<?php
/**
 * @file src/Protocol/Email.php
 */
namespace Friendica\Protocol;

require_once 'include/html2plain.php';
require_once 'include/msgclean.php';
require_once 'include/quoteconvert.php';

/**
 * @brief Email class
 */
class Email
{
	/**
	 * @param string $mailbox  The mailbox name
	 * @param string $username The username
	 * @param string $password The password
	 * @return object
	 */
	public static function emailConnect($mailbox, $username, $password)
	{
		if (! function_exists('imap_open')) {
			return false;
		}

		$mbox = @imap_open($mailbox, $username, $password);

		return $mbox;
	}

	/**
	 * @param object $mbox       mailbox
	 * @param string $email_addr email
	 * @return array
	 */
	public static function emailPoll($mbox, $email_addr)
	{
		if (! ($mbox && $email_addr))
			return array();

		$search1 = @imap_search($mbox, 'FROM "' . $email_addr . '"', SE_UID);
		if (!$search1) {
			$search1 = array();
		} else {
			logger("Found mails from ".$email_addr, LOGGER_DEBUG);
		}

		$search2 = @imap_search($mbox, 'TO "' . $email_addr . '"', SE_UID);
		if (!$search2) {
			$search2 = array();
		} else {
			logger("Found mails to ".$email_addr, LOGGER_DEBUG);
		}

		$search3 = @imap_search($mbox, 'CC "' . $email_addr . '"', SE_UID);
		if (!$search3) {
			$search3 = array();
		} else {
			logger("Found mails cc ".$email_addr, LOGGER_DEBUG);
		}

		$res = array_unique(array_merge($search1, $search2, $search3));

		return $res;
	}

	/**
	 * @param array $mailacct mail account
	 * @return object
	 */
	public static function constructMailboxName($mailacct)
	{
		$ret = '{' . $mailacct['server'] . ((intval($mailacct['port'])) ? ':' . $mailacct['port'] : '');
		$ret .= (($mailacct['ssltype']) ?  '/' . $mailacct['ssltype'] . '/novalidate-cert' : '');
		$ret .= '}' . $mailacct['mailbox'];
		return $ret;
	}

	/**
	 * @param object  $mbox mailbox
	 * @param integer $uid  user id
	 * @return mixed
	 */
	public static function emailMsgMeta($mbox, $uid)
	{
		$ret = (($mbox && $uid) ? @imap_fetch_overview($mbox, $uid, FT_UID) : array(array())); // POSSIBLE CLEANUP --> array(array()) is probably redundant now
		return (count($ret)) ? $ret : array();
	}

	/**
	 * @brief Check addons, not called from main friendica project
	 * I don't see it in addons either
	 */
	function email_msg_headers($mbox, $uid) {
		$raw_header = (($mbox && $uid) ? @imap_fetchheader($mbox,$uid,FT_UID) : '');
		$raw_header = str_replace("\r",'',$raw_header);
		$ret = array();
		$h = explode("\n",$raw_header);
		if (count($h))
		foreach ($h as $line ) {
			if (preg_match("/^[a-zA-Z]/", $line)) {
				$key = substr($line,0,strpos($line,':'));
				$value = substr($line,strpos($line,':')+1);

				$last_entry = strtolower($key);
				$ret[$last_entry] = trim($value);
			}
			else {
				$ret[$last_entry] .= ' ' . trim($line);
			}
		}
		return $ret;
	}

	/**
	 * @param object  $mbox  mailbox
	 * @param integer $uid   user id
	 * @param string  $reply reply
	 * @return array
	 */
	public static function emailGetMsg($mbox, $uid, $reply)
	{
		$ret = array();

		$struc = (($mbox && $uid) ? @imap_fetchstructure($mbox, $uid, FT_UID) : null);

		if (! $struc) {
			return $ret;
		}

		if (! $struc->parts) {
			$ret['body'] = self::emailGetPart($mbox, $uid, $struc, 0, 'html');
			$html = $ret['body'];

			if (trim($ret['body']) == '') {
				$ret['body'] = self::emailGetPart($mbox, $uid, $struc, 0, 'plain');
			} else {
				$ret['body'] = html2bbcode($ret['body']);
			}
		} else {
			$text = '';
			$html = '';
			foreach ($struc->parts as $ptop => $p) {
				$x = self::emailGetPart($mbox, $uid, $p, $ptop + 1, 'plain');
				if ($x) {
					$text .= $x;
				}

