# frozen-string-literal: true
#
# Copyright (C) 2019 Thomas Baron
#
# This file is part of term_utils.
#
# term_utils is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 3 of the License.
#
# term_utils is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with term_utils.  If not, see <https://www.gnu.org/licenses/>.
module TermUtils
  module AP
    # Represents the argument list syntax. It holds a list of parameters and
    # levels.
    class Syntax
      # @return [Array<TermUtils::AP::Element>]
      attr_accessor :elements
      # Constructs a new Syntax.
      def initialize
        @elements = []
      end
      # For dup method.
      def initialize_dup(other)
        if other.elements
          @elements = []
          other.elements.each do |e|
            @elements << e.dup
          end
        end
        super
      end
      # Finalizes this one. Internal use.
      # @return [nil]
      def finalize!(opts = {})
        opts[:anonymous] = 0 unless opts.has_key? :anonymous
        @elements.each { |e| e.finalize!(opts) }
      end
      # Creates and adds a new Parameter.
      # @param opts [Hash]
      # @option opts [Symbol] :id
      # @option opts [Integer] :min_occurs Default value is `0`.
      # @option opts [Integer] :max_occurs Default value is `1`.
      # @return [TermUtils::AP::Parameter]
      def define_parameter(opts = {}, &block)
        new_parameter = TermUtils::AP::Parameter.new(opts)
        @elements << new_parameter
        block.call(new_parameter) if block
        new_parameter
      end
      # Creates and adds a new Level.
      # @param opts [Hash]
      # @option opts [Symbol] :id
      # @option opts [Integer] :min_occurs Default value is `0`.
      # @option opts [Integer] :max_occurs Default value is `1`.
      # @return [TermUtils::AP::Level]
      def define_level(opts = {}, &block)
        new_level = TermUtils::AP::Level.new(opts)
        @elements << new_level
        block.call(new_level) if block
        new_level
      end
      # Fetches all direct flagged parameters and levels.
      # @return [Array]
      # @see TermUtils::AP::Syntax#fetch_flagged_elements
      # @see TermUtils::AP::Syntax#fetch_unflagged_parameters
      def fetch_elements
        flagged_elems = {}
        unflagged_params = []
        @elements.each do |e|
          if e.flags.empty?
            # Parameter
            unflagged_params << e
          else
            # Parameter or Level
            e.flags.each do |f|
              flagged_elems[f.to_s] = e
            end
          end
        end
        [flagged_elems, unflagged_params]
      end
      # Fetches all direct flagged parameters and levels.
      # @return [Hash<String, TermUtils::AP::Element>]
      def fetch_flagged_elements
        elems = {}
        @elements.each do |e|
          e.flags.each do |f|
            elems[f.to_s] = e
          end
        end
        elems
      end
      # Fetches all direct unflagged.
      # @return [Array<TermUtils::AP::Parameter>]
      def fetch_unflagged_parameters
        params = []
        @elements.each do |e|
          next unless e.is_a? TermUtils::AP::Parameter
          params << e if e.flags.empty?
        end
        params
      end
    end
  end
end