private static int ScanLineStart(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset)
{
for (int i = offset - 1; i > 0; --i)
{
if (document.GetCharAt(i) == '\n')
{
return(i + 1);
}
}
return(0);
}
private static int QuickSearchBracketForward(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset, char openBracket, char closingBracket)
{
int brackets = 1;
// try "quick find" - find the matching bracket if there is no string/comment in the way
for (int i = offset; i < document.TextLength; ++i)
{
char ch = document.GetCharAt(i);
if (ch == openBracket)
{
++brackets;
}
else if (ch == closingBracket)
{
--brackets;
if (brackets == 0)
{
return(i);
}
}
else if (ch == '"')
{
break;
}
else if (ch == '\'')
{
break;
}
else if (ch == '/' && i > 0)
{
if (document.GetCharAt(i - 1) == '/')
{
break;
}
}
else if (ch == '-' && i > 0)
{
if (document.GetCharAt(i - 1) == '-')
{
break;
}
}
else if (ch == '*' && i > 0)
{
if (document.GetCharAt(i - 1) == '/')
{
break;
}
}
}
return(-1);
}
/// <summary>
/// Class constructor
/// </summary>
/// <param name="document"></param>
/// <param name="offset"></param>
/// <returns></returns>
public BracketSearchResult SearchBracket(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset)
{
if (document == null)
{
throw new ArgumentNullException(nameof(document));
}
if (offset > 0)
{
char c = document.GetCharAt(offset - 1);
int index = openingBrackets.IndexOf(c);
int otherOffset = -1;
if (index > -1)
{
otherOffset = SearchBracketForward(document, offset, openingBrackets[index], closingBrackets[index]);
}
index = closingBrackets.IndexOf(c);
if (index > -1)
{
otherOffset = SearchBracketBackward(document, offset - 1, openingBrackets[index], closingBrackets[index]);
}
// if we found the other bracket
if (otherOffset > -1)
{
return(new BracketSearchResult(Math.Min(offset - 1, otherOffset), 1,
Math.Max(offset - 1, otherOffset), 1));
}
if (otherOffset == -2) // in string
{
return(null);
}
// if we are on a bracket, but did not find a match
if (index >= 0 || openingBrackets.IndexOf(c) >= 0)
{
return(new BracketSearchResult(offset - 1, 1, 0, 0));
}
}
return(null);
}
/// <summary>
/// Gets the type of code at offset.<br/>
/// 0 = Code,<br/>
/// 1 = Comment,<br/>
/// 2 = String<br/>
/// Block comments and multiline strings are not supported.
/// </summary>
//TODO: this should return an enum not an int
private static int GetStartType(ICSharpCode.AvalonEdit.Document.ITextSource document, int linestart, int offset)
{
bool inString = false;
bool inChar = false;
bool verbatim = false;
int result = 0;
for (int i = linestart; i < offset; i++)
{
switch (document.GetCharAt(i))
{
case '/':
if (!inString && !inChar && i + 1 < document.TextLength)
{
if (document.GetCharAt(i + 1) == '/')
{
result = 1;
}
}
break;
case '-':
if (!inString && !inChar && i + 1 < document.TextLength)
{
if (document.GetCharAt(i + 1) == '-')
{
result = 1;
}
}
break;
case '"':
if (!inChar)
{
if (inString && verbatim)
{
if (i + 1 < document.TextLength && document.GetCharAt(i + 1) == '"')
{
++i; // skip escaped quote
inString = false; // let the string go on
}
else
{
verbatim = false;
}
}
else if (!inString && i > 0 && document.GetCharAt(i - 1) == '@')
{
verbatim = true;
}
inString = !inString;
}
break;
case '\'':
if (!inString)
{
inChar = !inChar;
}
break;
case '\\':
if ((inString && !verbatim) || inChar)
{
++i; // skip next character
}
break;
}
}
return((inString || inChar) ? 2 : result);
}
private static int SearchBracketForward(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset, char openBracket, char closingBracket)
{
bool inString = false;
bool inChar = false;
bool verbatim = false;
bool lineComment = false;
bool blockComment = false;
if (offset < 0)
{
return(-1);
}
// first try "quick find" - find the matching bracket if there is no string/comment in the way
int quickResult = QuickSearchBracketForward(document, offset, openBracket, closingBracket);
if (quickResult >= 0)
{
return(quickResult);
}
// we need to parse the line from the beginning, so get the line start position
int linestart = ScanLineStart(document, offset);
// we need to know where offset is - in a string/comment or in normal code?
