function OnInit(initData)
{
	initData.name = "SHA-256 and SHA-512";
	initData.version = "2.1";
	initData.copyright = "(c) 2019-2021 Leo Davidson";
	initData.url = "https://resource.dopus.com/t/column-sha-256/33525/1";
	initData.desc = "SHA-256 and SHA-512 hash columns";
	initData.default_enable = true;
	initData.min_version = "12.23";
}

function OnAddColumns(addColData)
{
	AddColumn(addColData, "SHA256", "SHA256", "sha256");
	AddColumn(addColData, "SHA512", "SHA512", "sha512");
}

function AddColumn(addColData, colName, colLabel, hashName)
{
	var col = addColData.AddColumn();

	col.name = colName;
	col.label = colLabel;

	col.method = "OnColumns";
	col.multicol = true;

	col.justify = "left";
	col.autogroup = true;
	col.autorefresh = true;

	// Setting the timeout to zero tells Opus to Wait for us forever without giving up.
	// Hashing large files can take a long time.
	col.timeout = 0;
	
	col.userdata = hashName;
}

// Implement the columns
function OnColumns(scriptColData)
{
	try
	{
		var item = scriptColData.item;
		if (item.is_dir) return;

		// Work out which hashes to calculate.
		// Opus can calculate more than one at once, to avoid reading the file multiple times if multiple hash columns are displayed.

		var algorithms = "";
		var multiple = false;

		for (var e = new Enumerator(scriptColData.columns); !e.atEnd(); e.moveNext())
		{
			var colName = e.item();
			var colData = scriptColData.columns(colName);
			if (algorithms != "")
			{
				algorithms += ",";
				multiple = true;
			}
			algorithms += colData.userdata;
		}

		if (algorithms == "") return;

		// If we request one hash, hashes will be set to the string result.
		// If we request more than one, hashes will be set to a vector of strings.
		
		var hashes = DOpus.FSUtil().Hash(scriptColData.item.realpath, algorithms);

		var idx = 0;		

		for (var e = new Enumerator(scriptColData.columns); !e.atEnd(); e.moveNext())
		{
			var colName = e.item();
			var colData = scriptColData.columns(colName);
			if (multiple)
			{
				colData.value = hashes(idx++);
			}
			else
			{
				colData.value = hashes;
			}
		}
	}
	catch(e)
	{
		for (var e = new Enumerator(scriptColData.columns); !e.atEnd(); e.moveNext())
		{
			var colName = e.item();
			var colData = scriptColData.columns(colName);
			colData.value = "";
		}
	}
}