net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpeclipse/phpeditor/php/PHPAutoIndentStrategy.java

   1 /**********************************************************************
   2  Copyright (c) 2000, 2002 IBM Corp. and others.
   3  All rights reserved. This program and the accompanying materials
   4  are made available under the terms of the Common Public License v1.0
   5  which accompanies this distribution, and is available at
   6  http://www.eclipse.org/legal/cpl-v10.html
   7
   8  Contributors:
   9  IBM Corporation - Initial implementation
  10  www.phpeclipse.de
  11  **********************************************************************/
  12 package net.sourceforge.phpeclipse.phpeditor.php;
  13
  14 import org.eclipse.jface.text.BadLocationException;
  15 import org.eclipse.jface.text.DefaultIndentLineAutoEditStrategy;
  16 import org.eclipse.jface.text.DocumentCommand;
  17 import org.eclipse.jface.text.IDocument;
  18
  19 /**
  20  * Auto indent strategy sensitive to brackets.
  21  */
  22 public class PHPAutoIndentStrategy extends DefaultIndentLineAutoEditStrategy {
  23
  24         public PHPAutoIndentStrategy() {
  25         }
  26
  27         /*
  28          * (non-Javadoc) Method declared on IAutoIndentStrategy
  29          */
  30         public void customizeDocumentCommand(IDocument d, DocumentCommand c) {
  31                 if (c.length == 0 && c.text != null && endsWithDelimiter(d, c.text))
  32                         smartIndentAfterNewLine(d, c);
  33                 else if ("}".equals(c.text)) {
  34                         smartInsertAfterBracket(d, c);
  35                 }
  36         }
  37
  38         /**
  39          * Returns whether or not the text ends with one of the given search
  40          * strings.
  41          */
  42         private boolean endsWithDelimiter(IDocument d, String txt) {
  43
  44                 String[] delimiters = d.getLegalLineDelimiters();
  45
  46                 for (int i = 0; i < delimiters.length; i++) {
  47                         if (txt.endsWith(delimiters[i]))
  48                                 return true;
  49                 }
  50
  51                 return false;
  52         }
  53
  54         /**
  55          * Returns the line number of the next bracket after end.
  56          *
  57          * @returns the line number of the next matching bracket after end
  58          * @param document -
  59          *            the document being parsed
  60          * @param line -
  61          *            the line to start searching back from
  62          * @param end -
  63          *            the end position to search back from
  64          * @param closingBracketIncrease -
  65          *            the number of brackets to skip
  66          */
  67         protected int findMatchingOpenBracket(IDocument document, int line,
  68                         int end, int closingBracketIncrease) throws BadLocationException {
  69
  70                 int start = document.getLineOffset(line);
  71                 int brackcount = getBracketCount(document, start, end, false)
  72                                 - closingBracketIncrease;
  73
  74                 // sum up the brackets counts of each line (closing brackets count
  75                 // negative,
  76                 // opening positive) until we find a line the brings the count to zero
  77                 while (brackcount < 0) {
  78                         line--;
  79                         if (line < 0) {
  80                                 return -1;
  81                         }
  82                         start = document.getLineOffset(line);
  83                         end = start + document.getLineLength(line) - 1;
  84                         brackcount += getBracketCount(document, start, end, false);
  85                 }
  86                 return line;
  87         }
  88
  89         /**
  90          * Returns the bracket value of a section of text. Closing brackets have a
  91          * value of -1 and open brackets have a value of 1.
