// JavaScript Document
/* 
REQUISITI: ajax_request.js
*/
	function initOverlayImage(){
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		objOverlay.style.display = 'none';
		//objOverlay.onclick = function() { alert('clicked overlay'); }	
		var objBody = document.getElementsByTagName("body").item(0);
		objBody.appendChild(objOverlay);
	}
	
	function showOverlayImage(){
		var overlay_width=500;
		var overlay_height=500;
		var vPageSize=getPageSize();
		var vPageScroll=getPageScroll();
		var objOverlay = document.getElementById("overlay");
		
		//objOverlay.style.width=overlay_width+'px';
		//objOverlay.style.height=overlay_height+'px';
		//objOverlay.className = 'div_overlay';
		
		objOverlay.style.top =vPageScroll[1]+(vPageSize[3]/2-(overlay_height/2))+'px';
		objOverlay.style.left = (((vPageSize[0]/2)-(overlay_width/2))/2)*2+'px';
		
//		FadeIn('overlayshadow',300);
//		objOverlay.style.top = '100px';
//		objOverlay.style.height=overlay_height+'px';
	}
	
	
	function initOverlayShadowImage(){
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlayshadow');
		objOverlay.style.display = 'none';
		objOverlay.onclick = function() { hideOverPage(); }	
		var objBody = document.getElementsByTagName("body").item(0);
		objBody.appendChild(objOverlay);
		
	}
	
	function showOverlayShadowImage(){
		var vPageSize=getPageSize();
		var objOverlay = document.getElementById("overlayshadow");
		objOverlay.style.display = '';
		objOverlay.className = 'div_ombra';
		objOverlay.style.left = '0';
		objOverlay.style.top = '0';
		objOverlay.style.width=vPageSize[0]+'px';
		objOverlay.style.height=vPageSize[1]+'px';

	}
	
	
	// mostra la pagina in popup
	function showOverPageImage(){
		try{hideOverPage()}catch(e){}
		initOverlayShadowImage();
		showOverlayShadowImage();
		initOverlayImage();
		showOverlayImage();
	}
	

	// nasconde la pagine in popup	
	function hideOverPageImage(){
		var objBody = document.getElementsByTagName("body").item(0);
		objBody.removeChild(document.getElementById('overlayshadow'));
		objBody.removeChild(document.getElementById('overlay'));		
		last_id_clicked='';
	}
		
		
	function resizeOverlayImage(){
		var vPageSize=getPageSize();	
		var objOverlay = document.getElementById("overlayshadow");
		objOverlay.style.width=vPageSize[0];
		objOverlay.style.height=vPageSize[1];		
	}
	
	function centerOverlayImage(){
	
		var vPageSize=getPageSize();
		var vPageScroll=getPageScroll();
		var objOverlay = document.getElementById("overlay");

		var overlay_width=objOverlay.offsetWidth;
		var overlay_height=objOverlay.offsetHeight;
		
		//objOverlay.style.display = '';
		//objOverlay.className = 'div_overlay';
		objOverlay.style.left = (((vPageSize[0]/2)-(overlay_width/2))/2)*2+'px';


		objOverlay.style.top =vPageScroll[1]+(vPageSize[3]/2-(overlay_height/2));
		//objOverlay.style.top = (((vPageScroll[1]/2)-(overlay_height/2))/2)*2+'px';
		
		//objOverlay.style.top=vPageScroll[1]+20+'px';
		//objOverlay.style.width=overlay_width+'px';

	}

function ZoomImage(image, description){
		id_image=image;
		img_description=description;
		showOverPageImage();
		centerOverlayImage();
		document.getElementById('overlay').innerHTML='<div style="position:absolute; right:50%; top:50%; margin:-100px 0 0 -100px;"><img src="img/loading.gif" align="absmiddle" /></div>';
		document.getElementById('overlay').style.display='';
		AyaxRequest('ajax_request.php', 'POST', 'filetocall=zoomimage&image='+image+'&id_image='+id_image, ZoomImageHTML);		
}

function ZoomImageHTML(){
	//creo il contenitore
	var objContainer = document.createElement("div");
	objContainer.setAttribute('id','imgContainer');
	var objBody = document.getElementsByTagName("body").item(0);
	objBody.appendChild(objContainer);
	document.getElementById('imgContainer').style.left='0px';
	document.getElementById('imgContainer').style.top='0px';	
	document.getElementById('imgContainer').style.width='0px';	
	document.getElementById('imgContainer').style.height='0px';	
	objContainer.className = 'div_basic';
	//objContainer.style.display='none';
	// assegno al contenitore il codice html proveniente dal server
	document.getElementById('imgContainer').innerHTML=this.req.responseText;
	
	// assegno all envento onLoad dell' immagine la relativa funzione
		document.getElementById(id_image).onload = function() { imageOnLoad(); }	
}

function imageOnMouseOver(){
	try{
		if (img_description){
			setAltDiv();
			changeOpac(0, 'altContainer');
			opacity('altContainer', 0, 100, 100);
			id2follow='altContainer';
			document.onmousemove=followmouse;
		}
	}catch(e){alert(e)}
}


function imageOnLoad(){
	opacity(id_image, 100, 0, 100);
	window.setTimeout('setOverlay()',100);
}

function imageOnClick(){
	imageOnMouseOut();	
	hideOverPage();
}


function imageOnMouseOut(){
	try{
		var objBody = document.getElementsByTagName("body").item(0);
		objBody.removeChild(document.getElementById('altContainer'));
		document.onmousemove='';
	}catch(e){	}
}

function setAltDiv(){
	
	// creo il contenitore per l'alt div
	var objContainer = document.createElement("div");
	objContainer.setAttribute('id','altContainer');
	var objBody = document.getElementsByTagName("body").item(0);
	objBody.appendChild(objContainer);
	
	var immagine=document.getElementById(id_image);

	document.getElementById('altContainer').style.left=mouseX + 'px';
	document.getElementById('altContainer').style.top=mouseY + 'px';
	document.getElementById('altContainer').className = 'div_alt';
	document.getElementById('altContainer').innerHTML=img_description;

}



function setOverlay(){
	var vPageSize=getPageSize();
	var vPageScroll=getPageScroll();
	
	// nascondo l' overlay
	changeOpac(0, id_image);

	// dimensiono l' overlay
	document.getElementById('overlay').style.width=(document.getElementById(id_image).width+6)+'px';
	document.getElementById('overlay').style.height=(document.getElementById(id_image).height+20)+'px';
	document.getElementById('overlay').innerHTML=document.getElementById('imgContainer').innerHTML;
	//centerOverlayImage();
	document.getElementById('overlay').style.display='';
	document.getElementById('overlay').className='div_overlay';

	var overlay_width=(document.getElementById(id_image).width+20);
	var overlay_height=(document.getElementById(id_image).height+20);
	
	document.getElementById('overlay').style.left = (((vPageSize[0]/2)-(overlay_width/2))/2)*2+'px';
	document.getElementById('overlay').style.top =vPageScroll[1]+(vPageSize[3]/2-(overlay_height/2));

// fade in
	opacity(id_image, 0, 100, 300);
	
	// eventi per l'immagine
	document.getElementById(id_image).onclick = function() { imageOnClick(); }	
	//document.getElementById(id_image).onmouseover = function() { imageOnMouseOver(); }	
	//document.getElementById(id_image).onmouseout = function() { imageOnMouseOut(); }	
	

	// distruggo il contenitore dell' immagine
	var objBody = document.getElementsByTagName("body").item(0);
	objBody.removeChild(document.getElementById('imgContainer'));

}