// Characters.jsl
// Roger Garrett
// 3/21/2010

function Characters()
{
}

// NOTE that this assumes that we have the following at the start of the body of the HTML document:
//
//	<div id="CharacterNub" style="visibility:hidden ; width:7px ; height:7px ; position:absolute; left:0px; top:0px"></div>
//
//	This defines a <DIV> named CharacterNub
//		visibility:hidden		So that the contents of it is never visible to the user.
//		width:7px ; height:7px  It needs a minimum hieght and width. This effectively gets modified automatically when
//								we insert HTML into the DIV, via its innerHTML. We then access the height and width.
//								If we had tried tomake it "too small" some browsers would complain.
//								via the offsetWidtha d offsetHeight properties of this DIV
//		position:absolute;		So that it effectively "overlays" the existing data on the page, although, since the visibility
//								is "hidden" it doesn't actually appear.
//		left:0px; top:0px		So it is positioned within the page. If we had tried to put it off-page some browsers will complain.

// Each entry in this font array corresponds to an individual font.
// The index (key) into the array is the name of the font.
// Each entry in this font array is itself an array, that array
// being indexed (keyed) by pointSize.
Characters.font = new Array();

function Characters.getSize(fontName, pointSize, character)
{
	// returns the height and width of the specified character within
	// the specified fontName at the specified pointSize.
	
	//report("IN Characters.getSize("+fontName+", "+pointSize+", "+character+")\n");
	//reportTabIn();
	
	if (Characters.font[fontName] == null)
	{
		// We do not yet have information for this font.
		// Create an entry for the specified font, that entry
		// itself being an array.
		//report("Creating array for font: "+fontName+"\n");
		Characters.font[fontName] = new Array();
	}
	
	theFontEntry = Characters.font[fontName];
	
	if (theFontEntry[pointSize] == null)
	{
		// We do not yet have information for the font at the
		// specified pointSize.
		// Create an entry for the specified pointSize.
		//report("Creating array for pointSize "+pointSize+"\n");
		theFontEntry[pointSize] = new Array();
	}
	
	var theFontAtThePointSize = theFontEntry[pointSize];
	
	if (theFontAtThePointSize[character] == null)
	{
		// We do not yet have the information for the font at the
		// specified point size for the specified character.
		// Create an entry for the character.
		//report("Creating info for character "+character+"\n");
		theFontAtThePointSize[character] = {width:0,height:0};
		
		html = "<div id='charNub' style='font-family:"+fontName+" ; font-size:"+pointSize+" ; visibility:visible'>";
		html += character;
		html += "</div>";
		
		//report("html = "+html+"\n");
		
		var theCharacterNub = document.getElementById("CharacterNub");
		theCharacterNub.innerHTML = html;
		
		var theNub = document.getElementById("charNub");
		
		theFontAtThePointSize[character].width = theCharacterNub.clientWidth;
		theFontAtThePointSize[character].height = theCharacterNub.clientHeight;
	}

	//reportTabOut();	
	return theFontAtThePointSize[character];
}

function Characters.loadCharacterSizes(fontName, pointSize, characters)
{
	// For the given font at the given pointSize this loads in the sizes for all
	// the characters that are specified in the characters array.
	//
	//	Paremeters:
	//
	//		fontName
	//		pointSize	The point size for which character sizes are to be loaded.
	//		characters	An array of characters whose individual character sizes are to be loaded.
	//
	//	returns true if successful, false otherwise.
	
	report("IN Characters.loadCharacterSizes(fontName, pointSize, characters)\n");
	
	if (fontName == null)
	{
		reportNullObject("Characters.loadCharacterSizes(fontName, pointSize, characters)","fontName");
		return false;
	}
	
	if (pointSize == null)
	{
		reportNullObject("Characters.loadCharacterSizes(fontName, pointSize, characters)","pointSize");
		return false;
	}
	
	if ((characters == null) || !(characters instanceof Array))
	{
		reportNullObject("Characters.loadCharacterSizes(fontName, pointSize, characters)","characters");
		return false;
	}
	
	for (var index = 0 ; index < characters.length ; ++index)
	{
		var thisCharacter = characters[index];
		Characters.getSize(fontName, pointSize, thisCharacter);
	}
}

Characters.standardCharacters = new Array("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z",
		"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z",
		".",",",";",":","<",">","[","]","{","}","(",")","/","?",
		"-","+","=",
		"!","@","#","$","%","^","&","*","~",
		"0","1","2","3","4","5","6","7","8","9");

function Characters.loadStandardCharacters(fontName, pointSize)
{
	report("IN Characters.loadStandardCharacters\n");
	if (fontName == null)
	{
		reportNullObject("Characters.loadStandardCharacters(fontName, pointSize, characters)","fontName");
		return false;
	}
	
	if (pointSize == null)
	{
		reportNullObject("Characters.loadStandardCharacters(fontName, pointSize, characters)","pointSize");
		return false;
	}
	
	return Characters.loadCharacterSizes(fontName, pointSize, Characters.standardCharacters);	
	
}