begin
  require 'psych'
rescue ::LoadError
end

require 'yaml'

class Jeweler
  class VersionHelper
    attr_accessor :base_dir
    attr_reader :major, :minor, :patch, :build

    module YamlExtension
      def write
        File.open(yaml_path, 'w+') do |f|
          YAML.dump(to_hash, f)
        end
      end

      def to_hash
        {
          major: major,
          minor: minor,
          patch: patch,
          build: build
        }
      end

      def refresh
        parse_yaml
      end

      def parse_yaml
        yaml = read_yaml
        @major = (yaml['major'] || yaml[:major]).to_i
        @minor = (yaml['minor'] || yaml[:minor]).to_i
        @patch = (yaml['patch'] || yaml[:patch]).to_i
        @build = (yaml['build'] || yaml[:build])
      end

      def read_yaml
        if File.exist?(yaml_path)
          YAML.load_file(yaml_path)
        else
          raise VersionYmlError, "#{yaml_path} does not exist!"
        end
      end

      def path
        yaml_path
      end
    end

    module PlaintextExtension
      def write
        File.open(plaintext_path, 'w') do |file|
          file.write to_s
        end
      end

      def parse_plaintext
        plaintext = read_plaintext.chomp
        # http://rubular.com/regexes/10467 -> 3.5.4.a1
        # http://rubular.com/regexes/10468 -> 3.5.4
        if plaintext =~ /^(\d+)\.(\d+)\.(\d+)(?:\.(.*?))?$/
          @major = $1.to_i
          @minor = $2.to_i
          @patch = $3.to_i
          @build = $4
        end
      end

      def read_plaintext
        File.read(plaintext_path)
      end

      def refresh
        parse_plaintext
      end

      def path
        plaintext_path
      end
    end

    def initialize(base_dir)
      self.base_dir = base_dir

      if File.exist?(yaml_path)
        extend YamlExtension
        parse_yaml
      else
        extend PlaintextExtension
        parse_plaintext if File.exist?(plaintext_path)
      end
    end

    def bump_major
      @major += 1
      @minor = 0
      @patch = 0
      @build = nil
    end

    def bump_minor
      @minor += 1
      @patch = 0
      @build = nil
    end

    def bump_patch
      @patch += 1
      @build = nil
    end

    def update_to(major, minor, patch, build = nil)
      @major = major
      @minor = minor
      @patch = patch
      @build = build
    end

    def to_s
      [major, minor, patch, build].compact.join('.')
    end

    def yaml_path
      path_to_version_file('VERSION.yml')
    end

    def plaintext_path
      path_to_version_file('VERSION')
    end

  private

    def path_to_version_file(filename)
      denormalized_path = File.join(@base_dir, filename)
      absolute_path = File.expand_path(denormalized_path)
      absolute_path.gsub(Dir.getwd + File::SEPARATOR, '')
    end

  end
end