<?php

	$IMG_SIZE_PREVIEW = 600;
	$IMG_SIZE_MINIATURE = 200;

	/****************************************************
	* This function is called from almost everywhere at *
	* the beggining of the page. It initializes the     *
	* session variables, connect to the db, enabling    *
	* the variable $con for futher use everywhere in    *
	* the php code, and populates the arrays $user      *
	* and $permission, with info about the user.        *
	* @params:                                          *
	*    mode: (string) Indicates required permissions  *
	*          on database. 'ro' gives read             *
	*          permissions, and 'rw' read and write     *
	*          permissions. Other values will result in *
	*          errors.                                  *
	* @return: (db connection): The connection handler. *
	****************************************************/
	function startdb($mode = 'ro'){
		//Include the db configuration file. It's somehow like this
		/*
		<?php
			$host = 'XXXX';
			$db_name = 'XXXX';
			$username_ro = 'XXXX';
			$username_rw = 'XXXX';
			$pass_ro = 'XXXX';
			$pass_rw = 'XXXX';
		?>
		*/
		include('.htpasswd');
		
		//Connect to to database
		if ($mode == 'ro')
			$con = mysqli_connect($host, $username_ro, $pass_ro, $db_name);
		else if ($mode == 'rw')
			$con = mysqli_connect($host, $username_rw, $pass_rw, $db_name);
			
		// Check connection
		if (mysqli_connect_errno()){
			error_log("Failed to connect to database: " . mysqli_connect_error());
			return -1;
		}
		
		//Set encoding options
		mysqli_set_charset($con, 'utf-8');
		header('Content-Type: text/html; charset=utf8');
		mysqli_query($con, 'SET NAMES utf8;');
		
		//Return the db connection
		return $con;
	}
	
	
	/****************************************************
	* This function turns a date string into a human    *
	* readable string, deppending o the specified       * 
	* language.                                         *
	* @params:                                          *
	*    strdate: (string): Date string.                *
	*    lang: (string): Language code (es, en, eu).    *
	*    http_accept_language: (string) Raw header with *
	*                          info about client        *
	*                          language preferences.    *
	*    time: (boolean): Append the time at the end.   *
	* @return: (string array) List of the languages     *
	*          offered, sorted by prefference.          *
	****************************************************/	
	function formatDate($strdate, $lang, $time = true){
		$date = strtotime($strdate);
		$year = date('o', $date);
		$month = date('n', $date);
		$month --;
		$day = date('j', $date);
		$wday = date('N', $date);
		$wday --;
		$hour = date('H', $date);
		$minute = date('i', $date);
		switch ($lang){
			case 'en':
				$week = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'];
				$months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
				if ($time){
					$str = "$week[$wday], $months[$month] $day, $year at $hour:$minute";
				}
				else{
					$str = "$week[$wday], $months[$month] $day, $year";
				}
				break;
			case 'eu':
				$week = ['astelehena', 'asteartea', 'asteazkena', 'osteguna', 'ostirala', 'larumbata', 'igandea'];
				$months = ['urtarrilaren', 'otsailaren', 'martxoaren', 'apirilaren', 'maiatzaren', 'ekainaren', 'uztailaren', 'abuztuaren', 'irailaren', 'urriaren', 'azaroaren', 'abenduaren'];
				if ($time){
					$str = $year . "ko $months[$month] $day" . "an, $week[$wday], $hour:$minute";
				}
				else{
					$str = $year . "ko $months[$month] $day" . "an, $week[$wday]";
				}
				break;
			default:
				$week = ['Lunes', 'Martes', 'Mi&eacute;rcoles', 'Jueves', 'Viernes', 'S&aacute;bado', 'Domingo'];
				$months = ['enero', ' febrero', 'marzo', 'abril', 'mayo', 'junio', 'julio', 'agosto', 'septiembre', 'octubre', 'noviembre', 'diciembre'];
				if ($time){
					$str = "$week[$wday] $day de $months[$month] de $year a las $hour:$minute";
				}
				else{
					$str = "$week[$wday] $day de $months[$month] de $year";
				}
		}
		return $str;
	}
	
	/****************************************************
	* This function turns a date string into a human    *
	* readable string, deppending o the specified       * 
	* language. It is designed to be used for festival  *
	* days only, since it doesnt return the weekday.    *
	* @params:                                          *
	*    strdate: (string): Date string.                *
	*    lang: (string): Language code (es, en, eu).    *
	*    http_accept_language: (string) Raw header with *
	*                          info about client        *
	*                          language preferences.    *
	* @return: (string array) List of the languages     *
	*          offered, sorted by prefference.          *
	****************************************************/	
	function formatFestivalDate($strdate, $lang){
		$date = strtotime($strdate);
		$month = date('n', $date);
		$month --;
		$day = date('j', $date);
		switch ($lang){
			case 'en':
				$months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
				$str = "$months[$month] $day";
				break;
			case 'eu':
				$months = ['urtarrilaren', 'otsailaren', 'martxoaren', 'apirilaren', 'maiatzaren', 'ekainaren', 'uztailaren', 'abuztuaren', 'irailaren', 'urriaren', 'azaroaren', 'abenduaren'];
				$str = "$months[$month] $day";
				break;
			default:
				$months = ['enero', ' febrero', 'marzo', 'abril', 'mayo', 'junio', 'julio', 'agosto', 'septiembre', 'octubre', 'noviembre', 'diciembre'];
				$str = "$day de $months[$month]";
		}
		return $str;
	}
	