				$x = self::emailGetPart($mbox, $uid, $p, $ptop + 1, 'html');
				if ($x) {
					$html .= $x;
				}
			}
			if (trim($html) != '') {
				$ret['body'] = html2bbcode($html);
			} else {
				$ret['body'] = $text;
			}
		}

		$ret['body'] = removegpg($ret['body']);
		$msg = removesig($ret['body']);
		$ret['body'] = $msg['body'];
		$ret['body'] = convertquote($ret['body'], $reply);

		if (trim($html) != '') {
			$ret['body'] = removelinebreak($ret['body']);
		}

		$ret['body'] = unifyattributionline($ret['body']);

		return $ret;
	}

	// At the moment - only return plain/text.
	// Later we'll repackage inline images as data url's and make the HTML safe
	/**
	 * @param object  $mbox    mailbox
	 * @param integer $uid     user id
	 * @param object  $p       parts
	 * @param integer $partno  part number
	 * @param string  $subtype sub type
	 * @return string
	 */
	private static function emailGetPart($mbox, $uid, $p, $partno, $subtype)
	{
		// $partno = '1', '2', '2.1', '2.1.3', etc for multipart, 0 if simple
		global $htmlmsg,$plainmsg,$charset,$attachments;

		//echo $partno."\n";

		// DECODE DATA
		$data = ($partno)
			? @imap_fetchbody($mbox, $uid, $partno, FT_UID|FT_PEEK)
		: @imap_body($mbox, $uid, FT_UID|FT_PEEK);

		// Any part may be encoded, even plain text messages, so check everything.
		if ($p->encoding==4) {
			$data = quoted_printable_decode($data);
		} elseif ($p->encoding==3) {
			$data = base64_decode($data);
		}

		// PARAMETERS
		// get all parameters, like charset, filenames of attachments, etc.
		$params = array();
		if ($p->parameters) {
			foreach ($p->parameters as $x) {
				$params[strtolower($x->attribute)] = $x->value;
			}
		}

		if (isset($p->dparameters) && $p->dparameters) {
			foreach ($p->dparameters as $x) {
				$params[strtolower($x->attribute)] = $x->value;
			}
		}

		// ATTACHMENT
		// Any part with a filename is an attachment,
		// so an attached text file (type 0) is not mistaken as the message.

		if ((isset($params['filename']) && $params['filename']) || (isset($params['name']) && $params['name'])) {
			// filename may be given as 'Filename' or 'Name' or both
			$filename = ($params['filename'])? $params['filename'] : $params['name'];
			// filename may be encoded, so see imap_mime_header_decode()
			$attachments[$filename] = $data;  // this is a problem if two files have same name
		}

		// TEXT
		if ($p->type == 0 && $data) {
			// Messages may be split in different parts because of inline attachments,
			// so append parts together with blank row.
			if (strtolower($p->subtype)==$subtype) {
				$data = iconv($params['charset'], 'UTF-8//IGNORE', $data);
				return (trim($data) ."\n\n");
			} else {
				$data = '';
			}

			// $htmlmsg .= $data ."<br><br>";
			$charset = $params['charset'];  // assume all parts are same charset
		}

		// EMBEDDED MESSAGE
		// Many bounce notifications embed the original message as type 2,
		// but AOL uses type 1 (multipart), which is not handled here.
		// There are no PHP functions to parse embedded messages,
		// so this just appends the raw source to the main message.
		//	elseif ($p->type==2 && $data) {
		//		$plainmsg .= $data."\n\n";
		//	}

		// SUBPART RECURSION
		if (isset($p->parts) && $p->parts) {
			$x = "";
			foreach ($p->parts as $partno0 => $p2) {
				$x .=  self::emailGetPart($mbox, $uid, $p2, $partno . '.' . ($partno0+1), $subtype);  // 1.2, 1.2.1, etc.
				//if ($x) {
				//	return $x;
				//}
			}
			return $x;
		}
	}

