learnpress / inc / emails / class-lp-email.php

class-lp-email.php in LearnPress – WordPress LMS Plugin for Create and Sell Online Courses 4.4.8, at inc/emails/class-lp-email.php

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1	<?php
2	/**
3	* Class Email.
4	*
5	* @author ThimPress
6	* @category Widgets
7	* @package Learnpress/Email
8	* @since 3.0.0
9	* @version 3.0.4
10	*/
11
12	/**
13	* Prevent loading this file directly
14	*/
15
16	use Pelago\Emogrifier\CssInliner;
17	use TijsVerkoyen\CssToInlineStyles\CssToInlineStyles;
18
19	defined( 'ABSPATH' ) \|\| exit();
20
21	if ( ! class_exists( 'LP_Email' ) ) {
22
23	/**
24	* Class LP_Email
25	*/
26	class LP_Email extends LP_Abstract_Settings {
27	/**
28	* Email method ID.
29	*
30	* @var String
31	*/
32	public $id;
33
34	/**
35	* Email method title.
36	*
37	* @var string
38	*/
39	public $title;
40
41	/**
42	* 'yes' if the method is enabled.
43	*
44	* @var string
45	*/
46	//public $enabled;
47
48	/**
49	* Description for the email.
50	*
51	* @var string
52	*/
53	public $description;
54
55	/**
56	* Plain text template path.
57	*
58	* @var string
59	*/
60	public $template_plain;
61
62	/**
63	* HTML template path.
64	*
65	* @var string
66	*/
67	public $template_html = '';
68
69	/**
70	* Template path.
71	*
72	* @var string
73	*/
74	public $template_base = '';
75
76	/**
77	* Recipients for the email.
78	*
79	* @var string
80	*/
81	public $recipient;
82
83	/**
84	* @var bool Enable recipients
85	*
86	* @since 4.2.6.4
87	*/
88	public $enable_recipients = false;
89
90	/**
91	* For send CC or BB email.
92	*
93	* @var string
94	*/
95	public $recipients = '';
96
97	/**
98	* Heading for the email content.
99	*
100	* @var string
101	*/
102	public $heading = '';
103
104	/**
105	* Subject for the email.
106	*
107	* @var string
108	*/
109	public $subject = '';
110
111	/**
112	* Default heading for the email content.
113	*
114	* @var string
115	*/
116	public $default_heading = '';
117
118	/**
119	* Default subject for the email.
120	*
121	* @var string
122	*/
123	public $default_subject = '';
124
125	/**
126	* Default content for the email.
127	*
128	* @var string
129	*/
130	public $content;
131
132	/**
133	* Object this email is for, for example a customer, product, or email.
134	*
135	* @var object
136	*/
137	public $object;
138
139	/**
140	* Strings to find in subjects/headings.
141	*
142	* @var array
143	*/
144	public $find;
145
146	/**
147	* Strings to replace in subjects/headings.
148	*
149	* @var array
150	*/
151	public $replace;
152
153	/**
154	* Mime boundary (for multipart emails).
155	*
156	* @var string
157	*/
158	public $mime_boundary;
159
160	/**
161	* Mime boundary header (for multipart emails).
162	*
163	* @var string
164	*/
165	public $mime_boundary_header;
166
167	/**
168	* True when email is being sent.
169	*
170	* @var bool
171	*/
172	public $sending;
173
174	public $debug = false;
175
176	protected $_object_loaded = false;
177
178	/**
179	* List of preg* regular expression patterns to search for,
180	* used in conjunction with $replace.
