require "rake"
require "pathname"

module DtcRake
  def configure(&block)
    config = Config.instance
    yield config
    config.validate!
  end
  module_function :configure

  class Config
    include Singleton

    def initialize
      self.root_dir   = Dir.pwd
      self.output_dir = "target"
      self.colorize   = true
      self.upload_readme = false
      self.appbox_meta_artifact_code = "UU.OS/RUNTIME/APP_BOX"
      self.upload_uucloud_descriptor = false
      self.version_files = []
      guess_vendor_and_app
    end

    # Code of application. Guessed from root_dir name if not set.
    attr_accessor :app

    # Code of appbox artifact. Guessed from product_code and appbox_version
    # if not set.
    attr_accessor :appbox_artifact_code

    # Code of appbox location (folder or organization unit). Required.
    attr_accessor :appbox_location_code

    # Code of appbox meta artifact. Default value: UU.OS/RUNTIME/APP_BOX.
    attr_accessor :appbox_meta_artifact_code

    # Code of territory where the appbox artifact is / should be. Required.
    attr_accessor :appbox_territory_code

    # Path to uarchive with contents of appbox artifact. Default value: nil.
    # If not set, appbox is created with empty content.
    # Relative path is relative to root_dir.
    attr_accessor :appbox_uarchive

    # Appbox version. Read from VERSION file located in the same directory
    # as Rakefile if not set.
    attr_accessor :appbox_version

    # Print messages in colors. Default value: true.
    attr_accessor :colorize

    # Name of folder with build products. Default value: target.
    # Relative path is relative to root_dir.
    attr_accessor :output_dir

    # Code of product the appbox belongs to. Required.
    attr_accessor :product_code

    # Name of product the appbox belongs to. Required.
    attr_accessor :product_name

    # Appbox project root folder. Default value: current working directory.
    attr_accessor :root_dir

    # Upload README.md or README.txt to appbox artifact. Default value: false.
    attr_accessor :upload_readme

    # Upload uuApp deployment descriptor to appbox artifact. Default value: false.
    attr_accessor :upload_uucloud_descriptor

    # Path to uuApp deployment descriptor. Default value: uucloud_descriptor.json.
    attr_accessor :uucloud_descriptor_path

    # Code of vendor. Guessed from root_dir name if not set.
    attr_accessor :vendor

    # List of files (or glob patterns) determining which files get updated by
    # version:* tasks. Default: none.
    attr_accessor :version_files

    def validate!
      %w(appbox_location_code appbox_territory_code product_code product_name).each do |param|
        if instance_variable_get("@#{param}").nil?
          _error "Required parameter #{param} is not set. Set it within DtcRake.configure in your Rakefile."
        end
      end
    end

    def app=(name)
      @app = name.downcase unless name.nil?
    end

    def appbox_artifact_code
      return @appbox_artifact_code if @appbox_artifact_code

      @appbox_artifact_code = ENV["DTC_RAKE_APPBOX_ARTIFACT_CODE"]

      if @appbox_artifact_code.nil?
        default_code = "#{product_code}/APPBOX-#{appbox_version}"
        @appbox_artifact_code = default_code
      end

      @appbox_artifact_code
    end

    def appbox_artifact_code=(code)
      env = ENV["DTC_RAKE_APPBOX_ARTIFACT_CODE"]
      # environment variable takes precedence
      @appbox_artifact_code = env.nil? ? code : env
      @appbox_artifact_code
    end

    def appbox_location_code
      return @appbox_location_code if @appbox_location_code

      @appbox_location_code = ENV["DTC_RAKE_APPBOX_LOCATION_CODE"]
      @appbox_location_code
    end

    def appbox_location_code=(code)
      env = ENV["DTC_RAKE_APPBOX_LOCATION_CODE"]
      # environment variable takes precedence
      @appbox_location_code = env.nil? ? code : env
      @appbox_location_code
    end

    def appbox_meta_artifact_code
      return @appbox_meta_artifact_code if @appbox_meta_artifact_code

