gecko/browser/base/content/tabview/trench.js
2011-02-26 09:28:00 -05:00

696 lines
24 KiB
JavaScript

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is trench.js.
*
* The Initial Developer of the Original Code is
* the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Michael Yoshitaka Erlewine <mitcho@mitcho.com>
* Ian Gilman <ian@iangilman.com>
* Aza Raskin <aza@mozilla.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
// **********
// Title: trench.js
// ##########
// Class: Trench
//
// Class for drag-snapping regions; called "trenches" as they are long and narrow.
// Constructor: Trench
//
// Parameters:
// element - the DOM element for Item (GroupItem or TabItem) from which the trench is projected
// xory - either "x" or "y": whether the trench's <position> is along the x- or y-axis.
// In other words, if "x", the trench is vertical; if "y", the trench is horizontal.
// type - either "border" or "guide". Border trenches mark the border of an Item.
// Guide trenches extend out (unless they are intercepted) and act as "guides".
// edge - which edge of the Item that this trench corresponds to.
// Either "top", "left", "bottom", or "right".
function Trench(element, xory, type, edge) {
//----------
// Variable: id
// (integer) The id for the Trench. Set sequentially via <Trenches.nextId>
this.id = Trenches.nextId++;
// ---------
// Variables: Initial parameters
// element - (DOMElement)
// parentItem - <Item> which projects this trench; to be set with setParentItem
// xory - (string) "x" or "y"
// type - (string) "border" or "guide"
// edge - (string) "top", "left", "bottom", or "right"
this.el = element;
this.parentItem = null;
this.xory = xory; // either "x" or "y"
this.type = type; // "border" or "guide"
this.edge = edge; // "top", "left", "bottom", or "right"
this.$el = iQ(this.el);
//----------
// Variable: dom
// (array) DOM elements for visible reflexes of the Trench
this.dom = [];
//----------
// Variable: showGuide
// (boolean) Whether this trench will project a visible guide (dotted line) or not.
this.showGuide = false;
//----------
// Variable: active
// (boolean) Whether this trench is currently active or not.
// Basically every trench aside for those projected by the Item currently being dragged
// all become active.
this.active = false;
this.gutter = Items.defaultGutter;
//----------
// Variable: position
// (integer) position is the position that we should snap to.
this.position = 0;
//----------
// Variables: some Ranges
// range - (<Range>) explicit range; this is along the transverse axis
// minRange - (<Range>) the minimum active range
// activeRange - (<Range>) the currently active range
this.range = new Range(0,10000);
this.minRange = new Range(0,0);
this.activeRange = new Range(0,10000);
};
Trench.prototype = {
// ----------
// Function: toString
// Prints [Trench edge type (parentItem)] for debug use
toString: function Trench_toString() {
return "[Trench " + this.edge + " " + this.type +
(this.parentItem ? " (" + this.parentItem + ")" : "") +
"]";
},
//----------
// Variable: radius
// (integer) radius is how far away we should snap from
get radius() this.customRadius || Trenches.defaultRadius,
setParentItem: function Trench_setParentItem(item) {
if (!item.isAnItem) {
Utils.assert(false, "parentItem must be an Item");
return false;
}
this.parentItem = item;
return true;
},
//----------
// Function: setPosition
// set the trench's position.
//
// Parameters:
// position - (integer) px center position of the trench
// range - (<Range>) the explicit active range of the trench
// minRange - (<Range>) the minimum range of the trench
setPosition: function Trench_setPos(position, range, minRange) {
this.position = position;
var page = Items.getPageBounds(true);
// optionally, set the range.
if (Utils.isRange(range)) {
this.range = range;
} else {
this.range = new Range(0, (this.xory == 'x' ? page.height : page.width));
}
// if there's a minRange, set that too.
if (Utils.isRange(minRange))
this.minRange = minRange;
// set the appropriate bounds as a rect.
if (this.xory == "x") // vertical
this.rect = new Rect(this.position - this.radius, this.range.min, 2 * this.radius, this.range.extent);
else // horizontal
this.rect = new Rect(this.range.min, this.position - this.radius, this.range.extent, 2 * this.radius);
this.show(); // DEBUG
},
//----------
// Function: setActiveRange
// set the trench's currently active range.
