// Copyright (C) 2016 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
(function() {
'use strict';
/**
* Possible CSS classes indicating the state of selection. Dynamically added/
* removed based on where the user clicks within the diff.
*/
var SelectionClass = {
COMMENT: 'selected-comment',
LEFT: 'selected-left',
RIGHT: 'selected-right',
};
Polymer({
is: 'gr-diff-selection',
properties: {
diff: Object,
_cachedDiffBuilder: Object,
_linesCache: {
type: Object,
value: function() { return {left: null, right: null}; },
},
},
listeners: {
'copy': '_handleCopy',
'down': '_handleDown',
},
attached: function() {
this.classList.add(SelectionClass.RIGHT);
},
get diffBuilder() {
if (!this._cachedDiffBuilder) {
this._cachedDiffBuilder =
Polymer.dom(this).querySelector('gr-diff-builder');
}
return this._cachedDiffBuilder;
},
_handleDown: function(e) {
var lineEl = this.diffBuilder.getLineElByChild(e.target);
if (!lineEl) {
return;
}
var commentSelected =
this._elementDescendedFromClass(e.target, 'gr-diff-comment');
var side = this.diffBuilder.getSideByLineEl(lineEl);
var targetClasses = [];
targetClasses.push(side === 'left' ?
SelectionClass.LEFT :
SelectionClass.RIGHT);
if (commentSelected) {
targetClasses.push(SelectionClass.COMMENT);
}
// Remove any selection classes that do not belong.
for (var key in SelectionClass) {
if (SelectionClass.hasOwnProperty(key)) {
var className = SelectionClass[key];
if (targetClasses.indexOf(className) === -1) {
this.classList.remove(SelectionClass[key]);
}
}
}
// Add new selection classes iff they are not already present.
for (var i = 0; i < targetClasses.length; i++) {
if (!this.classList.contains(targetClasses[i])) {
this.classList.add(targetClasses[i]);
}
}
},
_getCopyEventTarget: function(e) {
return Polymer.dom(e).rootTarget;
},
/**
* Utility function to determine whether an element is a descendant of
* another element with the particular className.
*
* @param {!Element} element
* @param {!string} className
* @return {boolean}
*/
_elementDescendedFromClass: function(element, className) {
while (!element.classList.contains(className)) {
if (!element.parentElement ||
element === this.diffBuilder.diffElement) {
return false;
}
element = element.parentElement;
}
return true;
},
_handleCopy: function(e) {
var commentSelected = false;
var target = this._getCopyEventTarget(e);
if (target.type === 'textarea') { return; }
if (!this._elementDescendedFromClass(target, 'diff-row')) { return; }
if (this.classList.contains(SelectionClass.COMMENT)) {
commentSelected = true;
}
var lineEl = this.diffBuilder.getLineElByChild(target);
if (!lineEl) {
return;
}
var side = this.diffBuilder.getSideByLineEl(lineEl);
var text = this._getSelectedText(side, commentSelected);
if (text) {
e.clipboardData.setData('Text', text);
e.preventDefault();
}
},
/**
* Get the text of the current window selection. If commentSelected is
* true, it returns only the text of comments within the selection.
* Otherwise it returns the text of the selected diff region.
*
* @param {!string} The side that is selected.
* @param {boolean} Whether or not a comment is selected.
* @return {string} The selected text.
*/
_getSelectedText: function(side, commentSelected) {
var sel = window.getSelection();
if (sel.rangeCount != 1) {
return; // No multi-select support yet.
}
if (commentSelected) {
return this._getCommentLines(sel, side);
}
var range = GrRangeNormalizer.normalize(sel.getRangeAt(0));
var startLineEl = this.diffBuilder.getLineElByChild(range.startContainer);
var endLineEl = this.diffBuilder.getLineElByChild(range.endContainer);
var startLineNum = parseInt(startLineEl.getAttribute('data-value'), 10);
var endLineNum = parseInt(endLineEl.getAttribute('data-value'), 10);
return this._getRangeFromDiff(startLineNum, range.startOffset, endLineNum,
range.endOffset, side);
},
/**
* Query the diff object for the selected lines.
*
* @param {int} startLineNum
* @param {int} startOffset
* @param {int} endLineNum
* @param {int} endOffset
* @param {!string} side The side that is currently selected.
* @return {string} The selected diff text.
*/
_getRangeFromDiff: function(startLineNum, startOffset, endLineNum,
endOffset, side) {
var lines = this._getDiffLines(side).slice(startLineNum - 1, endLineNum);
if (lines.length) {
lines[lines.length - 1] = lines[lines.length - 1]
.substring(0, endOffset);
lines[0] = lines[0].substring(startOffset);
}
return lines.join('\n');
},
/**
* Query the diff object for the lines from a particular side.
*
* @param {!string} side The side that is currently selected.
* @return {string[]} An array of strings indexed by line number.
*/
_getDiffLines: function(side) {
if (this._linesCache[side]) {
return this._linesCache[side];
}
var lines = [];
var chunk;
var key = side === 'left' ? 'a' : 'b';
for (var chunkIndex = 0;
chunkIndex < this.diff.content.length;
chunkIndex++) {
chunk = this.diff.content[chunkIndex];
if (chunk.ab) {
lines = lines.concat(chunk.ab);
} else if (chunk[key]) {
lines = lines.concat(chunk[key]);
}
}
this._linesCache[side] = lines;
return lines;
},
/**
* Query the diffElement for comments and check whether they lie inside the
* selection range.
*
* @param {!Selection} sel The selection of the window.
* @param {!string} side The side that is currently selected.
* @return {string} The selected comment text.
*/
_getCommentLines: function(sel, side) {
var range = GrRangeNormalizer.normalize(sel.getRangeAt(0));
var content = [];
// Query the diffElement for comments.
var messages = this.diffBuilder.diffElement.querySelectorAll(
'.side-by-side [data-side="' + side +
'"] .message *, .unified .message *');
for (var i = 0; i < messages.length; i++) {
var el = messages[i];
// Check if the comment element exists inside the selection.
if (sel.containsNode(el, true)) {
// Padded elements require newlines for accurate spacing.
if (el.parentElement.id === 'container' ||
el.parentElement.nodeName === 'BLOCKQUOTE') {
if (content.length && content[content.length - 1] !== '') {
content.push('');
}
}
if (el.id === 'output' &&
!this._elementDescendedFromClass(el, 'collapsed')) {
content.push(this._getTextContentForRange(el, sel, range));
}
}
}
return content.join('\n');
},
/**
* Given a DOM node, a selection, and a selection range, recursively get all
* of the text content within that selection.
* Using a domNode that isn't in the selection returns an empty string.
*
* @param {Element} domNode The root DOM node.
* @param {Selection} sel The selection.
* @param {Range} range The normalized selection range.
* @return {string} The text within the selection.
*/
_getTextContentForRange: function(domNode, sel, range) {
if (!sel.containsNode(domNode, true)) { return ''; }
var text = '';
if (domNode instanceof Text) {
text = domNode.textContent;
if (domNode === range.endContainer) {
text = text.substring(0, range.endOffset);
}
if (domNode === range.startContainer) {
text = text.substring(range.startOffset);
}
} else {
for (var i = 0; i < domNode.childNodes.length; i++) {
text += this._getTextContentForRange(domNode.childNodes[i],
sel, range);
}
}
return text;
},
});
})();