  92          *
  93          * @returns the line number of the next matching bracket after end
  94          * @param document -
  95          *            the document being parsed
  96          * @param start -
  97          *            the start position for the search
  98          * @param end -
  99          *            the end position for the search
 100          * @param ignoreCloseBrackets -
 101          *            whether or not to ignore closing brackets in the count
 102          */
 103         private int getBracketCount(IDocument document, int start, int end,
 104                         boolean ignoreCloseBrackets) throws BadLocationException {
 105
 106                 int begin = start;
 107                 int bracketcount = 0;
 108                 while (begin < end) {
 109                         char curr = document.getChar(begin);
 110                         begin++;
 111                         switch (curr) {
 112                         case '/':
 113                                 if (begin < end) {
 114                                         char next = document.getChar(begin);
 115                                         if (next == '*') {
 116                                                 // a comment starts, advance to the comment end
 117                                                 begin = getCommentEnd(document, begin + 1, end);
 118                                         } else if (next == '/') {
 119                                                 // '//'-comment: nothing to do anymore on this line
 120                                                 begin = end;
 121                                         }
 122                                 }
 123                                 break;
 124                         case '*':
 125                                 if (begin < end) {
 126                                         char next = document.getChar(begin);
 127                                         if (next == '/') {
 128                                                 // we have been in a comment: forget what we read before
 129                                                 bracketcount = 0;
 130                                                 begin++;
 131                                         }
 132                                 }
 133                                 break;
 134                         case '{':
 135                                 bracketcount++;
 136                                 ignoreCloseBrackets = false;
 137                                 break;
 138                         case '}':
 139                                 if (!ignoreCloseBrackets) {
 140                                         bracketcount--;
 141                                 }
 142                                 break;
 143                         case '"':
 144                         case '\'':
 145                                 begin = getStringEnd(document, begin, end, curr);
 146                                 break;
 147                         default:
 148                         }
 149                 }
 150                 return bracketcount;
 151         }
 152
 153         /**
 154          * Returns the end position a comment starting at pos.
 155          *
 156          * @returns the end position a comment starting at pos
 157          * @param document -
 158          *            the document being parsed
 159          * @param position -
 160          *            the start position for the search
 161          * @param end -
 162          *            the end position for the search
 163          */
 164         private int getCommentEnd(IDocument document, int position, int end)
 165                         throws BadLocationException {
 166                 int currentPosition = position;
 167                 while (currentPosition < end) {
 168                         char curr = document.getChar(currentPosition);
 169                         currentPosition++;
 170                         if (curr == '*') {
 171                                 if (currentPosition < end
 172                                                 && document.getChar(currentPosition) == '/') {
 173                                         return currentPosition + 1;
 174                                 }
 175                         }
 176                 }
 177                 return end;
 178         }
 179
 180         /**
 181          * Returns the String at line with the leading whitespace removed.
 182          *
 183          * @returns the String at line with the leading whitespace removed.
 184          * @param document -
 185          *            the document being parsed
 186          * @param line -
 187          *            the line being searched
 188          */
 189         protected String getIndentOfLine(IDocument document, int line)
 190                         throws BadLocationException {
 191                 if (line > -1) {
 192                         int start = document.getLineOffset(line);
 193                         int end = start + document.getLineLength(line) - 1;
 194                         int whiteend = findEndOfWhiteSpace(document, start, end);
 195                         return document.get(start, whiteend - start);
 196                 } else {
 197                         return ""; //$NON-NLS-1$
 198                 }
 199         }
 200
 201         /**
 202          * Returns the position of the character in the document after position.
 203          *
 204          * @returns the next location of character.
 205          * @param document -
 206          *            the document being parsed
 207          * @param position -
 208          *            the position to start searching from
 209          * @param end -
 210          *            the end of the document
 211          * @param character -
 212          *            the character you are trying to match
 213          */
 214         private int getStringEnd(IDocument document, int position, int end,
 215                         char character) throws BadLocationException {
 216                 int currentPosition = position;
 217                 while (currentPosition < end) {
 218                         char currentCharacter = document.getChar(currentPosition);
 219                         currentPosition++;
 220                         if (currentCharacter == '\\') {
 221                                 // ignore escaped characters
 222                                 currentPosition++;
 223                         } else if (currentCharacter == character) {
 224                                 return currentPosition;
 225                         }
 226                 }
 227                 return end;
 228         }
 229
 230         /**
 231          * Set the indent of a new line based on the command provided in the
 232          * supplied document.
