new_status_mail.php

/**
 * Extra emails wc
 */
class wopeckoStatusEmails {

	function __construct($id,$title,$description) {
		$this->ID 	 		= $id;
		$this->title 		= $title;
		$this->description 	= $description;
		add_filter( 'woocommerce_email_classes', array($this, 'add_custom_order_status_woocommerce_email') );
		add_action( 'woocommerce_order_status_changed', array( $this, 'conditional_trigger' ), 99, 4 );
	}

	function add_custom_order_status_woocommerce_email( $email_classes ) {
		if ( ! isset( $email_classes[ 'wopeckoBookedOrderEmail' ] ) ) {
			require_once( 'subclasses/woo-extra-emails.php' );
	    	// add the email class to the list of email classes that WooCommerce loads
	    	$email_classes['wopeckoBookedOrderEmail'] = new wopeckoCustomStatusEmail($this->ID, $this->title, $this->description);
	    }
	    return $email_classes;
	}

	public function conditional_trigger($order_id, $from, $to, $order) {
		if($to === $this->ID) {
			new WC_Emails();
			do_action( 'wopecko_'.$this->ID.'_status_trigger', $order_id );
		}
		return;
	}
}

$wopeckoBookedOrderEmail = new wopeckoStatusEmails("booked","Booked","This email is sent when the order enters the booked status");

woo_custom_status_mail_extend.php

<?php

class wopeckoCustomStatusEmail extends WC_Email
{
	
	public function __construct($id,$title,$description) {
		$this->setID 	= $id;
		$this->setTitle = $title; 
		// set ID, this simply needs to be a unique name
		$this->id = 'wc_'.$id.'_order';
		// this is the title in WooCommerce Email settings
		$this->title = $title.' Order';
		// this is the description in WooCommerce email settings
		$this->description = $description;
		// these are the default heading and subject lines that can be overridden using the settings
		$this->heading = $this->title.' status';
		$this->subject = $this->title.' status';
		// these define the locations of the templates that this email should use, we'll just use the new order template since this email is similar
		$this->template_html  = 'emails/customer-'.$id.'-order.php';
		$this->template_plain = 'emails/plain/customer-'.$id.'-order.php';
		// Call parent constructor to load any other defaults not explicity defined here
		parent::__construct();
		// this sets the recipient to the settings defined below in init_form_fields()
		$this->recipient = $this->get_option( 'recipient' );
		// trigger
		add_action( 'wopecko_'.$this->setID.'_status_trigger', array($this, 'trigger') );
	}

	/**
	 * Determine if the email should actually be sent and setup email merge variables
	 *
	 * @since 0.1
	 * @param int $order_id
	 */
	public function trigger( $order_id ) {
		// bail if no order ID is present
		if ( ! $order_id )
			return;
		// setup order object
		$this->object = new WC_Order( $order_id );
		if ( ! $this->recipient )
			$this->recipient = $this->object->get_billing_email();
		// bail if shipping method is not booked
		if ( $this->object->get_status() !== $this->setID )
			return;
		// replace variables in the subject/headings
		$this->find[] = '{order_date}';
		$this->replace[] = date_i18n( woocommerce_date_format(), strtotime( $this->object->order_date ) );
		$this->find[] = '{order_number}';
		$this->replace[] = $this->object->get_order_number();
		if ( ! $this->is_enabled() || ! $this->get_recipient() )
			return;
		// woohoo, send the email!
		$this->send( $this->get_recipient(), $this->get_subject(), $this->get_content(), $this->get_headers(), $this->get_attachments() );
	}
	/**
	 * get_content_html function.
	 *
	 * @since 0.1
	 * @return string
	 */
	public function get_content_html() {
		ob_start();
		woocommerce_get_template( $this->template_html, array(
			'order'         => $this->object,
			'email_heading' => $this->get_heading()
		) );
		return ob_get_clean();
	}
	/**
	 * get_content_plain function.
	 *
	 * @since 0.1
	 * @return string
	 */
	public function get_content_plain() {
		ob_start();
		woocommerce_get_template( $this->template_plain, array(
			'order'         => $this->object,
			'email_heading' => $this->get_heading()
		) );
		return ob_get_clean();
	}
	/**
	 * Initialize Settings Form Fields
	 *
	 * @since 2.0
	 */
	public function init_form_fields() {
		$this->form_fields = array(
			'enabled'    => array(
				'title'   => 'Enable/Disable',
				'type'    => 'checkbox',
				'label'   => 'Enable this email notification',
				'default' => 'yes'
			),
			'recipient'  => array(
				'title'       => 'Recipient(s)',
				'type'        => 'text',
				'description' => sprintf( 'Enter recipients (comma separated) for this email. Defaults to <code>%s</code>.', esc_attr( get_option( 'admin_email' ) ) ),
				'placeholder' => '',
				'default'     => ''
			),
			'subject'    => array(
				'title'       => 'Subject',
				'type'        => 'text',
				'description' => sprintf( 'This controls the email subject line. Leave blank to use the default subject: <code>%s</code>.', $this->subject ),
				'placeholder' => '',
				'default'     => ''
			),
			'heading'    => array(
				'title'       => 'Email Heading',
				'type'        => 'text',
				'description' => sprintf( __( 'This controls the main heading contained within the email notification. Leave blank to use the default heading: <code>%s</code>.' ), $this->heading ),
				'placeholder' => '',
				'default'     => ''
			),
			'email_type' => array(
				'title'       => 'Email type',
				'type'        => 'select',
				'description' => 'Choose which format of email to send.',
				'default'     => 'html',
				'class'       => 'email_type',
				'options'     => array(
					'plain'	    => __( 'Plain text', 'woocommerce' ),
					'html' 	    => __( 'HTML', 'woocommerce' ),
					'multipart' => __( 'Multipart', 'woocommerce' ),
				)
			)
		);
	}
}