/* CHTTPQ (C/W) CI:A - Certus In Audio [http://certus.in/] */

    /-= CHTTPQ =---------------------------------------------------------------
    |
    | ABOUT
    |
    |     This class implements a simple Javascript HTTP query library.
    |     This allows to make (HTTP and HTTPS) requests, exchange data
    |     with a server, and modify the current page without reloading
    |     it, on an easy way through Javascript. Submitting forms and
    |     retrieving additional content are two common uses. All modern
    |     browsers support the XMLHttpRequest object (IE5 and IE6 use an
    |     ActiveXObject), which is the base object used in this class.
    |
    | ATTRIBUTES/FIELDS
    |
    |     {private}   object    _self
    |     {public}    string    strDebugMessagesContainer
    |     {public}    integer   intState
    |     {public}    integer   intStatus
    |     {public}    array     arrHeaders
    |     {public}    string    strText
    |     {private}   string    _strURL
    |     {private}   array     _arrParameters
    |     {private}   boolean   _bEscapeParameters
    |     {private}   boolean   _bUsePostRequests
    |     {private}   string    _strPostDataContentType
    |     {private}   string    _strCallbackFunction
    |     {private}   object    _objHTTP
    |
    | METHODS
    |
    |     {private}   boolean   _isValidBoolean( boolean )
    |     {private}   boolean   _isValidString( string )
    |     {private}   boolean   _isValidURL( string )
    |     {private}   boolean   _doDM( string )
    |     {public}    boolean   setURL( string )
    |     {public}    string    getURL( void )
    |     {public}    boolean   checkURL( void )
    |     {public}    boolean   addParameter( string , string )
    |     {public}    boolean   setParameter( string , string )
    |     {public}    boolean   deleteParameter( string )
    |     {public}    boolean   hasParameter( string )
    |     {public}    array     listParameters( void )
    |     {public}    integer   countParameters( void )
    |     {public}    string    getParameter( string )
    |     {public}    boolean   setEscapeParameters( boolean )
    |     {public}    boolean   getEscapeParameters( void )
    |     {public}    boolean   setUsePostRequests( boolean )
    |     {public}    boolean   getUsePostRequests( void )
    |     {public}    boolean   setPostDataContentType( string )
    |     {public}    string    getPostDataContentType( void )
    |     {public}    boolean   setCallbackFunction( string )
    |     {public}    string    getCallbackFunction( void )
    |     {public}    boolean   doQuery( void )
    |
    | USAGE
    |
    |     First of all, including this class file would be a good idea.
    |     The easiest way to do this is to place the following code into
    |     the HEAD-section of a HTML document:
    |         <script src="./chttpq.js"></script>
    |
    |     The next step is to create an object instance of type CHTTPQ, like:
    |         objQ = new CHTTPQ();
    |
    |     After doing this, there are only two tasks left, in fact; these
    |     are: set up an URL for a request and define a response-handler-
    |     function. This function will be called after receiving a response
    |     from a server. Note: this can be several times. The CHTTPQ class
    |     serves four public fields (variables), which allows to determine
    |     the current state of a query, HTTP status, HTTP headers and response
    |     text. These variables are:
    |         - intState .... : 1=open , 2=sent , 3=receiving , 4=loaded
    |         - intStatus ... : HTTP status code
    |         - arrHeaders .. : HTTP headers
    |         - strText ..... : response text
    |
    |     The following lines demonstrate how to define and implement a
    |     response-handler-function:
    |         function handleResponse() { document.status = objQ.intState; }
    |         objQ.setCallbackFunction( "handleResponse" );
    |
    |     Set up an URL for a request and do a query; example:
    |         objQ.setURL( document.location.toString() );
    |         objQ.doQuery();
    |
    | EXAMPLE
    |
    |     <html>
    |         <head>
    |             <title>Example</title>
    |             <script src="./chttpq.js"></script>
    |             <script>
    |             <!--//
    |             function handleResponse()
    |             {
    |                 if( ( objQ.intState == 4 ) && ( objQ.intStatus == 200 ) )
    |                 {
    |                     var objR = document.getElementById( 'response' );
    |                     objR.value = objQ.arrHeaders + "\n" + objQ.strText;
    |                 }
    |             }
    |             objQ = new CHTTPQ();
    |             objQ.setCallbackFunction( "handleResponse" );
    |             objQ.setURL( document.location.toString() );
    |             window.onload = objQ.doQuery();
    |             //-->
    |             </script>
    |         </head>
    |         <body>
    |             <textarea id="response" cols="80" rows="25"></textarea>
    |         </body>
    |     </html>
    |
    \--------------------------------------------------------------------------


<?php
if( count( $_REQUEST ) > 0 )
{
    header( "Content-Type: text/plain" );
    echo "Parameter send method = " .