 233          *
 234          * @param document -
 235          *            the document being parsed
 236          * @param command -
 237          *            the command being performed
 238          */
 239         protected void smartIndentAfterNewLine(IDocument document,
 240                         DocumentCommand command) {
 241
 242                 int docLength = document.getLength();
 243                 if (command.offset == -1 || docLength == 0)
 244                         return;
 245
 246                 try {
 247                         int p = (command.offset == docLength ? command.offset - 1
 248                                         : command.offset);
 249                         int line = document.getLineOfOffset(p);
 250
 251                         StringBuffer buf = new StringBuffer(command.text);
 252                         if (command.offset < docLength
 253                                         && document.getChar(command.offset) == '}') {
 254                                 int indLine = findMatchingOpenBracket(document, line,
 255                                                 command.offset, 0);
 256                                 if (indLine == -1) {
 257                                         indLine = line;
 258                                 }
 259                                 buf.append(getIndentOfLine(document, indLine));
 260                         } else {
 261                                 int start = document.getLineOffset(line);
 262                                 int whiteend = findEndOfWhiteSpace(document, start,
 263                                                 command.offset);
 264                                 int offset = -1;
 265                                 // if (command.offset > 0 && command.offset < docLength &&
 266                                 // document.getChar(command.offset-1) == '{') {
 267                                 // offset = command.offset;
 268                                 // }
 269                                 buf.append(document.get(start, whiteend - start));
 270                                 if (getBracketCount(document, start, command.offset, true) > 0) {
 271                                         buf.append('\t');
 272                                 }
 273                                 // if (offset >= 0) {
 274                                 // buf.append('}');
 275                                 // }
 276                         }
 277                         command.text = buf.toString();
 278
 279                 } catch (BadLocationException excp) {
 280                         System.out.println(PHPEditorMessages
 281                                         .getString("AutoIndent.error.bad_location_1")); //$NON-NLS-1$
 282                 }
 283         }
 284
 285         /**
 286          * Set the indent of a bracket based on the command provided in the supplied
 287          * document.
 288          *
 289          * @param document -
 290          *            the document being parsed
 291          * @param command -
 292          *            the command being performed
 293          */
 294         protected void smartInsertAfterBracket(IDocument document,
 295                         DocumentCommand command) {
 296                 if (command.offset == -1 || document.getLength() == 0)
 297                         return;
 298
 299                 try {
 300                         int p = (command.offset == document.getLength() ? command.offset - 1
 301                                         : command.offset);
 302                         int line = document.getLineOfOffset(p);
 303                         int start = document.getLineOffset(line);
 304                         int whiteend = findEndOfWhiteSpace(document, start, command.offset);
 305
 306                         // shift only when line does not contain any text up to the closing
 307                         // bracket
 308                         if (whiteend == command.offset) {
 309                                 // evaluate the line with the opening bracket that matches out
 310                                 // closing bracket
 311                                 int indLine = findMatchingOpenBracket(document, line,
 312                                                 command.offset, 1);
 313                                 if (indLine != -1 && indLine != line) {
 314                                         // take the indent of the found line
 315                                         StringBuffer replaceText = new StringBuffer(
 316                                                         getIndentOfLine(document, indLine));
 317                                         // add the rest of the current line including the just added
 318                                         // close bracket
 319                                         replaceText.append(document.get(whiteend, command.offset
 320                                                         - whiteend));
 321                                         replaceText.append(command.text);
 322                                         // modify document command
 323                                         command.length = command.offset - start;
 324                                         command.offset = start;
 325                                         command.text = replaceText.toString();
 326                                 }
 327                         }
 328                 } catch (BadLocationException excp) {
 329                         System.out.println(PHPEditorMessages
 330                                         .getString("AutoIndent.error.bad_location_2")); //$NON-NLS-1$
 331                 }
 332         }
 333 }