      @appbox_meta_artifact_code = ENV["DTC_RAKE_APPBOX_META_ARTIFACT_CODE"]
      @appbox_meta_artifact_code
    end

    def appbox_meta_artifact_code=(code)
      env = ENV["DTC_RAKE_APPBOX_META_ARTIFACT_CODE"]
      # environment variable takes precedence
      @appbox_meta_artifact_code = env.nil? ? code : env
      @appbox_meta_artifact_code
    end

    def appbox_territory_code
      return @appbox_territory_code if @appbox_territory_code

      @appbox_territory_code = ENV["DTC_RAKE_APPBOX_TERRITORY_CODE"]
      @appbox_territory_code
    end

    def appbox_territory_code=(code)
      env = ENV["DTC_RAKE_APPBOX_TERRITORY_CODE"]
      # environment variable takes precedence
      @appbox_territory_code = env.nil? ? code : env
      @appbox_territory_code
    end

    def appbox_uarchive
      return @appbox_uarchive if @appbox_uarchive

      @appbox_uarchive = ENV["DTC_RAKE_APPBOX_UARCHIVE"]
      @appbox_uarchive
    end

    def appbox_uarchive=(path)
      env = ENV["DTC_RAKE_APPBOX_UARCHIVE"]
      # environment variable takes precedence
      path = env unless env.nil?

      unless path.nil?
        # File.expand_path converts path to absolute and expands "~" to real user home path
        path = File.expand_path(path)

        if Pathname.new(path).relative?
          @appbox_uarchive = File.join(root_dir, path)
        else
          @appbox_uarchive = path
        end
      end
    end

    def appbox_version
      return @appbox_version if @appbox_version

      @appbox_version = ENV["DTC_RAKE_APPBOX_VERSION"]

      if @appbox_version.nil?
        version_file = File.join(root_dir, 'VERSION')
        unless File.file?(version_file)
          _error "Unknown appbox version. Set it in #{version_file} file or DTC_RAKE_APPBOX_VERSION environment variable."
        end
        version = File.binread(version_file).strip
        @appbox_version = version
      end
    end

    def appbox_version=(code)
      env = ENV["DTC_RAKE_APPBOX_VERSION"]
      # environment variable takes precedence
      @appbox_version = env.nil? ? code : env
      @appbox_version
    end

    def colorize
      return @colorize if @colorize

      env = ENV["DTC_RAKE_COLORIZE"]
      unless env.nil?
        @colorize = to_bool(env)
      end
      @colorize
    end

    def colorize=(flag)
      env = ENV["DTC_RAKE_COLORIZE"]
      # environment variable takes precedence
      if env.nil?
        @colorize = flag
      else
        @colorize = to_bool(env)
      end
      @colorize
    end

    def output_dir
      return @output_dir if @output_dir

      @output_dir = ENV["DTC_RAKE_OUTPUT_DIR"]
      @output_dir
    end

    def output_dir=(path)
      env = ENV["DTC_RAKE_OUTPUT_DIR"]
      # environment variable takes precedence
      path = env unless env.nil?

      unless path.nil?
        # File.expand_path converts path to absolute and expands "~" to real user home path
        path = File.expand_path(path)

        if Pathname.new(path).relative?
          @output_dir = File.join(root_dir, path)
        else
          @output_dir = path
        end
      end
    end

    def product_code
      return @product_code if @product_code

      @product_code = ENV["DTC_RAKE_PRODUCT_CODE"]
      @product_code
    end

    def product_code=(code)
      env = ENV["DTC_RAKE_PRODUCT_CODE"]
      # environment variable takes precedence
      @product_code = env.nil? ? code : env
      @product_code
    end

    def product_name
      return @product_name if @product_name

      @product_name = ENV["DTC_RAKE_PRODUCT_NAME"]
      @product_name
    end

    def product_name=(name)
      env = ENV["DTC_RAKE_PRODUCT_NAME"]
      # environment variable takes precedence
      @product_name = env.nil? ? name : env
      @product_name
    end

    def root_dir
      return @root_dir if @root_dir

      @root_dir = ENV["DTC_RAKE_ROOT_DIR"]
      @root_dir = Dir.pwd if @root_dir.nil?

