TextEditorHighlighter.js revision cad810f21b803229eb11403f9209855525a25d57 
1/*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 * Copyright (C) 2009 Apple Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met:
8 *
9 *     * Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *     * Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following disclaimer
13 * in the documentation and/or other materials provided with the
14 * distribution.
15 *     * Neither the name of Google Inc. nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32WebInspector.TextEditorHighlighter = function(textModel, damageCallback)
33{
34    this._textModel = textModel;
35    this._tokenizer = WebInspector.SourceTokenizer.Registry.getInstance().getTokenizer("text/html");
36    this._damageCallback = damageCallback;
37    this.reset();
38}
39
40WebInspector.TextEditorHighlighter.prototype = {
41    set mimeType(mimeType)
42    {
43        var tokenizer = WebInspector.SourceTokenizer.Registry.getInstance().getTokenizer(mimeType);
44        if (tokenizer) {
45            this._tokenizer = tokenizer;
46            this._tokenizerCondition = this._tokenizer.initialCondition;
47        }
48    },
49
50    reset: function()
51    {
52        this._lastHighlightedLine = 0;
53        this._lastHighlightedColumn = 0;
54        this._tokenizerCondition = this._tokenizer.initialCondition;
55    },
56
57    highlight: function(endLine)
58    {
59        // First check if we have work to do.
60        if (endLine <= this._lastHighlightedLine)
61            return;
62
63        this._requestedEndLine = endLine;
64
65        if (this._highlightTimer) {
66            // There is a timer scheduled, it will catch the new job based on the new endLine set.
67            return;
68        }
69
70        // Do small highlight synchronously. This will provide instant highlight on PageUp / PageDown, gentle scrolling.
71        this._highlightInChunks(endLine);
72
73        // Schedule tail highlight if necessary.
74        if (this._lastHighlightedLine < endLine)
75            this._highlightTimer = setTimeout(this._highlightInChunks.bind(this, endLine), 100);
76    },
77
78    _highlightInChunks: function(endLine)
79    {
80        delete this._highlightTimer;
81
82        // First we always check if we have work to do. Could be that user scrolled back and we can quit.
83        if (this._requestedEndLine <= this._lastHighlightedLine)
84            return;
85
86        if (this._requestedEndLine !== endLine) {
87            // User keeps updating the job in between of our timer ticks. Just reschedule self, don't eat CPU (they must be scrolling).
88            this._highlightTimer = setTimeout(this._highlightInChunks.bind(this, this._requestedEndLine), 100);
89            return;
90        }
91
92        this._highlightLines(this._requestedEndLine);
93
94        // Schedule tail highlight if necessary.
95        if (this._lastHighlightedLine < this._requestedEndLine)
96            this._highlightTimer = setTimeout(this._highlightInChunks.bind(this, this._requestedEndLine), 10);
97    },
98
99    _highlightLines: function(endLine)
100    {
101        // Tokenizer is stateless and reused accross viewers, restore its condition before highlight and save it after.
102        this._tokenizer.condition = this._tokenizerCondition;
103        var tokensCount = 0;
104        for (var lineNumber = this._lastHighlightedLine; lineNumber < endLine; ++lineNumber) {
105            var line = this._textModel.line(lineNumber);
106            this._tokenizer.line = line;
107            var attributes = this._textModel.getAttribute(lineNumber, "highlight") || {};
108
109            // Highlight line.
110            do {
111                var newColumn = this._tokenizer.nextToken(this._lastHighlightedColumn);
112                var tokenType = this._tokenizer.tokenType;
113                if (tokenType)
114                    attributes[this._lastHighlightedColumn] = { length: newColumn - this._lastHighlightedColumn, tokenType: tokenType, subTokenizer: this._tokenizer.subTokenizer };
115                this._lastHighlightedColumn = newColumn;
116                if (++tokensCount > 1000)
117                    break;
118            } while (this._lastHighlightedColumn < line.length)
119
120            this._textModel.setAttribute(lineNumber, "highlight", attributes);
121            if (this._lastHighlightedColumn < line.length) {
122                // Too much work for single chunk - exit.
123                break;
124            } else
125                this._lastHighlightedColumn = 0;
126        }
127
128        this._damageCallback(this._lastHighlightedLine, lineNumber);
129        this._tokenizerCondition = this._tokenizer.condition;
130        this._lastHighlightedLine = lineNumber;
131    }
132}
133