src/SelectionManager.ts

   1 /**
   2  * @license MIT
   3  */
   4
   5 import * as Mouse from './utils/Mouse';
   6 import * as Browser from './utils/Browser';
   7 import { CharMeasure } from './utils/CharMeasure';
   8 import { CircularList } from './utils/CircularList';
   9 import { EventEmitter } from './EventEmitter';
  10 import { ITerminal, ICircularList } from './Interfaces';
  11 import { SelectionModel } from './SelectionModel';
  12 import { translateBufferLineToString } from './utils/BufferLine';
  13
  14 /**
  15  * The number of pixels the mouse needs to be above or below the viewport in
  16  * order to scroll at the maximum speed.
  17  */
  18 const DRAG_SCROLL_MAX_THRESHOLD = 50;
  19
  20 /**
  21  * The maximum scrolling speed
  22  */
  23 const DRAG_SCROLL_MAX_SPEED = 15;
  24
  25 /**
  26  * The number of milliseconds between drag scroll updates.
  27  */
  28 const DRAG_SCROLL_INTERVAL = 50;
  29
  30 /**
  31  * A string containing all characters that are considered word separated by the
  32  * double click to select work logic.
  33  */
  34 const WORD_SEPARATORS = ' ()[]{}\'"';
  35
  36 // TODO: Move these constants elsewhere, they belong in a buffer or buffer
  37 //       data/line class.
  38 const LINE_DATA_CHAR_INDEX = 1;
  39 const LINE_DATA_WIDTH_INDEX = 2;
  40
  41 const NON_BREAKING_SPACE_CHAR = String.fromCharCode(160);
  42 const ALL_NON_BREAKING_SPACE_REGEX = new RegExp(NON_BREAKING_SPACE_CHAR, 'g');
  43
  44 /**
  45  * Represents a position of a word on a line.
  46  */
  47 interface IWordPosition {
  48   start: number;
  49   length: number;
  50 }
  51
  52 /**
  53  * A selection mode, this drives how the selection behaves on mouse move.
  54  */
  55 enum SelectionMode {
  56   NORMAL,
  57   WORD,
  58   LINE
  59 }
  60
  61 /**
  62  * A class that manages the selection of the terminal. With help from
  63  * SelectionModel, SelectionManager handles with all logic associated with
  64  * dealing with the selection, including handling mouse interaction, wide
  65  * characters and fetching the actual text within the selection. Rendering is
  66  * not handled by the SelectionManager but a 'refresh' event is fired when the
  67  * selection is ready to be redrawn.
  68  */
  69 export class SelectionManager extends EventEmitter {
  70   protected _model: SelectionModel;
  71
  72   /**
  73    * The amount to scroll every drag scroll update (depends on how far the mouse
  74    * drag is above or below the terminal).
  75    */
  76   private _dragScrollAmount: number;
  77
  78   /**
  79    * The current selection mode.
  80    */
  81   private _activeSelectionMode: SelectionMode;
  82
  83   /**
  84    * A setInterval timer that is active while the mouse is down whose callback
  85    * scrolls the viewport when necessary.
  86    */
  87   private _dragScrollIntervalTimer: NodeJS.Timer;
  88
  89   /**
  90    * The animation frame ID used for refreshing the selection.
  91    */
  92   private _refreshAnimationFrame: number;
  93
  94   private _bufferTrimListener: any;
  95   private _mouseMoveListener: EventListener;
  96   private _mouseDownListener: EventListener;
  97   private _mouseUpListener: EventListener;
  98
  99   constructor(
 100     private _terminal: ITerminal,
 101     private _buffer: ICircularList<[number, string, number][]>,
 102     private _rowContainer: HTMLElement,
 103     private _charMeasure: CharMeasure
 104   ) {
 105     super();
 106     this._initListeners();
 107     this.enable();
 108
 109     this._model = new SelectionModel(_terminal);
 110     this._activeSelectionMode = SelectionMode.NORMAL;
 111   }
 112
 113   /**
 114    * Initializes listener variables.
