void Apply(Substitution sub, RbnfContext context)
{
var number = context.Number;
context.Text.Append(sub.Text);
switch (sub.Token)
{
// Divide the number by the rule's divisor and format the remainder.
case "→→":
context.Number = Decimal.Remainder(number, Divisor());
context.Ruleset.ApplyRules(context);
break;
// Divide the number by the rule's divisor and format the quotient.
case "←←":
context.Number = Math.Floor(number / Divisor());
context.Ruleset.ApplyRules(context);
break;
case "=":
// Fallback number formating?
if (sub.Descriptor.StartsWith("#") || sub.Descriptor.StartsWith("0"))
{
var formatter = NumberFormatter.Create(context.Locale);
context.Text.Append(formatter.Format(context.Number));
}
// Else goto the ruleset.
else
{
var ruleset = context.RulesetGroup.Rulesets[sub.Descriptor];
ruleset.ApplyRules(context);
}
break;
// Divide the number by the rule's divisor and format the remainder
// with the specified ruleset.
case "→":
context.Number = Decimal.Remainder(number, Divisor());
context.RulesetGroup
.Rulesets[sub.Descriptor]
.ApplyRules(context);
break;
// Divide the number by the rule's divisor and format the quotient
// with the specified ruleset.
case "←":
context.Number = Math.Floor(number / Divisor());
context.RulesetGroup
.Rulesets[sub.Descriptor]
.ApplyRules(context);
break;
case "":
break;
default:
throw new NotSupportedException($"Substitution token '{sub.Token}' is not allowed.");
}
if (sub.Optionals != null && (number % Divisor()) != 0)
{
foreach (var optional in sub.Optionals)
{
Apply(optional, context);
}
}
context.Number = number;
}