Textarea Plus

Have a better textarea! A userscript which can improve plain textarea for code editing.

Dovrai installare un'estensione come Tampermonkey, Greasemonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Userscripts per installare questo script.

Dovrai installare un'estensione come ad esempio Tampermonkey per installare questo script.

Dovrai installare un gestore di script utente per installare questo script.

(Ho già un gestore di script utente, lasciamelo installare!)

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

(Ho già un gestore di stile utente, lasciamelo installare!)

// ==UserScript==
// @name Textarea Plus
// @version 3.0.0
// @description Have a better textarea! A userscript which can improve plain textarea for code editing.
// @homepageURL https://github.com/eight04/textarea-plus
// @supportURL https://github.com/eight04/textarea-plus/issues
// @license MIT
// @author eight04 <[email protected]>
// @namespace eight04.blogspot.com
// @include *
// @grant GM_getValue
// @grant GM_setValue
// @grant GM_registerMenuCommand
// @grant GM_addStyle
// @compatible firefox Tampermonkey latest
// @compatible chrome Tampermonkey latest
// @require https://greasyfork.org/scripts/7212-gm-config-eight-s-version/code/GM_config%20(eight's%20version).js?version=156587
// ==/UserScript==

function isSameLine(editor) {
  return !editor.getSelection().includes("\n");
}

function getIndentInfo(text, {indentSize}) {
  var i, count = 0;
  for (i = 0; i < text.length; i++) {
    var c = text[i];
    if (c == " ") {
      count++;
    } else if (c == "\t") {
      count += indentSize;
    } else {
      break;
    }
  }
  return {
    count: Math.floor(count / indentSize),
    extraSpaces: count % indentSize,
    length: i
  };
}

function getIndentChar({indentStyle, indentSize}) {
  if (indentStyle === "TAB") {
    return "\t";
  }
  return " ".repeat(indentSize);
}

function runIndent({editor, options}) {
  if (!isSameLine(editor)) {
    runMultiIndent(editor, options);
    return;
  }
  var range = editor.getSelectionLineRange(),
    line = editor.getSelectionLine(),
    indent = getIndentInfo(line, options),
    pos = editor.getSelectionRange().start;
  if (pos > range.start + indent.length) {
    editor.setRangeText(
      getIndentChar(options),
      pos,
      pos,
      "end"
    );
  } else {
    editor.setRangeText(
      getIndentChar(options).repeat(indent.count + 1),
      range.start,
      range.start + indent.length,
      "end"
    );
  }
}

function runUnindent({editor, options}) {
  if (!isSameLine(editor)) {
    runMultiIndent(editor, options, -1);
    return;
  }
  var range = editor.getSelectionLineRange(),
    line = editor.getSelectionLine(),
    indent = getIndentInfo(line, options),
    pos = editor.getCaretPos(true),
    indentChar = getIndentChar(options);
    
  const indentCount = indent.count + (indent.extraSpaces ? 1 : 0);
  if (pos <= range.start + indent.length && indentCount) {
    editor.setRangeText(
      indentChar.repeat(indentCount - 1),
      range.start,
      range.start + indent.length,
      "end"
    );
  } else if (line.slice(0, pos - range.start).endsWith(indentChar)) {
    editor.setRangeText(
      "", pos - indentChar.length, pos, "end"
    );
  }
}

function runMultiIndent(editor, options, diff = 1) {
  var range = editor.getSelectionRange(),
    lines = editor.getSelectionLine(),
    lineRange = editor.getSelectionLineRange();
  if (lines[range.end - lineRange.start - 1] == "\n") {
    lineRange.end = range.end - 1;
    lines = lines.slice(0, range.end - lineRange.start - 1);
  }
  lines = lines.split("\n").map(line => {
    if (!line) return line;
    var indent = getIndentInfo(line, options),
      count = indent.count + diff;
    if (count < 0) {
      count = 0;
      // remove extra space when there is no indent
      indent.extraSpaces = 0;
    }
    return getIndentChar(options).repeat(count) +
      " ".repeat(indent.extraSpaces) +
      line.slice(indent.length);
  }).join("\n");
  editor.setRangeText(lines, lineRange.start, lineRange.end);
  editor.setSelectionRange(lineRange.start, lineRange.start + lines.length + 1);
}

