// scripts for hot key navigation

var lastTarget = null;
var defaultTargetBackground = '#FFFFDD';
var defaultTargetBorder = '1px solid #FFFFDD';
var sectionTag = "Section";
var targetTag = "Target";



// navigate by section on a webpage

function FindNext( tag )
{
        var element = null;
        var i = 0;
        var focused = false;
        var first = -1;

        while( i < document.all.length &&  element == null )
        {
                if( document.all[i].id.match( tag  ) )
                {
                        if( first < 0 ) first = i;
                        if( focused ) element = document.all[i];
                }
                if( document.all[i] == document.activeElement )  focused = true;
                i++;
        }

        if( ! element )   element = document.all[  first  ];
        var num =  parseInt(  element.id.substring(  tag.length )  );

        return(  num  );
}

function FindPrev( tag )
{
        var element = null;
        var i = document.all.length;
        var focused = false;
        var last = -1;

        while( i > 0  &&  element == null )
        {
                i--;
                if( document.all[i].id.match( tag ) )
                {
                        if( last < 0 ) last = i;
                        if( focused ) element = document.all[i];
                }
                if( document.all[i] == document.activeElement )  focused = true;
        }

        if( ! element )  element = document.all[  last  ];
        var num =  parseInt(  element.id.substring( tag.length )  );

        return(  num   );
}

function FocusSection( num )
{
        if( lastTarget ) HideTableTarget( lastTarget );

        section = ( num < 0 ? 0 : num );
//      document.location.hash = sectionTag + section;
        document.getElementById(  sectionTag + section ).focus();
}

function NextSection()
{
        var num = FindNext( sectionTag );
        FocusSection(  num   );
}

function PrevSection()
{
        var num =  FindPrev( sectionTag );
        FocusSection(  num   );
}




function HiliteTableTarget ( obj )     // hilite table or parent table
{ 
        if( lastTarget ) HideTableTarget( lastTarget );
        lastTarget = obj;

        var tbl = getTable( obj );

        tbl.style.borderColor = '#E0E0E0 #404040 #404040 #E0E0E0'; //3d appearance
        tbl.style.borderStyle = 'solid';
        tbl.style.borderWidth = '1px';

        tbl.style.background ='#D0D0B0'; 

        SetPointer( tbl  );

}

function HideTableTarget ( obj  ) 
{ 
        var bgcolour = null;
        var tbl = getTable( obj );
        var parent =  tbl.parentNode;

        tbl.style.background = parent.style.background;
        tbl.style.borderColor =  parent.style.background;

         ResetPointer( tbl );
} 


function FocusTarget( num )
{
        var target = ( num < 0 ? 0 : num );
//      document.location.hash = targetTag + target;
        document.getElementById(  targetTag  + target  ).focus();
}


function NextTarget()
{
        var num = FindNext( targetTag );
        FocusTarget(  num   );
}

function PrevTarget()
{
        var num =  FindPrev(  targetTag );
        FocusTarget(  num   );
}


function ProcessKeystroke( e )
{
        var state = true;
        //alert("keystroke");

        var eventMsg =  ( window.event ? event : e );

        var code =  eventMsg.keyCode;
        if( eventMsg.altKey && eventMsg.ctrlKey )
        {
                switch( code  )
                {
                        case 37:        // - Left arrow
                        case 38:        // - UP arrow
                                PrevTarget();
                                state = false; 
                        break;

                        case 39:        // - Right arrow
                        case 40:        // - Down arrow
                                NextTarget();     
                                state = false; 
                        break;

                        case 9: // - tab 
                                if( eventMsg.shiftKey )
                                        PrevTarget();
                                else
                                        NextTarget();
                                state = false;
                        break;

                        case 67:        // C
                        case 88:        // X
                                sendToClipboard( " " + document.getElementById(  "Target" + target)  );
                                state = false; 
                        break;

												case 188:  //ctrl alt ,
                                if( eventMsg.shiftKey )
                                        PrevSection();
                                else
                                        NextSection();
                                state = false;
												break;
												case 190: // ctrl alt .
                                if( eventMsg.shiftKey )
                                        PrevTarget();
                                else
                                        NextTarget();
                                state = false;
												break;

                        case 49:	FocusSection( 1 );	state = false;  break;  // 1 Key
                        case 50:	FocusSection( 2 );	state = false;  break;  // 2 Key
                        case 51:	FocusSection( 3 );	state = false;  break;  // 3 Key
                        case 52:	FocusSection( 4 );	state = false;  break;  // 4 Key
                        case 53:	FocusSection( 5 );	state = false;  break;  // 5 Key
                        case 54:	FocusTarget( 0 );		state = false;  break;  // 6 Key
                        case 55: 	FocusSection( 7 );	state = false;  break;  // 7 Key
                        case 56:	FocusSection( 8 );	state = false;  break;  // 8 Key
                        case 57:	FocusSection( 9 );	state = false;  break;  // 9 Key
                        case 48:	FocusSection( 10 );	state = false;  break;  // 0 Key
                        //default:
                        //        if( code != 0 ) alert( "keycode = " + code);    // lets see what it was for debug reasons
                        //break;


                }
        }

        return state;
}


function getTable( element )            // return table or parent table containing the object
{
        var pa = element.parentNode;
        while (pa.tagName.toLowerCase() != 'table')
                pa = pa.parentNode;
        return( pa );
}


function sendToClipboard(s)
{
        if( window.clipboardData && clipboardData.setData )
        {
                clipboardData.setData("Text", s);
        }
        else
        {
                        alert("Browser does not support Clipboard operations");
        }
}


document.onkeyup= ProcessKeystroke;

function ScrollToTop()
{
        window.scrollTo( 0, 0 );
}

function ClearFocus()
{
        if( lastTarget  != null )
                HideTableTarget ( lastTarget ) 

        lastTarget = null;
}