181	* https://raw.github.com/ushahidi/wp-silcc/master/class.html2text.inc
182	*
183	* @var array $search
184	* @see $replace
185	*/
186	public $plain_search = array(
187	"/\r/", // Non-legal carriage return
188	'/&(nbsp\|#160);/i', // Non-breaking space
189	'/&(quot\|rdquo\|ldquo\|#8220\|#8221\|#147\|#148);/i', // Double quotes
190	'/&(apos\|rsquo\|lsquo\|#8216\|#8217);/i', // Single quotes
191	'/>/i', // Greater-than
192	'/</i', // Less-than
193	'/&/i', // Ampersand
194	'/&/i', // Ampersand
195	'/&/i', // Ampersand
196	'/&(copy\|#169);/i', // Copyright
197	'/&(trade\|#8482\|#153);/i', // Trademark
198	'/&(reg\|#174);/i', // Registered
199	'/&(mdash\|#151\|#8212);/i', // mdash
200	'/&(ndash\|minus\|#8211\|#8722);/i', // ndash
201	'/&(bull\|#149\|#8226);/i', // Bullet
202	'/&(pound\|#163);/i', // Pound sign
203	'/&(euro\|#8364);/i', // Euro sign
204	'/$/', // Dollar sign
205	'/&[^&\s;]+;/i', // Unknown/unhandled entities
206	'/[ ]{2,}/', // Runs of spaces, post-handling
207	);
208
209	/**
210	* List of pattern replacements corresponding to patterns searched.
211	*
212	* @var array $replace
213	* @see $search
214	*/
215	public $plain_replace = array(
216	'', // Non-legal carriage return
217	' ', // Non-breaking space
218	'"', // Double quotes
219	"'", // Single quotes
220	'>', // Greater-than
221	'<', // Less-than
222	'&', // Ampersand
223	'&', // Ampersand
224	'&', // Ampersand
225	'(c)', // Copyright
226	'(tm)', // Trademark
227	'(R)', // Registered
228	'--', // mdash
229	'-', // ndash
230	'*', // Bullet
231	'�', // Pound sign
232	'EUR', // Euro sign. � ?
233	'$', // Dollar sign
234	'', // Unknown/unhandled entities
235	' ', // Runs of spaces, post-handling
236	);
237
238	/**
239	* List of pattern search corresponding to patterns replace.
240	*
241	* @var array text shortcode
242	*/
243	public $text_search = array();
244
245	/**
246	* List of pattern to replace
247	*
248	* @var array text replace
249	*/
250	public $text_replace = array();
251
252	/**
253	* Text message description
254	*
255	* @var string
256	*/
257	public $email_text_message_description = '';
258
259	/**
260	* @var string
261	*/
262	public $template_path = '';
263
264	/**
265	* @var null
266	*/
267	public $variables = array();
268
269	/**
270	* @var null
271	*/
272	public $general_variables = [];
273
274	/**
275	* @var null
276	*/
277	public $support_variables = [];
278
279	/**
280	* @var LP_Settings
281	*/
282	public $settings = null;
283
284	/**
285	* @var string
286	*/
287	public $email_format = 'html';
288
289	/**
290	* @var bool
291	*/
292	public $enable = false;
293
294	/**
295	* @var string
296	*/
297	public $group = '';
298
299	/**
300	* @var string
301	*/
302	protected $_option_id = '';
303
304	/**
305	* LP_Email constructor.
306	*/
307	public function __construct() {
308	// Set template base path to LP templates path if it is not set.
309	if ( empty( $this->template_base ) ) {
310	$this->template_base = LearnPress::instance()->plugin_path( 'templates/' );
311	}
312
313	/**
314	* Set template folder if it is not set. Default is 'learnpress'
315	*/
316	if ( empty( $this->template_path ) ) {
317	$this->template_path = learn_press_template_path();
318	}
319
320	if ( empty( $this->template_html ) ) {
321	$this->template_html = "emails/{$this->id}.php";
322	}
323
324	if ( empty( $this->template_plain ) ) {
325	$this->template_plain = "emails/plain/{$this->id}.php";
326	}
327
328	if ( ! $this->object ) {
329	$this->object = array();
330	}
331
332	$this->_option_id = 'emails_' . $this->id;
333
334	$this->settings = LP_Settings::instance()->get_group( $this->_option_id, '' );
335
336	/**
337	* Init general options
338	*/
339	$this->heading = $this->settings->get( 'heading', $this->default_heading );
340	$this->subject = $this->settings->get( 'subject', $this->default_subject );
341	$this->enable = $this->settings->get( 'enable', 'no' ) === 'yes';
342
343	/*if ( $this->settings->get( 'email_content.format' ) ) {
344	$this->email_format = ( $this->settings->get( 'email_content.format' ) == 'plain_text' ) ? 'plain' : 'html';
345	} else {
346	if ( LP_Settings::instance()->get( 'emails_general.default_email_content', 'html' ) ) {
347	$this->email_format = LP_Settings::instance()->get( 'emails_general.default_email_content', 'html' );
348	}
349	}*/
350
351	$email_formats = array( 'plain', 'html' );
352	if ( ! in_array( $this->email_format, $email_formats ) ) {
353	$this->email_format = 'html';
354	}
355
356	// Set type variables can click add to content of email setting.
