require "core/project"
require "java/artifact"
require "java/java"
require "java/compile"
require "tasks/zip"


module Buildr
  module Java

    # This module includes comming packaging classes. Each one is also reflected by
    # a packaging method. Generally, you would want to use the packaging method from
    # the project definition, since it does all the heavy lifting.
    module Packaging

      MANIFEST_HEADER = "Manifest-Version: 1.0\nCreated-By: Buildr\n"

      # Extends the ZipTask to create a JAR file.
      #
      # This task supports two additional attributes: manifest and meta-inf.
      #
      # The manifest attribute specifies how to create the MANIFEST.MF file.
      # * A hash of manifest properties (name/value pairs).
      # * An array of hashes, one for each section of the manifest.
      # * A string providing the name of an existing manifest file.
      # * A file task can be used the same way.
      # * Proc or method called to return the contents of the manifest file.
      # * False to not generate a manifest file.
      #
      # The meta-inf attribute lists one or more files that should be copied into
      # the META-INF directory.
      #
      # For example:
      #   package(:jar).using(:manifest=>"src/MANIFEST.MF")
      #   package(:jar).meta_inf << file("README")
      class JarTask < ZipTask

        # Specifies how to create the manifest file.
        attr_accessor :manifest

        # Specifies files to include in the META-INF directory.
        attr_accessor :meta_inf

        def initialize(*args) #:nodoc:
          super
          @manifest = true
          @meta_inf = []
        end

        def []=(key, value) #:nodoc:
          if key.to_sym == :manifest
            self.manifest = value
          elsif key.to_sym == :meta_inf
            self.meta_inf = [value].flatten
          else
            super key, value
          end
          value
        end

        def prerequisites() #:nodoc:
          super + [ String === manifest ? file(manifest) : nil ].compact +
            [meta_inf].flatten.map { |file| String === file ? file(file) : file }
        end

      protected

        def create(zip) #:nodoc:
          [meta_inf].flatten.map(&:to_s).uniq.each { |file| zip.add "META-INF/#{File.basename(file)}", file }
          unless manifest == false
            zip.file.open("META-INF/MANIFEST.MF", "w") do |output|
              output << MANIFEST_HEADER
              if manifest
                case manifest
                when Hash
                  output << manifest.map { |pair| pair.map(&:to_s).join(": ") }.sort.join("\n") << "\n"
                when Array
                  output << manifest.reject { |section| section.empty? }.map { |section|
                      section.map { |pair| pair.join(": ") }.sort.join("\n").concat("\n")
                    }.join("\n") << "\n"
                when Proc, Method
                  output << manifest.call 
                when String, Task
                  output << File.read(manifest.to_s)
                end
              end
            end
          end
          super zip
        end

      end

      # Extends the JarTask to create a WAR file.
      #
      # Supports all the same options as JarTask, in additon to these two options:
      # * :libs -- An array of files, tasks, artifact specifications, etc that will be added
      #   to the WEB-INF/lib directory.
      # * :classes -- A directory containing class files for inclusion in the WEB-INF/classes
      #   directory.
      #
      # For example:
      #   package(:war).using(:libs=>"log4j:log4j:jar:1.1")
      class WarTask < JarTask

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

      end

    end
  end


  class Project

    # Options accepted by #package method for all package types.
    PACKAGE_OPTIONS = [:group, :id, :version, :type, :classifier]

    # The project's identifier. Same as the project name, with colons replaced by dashes.
    # The ID for project foo:bar is foo-bar.
    attr_reader :id
    def id()
      name.gsub(":", "-")
    end

    # Group used for packaging. Inherited from parent project. Defaults to the top-level project name.
    attr_accessor :group
    inherited_attr(:group) { |project| project.name }

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

    # Manifest used for packaging. Inherited from parent project. The default value is a hash that includes
    # the Build-By, Build-Jdk, Implementation-Title and Implementation-Version values.
    # The later are taken from the project's comment (or name) and version number.
    attr_accessor :manifest
    inherited_attr :manifest do |project|
      manifest = { "Build-By"=>ENV['USER'], "Build-Jdk"=>Java.version }
      manifest["Implementation-Title"] = self.comment || self.name
      manifest["Implementation-Version"] = project.version if project.version
      manifest
    end