 115    */
 116   private _initListeners() {
 117     this._bufferTrimListener = (amount: number) => this._onTrim(amount);
 118     this._mouseMoveListener = event => this._onMouseMove(<MouseEvent>event);
 119     this._mouseDownListener = event => this._onMouseDown(<MouseEvent>event);
 120     this._mouseUpListener = event => this._onMouseUp(<MouseEvent>event);
 121   }
 122
 123   /**
 124    * Disables the selection manager. This is useful for when terminal mouse
 125    * are enabled.
 126    */
 127   public disable() {
 128     this.clearSelection();
 129     this._buffer.off('trim', this._bufferTrimListener);
 130     this._rowContainer.removeEventListener('mousedown', this._mouseDownListener);
 131   }
 132
 133   /**
 134    * Enable the selection manager.
 135    */
 136   public enable() {
 137     // Only adjust the selection on trim, shiftElements is rarely used (only in
 138     // reverseIndex) and delete in a splice is only ever used when the same
 139     // number of elements was just added. Given this is could actually be
 140     // beneficial to leave the selection as is for these cases.
 141     this._buffer.on('trim', this._bufferTrimListener);
 142     this._rowContainer.addEventListener('mousedown', this._mouseDownListener);
 143   }
 144
 145   /**
 146    * Sets the active buffer, this should be called when the alt buffer is
 147    * switched in or out.
 148    * @param buffer The active buffer.
 149    */
 150   public setBuffer(buffer: ICircularList<[number, string, number][]>): void {
 151     this._buffer = buffer;
 152     this.clearSelection();
 153   }
 154
 155   public get selectionStart(): [number, number] { return this._model.finalSelectionStart; }
 156   public get selectionEnd(): [number, number] { return this._model.finalSelectionEnd; }
 157
 158   /**
 159    * Gets whether there is an active text selection.
 160    */
 161   public get hasSelection(): boolean {
 162     const start = this._model.finalSelectionStart;
 163     const end = this._model.finalSelectionEnd;
 164     if (!start || !end) {
 165       return false;
 166     }
 167     return start[0] !== end[0] || start[1] !== end[1];
 168   }
 169
 170   /**
 171    * Gets the text currently selected.
 172    */
 173   public get selectionText(): string {
 174     const start = this._model.finalSelectionStart;
 175     const end = this._model.finalSelectionEnd;
 176     if (!start || !end) {
 177       return '';
 178     }
 179
 180     // Get first row
 181     const startRowEndCol = start[1] === end[1] ? end[0] : null;
 182     let result: string[] = [];
 183     result.push(translateBufferLineToString(this._buffer.get(start[1]), true, start[0], startRowEndCol));
 184
 185     // Get middle rows
 186     for (let i = start[1] + 1; i <= end[1] - 1; i++) {
 187       const bufferLine = this._buffer.get(i);
 188       const lineText = translateBufferLineToString(bufferLine, true);
 189       if ((<any>bufferLine).isWrapped) {
 190         result[result.length - 1] += lineText;
 191       } else {
 192         result.push(lineText);
 193       }
 194     }
 195
 196     // Get final row
 197     if (start[1] !== end[1]) {
 198       const bufferLine = this._buffer.get(end[1]);
 199       const lineText = translateBufferLineToString(bufferLine, true, 0, end[0]);
 200       if ((<any>bufferLine).isWrapped) {
 201         result[result.length - 1] += lineText;
 202       } else {
 203         result.push(lineText);
 204       }
 205     }
 206
 207     // Format string by replacing non-breaking space chars with regular spaces
 208     // and joining the array into a multi-line string.
 209     const formattedResult = result.map(line => {
 210       return line.replace(ALL_NON_BREAKING_SPACE_REGEX, ' ');
 211     }).join(Browser.isMSWindows ? '\r\n' : '\n');
 212
 213     return formattedResult;
 214   }
 215
 216   /**
 217    * Clears the current terminal selection.