357	$this->support_variables = [
358	'{{site_url}}',
359	'{{site_title}}',
360	'{{login_url}}',
361	'{{site_admin_email}}',
362	'{{site_admin_name}}',
363	'{{header}}',
364	'{{footer}}',
365	'{{footer_text}}',
366	];
367	$this->general_variables = $this->support_variables;
368	}
369
370	/**
371	* @param null $value
372	*
373	* @return bool
374	*/
375	public function enable( $value = null ): bool {
376	if ( is_bool( $value ) ) {
377	$this->enable = $value;
378
379	// Load default settings if the email is not configured
380	if ( ! $this->is_configured() ) {
381	$settings = $this->get_settings();
382
383	foreach ( $settings as $field ) {
384	if ( $field['type'] == 'heading' \|\| $field['type'] == 'title' \|\| $field['type'] == 'sectionend' ) {
385	continue;
386	}
387
388	$id = str_replace( $this->_option_id, '', $field['id'] );
389	$id = str_replace( array( '[', ']' ), '', $id );
390
391	if ( $id == 'email_content' ) {
392	$this->settings->set(
393	'email_content',
394	array(
395	'format' => 'html',
396	'plain' => lp_get_email_content( 'plain', '', $field ),
397	'html' => lp_get_email_content( 'html', '', $field ),
398	)
399	);
400	} else {
401	$this->settings->set( $id, $field['default'] );
402	}
403	}
404	}
405	$this->settings->set( 'enable', $value ? 'yes' : 'no' );
406	$this->settings->update( 'learn_press_' . $this->_option_id, $this->settings->get() );
407	}
408
409	return $this->enable;
410	}
411
412	/**
413	* @return mixed
414	*/
415	public function is_configured() {
416	return LP_Settings::instance()->get( $this->_option_id );
417	}
418
419	/**
420	* Get variables support in mail.
421	*
422	* @return mixed
423	*/
424	public function get_variables_support() {
425	return apply_filters( 'learn-press/email-variables-support', $this->support_variables, $this );
426	}
427
428	/**
429	* Magic function
430	*
431	* @param $key
432	*
433	* @return mixed
434	*/
435	public function __get( $key ) {
436	if ( ! empty( $this->{$key} ) ) {
437	return $this->{$key};
438	} else {
439	return $this->settings->get( $key );
440	}
441	}
442
443	/**
444	* @return bool
445	*/
446	private function is_current() {
447	return ! empty( $_REQUEST['section'] ) && sanitize_text_field( $_REQUEST['section'] ) == $this->id;
448	}
449
450	/**
451	* @param $options
452	* @param $key
453	*
454	* @return bool
455	*/
456	public function _remove_email_content_from_option( $options, $key ) {
457	if ( ! $this->is_current() ) {
458	return false;
459	}
460
461	if ( is_array( $options ) && ( array_key_exists( 'email_content_html', $options ) \|\| array_key_exists( 'email_content_plain', $options ) ) ) {
462
463	if ( array_key_exists( 'email_content_html', $options ) ) {
464	$this->save_template( $options['email_content_html'], $this->template_html );
465	unset( $options['email_content_html'] );
466	}
467
468	if ( array_key_exists( 'email_content_plain', $options ) ) {
469	$this->save_template( $options['email_content_plain'], $this->template_plain );
470	unset( $options['email_content_plain'] );
471	}
472	}
473
474	return $options;
475	}
476
477	/**
478	* Apply the value of variables for string
479	*
480	* @param string $value
481	*
482	* @return string
483	* @editor tungnx
484	*/
485	public function format_string( string $value ): string {
486	$search = [];
487	$replace = [];
488	if ( is_array( $this->variables ) ) {
489	$search = array_keys( $this->variables );
490	$replace = array_values( $this->variables );
491	}
492	$search = apply_filters( 'learn-press/email-format-string-find', $search, $this );
493	$replace = apply_filters( 'learn-press/email-format-string-replace', $replace, $this );
494
495	return str_replace( $search, $replace, $value );
496	}
497
498	/**
499	* Get email recipient.
