Textarea Plus

An userscript to improve plain textarea for code editing.

Versión del día 28/1/2017. Echa un vistazo a la versión más reciente.

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

You will need to install an extension such as Tampermonkey to install this script.

Tendrás que instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Tendrás que instalar una extensión como Tampermonkey antes de poder instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

// ==UserScript==
// @name        Textarea Plus
// @description	An userscript to improve plain textarea for code editing.
// @namespace   eight04.blogspot.com
// @include     *
// @version     2.0.0
// @grant       GM_addStyle
// ==/UserScript==

class Editor {
	constructor(textarea) {
		this.el = textarea;
	}

	getSelectionRange() {
		return {
			start: this.el.selectionStart,
			end: this.el.selectionEnd
		};
	}

	setSelectionRange(start, end) {
		this.el.setSelectionRange(start, end);
	}

	getCaretPos(collapse = false) {
		if (this.el.selectionDirection == "backward" || collapse) {
			return this.el.selectionStart;
		}
		return this.el.selectionEnd;
	}
	
	setCaretPos(pos, collapse = false) {
		if (collapse) {
			this.setSelectionRange(pos, pos);
		} else {
			var start = this.el.selectionStart,
				end = this.el.selectionEnd,
				dir = this.el.selectionDirection;
				
			if (dir == "backward") {
				[start, end] = [end, start];
				dir = "forward";
			}
			end = pos;
			if (end < start) {
				[start, end] = [end, start];
				dir = "backward";
			}
			this.el.selectionEnd = end;
			this.el.selectionStart = start;
			this.el.selectionDirection = dir;
		}
	}

	getLineRange(start, end) {
		var content = this.getContent(),
			i, j;
		i = content.lastIndexOf("\n", start - 1) + 1;
		if (content[end - 1] == "\n") {
			j = end;
		} else {
			j = content.indexOf("\n", end) + 1;
			if (j == 0) {
				j = content.length;
			}
		}
		return {
			start: i,
			end: j
		};
	}

	getSelectionLineRange() {
		var range = this.getSelectionRange();
		return this.getLineRange(range.start, range.end);
	}

	getSelectionLine() {
		var content = this.getContent(),
			range = this.getSelectionLineRange();
		return content.slice(range.start, range.end);
	}

	getCurrentLineRange() {
		var pos = this.getCaretPos();
		return this.getLineRange(pos, pos);
	}

	getCurrentLine() {
		var range = this.getCurrentLineRange(),
			content = this.getContent();
		return content.slice(range.start, range.end);
	}

	getContent() {
		return this.el.value;
	}

	getSelection() {
		var content = this.getContent(),
			range = this.getSelectionRange();
		return content.slice(range.start, range.end);
	}

	setRangeText(...args) {
		this.el.setRangeText(...args);
	}
}

var braceMatch = {
	"[": "]",
	"{": "}",
	"(": ")"
};

