Textarea Plus

An userscript to improve plain textarea for code editing.

Verzia zo dňa 28.01.2017. Pozri najnovšiu verziu.

Na nainštalovanie skriptu si budete musieť nainštalovať rozšírenie, ako napríklad Tampermonkey, Greasemonkey alebo Violentmonkey.

Na inštaláciu tohto skriptu je potrebné nainštalovať rozšírenie, ako napríklad Tampermonkey.

Na nainštalovanie skriptu si budete musieť nainštalovať rozšírenie, ako napríklad Tampermonkey, % alebo Violentmonkey.

Na nainštalovanie skriptu si budete musieť nainštalovať rozšírenie, ako napríklad Tampermonkey alebo Userscripts.

Na inštaláciu tohto skriptu je potrebné nainštalovať rozšírenie, ako napríklad Tampermonkey.

Na inštaláciu tohto skriptu je potrebné nainštalovať rozšírenie správcu používateľských skriptov.

(Už mám správcu používateľských skriptov, nechajte ma ho nainštalovať!)

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie, ako napríklad Stylus.

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie, ako napríklad Stylus.

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie, ako napríklad Stylus.

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie správcu používateľských štýlov.

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie správcu používateľských štýlov.

Na inštaláciu tohto štýlu je potrebné nainštalovať rozšírenie správcu používateľských štýlov.

(Už mám správcu používateľských štýlov, nechajte ma ho nainštalovať!)

// ==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;}");