// ignore cases where offset is in a block comment
int starttype = GetStartType(document, linestart, offset);
if (starttype != 0)
{
return(-1); // start position is in a comment/string
}
int brackets = 1;
while (offset < document.TextLength)
{
char ch = document.GetCharAt(offset);
switch (ch)
{
case '\r':
case '\n':
lineComment = false;
inChar = false;
if (!verbatim)
{
inString = false;
}
break;
case '-':
if (!inString && !blockComment && document.GetCharAt(offset - 1) == '-')
{
lineComment = true;
}
break;
case '/':
if (blockComment)
{
Debug.Assert(offset > 0);
if (document.GetCharAt(offset - 1) == '*')
{
blockComment = false;
}
}
if (!inString && !inChar && offset + 1 < document.TextLength)
{
if (!blockComment && document.GetCharAt(offset + 1) == '/')
{
lineComment = true;
}
if (!lineComment && document.GetCharAt(offset + 1) == '*')
{
blockComment = true;
}
}
break;
case '"':
if (!(inChar || lineComment || blockComment))
{
if (inString && verbatim)
{
if (offset + 1 < document.TextLength && document.GetCharAt(offset + 1) == '"')
{
++offset; // skip escaped quote
inString = false; // let the string go
}
else
{
verbatim = false;
}
}
else if (!inString && offset > 0 && document.GetCharAt(offset - 1) == '@')
{
verbatim = true;
}
inString = !inString;
}
break;
case '\'':
if (!(inString || lineComment || blockComment))
{
inChar = !inChar;
}
break;
case '\\':
if ((inString && !verbatim) || inChar)
{
++offset; // skip next character
}
break;
default:
if (ch == openBracket)
{
if (!(inString || inChar || lineComment || blockComment))
{
++brackets;
}
}
else if (ch == closingBracket)
{
if (!(inString || inChar || lineComment || blockComment))
{
--brackets;
if (brackets == 0)
{
return(offset);
}
}
}
break;
}
++offset;
}
if (inString || inChar || lineComment || blockComment)
{
return(-2);
}
return(-1);
}
private static int SearchBracketBackward(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset, char openBracket, char closingBracket)
{
if (offset >= document.TextLength)
{
return(-1);
}
// this method parses a DAX document backwards to find the matching bracket
// first try "quick find" - find the matching bracket if there is no string/comment in the way
int quickResult = QuickSearchBracketBackward(document, offset, openBracket, closingBracket);
if (quickResult >= 0)
{
return(quickResult);
}
// we need to parse the line from the beginning, so get the line start position
int linestart = ScanLineStart(document, offset + 1);
// we need to know where offset is - in a string/comment or in normal code?
// ignore cases where offset is in a block comment
int starttype = GetStartType(document, linestart, offset + 1);
if (starttype == 1)
{
return(-2); // start position is in a comment
}
// I don't see any possibility to parse a DAX document backwards...
// We have to do it forwards and push all bracket positions on a stack.
Stack <int> bracketStack = new Stack <int>();
bool blockComment = false;
bool lineComment = false;
bool inChar = false;
bool inString = false;
bool verbatim = false;
for (int i = 0; i < offset; ++i)
{
char ch = document.GetCharAt(i);
switch (ch)
{
case '\r':
case '\n':
lineComment = false;
inChar = false;
if (!verbatim)
{
inString = false;
}
break;
case '-':
if (!inString && !inChar && !blockComment && i != document.TextLength)
{
if (i > 0)
{
if (document.GetCharAt(i - 1) == '-')
{
lineComment = true;
}
}
}
break;
case '/':
if (blockComment)
{
Debug.Assert(i > 0);
if (document.GetCharAt(i - 1) == '*')
{
blockComment = false;
}
}
if (!inString && !inChar && i + 1 < document.TextLength)
{
if (!blockComment && document.GetCharAt(i + 1) == '/')
{
lineComment = true;
}
if (!lineComment && document.GetCharAt(i + 1) == '*')
{
blockComment = true;
}
}
break;
case '"':
if (!(inChar || lineComment || blockComment))
{
if (inString && verbatim)
{
if (i + 1 < document.TextLength && document.GetCharAt(i + 1) == '"')
{
++i; // skip escaped quote
inString = false; // let the string go
}
else
{
verbatim = false;
}
}
else if (!inString && offset > 0 && document.GetCharAt(i - 1) == '@')
{
verbatim = true;
}
inString = !inString;
}
break;
case '\'':
if (!(inString || lineComment || blockComment))
{
inChar = !inChar;
}
break;
case '\\':
if ((inString && !verbatim) || inChar)
{
++i; // skip next character
}
break;
default:
if (ch == openBracket)
{
if (!(inString || inChar || lineComment || blockComment))
{
bracketStack.Push(i);
}
}
else if (ch == closingBracket)
{
if (!(inString || inChar || lineComment || blockComment))
{
if (bracketStack.Count > 0)
{
bracketStack.Pop();
}
}
}
break;
}
}
if (bracketStack.Count > 0 && !inString && !inChar && !lineComment && !blockComment)
{
return((int)bracketStack.Pop());
}
if (inString || inChar || lineComment || blockComment)
{
return(-2);
}
return(-1);
}
public BracketSearchResult SearchBracket(ICSharpCode.AvalonEdit.Document.ITextSource document, int offset)
{
return(null);
}