class Commands {
	constructor(editor) {
		this.editor = editor;
		this.indentSize = 4;
		this.indentChar = "\t";
	}
	sameLine() {
		return !this.editor.getSelection().includes("\n");
	}
	betweenText() {
		var line = this.editor.getSelectionLine(),
			pos = this.editor.getCaretPos(),
			lineRange = this.editor.getSelectionLineRange(),
			match = line.match(/\S/);
		if (!match) {
			return false;
		}
		return pos >= lineRange.start + match.index;
	}
	getIndentInfo(text) {
		var i, count = 0;
		for (i = 0; i < text.length; i++) {
			var c = text[i];
			if (c == " ") {
				count++;
			} else if (c == "\t") {
				count += 4;
			} else {
				break;
			}
		}
		return {
			count: Math.floor(count / this.indentSize),
			length: i
		};
	}
	indent() {
		if (this.sameLine()) {
			var range = this.editor.getSelectionLineRange(),
				line = this.editor.getSelectionLine(),
				indent = this.getIndentInfo(line),
				pos = this.editor.getSelectionRange().start;
			if (pos >= range.start + indent.length) {
				this.editor.setRangeText(
					this.indentChar,
					pos,
					pos,
					"end"
				);
			} else {
				this.editor.setRangeText(
					this.indentChar.repeat(indent.count + 1),
					range.start,
					range.start + indent.length,
					"end"
				);
			}
		} else {
			this.multiIndent();
		}
		return true;
	}
	multiIndent(diff = 1) {
		var lines = this.editor.getSelectionLine().split("\n"),
			range = this.editor.getSelectionLineRange();
		lines = lines.map(line => {
			if (!line) return line;
			var indent = this.getIndentInfo(line),
				count = indent.count + diff;
			if (count < 0) count = 0;
			return this.indentChar.repeat(count) + line.slice(indent.length);
		}).join("\n");
		this.editor.setRangeText(lines, range.start, range.end, "select");
	}
	unindent() {
		if (this.sameLine()) {
			var range = this.editor.getSelectionLineRange(),
				line = this.editor.getSelectionLine(),
				indent = this.getIndentInfo(line),
				pos = this.editor.getCaretPos(true);
			if (pos <= range.start + indent.length && indent.count) {
				this.editor.setRangeText(
					this.indentChar.repeat(indent.count - 1),
					range.start,
					range.start + indent.length,
					"end"
				);
			} else if (line.slice(0, pos - range.start).endsWith(this.indentChar)) {
				this.editor.setRangeText(
					"", pos - this.indentChar.length, pos, "end"
				);
			}
		} else {
			this.multiIndent(-1);
		}
		return true;
	}
	smartHome(collapse = false) {
		var line = this.editor.getCurrentLine(),
			range = this.editor.getCurrentLineRange(),
			pos = this.editor.getCaretPos(collapse) - range.start,
			indent = this.getIndentInfo(line);
		if (pos == indent.length) {
			this.editor.setCaretPos(range.start, collapse);
		} else {
			this.editor.setCaretPos(range.start + indent.length, collapse);
		}
		return true;
	}
	newLineIndent() {
		var content = this.editor.getContent(),
			range = this.editor.getSelectionRange(),
			line = this.editor.getSelectionLine(),
			indent = this.getIndentInfo(line),
			out = "\n", pos,
			left = content[range.start - 1],
			right = content[range.end];

		if (/[\[{(]/.test(left)) {
			out += this.indentChar.repeat(indent.count + 1);
		} else {
			out += line.slice(0, indent.length);
		}
		pos = range.start + out.length;
		if (right == braceMatch[left]) {
			out += "\n" + line.slice(0, indent.length);
		}
		this.editor.setRangeText(out);
		this.editor.setSelectionRange(pos, pos);
		return true;
	}
	completeBraces(left) {
		var right = braceMatch[left];
		if (!right) return false;
		var text = this.editor.getSelection(),
			range = this.editor.getSelectionRange();
		this.editor.setRangeText(left + text + right, range.start, range.end);
		this.editor.setSelectionRange(range.start + 1, range.start + 1 + text.length);
		return true;
	}
}

var ignoreClassList = ["CodeMirror", "ace_editor"];

function validArea(area) {
	if (area.nodeName != "TEXTAREA") {
		return false;
	}

	if (area.dataset.textareaPlus === "false") {
		return false;
	}

	if (area.dataset.textareaPlus === "true") {
		return true;
	}

	var node = area, i;
	while ((node = node.parentNode) != document.body) {
		for (i = 0; i < ignoreClassList.length; i++) {
			if (node.classList.contains(ignoreClassList[i])) {
				area.dataset.textareaPlus = "false";
				return false;
			}
		}
	}

	area.dataset.textareaPlus = "true";
	return true;
}

window.addEventListener("keydown", function(e){
	if (!validArea(e.target) || e.ctrlKey || e.altKey) {
		return;
	}
	if (e.defaultPrevented) {
		return;
	}

	function commands() {
		return new Commands(new Editor(e.target));
	}

	var result = false;

	if (e.keyCode == 9) {
		// tab
		if (e.shiftKey) {
			result = commands().unindent();
		} else {
			result = commands().indent();
		}
	} else if (e.keyCode == 13) {
		// enter
		result = commands().newLineIndent();
	} else if (e.keyCode == 36) {
		// home
		result = commands().smartHome(!e.shiftKey);
	} else if (braceMatch[e.key]) {
		// braces
		result = commands().completeBraces(e.key);
	}

	if (result) {
		e.preventDefault();
	}
});

GM_addStyle("textarea {tab-size: 4; -moz-tab-size: 4; -o-tab-size: 4;}");