require 'xcodeproj'

module Pod

  # The Pods project.
  #
  # Model class which provides helpers for working with the Pods project
  # through the installation process.
  #
  class Project < Xcodeproj::Project

    # @param  [Pathname, String] path @see path
    # @param  [Bool] skip_initialization
    #         Wether the project should be initialized from scratch.
    #
    def initialize(path, skip_initialization = false)
      super(path, skip_initialization)
      @support_files_group = new_group('Targets Support Files')
      @refs_by_absolute_path = {}
      @pods = new_group('Pods')
      @development_pods = new_group('Development Pods')
    end

    # @return [PBXGroup] The group for the support files of the aggregate
    #         targets.
    #
    attr_reader :support_files_group

    # @return [PBXGroup] The group for the Pods.
    #
    attr_reader :pods

    # @return [PBXGroup] The group for Development Pods.
    #
    attr_reader :development_pods


    public

    # @!group Pod Groups
    #-------------------------------------------------------------------------#

    # Creates a new group for the Pod with the given name and configures its
    # path.
    #
    # @param  [String] pod_name
    #         The name of the Pod.
    #
    # @param  [#to_s] path
    #         The path to the root of the Pod.
    #
    # @param  [Bool] development
    #         Wether the group should be added to the Development Pods group.
    #
    # @param  [Bool] absolute
    #         Wether the path of the group should be set as absolute.
    #
    # @return [PBXGroup] The new group.
    #
    def add_pod_group(pod_name, path, development = false, absolute = false)
      raise "[BUG]" if pod_group(pod_name)

      parent_group = development ? development_pods : pods
      source_tree = absolute ? :absolute : :group
      group = parent_group.new_group(pod_name, path, source_tree)
      group
    end

    # @return [Array<PBXGroup>] Returns all the group of the Pods.
    #
    def pod_groups
      pods.children.objects + development_pods.children.objects
    end

    # Returns the group for the Pod with the given name.
    #
    # @param  [String] pod_name
    #         The name of the Pod.
    #
    # @return [PBXGroup] The group.
    #
    def pod_group(pod_name)
      pod_groups.find { |group| group.name == pod_name }
    end

    # @return [Hash] The names of the specification subgroups by key.
    #
    SPEC_SUBGROUPS = {
      :resources  => 'Resources',
      :frameworks => 'Frameworks',
    }

    # Returns the group for the specification with the give name creating it if
    # needed.
    #
    # @param [String] spec_name
    #                 The full name of the specification.
    #
    # @return [PBXGroup] The group.
    #
    def group_for_spec(spec_name, subgroup_key = nil)
      pod_name = Specification.root_name(spec_name)
      group = pod_group(pod_name)
      raise "[Bug] Unable to locate group for Pod named `#{pod_name}`" unless group
      if spec_name != pod_name
        subspecs_names = spec_name.gsub(pod_name + '/', '').split('/')
        subspecs_names.each do |name|
          group = group[name] || group.new_group(name)
        end
      end

      if subgroup_key
        subgroup_name = SPEC_SUBGROUPS[subgroup_key]
        raise ArgumentError, "Unrecognized subgroup key `#{subgroup_key}`" unless subgroup_name
        group = group[subgroup_name] || group.new_group(subgroup_name)
      end

      group
    end

    # Returns the support files group for the Pod with the given name.
    #
    # @param  [String] pod_name
    #         The name of the Pod.
    #
    # @return [PBXGroup] The group.
    #
    def pod_support_files_group(pod_name)
      group = pod_group(pod_name)
      support_files_group = group['Support Files']
      unless support_files_group
        support_files_group = group.new_group('Support Files')
        support_files_group.source_tree = 'SOURCE_ROOT'
      end
      support_files_group
    end

    public

    # @!group File references
    #-------------------------------------------------------------------------#

    # Adds a file reference to given path as a child of the given group.
    #
    # @param  [Array<Pathname,String>] absolute_path
    #         The path of the file.
    #
    # @param  [PBXGroup] group
    #         The group for the new file reference.
    #
    # @return [PBXFileReference] The new file reference.
    #
    def add_file_reference(absolute_path, group)
      unless Pathname.new(absolute_path).absolute?
        raise ArgumentError, "Paths must be absolute #{absolute_path}"
      end

      if ref = reference_for_path(absolute_path)
        ref
      else
        ref = group.new_file(absolute_path)
        @refs_by_absolute_path[absolute_path.to_s] = ref
      end
    end

    # Returns the file reference for the given absolute path.
    #
    # @param  [#to_s] absolute_path
    #         The absolute path of the file whose reference is needed.
    #
    # @return [PBXFileReference] The file reference.
    # @return [Nil] If no file reference could be found.
    #
    def reference_for_path(absolute_path)
      unless Pathname.new(absolute_path).absolute?
        raise ArgumentError, "Paths must be absolute #{absolute_path}"
      end

      refs_by_absolute_path[absolute_path.to_s]
    end

    # Adds a file reference to the Podfile.
    #
    # @param  [#to_s] podfile_path
    #         The path of the Podfile.
    #
    # @return [PBXFileReference] The new file reference.
    #
    def add_podfile(podfile_path)
      podfile_ref = new_file(podfile_path, :project)
      podfile_ref.xc_language_specification_identifier = 'xcode.lang.ruby'
      podfile_ref.last_known_file_type = 'text'
      podfile_ref
    end

    # Adds a new build configuration to the project and populates its with
    # default settings according to the provided type.
    #
    # @note   This method extends the original Xcodeproj implementation to
    #         include a preprocessor definition named after the build
    #         setting. This is done to support the TargetEnvironmentHeader
    #         specification of Pods available only on certain build
    #         configurations.
    #
    # @param  [String] name
    #         The name of the build configuration.
    #
    # @param  [Symbol] type
    #         The type of the build configuration used to populate the build
    #         settings, must be :debug or :release.
    #
    # @return [XCBuildConfiguration] The new build configuration.
    #
    def add_build_configuration(name, type)
      build_configuration = super
      values = ["#{name.gsub(' ', '_').upcase}=1"]
      settings = build_configuration.build_settings
      definitions = Array(settings['GCC_PREPROCESSOR_DEFINITIONS'])
      values.each do |value|
        unless definitions.include?(value)
          definitions << value
        end
      end
      settings['GCC_PREPROCESSOR_DEFINITIONS'] = definitions
      build_configuration
    end

    private

    # @!group Private helpers
    #-------------------------------------------------------------------------#

    # @return [Hash{String => PBXFileReference}] The file references grouped
    #         by absolute path.
    #
    attr_reader :refs_by_absolute_path

    #-------------------------------------------------------------------------#

  end
end
