1/*
2 * [The "BSD licence"]
3 * Copyright (c) 2005-2008 Terence Parr
4 * All rights reserved.
5 *
6 * Conversion to C#:
7 * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33namespace Antlr.Runtime.Debug {
34
35    public class DebugTokenStream : ITokenStream {
36        protected IDebugEventListener dbg;
37        public ITokenStream input;
38        protected bool initialStreamState = true;
39
40        /** <summary>Track the last mark() call result value for use in rewind().</summary> */
41        protected int lastMarker;
42
43        public DebugTokenStream(ITokenStream input, IDebugEventListener dbg) {
44            this.input = input;
45            DebugListener = dbg;
46            // force TokenStream to get at least first valid token
47            // so we know if there are any hidden tokens first in the stream
48            input.LT(1);
49        }
50
51        #region Properties
52
53        public virtual int Index {
54            get {
55                return input.Index;
56            }
57        }
58
59        public virtual int Range {
60            get {
61                return input.Range;
62            }
63        }
64
65        public virtual IDebugEventListener DebugListener {
66            get {
67                return dbg;
68            }
69            set {
70                dbg = value;
71            }
72        }
73
74        #endregion
75
76        public virtual void Consume() {
77            if (initialStreamState) {
78                ConsumeInitialHiddenTokens();
79            }
80            int a = input.Index;
81            IToken t = input.LT(1);
82            input.Consume();
83            int b = input.Index;
84            dbg.ConsumeToken(t);
85            if (b > a + 1) {
86                // then we consumed more than one token; must be off channel tokens
87                for (int i = a + 1; i < b; i++) {
88                    dbg.ConsumeHiddenToken(input.Get(i));
89                }
90            }
91        }
92
93        /** <summary>Consume all initial off-channel tokens</summary> */
94        protected virtual void ConsumeInitialHiddenTokens() {
95            int firstOnChannelTokenIndex = input.Index;
96            for (int i = 0; i < firstOnChannelTokenIndex; i++) {
97                dbg.ConsumeHiddenToken(input.Get(i));
98            }
99            initialStreamState = false;
100        }
101
102        public virtual IToken LT(int i) {
103            if (initialStreamState) {
104                ConsumeInitialHiddenTokens();
105            }
106            dbg.LT(i, input.LT(i));
107            return input.LT(i);
108        }
109
110        public virtual int LA(int i) {
111            if (initialStreamState) {
112                ConsumeInitialHiddenTokens();
113            }
114            dbg.LT(i, input.LT(i));
115            return input.LA(i);
116        }
117
118        public virtual IToken Get(int i) {
119            return input.Get(i);
120        }
121
122        public virtual int Mark() {
123            lastMarker = input.Mark();
124            dbg.Mark(lastMarker);
125            return lastMarker;
126        }
127
128        public virtual void Rewind(int marker) {
129            dbg.Rewind(marker);
130            input.Rewind(marker);
131        }
132
133        public virtual void Rewind() {
134            dbg.Rewind();
135            input.Rewind(lastMarker);
136        }
137
138        public virtual void Release(int marker) {
139        }
140
141        public virtual void Seek(int index) {
142            // TODO: implement seek in dbg interface
143            // db.seek(index);
144            input.Seek(index);
145        }
146
147        public virtual int Count {
148            get {
149                return input.Count;
150            }
151        }
152
153        public virtual ITokenSource TokenSource {
154            get {
155                return input.TokenSource;
156            }
157        }
158
159        public virtual string SourceName {
160            get {
161                return TokenSource.SourceName;
162            }
163        }
164
165        public override string ToString() {
166            return input.ToString();
167        }
168
169        public virtual string ToString(int start, int stop) {
170            return input.ToString(start, stop);
171        }
172
173        public virtual string ToString(IToken start, IToken stop) {
174            return input.ToString(start, stop);
175        }
176    }
177}
178