Overleaf/services/web/public/js/ace/mouse/default_handlers.js

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define(function(require, exports, module) {
"use strict";

var dom = require("../lib/dom");
var event = require("../lib/event");
var useragent = require("../lib/useragent");

var DRAG_OFFSET = 0; // pixels

function DefaultHandlers(mouseHandler) {
    mouseHandler.$clickSelection = null;

    var editor = mouseHandler.editor;
    editor.setDefaultHandler("mousedown", this.onMouseDown.bind(mouseHandler));
    editor.setDefaultHandler("dblclick", this.onDoubleClick.bind(mouseHandler));
    editor.setDefaultHandler("tripleclick", this.onTripleClick.bind(mouseHandler));
    editor.setDefaultHandler("quadclick", this.onQuadClick.bind(mouseHandler));
    editor.setDefaultHandler("mousewheel", this.onMouseWheel.bind(mouseHandler));

    var exports = ["select", "startSelect", "selectEnd", "selectAllEnd", "selectByWordsEnd",
        "selectByLinesEnd", "dragWait", "dragWaitEnd", "focusWait"];

    exports.forEach(function(x) {
        mouseHandler[x] = this[x];
    }, this);

    mouseHandler.selectByLines = this.extendSelectionBy.bind(mouseHandler, "getLineRange");
    mouseHandler.selectByWords = this.extendSelectionBy.bind(mouseHandler, "getWordRange");
}

(function() {

    this.onMouseDown = function(ev) {
        var inSelection = ev.inSelection();
        var pos = ev.getDocumentPosition();
        this.mousedownEvent = ev;
        var editor = this.editor;

        var button = ev.getButton();
        if (button !== 0) {
            var selectionRange = editor.getSelectionRange();
            var selectionEmpty = selectionRange.isEmpty();

            if (selectionEmpty) {
                editor.moveCursorToPosition(pos);
                editor.selection.clearSelection();
            }

            // 2: contextmenu, 1: linux paste
            editor.textInput.onContextMenu(ev.domEvent);
            return; // stopping event here breaks contextmenu on ff mac
        }

        // if this click caused the editor to be focused should not clear the
        // selection
        if (inSelection && !editor.isFocused()) {
            editor.focus();
            if (this.$focusTimout && !this.$clickSelection && !editor.inMultiSelectMode) {
                this.mousedownEvent.time = (new Date()).getTime();
                this.setState("focusWait");
                this.captureMouse(ev);
                return;
            }
        }

        if (!inSelection || this.$clickSelection || ev.getShiftKey() || editor.inMultiSelectMode) {
            // Directly pick STATE_SELECT, since the user is not clicking inside
            // a selection.
            this.startSelect(pos);
        } else if (inSelection) {
            this.mousedownEvent.time = (new Date()).getTime();
            this.startSelect(pos);
        }
        this.captureMouse(ev);
        return ev.preventDefault();
    };

    this.startSelect = function(pos) {
        pos = pos || this.editor.renderer.screenToTextCoordinates(this.x, this.y);
        var editor = this.editor;
        // allow double/triple click handlers to change selection
        var shiftPressed = this.mousedownEvent.getShiftKey();
        setTimeout(function(){
            if (shiftPressed) {
                editor.selection.selectToPosition(pos);
            }
            else if (!this.$clickSelection) {
                editor.moveCursorToPosition(pos);
                editor.selection.clearSelection();
            }
        }.bind(this), 0);
        if (editor.renderer.scroller.setCapture) {
            editor.renderer.scroller.setCapture();
        }
        editor.setStyle("ace_selecting");
        this.setState("select");
    };

    this.select = function() {
        var anchor, editor = this.editor;
        var cursor = editor.renderer.screenToTextCoordinates(this.x, this.y);

        if (this.$clickSelection) {
            var cmp = this.$clickSelection.comparePoint(cursor);

            if (cmp == -1) {
                anchor = this.$clickSelection.end;
            } else if (cmp == 1) {
                anchor = this.$clickSelection.start;
            } else {
                var orientedRange = calcRangeOrientation(this.$clickSelection, cursor);
                cursor = orientedRange.cursor;
                anchor = orientedRange.anchor;
            }
            editor.selection.setSelectionAnchor(anchor.row, anchor.column);
        }
        editor.selection.selectToPosition(cursor);