//
// Parameters:
// activeRange - (<Range>)
setActiveRange: function Trench_setActiveRect(activeRange) {
if (!Utils.isRange(activeRange))
return false;
this.activeRange = activeRange;
if (this.xory == "x") { // horizontal
this.activeRect = new Rect(this.position - this.radius, this.activeRange.min, 2 * this.radius, this.activeRange.extent);
this.guideRect = new Rect(this.position, this.activeRange.min, 0, this.activeRange.extent);
} else { // vertical
this.activeRect = new Rect(this.activeRange.min, this.position - this.radius, this.activeRange.extent, 2 * this.radius);
this.guideRect = new Rect(this.activeRange.min, this.position, this.activeRange.extent, 0);
}
return true;
},
//----------
// Function: setWithRect
// Set the trench's position using the given rect. We know which side of the rect we should match
// because we've already recorded this information in <edge>.
//
// Parameters:
// rect - (<Rect>)
setWithRect: function Trench_setWithRect(rect) {
if (!Utils.isRect(rect))
Utils.error('argument must be Rect');
// First, calculate the range for this trench.
// Border trenches are always only active for the length of this range.
// Guide trenches, however, still use this value as its minRange.
if (this.xory == "x")
var range = new Range(rect.top - this.gutter, rect.bottom + this.gutter);
else
var range = new Range(rect.left - this.gutter, rect.right + this.gutter);
if (this.type == "border") {
// border trenches have a range, so set that too.
if (this.edge == "left")
this.setPosition(rect.left - this.gutter, range);
else if (this.edge == "right")
this.setPosition(rect.right + this.gutter, range);
else if (this.edge == "top")
this.setPosition(rect.top - this.gutter, range);
else if (this.edge == "bottom")
this.setPosition(rect.bottom + this.gutter, range);
} else if (this.type == "guide") {
// guide trenches have no range, but do have a minRange.
if (this.edge == "left")
this.setPosition(rect.left, false, range);
else if (this.edge == "right")
this.setPosition(rect.right, false, range);
else if (this.edge == "top")
this.setPosition(rect.top, false, range);
else if (this.edge == "bottom")
this.setPosition(rect.bottom, false, range);
}
},
//----------
// Function: show
//
// Show guide (dotted line), if <showGuide> is true.
//
// If <Trenches.showDebug> is true, we will draw the trench. Active portions are drawn with 0.5
// opacity. If <active> is false, the entire trench will be
// very translucent.
show: function Trench_show() { // DEBUG
if (this.active && this.showGuide) {
if (!this.dom.guideTrench)
this.dom.guideTrench = iQ("<div/>").addClass('guideTrench').css({id: 'guideTrench'+this.id});
var guideTrench = this.dom.guideTrench;
guideTrench.css(this.guideRect);
iQ("body").append(guideTrench);
} else {
if (this.dom.guideTrench) {
this.dom.guideTrench.remove();
delete this.dom.guideTrench;
}
}
if (!Trenches.showDebug) {
this.hide(true); // true for dontHideGuides
return;
}
if (!this.dom.visibleTrench)
this.dom.visibleTrench = iQ("<div/>")
.addClass('visibleTrench')
.addClass(this.type) // border or guide
.css({id: 'visibleTrench'+this.id});
var visibleTrench = this.dom.visibleTrench;
if (!this.dom.activeVisibleTrench)
this.dom.activeVisibleTrench = iQ("<div/>")
.addClass('activeVisibleTrench')
.addClass(this.type) // border or guide
.css({id: 'activeVisibleTrench'+this.id});
var activeVisibleTrench = this.dom.activeVisibleTrench;
if (this.active)
activeVisibleTrench.addClass('activeTrench');
else
activeVisibleTrench.removeClass('activeTrench');
visibleTrench.css(this.rect);
activeVisibleTrench.css(this.activeRect || this.rect);
iQ("body").append(visibleTrench);
iQ("body").append(activeVisibleTrench);
},
//----------
// Function: hide
// Hide the trench.
hide: function Trench_hide(dontHideGuides) {
if (this.dom.visibleTrench)
this.dom.visibleTrench.remove();
if (this.dom.activeVisibleTrench)
this.dom.activeVisibleTrench.remove();
if (!dontHideGuides && this.dom.guideTrench)
this.dom.guideTrench.remove();
},
//----------
// Function: rectOverlaps
// Given a <Rect>, compute whether it overlaps with this trench. If it does, return an
// adjusted ("snapped") <Rect>; if it does not overlap, simply return false.