500	*
501	* @return string
502	*/
503	public function get_recipient() {
504	return apply_filters( 'learn-press/email-recipient-' . $this->id, $this->recipient, $this->object );
505	}
506
507	/**
508	* Get email subject.
509	*
510	* @return string
511	*/
512	public function get_subject(): string {
513	return $this->format_string( $this->subject );
514	}
515
516	/**
517	* Get email content.
518	*
519	* @return string
520	* @editor tungnx
521	*/
522	public function get_content(): string {
523	$email_format = $this->get_email_format();
524
525	if ( 'plain' == $email_format ) {
526	$email_content = preg_replace( $this->plain_search, $this->plain_replace, strip_tags( $this->get_content_plain() ) );
527	} elseif ( in_array( $email_format, array( 'html', 'multipart' ) ) ) {
528	$email_content = $this->get_content_html();
529	} else {
530	$email_content = preg_replace( $this->text_search, $this->text_replace, $this->get_content_text_message() );
531	}
532
533	$email_content = $this->format_string( $email_content );
534
535	return wordwrap( $email_content, 70 );
536	}
537
538	/**
539	* Get email heading.
540	*
541	* @return string
542	*/
543	public function get_heading(): string {
544	return $this->format_string( $this->heading );
545	}
546
547	/**
548	* Get email footer text.
549	*
550	* @return string
551	*/
552	public function get_footer_text(): string {
553	$text = LP_Settings::instance()->get( 'emails_general.footer_text', '' );
554
555	return LP_Helper::sanitize_params_submitted( $text, 'html' );
556	}
557
558	/**
559	* Get email content HTML.
560	*
561	* @return string
562	*/
563	public function get_content_html(): string {
564	$template = $this->get_template( 'template_html' );
565	$template_file = $this->template_base . $template;
566	$content = $this->settings->get( 'email_content.html', file_get_contents( $template_file ) );
567
568	return stripslashes( $content );
569	}
570
571	/**
572	* Get email content plain.
573	*
574	* @return string
575	*/
576	public function get_content_plain(): string {
577	$template = $this->get_template( 'template_plain' );
578	$template_file = $this->template_base . $template;
579	$content_tmp = LP_WP_Filesystem::instance()->file_get_contents( $template_file );
580	$content = $this->settings->get( 'email_content.plain', $content_tmp );
581	$content = stripslashes( $content );
582
583	return $content;
584	}
585
586	/**
587	* Get content context message.
588	*
589	* @return string
590	*/
591	public function get_content_text_message(): string {
592	return apply_filters( 'learn-press/email-text-message-' . $this->id, $this->settings->get( 'content_text_message' ) );
593	}
594
595	/**
596	* Get email headers.
597	*
598	* @return string\|array
599	*/
600	public function get_headers() {
601	$headers = [
602	'Content-Type: ' . $this->get_content_format() . "\r\n",
603	];
604
605	$recipients = $this->settings->get( 'recipients', $this->recipients );
606
607	if ( ! empty( $recipients ) ) {
608	$cc_emails = explode( ',', $recipients );
609	foreach ( $cc_emails as $cc_email ) {
610	$headers[] = 'Cc: ' . $cc_email;
611	}
612	}
613
614	return apply_filters( 'learn-press/email-headers', $headers, $this );
615	}
616
617	/**
618	* Get email attachments.