	/**
	 * @param string $in_str  in string
	 * @param string $charset character set
	 * @return string
	 */
	public static function emailHeaderEncode($in_str, $charset)
	{
		$out_str = $in_str;
		$need_to_convert = false;

		for ($x = 0; $x < strlen($in_str); $x ++) {
			if ((ord($in_str[$x]) == 0) || ((ord($in_str[$x]) > 128))) {
				$need_to_convert = true;
			}
		}

		if (! $need_to_convert) {
			return $in_str;
		}

		if ($out_str && $charset) {
			// define start delimimter, end delimiter and spacer
			$end = "?=";
			$start = "=?" . $charset . "?B?";
			$spacer = $end . "\r\n " . $start;

			// determine length of encoded text within chunks
			// and ensure length is even
			$length = 75 - strlen($start) - strlen($end);

			/*
				[EDIT BY danbrown AT php DOT net: The following
				is a bugfix provided by (gardan AT gmx DOT de)
				on 31-MAR-2005 with the following note:
				"This means: $length should not be even,
				but divisible by 4. The reason is that in
				base64-encoding 3 8-bit-chars are represented
				by 4 6-bit-chars. These 4 chars must not be
				split between two encoded words, according
				to RFC-2047.
			*/
			$length = $length - ($length % 4);

			// encode the string and split it into chunks
			// with spacers after each chunk
			$out_str = base64_encode($out_str);
			$out_str = chunk_split($out_str, $length, $spacer);

			// remove trailing spacer and
			// add start and end delimiters
			$spacer = preg_quote($spacer, '/');
			$out_str = preg_replace("/" . $spacer . "$/", "", $out_str);
			$out_str = $start . $out_str . $end;
		}
		return $out_str;
	}

	/**
	 * Function emailSend is used by NETWORK_EMAIL and NETWORK_EMAIL2 code
	 * (not to notify the user, but to send items to email contacts)
	 *
	 * @param string $addr    address
	 * @param string $subject subject
	 * @param string $headers headers
	 * @param array  $item    item
	 *
	 * @return void
	 *
	 * @todo This could be changed to use the Emailer class
	 */
	public static function emailSend($addr, $subject, $headers, $item)
	{
		//$headers .= 'MIME-Version: 1.0' . "\n";
		//$headers .= 'Content-Type: text/html; charset=UTF-8' . "\n";
		//$headers .= 'Content-Type: text/plain; charset=UTF-8' . "\n";
		//$headers .= 'Content-Transfer-Encoding: 8bit' . "\n\n";

		$part = uniqid("", true);

		$html    = prepare_body($item);

		$headers .= "Mime-Version: 1.0\n";
		$headers .= 'Content-Type: multipart/alternative; boundary="=_'.$part.'"'."\n\n";

		$body = "\n--=_".$part."\n";
		$body .= "Content-Transfer-Encoding: 8bit\n";
		$body .= "Content-Type: text/plain; charset=utf-8; format=flowed\n\n";

		$body .= html2plain($html)."\n";

		$body .= "--=_".$part."\n";
		$body .= "Content-Transfer-Encoding: 8bit\n";
		$body .= "Content-Type: text/html; charset=utf-8\n\n";

		$body .= '<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">'.$html."</body></html>\n";

		$body .= "--=_".$part."--";

		//$message = '<html><body>' . $html . '</body></html>';
		//$message = html2plain($html);
		logger('notifier: email delivery to ' . $addr);
		mail($addr, $subject, $body, $headers);
	}

	/**
	 * @param string $iri string
	 * @return string
	 */
	public static function iri2msgid($iri)
	{
		if (!strpos($iri, "@")) {
			$msgid = preg_replace("/urn:(\S+):(\S+)\.(\S+):(\d+):(\S+)/i", "urn!$1!$4!$5@$2.$3", $iri);
		} else {
			$msgid = $iri;
		}

		return($msgid);
	}

	/**
	 * @param string $msgid msgid
	 * @return string
	 */
	public static function msgid2iri($msgid)
	{
		if (strpos($msgid, "@")) {
			$iri = preg_replace("/urn!(\S+)!(\d+)!(\S+)@(\S+)\.(\S+)/i", "urn:$1:$4.$5:$2:$3", $msgid);
		} else {
			$iri = $msgid;
		}
		
		return($iri);
	}
}