<?php

//
// A simple function to redirect a page while still in the header
//
function redirectPage($page = null) {
   if ( is_null($page) ) $page = "index.php";
   header("Location: {$page}");
   exit();
}

//
// This function outputs the HTML header along with adding a string
// of text to the page title.
//
function includeHTMLHeader($headertext = "", ...$sheets) {
   global $currentuser;
   if ($headertext != "") $fullpagetitle = htmlspecialchars($headertext);
   $extrasheets = "      <!-- Extra CSS included by the current page -->\n";
   foreach ( $sheets as $sheet ) {
      $extrasheets .= "      <link type='text/css' rel='stylesheet' href='css/{$sheet}'/>\n";
   }
   require 'htmlheader.php';
}

//
// This function outputs the HTML header along with adding a string
// of text to the page title. This is for pages without side navigation.
//
function includeHTMLHeaderBasic($headertext = "", ...$sheets) {
   global $currentuser;
   if ($headertext != "") $fullpagetitle = htmlspecialchars($headertext);
   $extrasheets = "      <!-- Extra CSS included by the current page -->\n";
   foreach ( $sheets as $sheet ) {
      $extrasheets .= "      <link type='text/css' rel='stylesheet' href='css/{$sheet}'/>\n";
   }
   require 'htmlheader-basic.php';
}

//
// This function outputs the HTML footer along with adding script tags
// for any script files passed to the function. These files are assumed
// to be in the js/ folder.
//
function includeHTMLFooter(...$scripts) {
   require 'htmlfooter.php';
   foreach ( $scripts as $script ) {
      echo "<script type='text/javascript' src='js/", trim($script), "'></script>\n";
   }
   echo "    </body>\n";
   echo "  </html>\n";
}

//
// This function outputs the HTML footer along with adding script tags
// for any script files passed to the function. These files are assumed
// to be in the js/ folder. This is for pages without side navigation.
//
function includeHTMLFooterBasic(...$scripts) {
   require 'htmlfooter-basic.php';
   foreach ( $scripts as $script ) {
      echo "<script type='text/javascript' src='js/", trim($script), "'></script>\n";
   }
   echo "    </body>\n";
   echo "  </html>\n";
}

function isValidIPAddress($address) {
   $octets = explode(".", $address);
   if ( count($octets) != 4 ) return false;
   foreach ( $octets as $octet ) {
      if ( !is_numeric($octet) || ($octet < 0) || ($octet > 255) ) return false;
   }
   return true;
}