function runSmartHome({editor, options, event}) {
  const collapse = !event.shiftKey;
  var line = editor.getCurrentLine(),
    range = editor.getCurrentLineRange(),
    pos = editor.getCaretPos(collapse) - range.start,
    indent = getIndentInfo(line, options);
  if (pos == indent.length) {
    editor.setCaretPos(range.start, collapse);
  } else {
    editor.setCaretPos(range.start + indent.length, collapse);
  }
}

const BRACES = {
  __proto__: null,
  "[": "]",
  "{": "}",
  "(": ")",
};

function runNewLine({editor, options}) {
  var content = editor.getContent(),
    range = editor.getSelectionRange(),
    line = editor.getSelectionLine(),
    lineRange = editor.getLineRange(range.start, range.start),
    indent = getIndentInfo(line, options),
    out = "\n", pos,
    left = content[range.start - 1],
    right = content[range.end];

  if (/[[{(]/.test(left)) {
    out += getIndentChar(options).repeat(indent.count + 1);
  } else {
    out += line.slice(0, Math.min(indent.length, range.start - lineRange.start));
  }
  pos = range.start + out.length;
  if (BRACES[left] && right == BRACES[left]) {
    out += "\n" + line.slice(0, indent.length);
  }
  editor.setRangeText(out);
  editor.setSelectionRange(pos, pos);
}

function runCompleteBraces({editor, options, event}) {
  const left = event.key;
  const right = options.completeBraces[left];
  var text = editor.getSelection(),
    range = editor.getSelectionRange();
  editor.setRangeText(left + text + right, range.start, range.end);
  editor.setSelectionRange(range.start + 1, range.start + 1 + text.length);
}

const COMMANDS = [
  {
    // indent
    test: e => e.key === "Tab" && !e.shiftKey,
    run: runIndent
  },
  {
    // unindent
    test: e => e.key === "Tab" && e.shiftKey,
    run: runUnindent
  },
  {
    // smart home
    test: e => e.key === "Home",
    run: runSmartHome
  },
  {
    // new line
    test: e => e.key === "Enter",
    run: runNewLine
  },
  {
    // complete braces
    test: (e, {completeBraces}) => completeBraces[e.key],
    run: runCompleteBraces
  }
];

const DEFAULT_OPTIONS = {
  indentSize: 4,
  indentStyle: "TAB",
  completeBraces: {
    __proto__: null,
    "[": "]",
    "{": "}",
    "(": ")",
    "\"": "\"",
    "'": "'"
  }
};

function createCommandExecutor(options = {}) {
  options = Object.assign({}, DEFAULT_OPTIONS, options);
  
  function run(event, editorFactory) {
    for (const command of COMMANDS) {
      if (command.test(event, options)) {
        event.preventDefault();
        command.run({editor: editorFactory(), options, event});
        break;
      }
    }
  }

	return {run};
}

/* eslint-env browser, greasemonkey */

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;
		j = content.indexOf("\n", end);
		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 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;
}

let commandExcutor, styleEl;

GM_config.setup({
  indentSize: {
    label: "Indent size",
    type: "number",
    default: 4
  },
  indentStyle: {
    label: "Indent style",
    type: "radio",
    default: "TAB",
    options: {
      TAB: "Tab",
      SPACE: "Space"
    }
  },
  completeBraces: {
    label: "Complete braces. One pair per line",
    type: "textarea",
    default: "[]\n{}\n()"
  }
}, () => {
  const options = GM_config.get();
  options.completeBraces = createMap(options.completeBraces);
  commandExcutor = createCommandExecutor(options);
  if (styleEl) styleEl.remove();
  styleEl = GM_addStyle(`
    textarea {
      tab-size: ${options.indentSize};
      -moz-tab-size: ${options.indentSize};
      -o-tab-size: ${options.indentSize};
    }`
  );
  
  function createMap(text) {
    const map = {__proto__: null};
    for (const pair of text.split(/\s+/g)) {
      if (pair.length == 2) {
        map[pair[0]] = pair[1];
      } else if (pair.length != 0) {
        alert(`Invalid pair: ${pair}`);
      }
    }
    return map;
  }
});

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

  commandExcutor.run(e, () => new Editor(e.target));
});