TextUtilities.cs


1:	// ITextSelection.cs
2:	// Copyright (c) 2001 Mike Krueger
3:	//
4:	// This program is free software; you can redistribute it and/or modify
5:	// it under the terms of the GNU General Public License as published by
6:	// the Free Software Foundation; either version 2 of the License, or
7:	// (at your option) any later version.
8:	//
9:	// This program is distributed in the hope that it will be useful,
10:	// but WITHOUT ANY WARRANTY; without even the implied warranty of
11:	// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12:	// GNU General Public License for more details.
13:	//
14:	// You should have received a copy of the GNU General Public License
15:	// along with this program; if not, write to the Free Software
16:	// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17:
18:	using System;
19:	using System.Diagnostics;
20:
21:	using Core.Properties;
22:	using SharpDevelop.Internal.Undo;
23:	using SharpDevelop.Gui.Edit; // for the ProgressEventHandler
24:
25:	namespace SharpDevelop.DefaultEditor.Text {
26:
27:	public sealed class TextUtilities
28:	{
29:	public static int GetFirstNonWSChar(IDocument document, int offset)
30:	{
31:	while (offset < document.TextLength && Char.IsWhiteSpace(document.GetCharAt(offset))) {
32:	++offset;
33:	}
34:	return offset;
35:	}
36:
37:	public static int FindWordEnd(IDocument document, int offset)
38:	{
39:	LineSegment line = document.GetLineSegmentOfOffset(offset);
40:	int endPos = line.Offset + line.Length;
41:	while (offset < endPos && Char.IsLetterOrDigit(document.GetCharAt(offset))) {
42:	++offset;
43:	}
44:
45:	return offset;
46:	}
47:
48:	public static int FindWordStart(IDocument document, int offset)
49:	{
50:	LineSegment line = document.GetLineSegmentOfOffset(offset);
51:
52:	while (offset > line.Offset && !Char.IsLetterOrDigit(document.GetCharAt(offset - 1))) {
53:	--offset;
54:	}
55:
56:	return offset;
57:	}
58:
59:	public static int FindNextWordEnd(IDocument document, int offset)
60:	{
61:	LineSegment line = document.GetLineSegmentOfOffset(offset);
62:	offset = FindWordEnd(document, offset);
63:
64:	int endPos = line.Offset + line.Length;
65:	while (offset < endPos && !Char.IsLetterOrDigit(document.GetCharAt(offset))) {
66:	++offset;
67:	}
68:	return offset;
69:	}
70:
71:	public static int FindPrevWordStart(IDocument document, int offset)
72:	{
73:	offset = FindWordStart(document, offset);
74:	LineSegment line = document.GetLineSegmentOfOffset(offset);
75:	while (offset > line.Offset && Char.IsLetterOrDigit(document.GetCharAt(offset - 1))) {
76:	--offset;
77:	}
78:	return offset;
79:	}
80:
81:	public static string GetLineAsString(IDocument document, int lineNumber)
82:	{
83:	LineSegment line = document.GetLineSegment(lineNumber);
84:	return document.GetText(line.Offset, line.Length);
85:	}
86:
87:	static bool ScanLineComment(IDocument document, int offset)
88:	{
89:	while (offset > 0 && offset < document.TextLength) {
90:	char ch = document.GetCharAt(offset);
91:	switch (ch) {
92:	case '\r':
93:	case '\n':
94:	return false;
95:	case '/':
96:	if (document.GetCharAt(offset + 1) == '/') {
97:	return true;
98:	}
99:	break;
100:	}
101:	--offset;
102:	}
103:	return false;
104:	}
105:
106:	public static int SearchBracketBackward(IDocument document, int offset, char openBracket, char closingBracket)
107:	{
108:	int brackets = -1;
109:
110:	bool inString = false;
111:	bool inChar = false;
112:
113:	bool blockComment = false;
114:
115:	while (offset > 0 && offset < document.TextLength) {
116:	char ch = document.GetCharAt(offset);
117:	switch (ch) {
118:	case '/':
119:	if (blockComment) {
120:	if (document.GetCharAt(offset + 1) == '*') {
121:	blockComment = false;
122:	}
123:	}
124:	if (!inString && !inChar && offset + 1 < document.TextLength) {
125:	if (document.GetCharAt(offset - 1) == '*') {
126:	blockComment = true;
127:	}
128:	}
129:	break;
130:	case '"':
131:	inString = !inString;
132:	break;
133:	case '\'':
134:	inChar = !inChar;
135:	break;
136:	default :
137:	if (ch == closingBracket) {
138:	if (!(inString \|\| inChar \|\| blockComment) && !ScanLineComment(document, offset)) {
139:	--brackets;
140:	}
141:	} else if (ch == openBracket) {
142:	if (!(inString \|\| inChar \|\| blockComment) && !ScanLineComment(document, offset)) {
143:	++brackets;
144:	if (brackets == 0) {
145:	return offset;
146:	}
147:	}
148:	}
149:	break;
150:	}
151:	--offset;
152:	}
153:	return - 1;
154:	}
155:
156:	public static int SearchBracketForward(IDocument document, int offset, char openBracket, char closingBracket)
157:	{
158:	int brackets = 1;
159:
160:	bool inString = false;
161:	bool inChar = false;
162:
163:	bool lineComment = false;
164:	bool blockComment = false;
165:
166:	if (offset >= 0) {
167:	while (offset < document.TextLength) {
168:	char ch = document.GetCharAt(offset);
169:	switch (ch) {
170:	case '\r':
171:	case '\n':
172:	lineComment = false;
173:	break;
174:	case '/':
175:	if (blockComment) {
176:	Debug.Assert(offset > 0);
177:	if (document.GetCharAt(offset - 1) == '*') {
178:	blockComment = false;
179:	}
180:	}
181:	if (!inString && !inChar && offset + 1 < document.TextLength) {
182:	if (!blockComment && document.GetCharAt(offset + 1) == '/') {
183:	lineComment = true;
184:	}
185:	if (!lineComment && document.GetCharAt(offset + 1) == '*') {
186:	blockComment = true;
187:	}
188:	}
189:	break;
190:	case '"':
191:	inString = !inString;
192:	break;
193:	case '\'':
194:	inChar = !inChar;
195:	break;
196:	default :
197:	if (ch == openBracket) {
198:	if (!(inString \|\| inChar \|\| lineComment \|\| blockComment)) {
199:	++brackets;
200:	}
201:	} else if (ch == closingBracket) {
202:	if (!(inString \|\| inChar \|\| lineComment \|\| blockComment)) {
203:	--brackets;
204:	if (brackets == 0) {
205:	return offset;
206:	}
207:	}
208:	}
209:	break;
210:	}
211:	++offset;
212:	}
213:	}
214:	return -1;
215:	}
216:
217:	/// <summary>
218:	/// Returns true, if the line lineNumber is empty or filled with whitespaces.
219:	/// </summary>
220:	public static bool IsEmptyLine(IDocument document, int lineNumber)
221:	{
222:	return IsEmptyLine(document, document.GetLineSegment(lineNumber));
223:	}
224:
225:	/// <summary>
226:	/// Returns true, if the line lineNumber is empty or filled with whitespaces.
227:	/// </summary>
228:	public static bool IsEmptyLine(IDocument document, LineSegment line)
229:	{
230:	for (int i = line.Offset; i < line.Offset + line.Length; ++i) {
231:	char ch = document.GetCharAt(i);
232:	if (!Char.IsWhiteSpace(ch)) {
233:	return false;
234:	}
235:	}
236:	return true;
237:	}
238:	}
239:	}