//
// Note that simply overlapping is not all that is required to be affected by this function.
// Trenches can only affect certain edges of rectangles... for example, a "left"-edge guide
// trench should only affect left edges of rectangles. We don't snap right edges to left-edged
// guide trenches. For border trenches, the logic is a bit different, so left snaps to right and
// top snaps to bottom.
//
// Parameters:
// rect - (<Rect>) the rectangle in question
// stationaryCorner - which corner is stationary? by default, the top left.
// "topleft", "bottomleft", "topright", "bottomright"
// assumeConstantSize - (boolean) whether the rect's dimensions are sacred or not
// keepProportional - (boolean) if we are allowed to change the rect's size, whether the
// dimensions should scaled proportionally or not.
//
// Returns:
// false - if rect does not overlap with this trench
// newRect - (<Rect>) an adjusted version of rect, if it is affected by this trench
rectOverlaps: function Trench_rectOverlaps(rect,stationaryCorner,assumeConstantSize,keepProportional) {
var edgeToCheck;
if (this.type == "border") {
if (this.edge == "left")
edgeToCheck = "right";
else if (this.edge == "right")
edgeToCheck = "left";
else if (this.edge == "top")
edgeToCheck = "bottom";
else if (this.edge == "bottom")
edgeToCheck = "top";
} else { // if trench type is guide or barrier...
edgeToCheck = this.edge;
}
rect.adjustedEdge = edgeToCheck;
switch (edgeToCheck) {
case "left":
if (this.ruleOverlaps(rect.left, rect.yRange)) {
if (stationaryCorner.indexOf('right') > -1)
rect.width = rect.right - this.position;
rect.left = this.position;
return rect;
}
break;
case "right":
if (this.ruleOverlaps(rect.right, rect.yRange)) {
if (assumeConstantSize) {
rect.left = this.position - rect.width;
} else {
var newWidth = this.position - rect.left;
if (keepProportional)
rect.height = rect.height * newWidth / rect.width;
rect.width = newWidth;
}
return rect;
}
break;
case "top":
if (this.ruleOverlaps(rect.top, rect.xRange)) {
if (stationaryCorner.indexOf('bottom') > -1)
rect.height = rect.bottom - this.position;
rect.top = this.position;
return rect;
}
break;
case "bottom":
if (this.ruleOverlaps(rect.bottom, rect.xRange)) {
if (assumeConstantSize) {
rect.top = this.position - rect.height;
} else {
var newHeight = this.position - rect.top;
if (keepProportional)
rect.width = rect.width * newHeight / rect.height;
rect.height = newHeight;
}
return rect;
}
}
return false;
},
//----------
// Function: ruleOverlaps
// Computes whether the given "rule" (a line segment, essentially), given by the position and
// range arguments, overlaps with the current trench. Note that this function assumes that
// the rule and the trench are in the same direction: both horizontal, or both vertical.
//
// Parameters:
// position - (integer) a position in px
// range - (<Range>) the rule's range
ruleOverlaps: function Trench_ruleOverlaps(position, range) {
return (this.position - this.radius < position &&
position < this.position + this.radius &&
this.activeRange.overlaps(range));
},
//----------
// Function: adjustRangeIfIntercept
// Computes whether the given boundary (given as a position and its active range), perpendicular
// to the trench, intercepts the trench or not. If it does, it returns an adjusted <Range> for
// the trench. If not, it returns false.
//
// Parameters:
// position - (integer) the position of the boundary
// range - (<Range>) the target's range, on the trench's transverse axis
adjustRangeIfIntercept: function Trench_adjustRangeIfIntercept(position, range) {
if (this.position - this.radius > range.min && this.position + this.radius < range.max) {
var activeRange = new Range(this.activeRange);
// there are three ways this can go:
// 1. position < minRange.min
// 2. position > minRange.max
// 3. position >= minRange.min && position <= minRange.max
if (position < this.minRange.min) {
activeRange.min = Math.min(this.minRange.min,position);
} else if (position > this.minRange.max) {
activeRange.max = Math.max(this.minRange.max,position);
} else {
// this should be impossible because items can't overlap and we've already checked
// that the range intercepts.
