require 'puppet/parser/ast/branch'

class Puppet::Parser::AST
    # The inline conditional operator.  Unlike CaseStatement, which executes
    # code, we just return a value.
    class Selector < AST::Branch
        attr_accessor :param, :values

        def each
            [@param,@values].each { |child| yield child }
        end

        # Find the value that corresponds with the test.
        def evaluate(scope)
            level = scope.ephemeral_level
            # Get our parameter.
            paramvalue = @param.safeevaluate(scope)

            default = nil

            @values = [@values] unless @values.instance_of? AST::ASTArray or @values.instance_of? Array

            # Then look for a match in the options.
            @values.each do |obj|
                # short circuit asap if we have a match
                return obj.value.safeevaluate(scope) if obj.param.evaluate_match(paramvalue, scope)

                # Store the default, in case it's necessary.
                default = obj if obj.param.is_a?(Default)
            end

            # Unless we found something, look for the default.
            return default.value.safeevaluate(scope) if default

            self.fail Puppet::ParseError, "No matching value for selector param '#{paramvalue}'"
        ensure
            scope.unset_ephemeral_var(level)
        end

        def to_s
            param.to_s + " ? { " + values.collect { |v| v.to_s }.join(', ') + " }"
        end
    end
end