/// <summary>
/// Constructor that allows the caller to specify file selection criteria.
/// </summary>
///
/// <remarks>
/// <para>
/// This constructor allows the caller to specify a set of criteria for selection of files.
/// </para>
///
/// <para>
/// See <see cref="FileSelector.SelectionCriteria"/> for a description of the syntax of
/// the selectionCriteria string.
/// </para>
/// </remarks>
///
/// <param name="selectionCriteria">The criteria for file selection.</param>
public FileSelector(String selectionCriteria)
{
if (!String.IsNullOrEmpty(selectionCriteria))
{
_Criterion = _ParseCriterion(selectionCriteria);
}
}
private static SelectionCriterion _ParseCriterion(String s)
{
if (s == null)
{
return(null);
}
// shorthand for filename glob
if (s.IndexOf(" ") == -1)
{
s = "name = " + s;
}
// inject spaces after open paren and before close paren
string[] prPairs = { @"\((\S)", "( $1", @"(\S)\)", "$1 )", };
for (int i = 0; i + 1 < prPairs.Length; i += 2)
{
Regex rgx = new Regex(prPairs[i]);
s = rgx.Replace(s, prPairs[i + 1]);
}
// split the expression into tokens
string[] tokens = s.Trim().Split(' ', '\t');
if (tokens.Length < 3)
{
throw new ArgumentException(s);
}
SelectionCriterion current = null;
LogicalConjunction pendingConjunction = LogicalConjunction.NONE;
ParseState state;
var stateStack = new System.Collections.Generic.Stack <ParseState>();
var critStack = new System.Collections.Generic.Stack <SelectionCriterion>();
stateStack.Push(ParseState.Start);
for (int i = 0; i < tokens.Length; i++)
{
switch (tokens[i].ToLower())
{
case "and":
case "xor":
case "or":
state = stateStack.Peek();
if (state != ParseState.CriterionDone)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
if (tokens.Length <= i + 3)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
pendingConjunction = (LogicalConjunction)Enum.Parse(typeof(LogicalConjunction), tokens[i].ToUpper());
current = new CompoundCriterion {
Left = current, Right = null, Conjunction = pendingConjunction
};
stateStack.Push(state);
stateStack.Push(ParseState.ConjunctionPending);
critStack.Push(current);
break;
case "(":
state = stateStack.Peek();
if (state != ParseState.Start && state != ParseState.ConjunctionPending && state != ParseState.OpenParen)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
if (tokens.Length <= i + 4)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
stateStack.Push(ParseState.OpenParen);
break;
case ")":
state = stateStack.Pop();
if (stateStack.Peek() != ParseState.OpenParen)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
stateStack.Pop();
stateStack.Push(ParseState.CriterionDone);
break;
case "atime":
case "ctime":
case "mtime":
if (tokens.Length <= i + 2)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
DateTime t;
try
{
t = DateTime.ParseExact(tokens[i + 2], "yyyy-MM-dd-HH:mm:ss", null);
}
catch (FormatException)
{
t = DateTime.ParseExact(tokens[i + 2], "yyyy-MM-dd", null);
}
t = DateTime.SpecifyKind(t, DateTimeKind.Local).ToUniversalTime();
current = new TimeCriterion
{
Which = (WhichTime)Enum.Parse(typeof(WhichTime), tokens[i]),
Operator = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]),
Time = t
};
i += 2;
stateStack.Push(ParseState.CriterionDone);
break;
case "length":
case "size":
if (tokens.Length <= i + 2)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
Int64 sz = 0;
string v = tokens[i + 2];
if (v.ToUpper().EndsWith("K"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024;
}
else if (v.ToUpper().EndsWith("KB"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024;
}
else if (v.ToUpper().EndsWith("M"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024 * 1024;
}
else if (v.ToUpper().EndsWith("MB"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024 * 1024;
}
else if (v.ToUpper().EndsWith("G"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024 * 1024 * 1024;
}
else if (v.ToUpper().EndsWith("GB"))
{
sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024 * 1024 * 1024;
}
else
{
sz = Int64.Parse(tokens[i + 2]);
}
current = new SizeCriterion
{
Size = sz,
Operator = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1])
};
i += 2;
stateStack.Push(ParseState.CriterionDone);
break;
case "filename":
case "name":
{
if (tokens.Length <= i + 2)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
ComparisonOperator c =
(ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]);
if (c != ComparisonOperator.NotEqualTo && c != ComparisonOperator.EqualTo)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
string m = tokens[i + 2];
// handle single-quoted filespecs (used to include spaces in filename patterns)
if (m.StartsWith("'"))
{
int ix = i;
if (!m.EndsWith("'"))
{
do
{
i++;
if (tokens.Length <= i + 2)
{
throw new ArgumentException(String.Join(" ", tokens, ix, tokens.Length - ix));
}
m += " " + tokens[i + 2];
} while (!tokens[i + 2].EndsWith("'"));
}
// trim off leading and trailing single quotes
m = m.Substring(1, m.Length - 2);
}
current = new NameCriterion
{
MatchingFileSpec = m,
Operator = c
};
i += 2;
stateStack.Push(ParseState.CriterionDone);
}
break;
case "attributes":
{
if (tokens.Length <= i + 2)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
ComparisonOperator c =
(ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]);
if (c != ComparisonOperator.NotEqualTo && c != ComparisonOperator.EqualTo)
{
throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i));
}
current = new AttributesCriterion
{
AttributeString = tokens[i + 2],
Operator = c
};
i += 2;
stateStack.Push(ParseState.CriterionDone);
}
break;
case "":
// NOP
stateStack.Push(ParseState.Whitespace);
break;
default:
throw new ArgumentException("'" + tokens[i] + "'");
}
state = stateStack.Peek();
if (state == ParseState.CriterionDone)
{
stateStack.Pop();
if (stateStack.Peek() == ParseState.ConjunctionPending)
{
while (stateStack.Peek() == ParseState.ConjunctionPending)
{
var cc = critStack.Pop() as CompoundCriterion;
cc.Right = current;
current = cc; // mark the parent as current (walk up the tree)
stateStack.Pop(); // the conjunction is no longer pending
state = stateStack.Pop();
if (state != ParseState.CriterionDone)
{
throw new ArgumentException("??");
}
}
}
else
{
stateStack.Push(ParseState.CriterionDone); // not sure?
}
}
if (state == ParseState.Whitespace)
{
stateStack.Pop();
}
}
return(current);
}