}
return activeRange;
}
return false;
},
//----------
// Function: calculateActiveRange
// Computes and sets the <activeRange> for the trench, based on the <GroupItems> around.
// This makes it so trenches' active ranges don't extend through other groupItems.
calculateActiveRange: function Trench_calculateActiveRange() {
// set it to the default: just the range itself.
this.setActiveRange(this.range);
// only guide-type trenches need to set a separate active range
if (this.type != 'guide')
return;
var groupItems = GroupItems.groupItems;
var trench = this;
groupItems.forEach(function(groupItem) {
if (groupItem.isDragging) // floating groupItems don't block trenches
return;
if (trench.el == groupItem.container) // groupItems don't block their own trenches
return;
var bounds = groupItem.getBounds();
var activeRange = new Range();
if (trench.xory == 'y') { // if this trench is horizontal...
activeRange = trench.adjustRangeIfIntercept(bounds.left, bounds.yRange);
if (activeRange)
trench.setActiveRange(activeRange);
activeRange = trench.adjustRangeIfIntercept(bounds.right, bounds.yRange);
if (activeRange)
trench.setActiveRange(activeRange);
} else { // if this trench is vertical...
activeRange = trench.adjustRangeIfIntercept(bounds.top, bounds.xRange);
if (activeRange)
trench.setActiveRange(activeRange);
activeRange = trench.adjustRangeIfIntercept(bounds.bottom, bounds.xRange);
if (activeRange)
trench.setActiveRange(activeRange);
}
});
}
};
// ##########
// Class: Trenches
// Singelton for managing all <Trench>es.
var Trenches = {
// ---------
// Variables:
// nextId - (integer) a counter for the next <Trench>'s <Trench.id> value.
// showDebug - (boolean) whether to draw the <Trench>es or not.
// defaultRadius - (integer) the default radius for new <Trench>es.
// disabled - (boolean) whether trench-snapping is disabled or not.
nextId: 0,
showDebug: false,
defaultRadius: 10,
disabled: false,
// ---------
// Variables: snapping preferences; used to break ties in snapping.
// preferTop - (boolean) prefer snapping to the top to the bottom
// preferLeft - (boolean) prefer snapping to the left to the right
preferTop: true,
get preferLeft() { return !UI.rtl; },
trenches: [],
// ----------
// Function: toString
// Prints [Trenches count=count] for debug use
toString: function Trenches_toString() {
return "[Trenches count=" + this.trenches.length + "]";
},
// ---------
// Function: getById
// Return the specified <Trench>.
//
// Parameters:
// id - (integer)
getById: function Trenches_getById(id) {
return this.trenches[id];
},
// ---------
// Function: register
// Register a new <Trench> and returns the resulting <Trench> ID.
//
// Parameters:
// See the constructor <Trench.Trench>'s parameters.
//
// Returns:
// id - (int) the new <Trench>'s ID.
register: function Trenches_register(element, xory, type, edge) {
var trench = new Trench(element, xory, type, edge);
this.trenches[trench.id] = trench;
return trench.id;
},
// ---------
// Function: registerWithItem
// Register a whole set of <Trench>es using an <Item> and returns the resulting <Trench> IDs.
//
// Parameters:
// item - the <Item> to project trenches
// type - either "border" or "guide"
//
// Returns:
// ids - array of the new <Trench>es' IDs.
registerWithItem: function Trenches_registerWithItem(item, type) {
var container = item.container;
var ids = {};
ids.left = Trenches.register(container,"x",type,"left");
ids.right = Trenches.register(container,"x",type,"right");
ids.top = Trenches.register(container,"y",type,"top");
ids.bottom = Trenches.register(container,"y",type,"bottom");
this.getById(ids.left).setParentItem(item);
this.getById(ids.right).setParentItem(item);
this.getById(ids.top).setParentItem(item);
this.getById(ids.bottom).setParentItem(item);
return ids;
},
// ---------
// Function: unregister
// Unregister one or more <Trench>es.