619	*
620	* @return array
621	*/
622	public function get_attachments() {
623	return apply_filters( 'learn-press/email-attachments', array(), $this->id, $this->object );
624	}
625
626	/**
627	* Get FROM address. Default is admin email.
628	*
629	* @return string
630	* @editor tungnx
631	* @version 1.0.1
632	* @editor tungnx
633	* @modify 4.1.4 - comment - not override hook
634	*/
635	/*public function get_from_address(): string {
636	$email = LP_Settings::instance()->get( 'emails_general.from_email', get_option( 'admin_email' ) );
637
638	return sanitize_email( $email );
639	}*/
640
641	/**
642	* Get FROM name. Default is Blog name.
643	*
644	* @return string
645	* @editor tungnx
646	* @version 1.0.1
647	*/
648	public function get_from_name(): string {
649	$name = LP_Settings::instance()->get( 'emails_general.from_name', get_option( 'blogname' ) );
650
651	return LP_Helper::sanitize_params_submitted( $name );
652	}
653
654	/**
655	* Get WP Blog name.
656	*
657	* @return string
658	*/
659	public function get_blogname() {
660	return wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );
661	}
662
663	/**
664	* Get email content format.
665	*
666	* @return string
667	*/
668	public function get_content_format() {
669	switch ( $this->get_email_format() ) {
670	case 'text_message':
671	case 'html':
672	return 'text/html';
673	case 'multipart':
674	return 'multipart/alternative';
675	default:
676	return 'text/plain';
677	}
678	}
679
680	/**
681	* @return string
682	*/
683	public function get_email_format() {
684	return $this->email_format && class_exists( 'DOMDocument' ) ? $this->email_format : 'plain';
685	}
686
687	/**
688	* Apply css from external to inline.
689	*
690	* @param string $content
691	*
692	* @return string
693	*/
694	public function apply_style_inline( $content ): string {
695	try {
696	if ( ! in_array( $this->get_content_format(), array( 'text/html', 'multipart/alternative' ) ) ) {
697	return $content;
698	}
699
700	// Get CSS styles
701	ob_start();
702	learn_press_get_template( 'emails/email-styles.php' );
703	$css = apply_filters( 'learn_press_email_styles', ob_get_clean(), $this->id, $this );
704
705	// Apply CSS styles inline for picky email clients
706	//$content = CssInliner::fromHtml( $content )->inlineCss( $css )->render();
707	$cssToInlineStyles = new CssToInlineStyles();
708	$content = $cssToInlineStyles->convert( $content, $css );
709	} catch ( Exception $e ) {
710
711	}
712
713	return apply_filters( 'learn-press/email-content-inline-style', $content, $this->id );
714	}
715
716	/**
717	* Get template file from type.
718	*
719	* @param string $type
720	*
721	* @return string
722	*/
723	public function get_template( $type ) {
724	$type = esc_attr( basename( $type ) );
725
726	if ( 'template_html' == $type ) {
727	return $this->template_html;
728	} elseif ( 'template_plain' == $type ) {
729	return $this->template_plain;
730	}
731
732	return '';
733	}
734
735	protected function save_template( $code, $path ) {
736	return;
737	}
738
739	/**
740	* Get template file.
741	*
742	* @param string $template
743	* @param string $template_path
744	*
745	* @return string
746	*/
747	public function get_theme_template_file( $template, $template_path = null ) {
748	$template_dir = apply_filters( 'learn-press/template-directory', $template_path ? $template_path : learn_press_template_path(), $template );
749
750	return join(
751	'',
752	array(
753	trailingslashit( get_stylesheet_directory() ),
754	trailingslashit( $template_dir ),
755	$template,
756	)
757	);
758	}
759
760	/**
761	* Send email.