 218    */
 219   public clearSelection(): void {
 220     this._model.clearSelection();
 221     this._removeMouseDownListeners();
 222     this.refresh();
 223   }
 224
 225   /**
 226    * Queues a refresh, redrawing the selection on the next opportunity.
 227    * @param isNewSelection Whether the selection should be registered as a new
 228    * selection on Linux.
 229    */
 230   public refresh(isNewSelection?: boolean): void {
 231     // Queue the refresh for the renderer
 232     if (!this._refreshAnimationFrame) {
 233       this._refreshAnimationFrame = window.requestAnimationFrame(() => this._refresh());
 234     }
 235
 236     // If the platform is Linux and the refresh call comes from a mouse event,
 237     // we need to update the selection for middle click to paste selection.
 238     if (Browser.isLinux && isNewSelection) {
 239       const selectionText = this.selectionText;
 240       if (selectionText.length) {
 241         this.emit('newselection', this.selectionText);
 242       }
 243     }
 244   }
 245
 246   /**
 247    * Fires the refresh event, causing consumers to pick it up and redraw the
 248    * selection state.
 249    */
 250   private _refresh(): void {
 251     this._refreshAnimationFrame = null;
 252     this.emit('refresh', { start: this._model.finalSelectionStart, end: this._model.finalSelectionEnd });
 253   }
 254
 255   /**
 256    * Selects all text within the terminal.
 257    */
 258   public selectAll(): void {
 259     this._model.isSelectAllActive = true;
 260     this.refresh();
 261   }
 262
 263   /**
 264    * Handle the buffer being trimmed, adjust the selection position.
 265    * @param amount The amount the buffer is being trimmed.
 266    */
 267   private _onTrim(amount: number) {
 268     const needsRefresh = this._model.onTrim(amount);
 269     if (needsRefresh) {
 270       this.refresh();
 271     }
 272   }
 273
 274   /**
 275    * Gets the 0-based [x, y] buffer coordinates of the current mouse event.
 276    * @param event The mouse event.
 277    */
 278   private _getMouseBufferCoords(event: MouseEvent): [number, number] {
 279     const coords = Mouse.getCoords(event, this._rowContainer, this._charMeasure, this._terminal.cols, this._terminal.rows, true);
 280     // Convert to 0-based
 281     coords[0]--;
 282     coords[1]--;
 283     // Convert viewport coords to buffer coords
 284     coords[1] += this._terminal.buffer.ydisp;
 285     return coords;
 286   }
 287
 288   /**
 289    * Gets the amount the viewport should be scrolled based on how far out of the
 290    * terminal the mouse is.
 291    * @param event The mouse event.
 292    */
 293   private _getMouseEventScrollAmount(event: MouseEvent): number {
 294     let offset = Mouse.getCoordsRelativeToElement(event, this._rowContainer)[1];
 295     const terminalHeight = this._terminal.rows * this._charMeasure.height;
 296     if (offset >= 0 && offset <= terminalHeight) {
 297       return 0;
 298     }
 299     if (offset > terminalHeight) {
 300       offset -= terminalHeight;
 301     }
 302
 303     offset = Math.min(Math.max(offset, -DRAG_SCROLL_MAX_THRESHOLD), DRAG_SCROLL_MAX_THRESHOLD);
 304     offset /= DRAG_SCROLL_MAX_THRESHOLD;
 305     return (offset / Math.abs(offset)) + Math.round(offset * (DRAG_SCROLL_MAX_SPEED - 1));
 306   }
 307
 308   /**
 309    * Handles te mousedown event, setting up for a new selection.
 310    * @param event The mousedown event.
 311    */
 312   private _onMouseDown(event: MouseEvent) {
 313     // Only action the primary button
 314     if (event.button !== 0) {
 315       return;
 316     }
 317
 318     // Tell the browser not to start a regular selection
 319     event.preventDefault();
 320
 321     // Reset drag scroll state
 322     this._dragScrollAmount = 0;
 323
 324     if (event.shiftKey) {
 325       this._onShiftClick(event);
 326     } else {
 327       if (event.detail === 1) {
 328           this._onSingleClick(event);
 329       } else if (event.detail === 2) {
 330           this._onDoubleClick(event);
 331       } else if (event.detail === 3) {
 332           this._onTripleClick(event);
 333       }
 334     }
 335
 336     this._addMouseDownListeners();
 337     this.refresh(true);
 338   }
 339
 340   /**
 341    * Adds listeners when mousedown is triggered.