         ( ( count( $_GET ) > 0 ) ? "GET" : "POST" ) . "\n" .
         str_ireplace( "array" , "Parameters:" , print_r( $_REQUEST , true ) );
    exit;
}
?>
<html>
    <head>
        <title>CHTTPQ Demo</title>
        <script src="./chttpq.js"></script>
        <script>
        <!--//
        var objQ = null;
        function initQ()
        {
            objQ = new CHTTPQ();
            objQ.strDebugMessagesContainer = "dbgmsg";
            objQ.setCallbackFunction( "handleResponse" );
            objQ.setPostDataContentType( "application/x-www-form-urlencoded" );
            objQ.setURL( document.location.toString() );
            return true;
        }
        function updateFormFields()
        {
            document.getElementById( 'url' ).value = objQ.getURL();
            var arrParams = objQ.listParameters();
            var intParamCount = objQ.countParameters();
            var objPFO = document.getElementById( 'parameter' );
            objPFO.options.length = 0;
            for( var i = 0 ; i <= intParamCount - 1 ; i++ )
            {
                objPFO[ objPFO.length ] = new Option( arrParams[ i ] );
            }
            var bEP = objQ.getEscapeParameters();
            document.getElementById( 'escapeparameters' ).checked = bEP;
            var bUP = objQ.getUsePostRequests();
            document.getElementById( 'usepostrequests' ).checked = bUP;
            return true;
        }
        function addParameter()
        {
            var objPFO = document.getElementById( 'parameter' );
            var strKey = prompt( "Parameter name (key):" );
            if( ( typeof strKey != 'string' ) || ( strKey.length < 1 ) )
            {
                return false;
            }
            if( objQ.hasParameter( strKey ) )
            {
                if( confirm( "Parameter '" +
                             strKey +
                             "' exists. Set new value?" ) )
                {
                    var strValue = prompt( "Parameter value:" ,
                                           objQ.getParameter( strKey ) );
                    if( typeof strValue != 'string' )
                    {
                        return false;
                    }
                    objQ.setParameter( strKey , strValue );
                }
                else
                {
                    return false;
                }
            }
            else
            {
                var strValue = prompt( "Parameter value:" );
                if( typeof strValue != 'string' )
                {
                    return false;
                }
                objQ.addParameter( strKey , strValue );
            }
            updateFormFields();
            return true;
        }
        function editParameter()
        {
            var objPFO = document.getElementById( 'parameter' );
            if( objPFO.length < 1 )
            {
                return false;
            }
            var strKey = objPFO[ objPFO.selectedIndex ].value;
            if( !objQ.hasParameter( strKey ) )
            {
                alert( "Parameter '" + strKey + "' does not exist." );
                return false;
            }
            var strValue = prompt( "New parameter value:" ,
                                   objQ.getParameter( strKey ) );
            if( typeof strValue != 'string' )
            {
                return false;
            }
            objQ.setParameter( strKey , strValue );
            updateFormFields();
            return true;
        }
        function removeParameter()
        {
            var objPFO = document.getElementById( 'parameter' );
            if( objPFO.length < 1 )
            {
                return false;
            }
            var strKey = objPFO[ objPFO.selectedIndex ].value;
            if( !objQ.hasParameter( strKey ) )
            {
                alert( "Parameter '" + strKey + "' does not exist." );
                return false;
            }
            if( !confirm( "Really delete parameter '" + strKey + "'?" ) )
            {
                return false;
            }
            objQ.deleteParameter( strKey );
            updateFormFields();
            return true;
        }
        function clearDebugMessages()
        {
            document.getElementById( 'dbgmsg' ).value = "";
            return true;
