/*  RENDER -- Show a preview image on the display.
*/
function render(url) 
{
    document.getElementById('resFrame').style.display='none';
    document.getElementById('imgFrame').style.display='block';
    document.getElementById('back').style.display='block';
    document.getElementById('img').src=url;
}

/*  BACK -- Go back to the result table after displaying a preview image.
*/
function back() 
{
    document.getElementById('imgFrame').style.display='none';
    document.getElementById('back').style.display='none';
    document.getElementById('resFrame').style.display='block';
}


function updateOrientation()
{
    if (window.orientation != 0) {
	window.location = "/iportal/orient.html";
    } else {
	history.go(-1);
    }
}


/*  SHOWDIV -- Show the specified <div> element on the display, hiding
**  all other elements.
*/
function showDiv(dval) 
{
  if (dval == 0) {				// Show Coordinates div
     document.getElementById('Coords').style.display = 'block';
     document.getElementById('Image').style.display  = 'none';
     document.getElementById('Status').style.display = 'none';
  } else if (dval == 1) {			// Show Image Display div
     document.getElementById('Coords').style.display = 'none';
     document.getElementById('Image').style.display  = 'block';
     document.getElementById('Status').style.display = 'none';
  } else {					// Show Search Status div
     document.getElementById('Coords').style.display = 'none';
     document.getElementById('Image').style.display  = 'none';
     document.getElementById('Status').style.display = 'block';
  }
} 

function toggleControls() 
{
  if (document.getElementById('controls').style.visibility == 'hidden') {
      document.getElementById('controls').style.visibility = 'visible';
      if (i_scale > 0.03125)
          document.getElementById('zoomIn').style.visibility = 'visible';
      if (i_scale < 8)
          document.getElementById('zoomOut').style.visibility = 'visible';
      document.getElementById('controls').style.display = 'block';
  } else {
      document.getElementById('controls').style.visibility = 'hidden';
      document.getElementById('zoomIn').style.visibility = 'hidden';
      document.getElementById('zoomOut').style.visibility = 'hidden';
      document.getElementById('controls').style.display = 'none';
  }
}

/*  SCALE -- Zoom the display by the specified amount.
*/
function Scale(scale) 
{ 
  var abs_s = Math.abs(scale);

  i_scale = (scale < 0) ?  (i_scale / abs_s) : (i_scale * abs_s);
  field_size = 0.25 * i_scale;


  if (sloan == 1) {				// Doing SDSS image.
     if (i_scale < 0.03125) {  			// Check limits
         i_scale = 0.03125;
         field_size = 0.25 * i_scale;
         document.getElementById('zoomIn').style.visibility = 'hidden';
     } else if (i_scale > 8) {
         i_scale = 8;
         field_size = 0.25 * i_scale;
         document.getElementById('zoomOut').style.visibility = 'hidden';
     } else {
         document.getElementById('zoomIn').style.visibility = 'visible';
         document.getElementById('zoomOut').style.visibility = 'visible';
     }

     field_scale = s_scale * i_scale;
     document.getElementById('Img').src = im_url + 
	"&ra=" + im_ra + "&dec=" + im_dec + "&scale=" + field_scale; 

  } else {
     if (i_scale < 0.03125) {  			// Check limits
         i_scale = 0.03125;
         field_scale = field_size * 60.0;
         document.getElementById('zoomIn').style.visibility = 'hidden';
     } else if (i_scale == 1) {			// restore default zoom
         field_size = 0.25;
         field_scale = 15.0;
         document.getElementById('zoomOut').style.visibility = 'visible';
     } else if (i_scale >= 2) {
         i_scale = 2;
         field_size = 0.333;			// fixed at 20'
         field_scale = 20.0;			// fixed at 20'
         document.getElementById('zoomOut').style.visibility = 'hidden';
     } else {
         field_scale = field_size * 60.0;
         document.getElementById('zoomIn').style.visibility = 'visible';
         document.getElementById('zoomOut').style.visibility = 'visible';
     }

     document.getElementById('Img').src = im_url + 
	"&r=" + im_ra + "&d=" + im_dec + 
	"&h=" + field_scale + "&w=" + field_scale; 
  }

  document.getElementById('slab').innerHTML=field_size+" deg";
}


/*  MOVE --  Move the field of view 33% in the indicated direction.
*/
function Move(dir) 
{ 
  var x = im_ra;
  var y = im_dec;
  var delta = field_size / 3.0;

  if (dir == 1)					// North
     y = y + delta;
  else if (dir == 2)				// South
     y = y - delta;
  else if (dir == 3)				// East
     x = x + delta;
  else if (dir == 4)				// West
     x = x - delta;

  if (sloan == 1) {				// Doing SDSS image.
     field_scale = s_scale * i_scale;
     document.getElementById('Img').src = im_url + 
	"&ra=" + x + "&dec=" + y + "&scale=" + field_scale; 

  } else {
     document.getElementById('Img').src = im_url + 
	"&r=" + x + "&d=" + y + 
	"&h=" + (field_size*60.0) + "&w=" + (field_size*60.0); 
  }

  im_ra = x;
  im_dec = y;
  field_size = 0.25 * i_scale;
}


/*  SHOWSTATUS -- Show the status panel.
*/
function showStatus() 
{
  if (document.getElementById("Status").style.display == "block") {
     document.getElementById("Status").style.display = "none";
     document.getElementById("OptButtons").style.display = "block";
  } else {
     document.getElementById("Status").style.display = "block";
     document.getElementById("OptButtons").style.display = "none";
  }
}