        editor.renderer.scrollCursorIntoView();
    };

    this.extendSelectionBy = function(unitName) {
        var anchor, editor = this.editor;
        var cursor = editor.renderer.screenToTextCoordinates(this.x, this.y);
        var range = editor.selection[unitName](cursor.row, cursor.column);

        if (this.$clickSelection) {
            var cmpStart = this.$clickSelection.comparePoint(range.start);
            var cmpEnd = this.$clickSelection.comparePoint(range.end);

            if (cmpStart == -1 && cmpEnd <= 0) {
                anchor = this.$clickSelection.end;
                if (range.end.row != cursor.row || range.end.column != cursor.column)
                    cursor = range.start;
            } else if (cmpEnd == 1 && cmpStart >= 0) {
                anchor = this.$clickSelection.start;
                if (range.start.row != cursor.row || range.start.column != cursor.column)
                    cursor = range.end;
            } else if (cmpStart == -1 && cmpEnd == 1) {
                cursor = range.end;
                anchor = range.start;
            } else {
                var orientedRange = calcRangeOrientation(this.$clickSelection, cursor);
                cursor = orientedRange.cursor;
                anchor = orientedRange.anchor;
            }
            editor.selection.setSelectionAnchor(anchor.row, anchor.column);
        }
        editor.selection.selectToPosition(cursor);

        editor.renderer.scrollCursorIntoView();
    };

    this.selectEnd =
    this.selectAllEnd =
    this.selectByWordsEnd =
    this.selectByLinesEnd = function() {
        this.editor.unsetStyle("ace_selecting");
        if (this.editor.renderer.scroller.releaseCapture) {
            this.editor.renderer.scroller.releaseCapture();
        }
    };

    this.focusWait = function() {
        var distance = calcDistance(this.mousedownEvent.x, this.mousedownEvent.y, this.x, this.y);
        var time = (new Date()).getTime();

        if (distance > DRAG_OFFSET || time - this.mousedownEvent.time > this.$focusTimout)
            this.startSelect(this.mousedownEvent.getDocumentPosition());
    };

    this.onDoubleClick = function(ev) {
        var pos = ev.getDocumentPosition();
        var editor = this.editor;
        var session = editor.session;

        var range = session.getBracketRange(pos);
        if (range) {
            if (range.isEmpty()) {
                range.start.column--;
                range.end.column++;
            }
            this.$clickSelection = range;
            this.setState("select");
            return;
        }

        this.$clickSelection = editor.selection.getWordRange(pos.row, pos.column);
        this.setState("selectByWords");
    };

    this.onTripleClick = function(ev) {
        var pos = ev.getDocumentPosition();
        var editor = this.editor;

        this.setState("selectByLines");
        this.$clickSelection = editor.selection.getLineRange(pos.row);
    };

    this.onQuadClick = function(ev) {
        var editor = this.editor;

        editor.selectAll();
        this.$clickSelection = editor.getSelectionRange();
        this.setState("selectAll");
    };

    this.onMouseWheel = function(ev) {
        if (ev.getShiftKey() || ev.getAccelKey())
            return;
        var t = ev.domEvent.timeStamp;
        var dt = t - (this.$lastScrollTime||0);
        
        var editor = this.editor;
        var isScrolable = editor.renderer.isScrollableBy(ev.wheelX * ev.speed, ev.wheelY * ev.speed);
        if (isScrolable || dt < 200) {
            this.$lastScrollTime = t;
            editor.renderer.scrollBy(ev.wheelX * ev.speed, ev.wheelY * ev.speed);
            return ev.stop();
        }
    };

}).call(DefaultHandlers.prototype);

exports.DefaultHandlers = DefaultHandlers;

function calcDistance(ax, ay, bx, by) {
    return Math.sqrt(Math.pow(bx - ax, 2) + Math.pow(by - ay, 2));
}

function calcRangeOrientation(range, cursor) {
    if (range.start.row == range.end.row)
        var cmp = 2 * cursor.column - range.start.column - range.end.column;
    else if (range.start.row == range.end.row - 1 && !range.start.column && !range.end.column)
        var cmp = cursor.column - 4;
    else
        var cmp = 2 * cursor.row - range.start.row - range.end.row;

    if (cmp < 0)
        return {cursor: range.start, anchor: range.end};
    else
        return {cursor: range.end, anchor: range.start};
}

});