admin/emails/';
		$this-&gt;placeholders  = array(
			'{greetings}' =&gt; __( 'Hi there,', 'woocommerce' ),
		);

		// Call parent constructor.
		parent::__construct();
	}

	/**
	 * This email has no user-facing settings.
	 */
	public function init_form_fields() {}

	/**
	 * This email has no user-facing settings.
	 */
	public function init_settings() {}

	/**
	 * Return template filename.
	 *
	 * @param string $type Type of email to send.
	 * @return string
	 */
	public function get_template_filename( $type = 'html' ) {
		if ( ! in_array( $type, array( 'html', 'plain' ), true ) ) {
			return;
		}
		$content_data      = $this-&gt;note-&gt;get_content_data();
		$template_filename = &quot;{$type}-merchant-notification.php&quot;;
		if ( isset( $content_data-&gt;{&quot;template_{$type}&quot;} ) &amp;&amp; file_exists( $this-&gt;template_base . $content_data-&gt;{ &quot;template_{$type}&quot; } ) ) {
			$template_filename = $content_data[ &quot;template_{$type}&quot; ];
		}
		return $template_filename;
	}

	/**
	 * Return email type.
	 *
	 * @return string
	 */
	public function get_email_type() {
		return class_exists( 'DOMDocument' ) ? 'html' : 'plain';
	}

	/**
	 * Get email heading.
	 *
	 * @return string
	 */
	public function get_default_heading() {
		$content_data = $this-&gt;note-&gt;get_content_data();
		if ( isset( $content_data-&gt;heading ) ) {
			return $content_data-&gt;heading;
		}

		return $this-&gt;note-&gt;get_title();
	}

	/**
	 * Get email headers.
	 *
	 * @return string
	 */
	public function get_headers() {
		$header = 'Content-Type: ' . $this-&gt;get_content_type() . &quot;\r\n&quot;;
		return apply_filters( 'woocommerce_email_headers', $header, $this-&gt;id, $this-&gt;object, $this );
	}

	/**
	 * Get email subject.
	 *
	 * @return string
	 */
	public function get_default_subject() {
		return $this-&gt;note-&gt;get_title();
	}

	/**
	 * Get note content.
	 *
	 * @return string
	 */
	public function get_note_content() {
		return $this-&gt;note-&gt;get_content();
	}

	/**
	 * Get note image.
	 *
	 * @return string
	 */
	public function get_image() {
		return $this-&gt;note-&gt;get_image();
	}

	/**
	 * Get email action.
	 *
	 * @return stdClass
	 */
	public function get_actions() {
		return $this-&gt;note-&gt;get_actions();
	}

	/**
	 * Get content html.
	 *
	 * @return string
	 */
	public function get_content_html() {
		return wc_get_template_html(
			$this-&gt;get_template_filename( 'html' ),
			array(
				'email_actions'           =&gt; $this-&gt;get_actions(),
				'email_content'           =&gt; $this-&gt;format_string( $this-&gt;get_note_content() ),
				'email_heading'           =&gt; $this-&gt;format_string( $this-&gt;get_heading() ),
				'email_image'             =&gt; $this-&gt;get_image(),
				'sent_to_admin'           =&gt; true,
				'plain_text'              =&gt; false,
				'email'                   =&gt; $this,
				'opened_tracking_url'     =&gt; $this-&gt;opened_tracking_url,
				'trigger_note_action_url' =&gt; $this-&gt;trigger_note_action_url,
			),
			'',
			$this-&gt;template_base
		);
	}

	/**
	 * Get content plain.
	 *
	 * @return string
	 */
	public function get_content_plain() {
		return wc_get_template_html(
			$this-&gt;get_template_filename( 'plain' ),
			array(
				'email_heading'           =&gt; $this-&gt;format_string( $this-&gt;get_heading() ),
				'email_content'           =&gt; $this-&gt;format_string( $this-&gt;get_note_content() ),
				'email_actions'           =&gt; $this-&gt;get_actions(),
				'sent_to_admin'           =&gt; true,
				'plain_text'              =&gt; true,
				'email'                   =&gt; $this,
				'trigger_note_action_url' =&gt; $this-&gt;trigger_note_action_url,
			),
			'',
			$this-&gt;template_base
		);
	}

	/**
	 * Trigger the sending of this email.
	 *
	 * @param string $user_email Email to send the note.
	 * @param int    $user_id User id to to track the note.
	 * @param string $user_name User's name.
	 */
	public function trigger( $user_email, $user_id, $user_name ) {
		$this-&gt;recipient               = $user_email;
		$this-&gt;opened_tracking_url     = sprintf(
			'%1$s/wp-json/wc-analytics/admin/notes/tracker/%2$d/user/%3$d',
			site_url(),
			$this-&gt;note-&gt;get_id(),
			$user_id
		);
		$this-&gt;trigger_note_action_url = sprintf(
			'%1$s&amp;external_redirect=1&amp;note=%2$d&amp;user=%3$d&amp;action=',
			wc_admin_url(),
			$this-&gt;note-&gt;get_id(),
			$user_id
		);

		if ( $user_name ) {
			/* translators: %s = merchant name */
			$this-&gt;placeholders['{greetings}'] = sprintf( __( 'Hi %s,', 'woocommerce' ), $user_name );
		}

		$this-&gt;send(
			$this-&gt;get_recipient(),
			$this-&gt;get_subject(),
			$this-&gt;get_content(),
			$this-&gt;get_headers(),
			$this-&gt;get_attachments()
		);
		Notes::record_tracks_event_with_user( $user_id, 'email_note_sent', array( 'note_name' =&gt; $this-&gt;note-&gt;get_name() ) );
	}
}
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