//
// Parameters:
// ids - (integer) a single <Trench> ID or (array) a list of <Trench> IDs.
unregister: function Trenches_unregister(ids) {
if (!Array.isArray(ids))
ids = [ids];
var self = this;
ids.forEach(function(id) {
self.trenches[id].hide();
delete self.trenches[id];
});
},
// ---------
// Function: activateOthersTrenches
// Activate all <Trench>es other than those projected by the current element.
//
// Parameters:
// element - (DOMElement) the DOM element of the Item being dragged or resized.
activateOthersTrenches: function Trenches_activateOthersTrenches(element) {
this.trenches.forEach(function(t) {
if (t.el === element)
return;
if (t.parentItem && (t.parentItem.isAFauxItem ||
t.parentItem.isDragging ||
t.parentItem.isDropTarget))
return;
t.active = true;
t.calculateActiveRange();
t.show(); // debug
});
},
// ---------
// Function: disactivate
// After <activateOthersTrenches>, disactivates all the <Trench>es again.
disactivate: function Trenches_disactivate() {
this.trenches.forEach(function(t) {
t.active = false;
t.showGuide = false;
t.show();
});
},
// ---------
// Function: hideGuides
// Hide all guides (dotted lines) en masse.
hideGuides: function Trenches_hideGuides() {
this.trenches.forEach(function(t) {
t.showGuide = false;
t.show();
});
},
// ---------
// Function: snap
// Used to "snap" an object's bounds to active trenches and to the edge of the window.
// If the meta key is down (<Key.meta>), it will not snap but will still enforce the rect
// not leaving the safe bounds of the window.
//
// Parameters:
// rect - (<Rect>) the object's current bounds
// stationaryCorner - which corner is stationary? by default, the top left.
// "topleft", "bottomleft", "topright", "bottomright"
// assumeConstantSize - (boolean) whether the rect's dimensions are sacred or not
// keepProportional - (boolean) if we are allowed to change the rect's size, whether the
// dimensions should scaled proportionally or not.
//
// Returns:
// (<Rect>) - the updated bounds, if they were updated
// false - if the bounds were not updated
snap: function Trenches_snap(rect,stationaryCorner,assumeConstantSize,keepProportional) {
// hide all the guide trenches, because the correct ones will be turned on later.
Trenches.hideGuides();
var updated = false;
var updatedX = false;
var updatedY = false;
var snappedTrenches = {};
for (var i in this.trenches) {
var t = this.trenches[i];
if (!t.active || t.parentItem.isDropTarget)
continue;
// newRect will be a new rect, or false
var newRect = t.rectOverlaps(rect,stationaryCorner,assumeConstantSize,keepProportional);
if (newRect) { // if rectOverlaps returned an updated rect...
if (assumeConstantSize && updatedX && updatedY)
break;
if (assumeConstantSize && updatedX && (newRect.adjustedEdge == "left"||newRect.adjustedEdge == "right"))
continue;
if (assumeConstantSize && updatedY && (newRect.adjustedEdge == "top"||newRect.adjustedEdge == "bottom"))
continue;
rect = newRect;
updated = true;
// register this trench as the "snapped trench" for the appropriate edge.
snappedTrenches[newRect.adjustedEdge] = t;
// if updatedX, we don't need to update x any more.
if (newRect.adjustedEdge == "left" && this.preferLeft)
updatedX = true;
if (newRect.adjustedEdge == "right" && !this.preferLeft)
updatedX = true;
// if updatedY, we don't need to update x any more.
if (newRect.adjustedEdge == "top" && this.preferTop)
updatedY = true;
if (newRect.adjustedEdge == "bottom" && !this.preferTop)
updatedY = true;
}
}
if (updated) {
rect.snappedTrenches = snappedTrenches;
return rect;
}
return false;
},
// ---------
// Function: show
// <Trench.show> all <Trench>es.
show: function Trenches_show() {
this.trenches.forEach(function(t) {
t.show();
});
},
// ---------
// Function: toggleShown
// Toggle <Trenches.showDebug> and trigger <Trenches.show>
toggleShown: function Trenches_toggleShown() {
this.showDebug = !this.showDebug;
this.show();
}
};