      @root_dir
    end

    def root_dir=(path)
      env = ENV["DTC_RAKE_ROOT_DIR"]
      # environment variable takes precedence
      path = env unless env.nil?

      unless path.nil?
        # File.expand_path converts path to absolute and expands "~" to real user home path
        # If the path is relative, it gets evaluated against to current working directory (Dir.pwd)
        @root_dir = File.expand_path(path)
      end
    end

    def upload_readme
      return @upload_readme if @upload_readme

      @upload_readme = to_bool(ENV["DTC_RAKE_UPLOAD_README"])
      @upload_readme
    end

    def upload_readme=(flag)
      env = ENV["DTC_RAKE_UPLOAD_README"]
      # environment variable takes precedence
      if env.nil?
        @upload_readme = flag
      else
        @upload_readme = to_bool(env)
      end
      @upload_readme
    end

    def upload_uucloud_descriptor
      return @upload_uucloud_descriptor if @upload_uucloud_descriptor

      @upload_uucloud_descriptor = to_bool(ENV["DTC_RAKE_UPLOAD_UUCLOUD_DESCRIPTOR"])
      @upload_uucloud_descriptor
    end

    def upload_uucloud_descriptor=(flag)
      env = ENV["DTC_RAKE_UPLOAD_UUCLOUD_DESCRIPTOR"]
      # environment variable takes precedence
      if env.nil?
        @upload_uucloud_descriptor = flag
      else
        @upload_uucloud_descriptor = to_bool(env)
      end
      @upload_uucloud_descriptor
    end

    def uucloud_descriptor_path
      return @uucloud_descriptor_path if @uucloud_descriptor_path

      env = ENV["DTC_RAKE_UUCLOUD_DESCRIPTOR_PATH"]
      if env.nil?
        default_file_path = File.expand_path(File.join(root_dir, "uucloud_descriptor.json"))

        Dir.chdir(root_dir) do
          unless File.file?(default_file_path)
            _error "uuCloud deployment descriptor not found. Please create file #{default_file_path} or configure its path in Rakefile." \
              " Or you can configure its path in DTC_RAKE_UUCLOUD_DESCRIPTOR_PATH environment variable."
          end
          @uucloud_descriptor_path = default_file_path
        end
      else
        env = File.expand_path(env)
        unless File.file?(env)
          _error "uuCloud deployment descriptor not found. Please create file #{env} or configure its path in" \
            " DTC_RAKE_UUCLOUD_DESCRIPTOR_PATH environment variable."
        end
        @uucloud_descriptor_path = env
      end
    end

    def vendor=(name)
      @vendor = name.downcase unless name.nil?
    end

    def version_files=(list)
      if list.nil?
        @version_files = []
      elsif list.is_a?(Array)
        @version_files = list
      else
        _error "Invalid version_files value - #{list} (#{list})." \
          " Use an array of strings (representing file names or glob patterns)."
      end
    end

    private

    def to_bool(value)
      (value =~ /^true|1|yes$/i) == 0
    end

    def guess_vendor_and_app
      env_vendor = ENV["DTC_RAKE_VENDOR"]
      env_app = ENV["DTC_RAKE_APP"]

      if env_vendor.nil? || env_app.nil?
        base_name = File.basename(root_dir)
        if /([^_]+)_([^-]+)-appbox/ =~ base_name
          @vendor = env_vendor.nil? ? $1 : env_vendor
          @app = env_app.nil? ? $2 : env_app
        else
          _error "Appbox root folder (#{base_name}) does not match naming convention <vendor>_<app>-appbox." \
          " Either change the folder name or configure 'vendor' and 'app' within DtcRake.configure in Rakefile." \
          " Or you can set DTC_RAKE_VENDOR and DTC_RAKE_APP environment variables to specify those."
        end
      else
        @vendor = env_vendor
        @app = env_app
      end
    end

    def _error(msg)
      # this avoids cycle between dtc_rake/config and dtc_rake/ui
      require "dtc_rake/ui"
      self.class.send(:include, DtcRake::UI) unless self.class.include?(DtcRake::UI)
      error(msg)
    end
  end
end