public Xeger(string regex, IRandom random)
{
_Automaton = new RegExp(RemoveStartEndMarkers(Check.NotNull(nameof(regex), regex)), _AllExceptAnyString).ToAutomaton();
_Random = random ?? throw new ArgumentNullException(nameof(random));
}
public static Automaton MakeStringMatcher(string s)
{
var a = new Automaton();
var states = new State[s.Length + 1];
states[0] = a.Initial;
for (var i = 0; i < s.Length; i++)
{
states[i + 1] = new State();
}
var f = states[s.Length];
f.Accept = true;
f.Transitions.Add(new Transition(char.MinValue, char.MaxValue, f));
for (var i = 0; i < s.Length; i++)
{
var done = new HashSet <char?>();
var c = s[i];
states[i].Transitions.Add(new Transition(c, states[i + 1]));
_ = done.Add(c);
for (var j = i; j >= 1; j--)
{
var d = s[j - 1];
if (!done.Contains(d) && s.Substring(0, j - 1).Equals(s.Substring(i - j + 1, i - (i - j + 1))))
{
states[i].Transitions.Add(new Transition(d, states[j]));
_ = done.Add(d);
}
}
var da = new char[done.Count];
var h = 0;
foreach (char w in done)
{
da[h++] = w;
}
Array.Sort(da);
int from = char.MinValue;
var k = 0;
while (from <= char.MaxValue)
{
while (k < da.Length && da[k] == from)
{
k++;
from++;
}
if (from <= char.MaxValue)
{
int to = char.MaxValue;
if (k < da.Length)
{
to = da[k] - 1;
k++;
}
states[i].Transitions.Add(new Transition((char)from, (char)to, states[0]));
from = to + 2;
}
}
}
a.IsDeterministic = true;
return(a);
}
public static Automaton MakeTotalDigits(int i) => Automaton.Minimize(
new RegExp("[ \t\n\r]*[-+]?0*([0-9]{0," + i + "}|((([0-9]\\.*){0," + i + "})&@\\.@)0*)[ \t\n\r]*")
.ToAutomaton());
public static Automaton MakeFractionDigits(int i) => Automaton.Minimize(
new RegExp("[ \t\n\r]*[-+]?[0-9]+(\\.[0-9]{0," + i + "}0*)?[ \t\n\r]*")
.ToAutomaton());
public static Automaton MakeDecimalValue(string value)
{
var minus = false;
var i = 0;
while (i < value.Length)
{
var c = value[i];
if (c == '-')
{
minus = true;
}
if ((c >= '1' && c <= '9') || c == '.')
{
break;
}
i++;
}
var sb1 = new StringBuilder();
var sb2 = new StringBuilder();
var p = value.IndexOf('.', i);
if (p == -1)
{
_ = sb1.Append(value, i, value.Length - i);
}
else
{
_ = sb1.Append(value, i, p - i);
i = value.Length - 1;
while (i > p)
{
var c = value[i];
if (c >= '1' && c <= '9')
{
break;
}
i--;
}
_ = sb2.Append(value, p + 1, i + 1 - (p + 1));
}
if (sb1.Length == 0)
{
_ = sb1.Append("0");
}
var s = minus ? Automaton.MakeChar('-') : Automaton.MakeChar('+').Optional();
var d = sb2.Length == 0
? Automaton.MakeChar('.').Concatenate(Automaton.MakeChar('0').Repeat(1)).Optional()
: Automaton.MakeChar('.')
.Concatenate(Automaton.MakeString(sb2.ToString()))
.Concatenate(Automaton.MakeChar('0')
.Repeat());
return(Automaton.Minimize(WhitespaceAutomaton
.Concatenate(s.Concatenate(Automaton.MakeChar('0').Repeat()).Concatenate(Automaton.MakeString(sb1.ToString())).Concatenate(d))
.Concatenate(WhitespaceAutomaton)));
}
public Automaton Intersection(Automaton a) => BasicOperations.Intersection(this, a);
public Automaton Concatenate(Automaton a) => BasicOperations.Concatenate(this, a);
public static Automaton Minimize(Automaton a)
{
a.Minimize();
return(a);
}