 342    */
 343   private _addMouseDownListeners(): void {
 344     // Listen on the document so that dragging outside of viewport works
 345     this._rowContainer.ownerDocument.addEventListener('mousemove', this._mouseMoveListener);
 346     this._rowContainer.ownerDocument.addEventListener('mouseup', this._mouseUpListener);
 347     this._dragScrollIntervalTimer = setInterval(() => this._dragScroll(), DRAG_SCROLL_INTERVAL);
 348   }
 349
 350   /**
 351    * Removes the listeners that are registered when mousedown is triggered.
 352    */
 353   private _removeMouseDownListeners(): void {
 354     this._rowContainer.ownerDocument.removeEventListener('mousemove', this._mouseMoveListener);
 355     this._rowContainer.ownerDocument.removeEventListener('mouseup', this._mouseUpListener);
 356     clearInterval(this._dragScrollIntervalTimer);
 357     this._dragScrollIntervalTimer = null;
 358   }
 359
 360   /**
 361    * Performs a shift click, setting the selection end position to the mouse
 362    * position.
 363    * @param event The mouse event.
 364    */
 365   private _onShiftClick(event: MouseEvent): void {
 366     if (this._model.selectionStart) {
 367       this._model.selectionEnd = this._getMouseBufferCoords(event);
 368     }
 369   }
 370
 371   /**
 372    * Performs a single click, resetting relevant state and setting the selection
 373    * start position.
 374    * @param event The mouse event.
 375    */
 376   private _onSingleClick(event: MouseEvent): void {
 377     this._model.selectionStartLength = 0;
 378     this._model.isSelectAllActive = false;
 379     this._activeSelectionMode = SelectionMode.NORMAL;
 380     this._model.selectionStart = this._getMouseBufferCoords(event);
 381     if (this._model.selectionStart) {
 382       this._model.selectionEnd = null;
 383       // If the mouse is over the second half of a wide character, adjust the
 384       // selection to cover the whole character
 385       const char = this._buffer.get(this._model.selectionStart[1])[this._model.selectionStart[0]];
 386       if (char[LINE_DATA_WIDTH_INDEX] === 0) {
 387         this._model.selectionStart[0]++;
 388       }
 389     }
 390   }
 391
 392   /**
 393    * Performs a double click, selecting the current work.
 394    * @param event The mouse event.
 395    */
 396   private _onDoubleClick(event: MouseEvent): void {
 397     const coords = this._getMouseBufferCoords(event);
 398     if (coords) {
 399       this._activeSelectionMode = SelectionMode.WORD;
 400       this._selectWordAt(coords);
 401     }
 402   }
 403
 404   /**
 405    * Performs a triple click, selecting the current line and activating line
 406    * select mode.
 407    * @param event The mouse event.
 408    */
 409   private _onTripleClick(event: MouseEvent): void {
 410     const coords = this._getMouseBufferCoords(event);
 411     if (coords) {
 412       this._activeSelectionMode = SelectionMode.LINE;
 413       this._selectLineAt(coords[1]);
 414     }
 415   }
 416
 417   /**
 418    * Handles the mousemove event when the mouse button is down, recording the
 419    * end of the selection and refreshing the selection.
 420    * @param event The mousemove event.
 421    */
 422   private _onMouseMove(event: MouseEvent) {
 423     // Record the previous position so we know whether to redraw the selection
 424     // at the end.
 425     const previousSelectionEnd = this._model.selectionEnd ? [this._model.selectionEnd[0], this._model.selectionEnd[1]] : null;
 426
 427     // Set the initial selection end based on the mouse coordinates
 428     this._model.selectionEnd = this._getMouseBufferCoords(event);
 429
 430     // Select the entire line if line select mode is active.