        }
        function clearResults()
        {
            document.getElementById( 'results' ).value = "";
            return true;
        }
        function doQuery()
        {
            objQ.setURL( document.getElementById( 'url' ).value );
            if( !objQ.checkURL() )
            {
                alert( "Invalid URL! Abort." );
                return false;
            }
            var strC1 = objQ.getPostDataContentType();
            var strC2 = objQ.getCallbackFunction();
            if( ( strC1 != 'application/x-www-form-urlencoded' ) ||
                ( strC2 != 'handleResponse' ) )
            {
                alert( "Invalid settings! Abort." );
                return false;
            }
            objQ.doQuery();
            return true;
        }
        function handleResponse()
        {
            var oR = document.getElementById( 'results' );
            oR.value = "READY STATE ... : " + objQ.intState + "\n\n" +
                       "HTTP STATUS ... : " + objQ.intStatus + "\n\n" +
                       "HTTP HEADERS .. : (->)\n    " +
                       objQ.arrHeaders.replace( /\n/g , "\n    " ) +
                       "\nRESPONSE ...... : (->)\n    " +
                       objQ.strText.replace( /\n/g , "\n    " );
            return true;
        }
        //-->
        </script>
    </head>
    <body>
        <table border="0" width="100%">
            <tr><th colspan="2">CHTTPQ Demo</th></tr>
            <tr><td colspan="2">&nbsp;</td></tr>
            <tr>
                <td><label for="url">URL:</label></td>
                <td><input type="text" id="url" style="width:100%;"></td>
            </tr>
            <tr>
                <td><label for="parameter">Parameter:</label></td>
                <td>
                    <select id="parameter" style="width:100%;"></select><br>
                    <input type="button"
                           value="Add"
                           onclick="addParameter();">
                    <input type="button"
                           value="Edit"
                           onclick="editParameter();">
                    <input type="button"
                           value="Remove"
                           onclick="removeParameter();">
                    <input type="checkbox"
                           id="escapeparameters"
                           onclick="objQ.setEscapeParameters(this.checked);">
                    <label for="escapeparameters">escape parameters</label>
                    <input type="checkbox"
                           id="usepostrequests"
                           onclick="objQ.setUsePostRequests(this.checked);">
                    <label for="usepostrequests">use post requests</label>
                </td>
            </tr>
            <tr>
                <td><label>Options:</label></td>
                <td>
                    <input type="button"
                           value="Query"
                           onclick="doQuery();">
                    <input type="button"
                           value="Reset"
                           onclick="initQ(); updateFormFields();">
                </td>
            </tr>
        </table>
        <table border="0" width="100%"><tr>
            <td width="50%">
                <br><label for="dbgmsg">Debug messages:</label><br>
                <textarea id="dbgmsg"
                          cols="80"
                          rows="10"
                          style="width:100%;"
                          wrap="off"></textarea>
                <br><input type="button"
                           value="Clear"
                           onclick="clearDebugMessages();">
            </td>
            <td width="50%">
                <br><label for="results">Query results:</label><br>
                <textarea id="results"
                          cols="80"
                          rows="10"
                          style="width:100%;"
                          wrap="off"></textarea>
                <br><input type="button"
                           value="Clear"
                           onclick="clearResults();">
            </td>
        </tr></table>
        <script>
        <!--//
        initQ();
        updateFormFields();
        //-->
        </script>
    </body>
</html>