    # Files to always include in the package META-INF directory. The default value include
    # the LICENSE file if one exists in the project's base directory.
    attr_accessor :meta_inf
    inherited_attr(:meta_inf) do |project|
      license = project.file("LICENSE")
      File.exist?(license.to_s) ? [license] : []
    end

    # :call-seq:
    #   package(type, options?) => task
    #
    # Defines and returns a package created by this project.
    #
    # The first argument declares the package type. For example, :jar to create a JAR file.
    # The second argument provides additional options used when defining the package.
    #
    # The following options are supported by all package types:
    # * :id -- The artifact identifier. By default, uses the project's #id property.
    # * :group -- The group identifier. By default, uses the project's #group property.
    # * :version -- The version number. By default, uses the project's #version property.
    # * :classifier -- Artifact classifier. By default, the artifact has no classifier.
    #
    # The JAR packager adds the following options:
    # * :manifest -- Specifies how to create the MANIFEST.MF. By default, uses the project's
    #   #manifest property.
    # * :meta_inf -- Specifies files to be included in the META-INF directory. By default,
    #   uses the project's #meta-inf property.
    # * :include -- List of files and directories to include in the JAR. By default,
    #   includes the contents of the target/classes directory.
    #
    # The WAR packager adds the following options:
    # * :manifest -- See JAR.
    # * :meta_inf -- See JAR.
    # * :classes -- Directories of class files to include in WEB-INF/classes. By default,
    #   includes the contents of the target/classes directory.
    # * :libs -- Artifacts and files to include in WEB-INF/libs. By default, includes the
    #   compile classpath.
    # * :include -- List of files and directories to include in the JAR. By default,
    #   includes the contents of the src/main/webapp directory.
    #
    # The ZIP packager adds the following options:
    # * :include -- List of file and directories to include in the ZIP.
    #
    # In addition, you can always enhance the package task directly, e.g. by calling the
    # ZipTask#include and ZipTask#with methods.
    #
    # For example:
    #   define "project" do
    #     define "beans" do
    #       package :jar
    #     end
    #     define "webapp" do
    #       compile.with project("beans")
    #       package :war
    #     end
    #     package :zip, :classifier=>"sources", :include=>"."
    #  end
    #
    # The first time you call package, it defines the new task. Afterwards, it only uses some of the
    # options (file_name, id, etc) to find an existing package task and return it.
    #
    # For example:
    #   # Create a new package that includes an existing package.
    #   package(:war).include project("foo:bar").package(:jar)
    #
    # A package is also an artifact. The following tasks operate on packages created by the project:
    #   rake deploy     # Deploy packages created by the project
    #   rake install    # Install packages created by the project
    #   rake package    # Create packages
    #   rake uninstall  # Remove previously installed packages
    #
    # If you want to add additional packaging types, implement a method with the name package_as_[type]
    # that accepts two arguments, the file name and a hash of options. The method must yield to the
    # block with the package only when first called to define the package, and must return the package
    # from each call.
    def package(type = :jar, options = nil)
      options = options.nil? ? {} : options.dup
      options[:id] ||= self.id
      options[:group] ||= self.group
      options[:version] ||= self.version
      options[:type] = type
      file_name = path_to(:target, Artifact.hash_to_file_name(options))

      packager = method("package_as_#{type}") rescue
        fail("Don't know how to create a package of type #{type}")
      packager.call(file_name, options) do |package|
        # Make it an artifact using the specifications, and tell it how to create a POM.
        package.extend ActsAsArtifact
        package.send :apply_spec, Hash[*Artifact::ARTIFACT_ATTRIBUTES.map { |k| [ k,options[k]] }.flatten]
        # Another task to create the POM file.
        pom_spec = package.to_spec_hash.merge(:type=>:pom)
        pom = file(Buildr.repositories.locate(pom_spec))
        pom.extend ActsAsArtifact
        pom.send :apply_spec, pom_spec
        pom.enhance do
          mkpath File.dirname(pom.name), :verbose=>false
          File.open(pom.name, "w") do |file|
            xml = Builder::XmlMarkup.new(:target=>file, :indent=>2)
            xml.instruct!
            xml.project do
              xml.modelVersion  "4.0.0"
              xml.groupId       pom.group
              xml.artifactId    pom.id
              xml.version       pom.version
              xml.classifier    pom.classifier if pom.classifier
            end
          end
        end

