wjessop/fuzzy_version_matcher

require "fuzzy_version_matcher/version"

module FuzzyVersionMatcher
    class Node
        def initialize
            @nodes = {}
            @version = nil
            @segment = nil
        end

        def add_node(version_string, version_segments = nil)
            # If version_segments is nil we are the top node, create a version_segments array
            version_segments ||= string_to_segments(version_string)

            next_segment = version_segments.shift
            if version_segments.size == 0
                # We got to the last remaining version segment, we need to store the whole version string in this node
                @version = version_string
            else
                @nodes[next_segment] = self.class.new unless @nodes.has_key? next_segment
                @nodes[next_segment].add_node(version_string, version_segments)
            end
            @segment = next_segment
        end

        def search(version_string, version_segments = nil)
            # If version_segments is nil we are the top node, create a version_segments array
            version_segments ||= string_to_segments(version_string)

            next_segment = version_segments.shift
            if @nodes.has_key? next_segment
                @nodes[next_segment].search(version_string, version_segments)
            else
                return (!@version.nil? && version_segments.size == 0) ? @version : traverse_high
            end
        end

        protected

        def traverse_high
            if @nodes.size > 0
                return @nodes.sort_by{|seg| seg}.last.last.traverse_high || @version
            else
                return @version
            end
        end

        private

        def string_to_segments(version_string)
            version_string.split(/[^a-zA-Z0-9]/)
        end
    end
end