1/*
2 * Copyright (C) 2013 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26function Formatter(codeMirror, builder)
27{
28    console.assert(codeMirror);
29    console.assert(builder);
30
31    this._codeMirror = codeMirror;
32    this._builder = builder;
33
34    this._lastToken = null;
35    this._lastContent = "";
36};
37
38Formatter.prototype = {
39    constructor: Formatter,
40
41    // Public
42
43    format: function(from, to)
44    {
45        console.assert(this._builder.originalContent === null);
46        if (this._builder.originalContent !== null)
47            return;
48
49        var outerMode = this._codeMirror.getMode();
50        var content = this._codeMirror.getRange(from, to);
51        var state = CodeMirror.copyState(outerMode, this._codeMirror.getTokenAt(from).state);
52        this._builder.setOriginalContent(content);
53
54        var lineOffset = 0;
55        var lines = content.split("\n");
56        for (var i = 0; i < lines.length; ++i) {
57            var line = lines[i];
58            var startOfNewLine = true;
59            var firstTokenOnLine = true;
60            var stream = new CodeMirror.StringStream(line);
61            while (!stream.eol()) {
62                var innerMode = CodeMirror.innerMode(outerMode, state);
63                var token = outerMode.token(stream, state);
64                var isWhiteSpace = token === null && /^\s*$/.test(stream.current());
65                this._handleToken(innerMode.mode, token, state, stream, lineOffset + stream.start, isWhiteSpace, startOfNewLine, firstTokenOnLine);
66                stream.start = stream.pos;
67                startOfNewLine = false;
68                if (firstTokenOnLine && !isWhiteSpace)
69                    firstTokenOnLine = false;
70            }
71
72            if (firstTokenOnLine)
73                this._handleEmptyLine();
74
75            lineOffset += line.length + 1; // +1 for the "\n" removed in split.
76            this._handleLineEnding(lineOffset - 1); // -1 for the index of the "\n".
77        }
78
79        this._builder.finish();
80    },
81
82    // Private
83
84    _handleToken: function(mode, token, state, stream, originalPosition, isWhiteSpace, startOfNewLine, firstTokenOnLine)
85    {
86        // String content of the token.
87        var content = stream.current();
88
89        // Start of a new line. Insert a newline to be safe if code was not-ASI safe. These are collapsed.
90        if (startOfNewLine)
91            this._builder.appendNewline();
92
93        // Whitespace. Collapse to a single space.
94        if (isWhiteSpace) {
95            this._builder.appendSpace();
96            return;
97        }
98
99        // Avoid some hooks for content in comments.
100        var isComment = token && /\bcomment\b/.test(token);
101
102        if (mode.modifyStateForTokenPre)
103            mode.modifyStateForTokenPre(this._lastToken, this._lastContent, token, state, content, isComment);
104
105        // Should we remove the last newline?
106        if (this._builder.lastTokenWasNewline && mode.removeLastNewline(this._lastToken, this._lastContent, token, state, content, isComment, firstTokenOnLine))
107            this._builder.removeLastNewline();
108
109        // Add whitespace after the last token?
110        if (!this._builder.lastTokenWasWhitespace && mode.shouldHaveSpaceAfterLastToken(this._lastToken, this._lastContent, token, state, content, isComment))
111            this._builder.appendSpace();
112
113        // Add whitespace before this token?
114        if (!this._builder.lastTokenWasWhitespace && mode.shouldHaveSpaceBeforeToken(this._lastToken, this._lastContent, token, state, content, isComment))
115            this._builder.appendSpace();
116
117        // Should we dedent before this token?
118        var dedents = mode.dedentsBeforeToken(this._lastToken, this._lastContent, token, state, content, isComment);
119        while (dedents-- > 0)
120            this._builder.dedent();
121
122        // Should we add a newline before this token?
123        if (mode.newlineBeforeToken(this._lastToken, this._lastContent, token, state, content, isComment))
124            this._builder.appendNewline();
125
126        // Should we indent before this token?
127        if (mode.indentBeforeToken(this._lastToken, this._lastContent, token, state, content, isComment))
128            this._builder.indent();
129
130        // Append token.
131        this._builder.appendToken(content, originalPosition);
132
133        // Let the pretty printer update any state it keeps track of.
134        if (mode.modifyStateForTokenPost)
135            mode.modifyStateForTokenPost(this._lastToken, this._lastContent, token, state, content, isComment);
136
137        // Should we indent or dedent after this token?
138        if (!isComment && mode.indentAfterToken(this._lastToken, this._lastContent, token, state, content, isComment))
139            this._builder.indent();
140
141        // Should we add newlines after this token?
142        var newlines = mode.newlinesAfterToken(this._lastToken, this._lastContent, token, state, content, isComment);
143        if (newlines)
144            this._builder.appendMultipleNewlines(newlines);
145
146        // Record this token as the last token.
147        this._lastToken = token;
148        this._lastContent = content;
149    },
150
151    _handleEmptyLine: function()
152    {
153        // Preserve original whitespace only lines by adding a newline.
154        // However, don't do this if the builder just added multiple newlines.
155        if (!(this._builder.lastTokenWasNewline && this._builder.lastNewlineAppendWasMultiple))
156            this._builder.appendNewline(true);
157    },
158
159    _handleLineEnding: function(originalNewLinePosition)
160    {
161        // Record the original line ending.
162        this._builder.addOriginalLineEnding(originalNewLinePosition);
163    }
164};
165