        # Make sure the package task creates it, and it invokes the build task first.
        task "package"=>package
        package.enhance [task("build")]

        # Install the artifact along with its POM. Since the artifact (package task) is created
        # in the target directory, we need to copy it into the local repository. However, the
        # POM artifact (created by calling artifact on its spec) is already mapped to its right
        # place in the local repository, so we only need to invoke it.
        installed = file(Buildr.repositories.locate(package)=>package) { |task|
          verbose(Rake.application.options.trace || false) do
            mkpath File.dirname(task.name), :verbose=>false
            cp package.name, task.name
          end
          puts "Installed #{task.name}" if verbose
        }
        task "install"=>[installed, pom]
        task "uninstall" do |task|
          verbose(Rake.application.options.trace || false) do
            [ installed, pom ].map(&:to_s).each { |file| rm file if File.exist?(file) } 
          end
        end
        task("deploy") { deploy(package, pom) }

        # Add the package to the list of packages created by this project, and
        # register it as an artifact. The later is required so if we look up the spec
        # we find the package in the project's target directory, instead of finding it
        # in the local repository and attempting to install it.
        packages << package
        Artifact.register package, pom
      end
    end

    # :call-seq:
    #   packages() => tasks
    #
    # Returns all packages created by this project. A project may create any number of packages.
    #
    # This method is used whenever you pass a project to Buildr#artifact or any other method
    # that accepts artifact specifications and projects. You can use it to list all packages
    # created by the project. If you want to return a specific package, it is often more
    # convenient to call #package with the type.
    def packages()
      @packages ||= []
    end

  protected

    def package_as_jar(file_name, options) #:nodoc:
      unless Rake::Task.task_defined?(file_name)
        rake_check_options options, *PACKAGE_OPTIONS + [:manifest, :meta_inf, :include]
        Java::Packaging::JarTask.define_task(file_name).tap do |jar|
          jar.manifest = options.has_key?(:manifest) ? options[:manifest] : manifest
          jar.meta_inf = options[:meta_inf] || meta_inf
          if options[:include]
            jar.include options[:include]
          else
            # Can only decide on this once we're done configuring the compile task.
            enhance { jar.include compile.target, :as=>"." }
          end
          yield jar
        end
      else
        rake_check_options options, *PACKAGE_OPTIONS
      end
      file(file_name)
    end

    def package_as_war(file_name, options) #:nodoc:
      unless Rake::Task.task_defined?(file_name)
        rake_check_options options, *PACKAGE_OPTIONS + [:manifest, :meta_inf, :classes, :libs, :include]
        Java::Packaging::WarTask.define_task(file_name).tap do |war|
          war.manifest = options.has_key?(:manifest) ? options[:manifest] : manifest
          war.meta_inf = options[:meta_inf] || meta_inf
          # Add libraries in WEB-INF lib, and classes in WEB-INF classes
          if options[:classes]
            war.with :classes=>options[:classes]
          else
            # Can only decide on this once we're done configuring the compile task.
            enhance { war.with :classes=>compile.target unless compile.sources.empty? }
          end
          if options[:libs]
            war.with :libs=>options[:libs].collect
          else
            # Can only decide on this once we're done configuring the compile task.
            enhance { war.with :libs=>compile.classpath }
          end
          # Add included files, or the webapp directory.
          if options[:include]
            war.include options[:include]
          elsif File.exist?(path_to("src/main/webapp"))
            war.include path_to("src/main/webapp"), :as=>"."
          end
          yield war
        end
      else
        rake_check_options options, *PACKAGE_OPTIONS
      end
      file(file_name)
    end

    def package_as_zip(file_name, options) #:nodoc:
      unless Rake::Task.task_defined?(file_name)
        rake_check_options options, *PACKAGE_OPTIONS + [:include]
        ZipTask.define_task(file_name).tap do |zip|
          if options[:include]
            zip.include options[:include]
          end
          yield zip
        end
      else
        rake_check_options options, *PACKAGE_OPTIONS
      end
      file(file_name)
    end

  end

end