 431     if (this._activeSelectionMode === SelectionMode.LINE) {
 432       if (this._model.selectionEnd[1] < this._model.selectionStart[1]) {
 433         this._model.selectionEnd[0] = 0;
 434       } else {
 435         this._model.selectionEnd[0] = this._terminal.cols;
 436       }
 437     } else if (this._activeSelectionMode === SelectionMode.WORD) {
 438       this._selectToWordAt(this._model.selectionEnd);
 439     }
 440
 441     // Determine the amount of scrolling that will happen.
 442     this._dragScrollAmount = this._getMouseEventScrollAmount(event);
 443
 444     // If the cursor was above or below the viewport, make sure it's at the
 445     // start or end of the viewport respectively.
 446     if (this._dragScrollAmount > 0) {
 447       this._model.selectionEnd[0] = this._terminal.cols - 1;
 448     } else if (this._dragScrollAmount < 0) {
 449       this._model.selectionEnd[0] = 0;
 450     }
 451
 452     // If the character is a wide character include the cell to the right in the
 453     // selection. Note that selections at the very end of the line will never
 454     // have a character.
 455     if (this._model.selectionEnd[1] < this._buffer.length) {
 456       const char = this._buffer.get(this._model.selectionEnd[1])[this._model.selectionEnd[0]];
 457       if (char && char[2] === 0) {
 458         this._model.selectionEnd[0]++;
 459       }
 460     }
 461
 462     // Only draw here if the selection changes.
 463     if (!previousSelectionEnd ||
 464         previousSelectionEnd[0] !== this._model.selectionEnd[0] ||
 465         previousSelectionEnd[1] !== this._model.selectionEnd[1]) {
 466       this.refresh(true);
 467     }
 468   }
 469
 470   /**
 471    * The callback that occurs every DRAG_SCROLL_INTERVAL ms that does the
 472    * scrolling of the viewport.
 473    */
 474   private _dragScroll() {
 475     if (this._dragScrollAmount) {
 476       this._terminal.scrollDisp(this._dragScrollAmount, false);
 477       // Re-evaluate selection
 478       if (this._dragScrollAmount > 0) {
 479         this._model.selectionEnd = [this._terminal.cols - 1, this._terminal.buffer.ydisp + this._terminal.rows];
 480       } else {
 481         this._model.selectionEnd = [0, this._terminal.buffer.ydisp];
 482       }
 483       this.refresh();
 484     }
 485   }
 486
 487   /**
 488    * Handles the mouseup event, removing the mousedown listeners.
 489    * @param event The mouseup event.
 490    */
 491   private _onMouseUp(event: MouseEvent) {
 492     this._removeMouseDownListeners();
 493   }
 494
 495   /**
 496    * Converts a viewport column to the character index on the buffer line, the
 497    * latter takes into account wide characters.
 498    * @param coords The coordinates to find the 2 index for.
 499    */
 500   private _convertViewportColToCharacterIndex(bufferLine: any, coords: [number, number]): number {
 501     let charIndex = coords[0];
 502     for (let i = 0; coords[0] >= i; i++) {
 503       const char = bufferLine[i];
 504       if (char[LINE_DATA_WIDTH_INDEX] === 0) {
 505         charIndex--;
 506       }
 507     }
 508     return charIndex;
 509   }
 510
 511   public setSelection(col: number, row: number, length: number): void {
 512     this._model.clearSelection();
 513     this._removeMouseDownListeners();
 514     this._model.selectionStart = [col, row];
 515     this._model.selectionStartLength = length;
 516     this.refresh();
 517   }
 518
 519   /**
 520    * Gets positional information for the word at the coordinated specified.
 521    * @param coords The coordinates to get the word at.
