module Buildr
  module Java

    module Packaging

      MANIFEST_HEADER = "Manifest-Version: 1.0\nCreated-By: Ruby Build System"

      class JarTask < ZipTask
        attr_accessor :manifest

        def initialize(*args)
          super
          @manifest = true
        end

        def []=(key, value)
          if key.to_sym == :manifest
            self.manifest = value
          else
            super key, value
          end
          value
        end

      protected

        def create(zip)
          if manifest
            zip.mkdir "META-INF"
            zip.file.open("META-INF/MANIFEST.MF", "w") do |output|
              output.write MANIFEST_HEADER
              case manifest
              when Hash
                output.write manifest.map { |pair| pair.join(": ") }.join("\n")
              when Array
                manifest.each do |section|
                  output.write "\n"
                  output.write section.map { |pair| pair.join(": ") }.join("\n")
                end
              when Proc, Method
                output.write manifest.call 
              when String
                output.write File.read(manifest)
              when true # Default behavior
              end
              output.write "\n"
            end
          end
          super zip
        end

      end

      class WarTask < JarTask

        def []=(key, value)
          case key.to_sym
          when :libs
            self.include value, :path=>"WEB-INF/lib"
          when :classes
            self.include value, :path=>"WEB-INF/classes"
          else
            super key, value
          end
          value
        end

      end

    end
  end


  # Create a JAR from all the pre-requisites.
  #
  # For example:
  #   jar "lib-1.0.jar"=>["target/classes", "MANIFEST,MF"]
  def jar(file)
    Packaging::JarTask.define_task(file)
  end


  # Global task packages all projects.
  desc "Package all projects"
  LocalDirectoryTask.define_task "package"
  desc "Install packages created by this project"
  LocalDirectoryTask.define_task "install"
  desc "Uninstall packages created by this project"
  LocalDirectoryTask.define_task "uninstall"
  desc "Deploy packages created by this project"
  LocalDirectoryTask.define_task "deploy"


  class Project

    # Group used for packaging. Inherited from parent project.
    inherited_attr :group
    # Version used for packaging. Inherited from parent project.
    inherited_attr :version

    inherited_attr :webapp_src_dir do File.join(src_dir, "main", "webapp") end

    def package(*args)
      if Hash === args.last
        options = args.pop.clone
      else
        options = {}
      end
      options[:type] = args.shift if Symbol === args.first
      fail "No packaging type specified" unless options[:type]
      options[:group] ||= self.group
      options[:version] ||= self.version
      options[:id] ||= self.id
      if String === args.first
        file = args.shift
      else
        file = options.delete(:file) || path_to(:target_dir, Artifact.hash_to_file_name(options))
      end
      fail "One argument too many; expecting at most type, file name, and hash of options" unless args.empty?

      packager = method("package_as_#{options[:type]}") rescue
        fail("Do not know how to create a package of type #{options[:type]}")
      package = packager.call(file, options) or fail("Do not know how to create a package of type #{options[:type]}")

      task("package").enhance [package]
      package.enhance [task("build")]

      task "install"=>[
        file_create(File.dirname(repositories.locate(package))) { |task| mkpath task.name, :verbose=>false },
        file(repositories.locate(package)=>package) { |task| cp package.name, task.name },
        package.pom
      ]

      task "uninstall" do |task|
        verbose(Rake.application.options.trace) do
          rm repositories.locate(package)
          rm repositories.locate(package.pom)
        end
      end

      task "deploy"=>deploy(package, package.pom)

      packages << package
      Artifact.register package
      package
    end

    def packages()
      @packages ||= []
    end

  protected

    def package_as_jar(file, options)
      returning(Java::Packaging::JarTask.define_task(file)) do |task|
        package_extend task, options
        task.include path_to(:java_target_dir, "*")
        task.include options[:include] if options[:include]
        task.manifest = options[:manifest] if options[:manifest]
      end
    end

    def package_as_war(file, options)
      # Add anything we find in webapp sources directory.
      returning(Java::Packaging::WarTask.define_task(file)) do |task|
        package_extend task, options
        task.include path_to(:webapp_src_dir, "*")
        task.include options[:include] if options[:include]
        # Add libraries in WEB-INF lib, and classes in WEB-INF classes
        task.with :libs=>options[:libs].collect if options[:libs]
        task.with :classes=>(options[:classes] || path_to(:java_target_dir, "**")) unless options[:classes] == false
      end
    end

    def package_as_zip(file, options)
      returning(ZipTask.define_task(file)) do |task|
        package_extend task, options
        task.include path_to(:java_target_dir, "*")
        task.include options[:include] if options[:include]
      end
    end

    def package_extend(task, spec)
      task.extend ActsAsArtifact
      task.apply_spec spec
      task.pom.enhance do |task|
        mkpath File.dirname(task.name), :verbose=>false
        File.open(task.name, "w") do |file|
          xml = Builder::XmlMarkup.new(:target=>file, :indent=>2)
          xml.instruct!
          xml.project do
            xml.modelVersion  "4.0.0."
            xml.groupId       spec[:group]
            xml.artifactId    spec[:id]
            xml.version       spec[:version]
            xml.classifier    spec[:classifier] if spec[:classifier]
          end
        end
      end
    end

  end


  Project.on_create do |project|
    # Recursive tasks must be defined in before_create.
    desc "Create packages in this project"
    project.recursive_task "package"=>"build"
    desc "Install packages created by this project"
    project.recursive_task "install"=>"package"
    desc "Uninstall packages created by this project"
    project.recursive_task "uninstall"
    desc "Deploy packages created by this project"
    project.recursive_task "deploy"=>"package"
  end

end