762	*
763	* @param string\|array $to
764	* @param string $subject
765	* @param string $message
766	* @param string\|string[] $headers
767	* @param array $attachments
768	*
769	* @editor tungnx
770	* @return bool
771	* @version 1.0.1
772	*
773	*/
774	public function send( $to, string $subject, string $message, $headers, array $attachments ): bool {
775	$return = false;
776	$message = apply_filters( 'learn-press/email-content', $this->apply_style_inline( $message ), $this );
777
778	if ( is_string( $to ) ) {
779	$to = preg_split( '~\s?,\s?~', $to );
780
781	$return = wp_mail( $to, $subject, $message, $headers, $attachments );
782	} elseif ( is_array( $to ) ) {
783	foreach ( $to as $t ) {
784	$return = wp_mail( $t, $subject, $message, $headers, $attachments );
785	}
786	}
787
788	return $return;
789	}
790
791	/**
792	* Get all values set and send email
793	*
794	* @author tungnx
795	* @since 4.1.3
796	*/
797	public function send_email(): bool {
798	add_filter( 'wp_mail_from_name', array( $this, 'get_from_name' ) );
799	add_filter( 'wp_mail_content_type', array( $this, 'get_content_format' ) );
800
801	return $this->send( $this->get_recipient(), $this->get_subject(), $this->get_content(), $this->get_headers(), $this->get_attachments() );
802	}
803
804	/**
805	* Get common variables.
806	* Variables use for click add to content of Email
807	*
808	* @param string $format
809	*
810	* @return array
811	* @author tungnx
812	* @since 4.1.1
813	*/
814	public function get_common_variables( string $format = 'plain' ): array {
815	$heading = strip_tags( $this->get_heading() );
816	$footer_text = strip_tags( $this->get_footer_text() );
817
818	$header = $heading;
819	$footer = $footer_text;
820
821	if ( $format != 'plain' ) {
822	$header = $this->email_header( $heading );
823	$footer = $this->email_footer( $footer_text );
824	}
825
826	$admin_user = get_user_by( 'email', get_option( 'admin_email' ) );
827
828	return apply_filters(
829	'email_variables_common',
830	[
831	'{{header}}' => $header,
832	'{{footer}}' => $footer,
833	'{{footer_text}}' => $footer_text,
834	'{{site_url}}' => get_home_url(),
835	'{{site_title}}' => $this->get_blogname(),
836	'{{site_admin_email}}' => get_option( 'admin_email' ),
837	'{{site_admin_name}}' => learn_press_get_profile_display_name( $admin_user ),
838	'{{login_url}}' => learn_press_get_login_url(),
839	'{{plain_text}}' => $format == 'plain',
840	]
841	);
842	}
843
844	/**
845	* @param string $name
846	*
847	* @return string
848	*/
849	public function get_field_name( $name ) {
850	return $this->_option_id . "[$name]";
851	}
852
853	/**
854	* Default options for all emails.
855	* Almost the emails are the same with options.
856	*
857	* @return array
858	*/
859	protected function _default_settings(): array {
860	/**
861	* In case the email is not for sending to specific admin (like user who has bought course or author of course, etc..)
862	* So, we do not need this field.
863	*/
864
865	$enable_recipients = $this->enable_recipients;
866
867	$default = array_merge(
868	array(
869	array(
870	'type' => 'title',
871	),
872	array(
873	'title' => esc_html__( 'Enable/Disable', 'learnpress' ),
874	'type' => 'checkbox',
875	'default' => 'no',
876	'id' => $this->get_field_name( 'enable' ),
877	'desc' => $this->description,
878	),
879	),
880	$enable_recipients ? array(
881	array(
882	'title' => esc_html__( 'Recipient(s)', 'learnpress' ),
883	'type' => 'text',
884	'default' => $this->recipients,
885	'id' => $this->get_field_name( 'recipients' ),
886	'desc' => esc_html__( 'Separate other recipients with commas.', 'learnpress' ),
887	),
888	) : array(),
889	array(
890	array(
891	'title' => esc_html__( 'Subject', 'learnpress' ),
892	'type' => 'text',
893	'default' => $this->default_subject,
894	'id' => $this->get_field_name( 'subject' ),
895	'css' => 'width:400px',
896	),
897	array(
898	'title' => esc_html__( 'Email heading', 'learnpress' ),
899	'type' => 'text',
900	'default' => $this->default_heading,
901	'id' => $this->get_field_name( 'heading' ),
902	'css' => 'width:400px',
903	),
904	array(
905	'title' => esc_html__( 'Content', 'learnpress' ),
906	'type' => 'email-content',
907	'default' => '',
908	'id' => $this->get_field_name( 'email_content' ),
909	'template_base' => $this->template_base,
910	'template_path' => $this->template_path,
911	'template_html' => $this->template_html,
912	'template_plain' => $this->template_plain,
913	'template_html_local' => $this->get_theme_template_file( 'html', $this->template_path ),
914	'template_plain_local' => $this->get_theme_template_file( 'plain', $this->template_path ),
915	'support_variables' => $this->get_variables_support(),
916	),
917	array(
918	'type' => 'sectionend',
919	),
920	)
921	);
922
923	return $default;
924	}
925
926	/**
927	* Get settings in admin.