	/****************************************************
	* This function closes all the opened HTML tags in  *
	* a given string.                                   * 
	*                                                   *
	* @params:                                          *
	*    html: (string): The string with HTML tags      *
 	****************************************************/
	function closeTags($html) {
		preg_match_all('#<(?!meta|img|br|hr|input\b)\b([a-z]+)(?: .*)?(?<![/|/ ])>#iU', $html, $result);
		$openedtags = $result[1];
		preg_match_all('#</([a-z]+)>#iU', $html, $result);
		$closedtags = $result[1];
		$len_opened = count($openedtags);
		if (count($closedtags) == $len_opened) {
			return $html;
		}
		$openedtags = array_reverse($openedtags);
		for ($i=0; $i < $len_opened; $i++) {
			if (!in_array($openedtags[$i], $closedtags)) {
				$html .= '</'.$openedtags[$i].'>';
			} else {
				unset($closedtags[array_search($openedtags[$i], $closedtags)]);
			}
		}
		return $html;
	} 
	
	/****************************************************
	* Text shortener. Given a string, it trims in the   *
	* proximity of the desired streng, ut to the next   * 
	* white character. If indicated, it will append a   *
	* link to the full text.                            *
	*                                                   *
	* @params:                                          *
	*    text: (string): The text to shorten.           *
	*    length: (int): The desired length.             *
	*    linktext: (string): Text fot the link.         *
	*    link: (string): URI of the full text.          *
 	****************************************************/
 	function cutText($text, $length, $linktext, $link){
		if (strlen($text) < $length){
			return $text;
		}
		$cut = substr($text, 0, strpos($text, " ", $length));
		$cut = closeTags($cut);
		if (strlen($cut) == 0){
			$cut = $text;
		}
		if (strlen($text) != strlen($cut)){
			$cut = $cut . "... <a href='$link'>$linktext</a>";
		}
		return $cut;
	}
	
	/****************************************************
	* Generates a URL-valid string from a regular one.  *
	*                                                   *
	* @params:                                          *
	*    text: (string): Original string.               *
	* @return: (string): URL-valid string.              *
	****************************************************/
	function permalink($text){
		$unwanted_array = array('Š'=>'S', 'š'=>'s', 'Ž'=>'Z', 'ž'=>'z', 'À'=>'A', 'Á'=>'A', 'Â'=>'A', 'Ã'=>'A', 'Ä'=>'A', 'Å'=>'A', 'Æ'=>'A', 'Ç'=>'C', 'È'=>'E', 'É'=>'E',
							'Ê'=>'E', 'Ë'=>'E', 'Ì'=>'I', 'Í'=>'I', 'Î'=>'I', 'Ï'=>'I', 'Ñ'=>'N', 'Ò'=>'O', 'Ó'=>'O', 'Ô'=>'O', 'Õ'=>'O', 'Ö'=>'O', 'Ø'=>'O', 'Ù'=>'U',
							'Ú'=>'U', 'Û'=>'U', 'Ü'=>'U', 'Ý'=>'Y', 'Þ'=>'B', 'ß'=>'Ss', 'à'=>'a', 'á'=>'a', 'â'=>'a', 'ã'=>'a', 'ä'=>'a', 'å'=>'a', 'æ'=>'a', 'ç'=>'c',
							'è'=>'e', 'é'=>'e', 'ê'=>'e', 'ë'=>'e', 'ì'=>'i', 'í'=>'i', 'î'=>'i', 'ï'=>'i', 'ð'=>'o', 'ñ'=>'n', 'ò'=>'o', 'ó'=>'o', 'ô'=>'o', 'õ'=>'o',
							'ö'=>'o', 'ø'=>'o', 'ù'=>'u', 'ú'=>'u', 'û'=>'u', 'ý'=>'y', 'þ'=>'b', 'ÿ'=>'y' );
		$str = strtr( $text, $unwanted_array );
		$str = preg_replace('/[^\da-zA-Z ]/i', '', $str);
		$str = str_replace(' ', '-', $str);
		return $str;
	}
	
	function login($con, $user, $pass){
		session_start();
		$q = mysqli_query($con,"SELECT id, md5(salt) AS s, username FROM user WHERE (lower(username) = lower('$user') OR lower(email) = lower('$user')) AND password = md5('$pass');");
		if (mysqli_num_rows($q) == 1){
			$r = mysqli_fetch_array($q);
			$_SESSION['id'] = $r['id'];
			$_SESSION['salt'] = $r['s'];
			$_SESSION['name'] = $r['username'];
			return true;
		}
		else{
			error_log("Invalid login. username = $_SESSION[name], id = $_SESSION[id]");
			return false;
		}
	}
	
	function checkSession($con){
		session_start(['cookie_lifetime' => 1800,]);
		$qr = mysqli_query($con, "SELECT id FROM user WHERE id = '$_SESSION[id]' AND md5(salt) = '$_SESSION[salt]';");
		//error_log("SELECT id FROM user WHERE id = '$_SESSION[id]' AND md5(salt) = '$_SESSION[salt]';");
		if (mysqli_num_rows($qr) == 1)
			return true;
		else{
			return false;
			error_log("Invalid session. username = $_SESSION[name], id = $_SESSION[id]");
		}
	}
	

	/****************************************************
	* Increases version value in table settings by one. *
	* Helpfull for the app to know when to perform a    * 
	* full sync. Must be called after every INSERT,     *
	* UPDATE or DELETE query to the database.           *
 	****************************************************/
	function version(){
		$con = startdb('rw');
		mysqli_query($con, 'UPDATE settings SET value = value + 1 WHERE name = "version";');
	}
?>
	
