#pragma warning restore 1591
/// <summary>
/// ѕреобразует строку с выражением в набор <see cref="SimpleExpressionItem"/>
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
public SimpleExpressionItem Parse(string expression)
{
SimpleExpressionItem result = new SimpleExpressionItem {
Type = SimpleExpressionItemType.Group, Opener = Openers[0], Closer = Closers[0]
};
InternalParse(expression, result);
return(AccomodateResult(result));
}
public SimpleExpressionItem Append(SimpleExpressionItem item) {
if (0 != Children.Count) {
var last = Children[Children.Count - 1];
last.Next = item;
item.Previous = last;
}
item.Parent = this;
Children.Add(item);
return this;
}
public SimpleExpressionItem Append(SimpleExpressionItem item)
{
if (0 != Children.Count)
{
var last = Children[Children.Count - 1];
last.Next = item;
item.Previous = last;
}
item.Parent = this;
Children.Add(item);
return(this);
}
private static SimpleExpressionItem AccomodateResult(SimpleExpressionItem result)
{
if (result.Children.Count == 0)
{
result = new SimpleExpressionItem {
Value = null
};
}
while (result.Children.Count == 1)
{
result = result.Children[0];
}
return(result);
}
public void InsertAfter(SimpleExpressionItem i)
{
i.Next = this.Next;
if (null != i.Next)
{
i.Next.Previous = i;
}
i.Parent = this.Parent;
if (null != i.Parent)
{
if (null == i.Next)
{
i.Parent.Children.Add(i);
}
else
{
i.Parent.Children.Insert(i.Parent.Children.IndexOf(i.Next), i);
}
}
}
private void InternalParse(string expression, SimpleExpressionItem result)
{
var target = result;
var skip = 0;
char c = '\0';
char next = '\0';
char prefix = '\0';
bool quoted = false;
bool literal = false;
Action newItem = () => {
var newitem = new SimpleExpressionItem {
Prefix = prefix
};
prefix = '\0';
target.Append(newitem);
target = newitem;
};
Func <bool, bool> endItem = (n) => {
bool r = false;
if (n)
{
if (-1 != Array.IndexOf(Suffixes, next))
{
target.Suffix = next;
skip = 1;
}
}
else
{
if (-1 != Array.IndexOf(Suffixes, c))
{
target.Suffix = c;
r = true;
}
}
quoted = false;
literal = false;
target = target.Parent;
return(r);
};
for (var i = 0; i < expression.Length; i++)
{
if (skip > 0)
{
skip--;
continue;
}
next = i == expression.Length - 1 ? '\0' : expression[i + 1];
c = expression[i];
if (quoted) //we are in quoted string
{
if (c == Escape)
{
if (next == target.Quote)
{
target.Value += next;
skip = 1;
continue;
}
}
if (c == target.Quote)
{
endItem(true);
continue;
}
target.Value += c;
continue;
}
if (-1 != Array.IndexOf(Quotes, c))
{
newItem();
target.IsQuoted = true;
target.Quote = c;
quoted = true;
continue;
}
if (!char.IsLetterOrDigit(c) && literal)
{
if (endItem(false))
{
continue;
}
}
if (char.IsLetterOrDigit(c))
{
if (!literal)
{
newItem();
literal = true;
}
target.Value += c;
}
if (-1 != Array.IndexOf(Prefixes, c))
{
prefix = c;
continue;
}
if (char.IsWhiteSpace(c))
{
continue;
}
if (-1 != Array.IndexOf(Operators, c))
{
target.Append(new SimpleExpressionItem {
Type = SimpleExpressionItemType.Operator,
Value = c.ToString(CultureInfo.InvariantCulture)
});
continue;
}
if (-1 != Array.IndexOf(Closers, c))
{
if (target.Opener != '\0')
{
if (c == target.Closer)
{
endItem(false);
continue;
}
}
}
if (-1 != Array.IndexOf(Openers, c))
{
newItem();
target.Type = SimpleExpressionItemType.Group;
target.Opener = c;
var idx = Array.IndexOf(Openers, c);
target.Closer = Closers[idx];
continue;
}
}
}
public void InsertAfter(SimpleExpressionItem i) {
i.Next = this.Next;
if (null != i.Next) {
i.Next.Previous = i;
}
i.Parent = this.Parent;
if (null != i.Parent) {
if (null == i.Next) {
i.Parent.Children.Add(i);
}
else {
i.Parent.Children.Insert(i.Parent.Children.IndexOf(i.Next),i);
}
}
}