 522    */
 523   private _getWordAt(coords: [number, number]): IWordPosition {
 524     const bufferLine = this._buffer.get(coords[1]);
 525     const line = translateBufferLineToString(bufferLine, false);
 526
 527     // Get actual index, taking into consideration wide characters
 528     let endIndex = this._convertViewportColToCharacterIndex(bufferLine, coords);
 529     let startIndex = endIndex;
 530
 531     // Record offset to be used later
 532     const charOffset = coords[0] - startIndex;
 533     let leftWideCharCount = 0;
 534     let rightWideCharCount = 0;
 535
 536     if (line.charAt(startIndex) === ' ') {
 537       // Expand until non-whitespace is hit
 538       while (startIndex > 0 && line.charAt(startIndex - 1) === ' ') {
 539         startIndex--;
 540       }
 541       while (endIndex < line.length && line.charAt(endIndex + 1) === ' ') {
 542         endIndex++;
 543       }
 544     } else {
 545       // Expand until whitespace is hit. This algorithm works by scanning left
 546       // and right from the starting position, keeping both the index format
 547       // (line) and the column format (bufferLine) in sync. When a wide
 548       // character is hit, it is recorded and the column index is adjusted.
 549       let startCol = coords[0];
 550       let endCol = coords[0];
 551       // Consider the initial position, skip it and increment the wide char
 552       // variable
 553       if (bufferLine[startCol][LINE_DATA_WIDTH_INDEX] === 0) {
 554         leftWideCharCount++;
 555         startCol--;
 556       }
 557       if (bufferLine[endCol][LINE_DATA_WIDTH_INDEX] === 2) {
 558         rightWideCharCount++;
 559         endCol++;
 560       }
 561       // Expand the string in both directions until a space is hit
 562       while (startIndex > 0 && !this._isCharWordSeparator(line.charAt(startIndex - 1))) {
 563         if (bufferLine[startCol - 1][LINE_DATA_WIDTH_INDEX] === 0) {
 564           // If the next character is a wide char, record it and skip the column
 565           leftWideCharCount++;
 566           startCol--;
 567         }
 568         startIndex--;
 569         startCol--;
 570       }
 571       while (endIndex + 1 < line.length && !this._isCharWordSeparator(line.charAt(endIndex + 1))) {
 572         if (bufferLine[endCol + 1][LINE_DATA_WIDTH_INDEX] === 2) {
 573           // If the next character is a wide char, record it and skip the column
 574           rightWideCharCount++;
 575           endCol++;
 576         }
 577         endIndex++;
 578         endCol++;
 579       }
 580     }
 581
 582     const start = startIndex + charOffset - leftWideCharCount;
 583     const length = Math.min(endIndex - startIndex + leftWideCharCount + rightWideCharCount + 1/*include endIndex char*/, this._terminal.cols);
 584     return {start, length};
 585   }
 586
 587   /**
 588    * Selects the word at the coordinates specified.
 589    * @param coords The coordinates to get the word at.
 590    */
 591   protected _selectWordAt(coords: [number, number]): void {
 592     const wordPosition = this._getWordAt(coords);
 593     this._model.selectionStart = [wordPosition.start, coords[1]];
 594     this._model.selectionStartLength = wordPosition.length;
 595   }
 596
 597   /**
 598    * Sets the selection end to the word at the coordinated specified.
 599    * @param coords The coordinates to get the word at.
 600    */
 601   private _selectToWordAt(coords: [number, number]): void {
 602     const wordPosition = this._getWordAt(coords);
 603     this._model.selectionEnd = [this._model.areSelectionValuesReversed() ? wordPosition.start : (wordPosition.start + wordPosition.length), coords[1]];
 604   }
 605
 606   /**
 607    * Gets whether the character is considered a word separator by the select
 608    * word logic.
 609    * @param char The character to check.
 610    */
 611   private _isCharWordSeparator(char: string): boolean {
 612     return WORD_SEPARATORS.indexOf(char) >= 0;
 613   }
 614
 615   /**
 616    * Selects the line specified.
 617    * @param line The line index.
 618    */
 619   protected _selectLineAt(line: number): void {
 620     this._model.selectionStart = [0, line];
 621     this._model.selectionStartLength = this._terminal.cols;
 622   }
 623 }