928	*
929	* @return bool\|mixed
930	* @since 3.0.0
931	*
932	*/
933	public function get_settings() {
934	return apply_filters( 'learn-press/email-settings/' . $this->id . '/settings', $this->_default_settings() );
935	}
936
937	/**
938	* Get instructors to send mail.
939	*
940	* @param null $order_id
941	*
942	* @return array
943	* @since 3.0.0
944	*
945	*/
946	public function get_order_instructors( $order_id ) {
947	if ( ! $order_id ) {
948	return array();
949	}
950
951	$order = learn_press_get_order( $order_id );
952
953	$items = $order->get_items();
954	$instructors = array();
955
956	if ( count( $items ) ) {
957	foreach ( $items as $item ) {
958	if ( ! isset( $item['course_id'] ) ) {
959	continue;
960	}
961
962	$user_id = get_post_field( 'post_author', $item['course_id'] );
963	if ( $user_id ) {
964	$instructors[] = $user_id;
965	}
966	}
967	}
968
969	return $instructors;
970	}
971
972	protected function _get_admin_email() {
973	return apply_filters( 'learn-press/email/admin-email', get_option( 'admin_email' ) );
974	}
975
976	/**
977	* @return string
978	*/
979	public function __toString() {
980	return $this->title;
981	}
982
983	/**
984	* Get image header in general settings.
985	*
986	* @return string
987	*/
988	public function get_image_header(): string {
989	$image = LP_Settings::instance()->get( 'emails_general.header_image', '' );
990
991	if ( ! empty( $image ) ) {
992	$image = wp_get_attachment_image_url( $image, 'full' );
993	}
994
995	return $image;
996	}
997
998	/**
999	* Email header.
1000	*
1001	* @param string $heading
1002	*
1003	* @return string
1004	*/
1005	public function email_header( string $heading ): string {
1006	ob_start();
1007	learn_press_get_template(
1008	'emails/email-header.php',
1009	[
1010	'email_heading' => $heading,
1011	'image_header' => $this->get_image_header(),
1012	]
1013	);
1014
1015	return ob_get_clean();
1016	}
1017
1018	/**
1019	* Email footer.
1020	*
1021	* @param string $footer_text
1022	*
1023	* @return string
1024	*/
1025	public function email_footer( string $footer_text ): string {
1026	ob_start();
1027	learn_press_get_template( 'emails/email-footer.php', array( 'footer_text' => $footer_text ) );
1028
1029	return ob_get_clean();
1030	}
1031
1032	/**
1033	* Set receive email
1034	*
1035	* @param string $receive_email
1036	*/
1037	public function set_receive( string $receive_email ) {
1038	$this->recipient = $receive_email;
1039	}
1040
1041	/**
1042	* Method called by background on LP_Background_Single_Email
1043	*
1044	* @param array $params
1045	*
1046	* @see LP_Background_Single_Email::handle()
1047	*
1048	*/
1049	public function handle( array $params ) {
1050	}
1051	}
1052	}
1053