Loot-Quest

Console.js (6547B)

---

 /*
 A DOS-like output console for JavaScript.
 http://www.codeproject.com/script/Articles/MemberArticles.aspx?amid=3290305
 
 Example usage:
 var console = new Console('myConsoleDivId', 20, 40);
 console.println('A console window with 20 rows and 40 characters.');
 console.setCursorPosition(6,6);
 console.print('Printing in row 6, column 6');
 
 To get user-input, include the URL of PromptWindow.htm in the constructor:
 var console = new Console('myConsoleDivId', 20, 40);
 var yourName = console.input('What is your name? ');
 console.println('Hello, ' + yourName);
 
 */
 
 
 
 function Console(elementId, rows, columns, promptWindowUrl) {
 	/// <summary>Creates a new Console in the HTML element with given ID, with the specified rows and columns, and optionally the URL to the PromptWindow if the input() function is used.</summary>
 
 	// Get a reference to the HTML element which will hold the console.
 	this.element = document.getElementById(elementId);
 	if (!this.element) {
 		alert('No element with the ID ' + elementId + ' was found.');
 		return;
 	}
 	// remove any child nodes of the element
 	while (this.element.hasChildNodes()) {
 		this.element.removeChild(this.element.childNodes[0]);
 	}
 	// make sure it acts like a 'pre'
 	this.element.style.whiteSpace = 'pre';
 
 	this.rows = Math.floor(rows);
 	this.columns = Math.floor(columns);
 	this.cursorPosition = {
 		row: 0,
 		column: 0
 	};
 	this.charGrid = new Array(this.rows);
 	this.promptWindowUrl = promptWindowUrl;
 
 
 	// add the TextNode objects
 	for (var i = 0; i < rows; i++) {
 		var textNode = document.createTextNode('');
 		this.charGrid[i] = textNode;
 		this.element.appendChild(textNode);
 		if (i < rows - 1) {
 			// add a line break between each TextNode
 			this.element.appendChild(document.createElement('br'));
 		}
 	}
 
 	// clear the console screen
 	this.cls();
 
 }
 
 Console.prototype.cls = function () {
 	/// <summary>Clears all the characters from the console and sets the cursor to 0,0.</summary>
 
 	// go through each row
 	for (var row = 0; row < this.rows; row++) {
 
 		// get the text node, make a string with 'col' spaces, and set this row as the string
 		var textNode = this.charGrid[row];
 		var s = '';
 		for (var col = 0; col < this.columns; col++) {
 			s += ' ';
 		}
 		textNode.data = s;
 	}
 	// move cursor to 0,0
 	this.setCursorPos(0, 0);
 };
 
 Console.prototype.printAt = function (row, column, str, cycle) {
 	/// <summary>Private function - not intended to be used by outside programs. Prints a string at the given row and column, and optionally wraps the text if needed.</summary>
 	if (row >= this.rows || row < 0 || column < 0 || !str) {
 		// nothing to print
 		return;
 	}
 
 	// get the text in the target row
 	var oldRow = this.charGrid[row].data;
 
 	// tentatively put the new text for the row in newRow. This is probably too long or too short
 	var newRow = oldRow.substring(0, column) + str;
 
 	if (newRow.length < this.columns) {
 		// the text was too short, so get the remaining characters from the old string.
 		// E.g.: oldRow = "0123456789", printing "hi" over '4' so newRow = "0123hi", then appending "6789" to get "0123hi6789"
 		newRow += oldRow.substring(column + str.length);
 		// move the cursor to the character after the new string, e.g. just after "hi".
 		this.setCursorPos(row, column + str.length);
 	} else {
 		// need to wrap to the next row.
 		this.setCursorPos(row + 1, 0);
 		if (cycle && this.cursorPosition.row >= this.rows) {
 			// moved passed the bottom of the console.  Need to delete the first line, and move each line up by one.
 			for (var rowIndex = 0; rowIndex < this.rows - 1; rowIndex++) {
 				this.charGrid[rowIndex].data = this.charGrid[rowIndex + 1].data;
 			}
 			// After moving up, there needs to be a new row at the bottom. Set to empty string.
 			var emptyRow = '';
 			for (var col = 0; col < this.columns; col++) {
 				emptyRow += ' ';
 			}
 			this.charGrid[this.rows - 1].data = emptyRow;
 			// Cycled the lines up, so the current row should cycle by one as well
 			this.cursorPosition.row--;
 			row--;
 		}
 	}
 
 	// truncate the text if it is too long
 	if (newRow.length > this.columns) {
 		newRow = newRow.substring(0, this.columns);
 	}
 	// set the text to the current row.
 	this.charGrid[row].data = newRow;
 };
 
 Console.prototype.print = function (str) {
 	/// <summary>Prints the given string at the current cursor position, wrapping text where necessary.</summary>
 
 	// get new location of cursor after text added
 	var newColumnPos = this.cursorPosition.column + str.length;
 
 	if (newColumnPos > this.columns) {
 		// text is too long to fit on one line.  Add as much as possible, then recursively call print with the remainder of the string
 
 		var charsLeftOnCurLine = this.columns - this.cursorPosition.column;
 		var s = str.substring(0, charsLeftOnCurLine);
 
 		// print the first part
 		this.print(s);
 
 		// print rest of string
 		this.print(str.substring(charsLeftOnCurLine));
 
 	} else {
 		// print the string at the current cursor position
 		this.printAt(this.cursorPosition.row, this.cursorPosition.column, str, true);
 	}
 
 };
 
 Console.prototype.println = function (str) {
 	/// <summary>Prints the given string at the current cursor position, wrapping text where necessary, and appends a line break.</summary>
 	if (!str) {
 		str = '';
 	}
 
 	// Actually, we don't add line-breaks. We simply pad out the line with spaces to that the cursor will be forced to the next line.
 	var extraSpaces = this.columns - ((this.cursorPosition.column + str.length) % this.columns);
 	var s2 = str;
 	for (var i = 0; i < extraSpaces; i++) {
 		s2 += ' ';
 	}
 	this.print(s2);
 };
 
 Console.prototype.setCursorPos = function (row, column) {
 	/// <summary>Sets the cursor position to the given row and column.</summary>
 	this.cursorPosition.row = row;
 	this.cursorPosition.column = column;
 };
 
 Console.prototype.input = function (message) {
 	/// <summary>Gets textual input from the user, and prints the message and the user's input to the screen.</summary>
 	if (message) {
 		this.print(message);
 	}
 
 	var result;
 	if (window.showModalDialog) {
 		// IE7 blocks calls to window.prompt (insanity!), so we need to use their showModalDialog
 		if (!this.promptWindowUrl) {
 			alert('JS Console Error\nConsole.promptWindowUrl not set. Set this to the URL of PromptWindow.htm\nPrompts disabled in Internet Explorer.');
 			return '';
 		}
 		result = window.showModalDialog(this.promptWindowUrl, message, "dialogWidth:300px;dialogHeight:200px");
 	} else {
 		result = prompt(message);
 	}
 
 	if (result) {
 		this.println(result);
 		return result;
 	} else {
 		return '';
 	}
 };