#
#  Copyright (C) 2014-2018  Enrico Rivarola
#
#  This file is part of DcmDict gem (dcm_dict).
#
#  DcmDict 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, either version 3 of the License, or
#  (at your option) any later version.
#
#  DcmDict 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 DcmDict.  If not, see <http://www.gnu.org/licenses/>.
#
#  This software has neither been tested nor approved for clinical use
#  or for incorporation in a medical device.
#  It is the redistributor's or user's responsibility to comply with any
#  applicable local, state, national or international regulations.
#
require_relative 'base_dictionary'

module DcmDict
  module Dictionary
    DataElementIndexKey = [:tag_ps, :tag_name, :tag_key, :tag_str,
                           :tag_sym, :tag_ndm, :tag_ary]

    # Main class to handle data element data as dictionary
    class DataElementDictionary < BaseDictionary
      using DcmDict::Refine::Internal::ArrayRefineInternal
      using DcmDict::Refine::Internal::StringRefineInternal

      def initialize
        super
      end

      private
      def map_source_data
        @standard_dict = {}
        @multi_dict = []
        SourceData::DataElementsData.each do |data|
          record = DataElementRecord.new(data).freeze
          DataElementIndexKey.each { |key| @standard_dict[data[key]] = record }
          @multi_dict << record if record.tag_multiple?
        end
      end

      def freeze_source_data
        @standard_dict.freeze
        @multi_dict.freeze
      end

      def atomic_feature_at(tag, key)
        try_to_find_feature(tag, key)
      rescue Exception => ex
        raise DictionaryError.new("Unable to find feature #{key.inspect} for tag '#{tag}' (#{ex.class}: #{ex.message.inspect})")

      end

      def try_to_find_feature(tag, key)
        atomic_record_at(tag).send(key)
      end

      def atomic_record_at(tag)
        try_to_find(tag)
      rescue Exception => ex
        raise DictionaryError.new("Unable to find reference for tag '#{tag}' as #{tag.class} (#{ex.class}: #{ex.message.inspect})")
      end

      def try_to_find(tag)
        try_to_find_standard_tag(tag) ||
          try_to_find_group_length_tag(tag) ||
          try_to_find_multiple_tag(tag) ||
          try_to_find_private_creator_tag(tag) ||
          try_to_find_unknown_tag(tag)
      end

      def try_to_find_standard_tag(tag)
        @standard_dict[tag]
      end

      def try_to_find_multiple_tag(tag)
        @multi_dict.each do |record|
          mrec = record.extract_multiple_tag_record(tag)
          return mrec if mrec
        end
        nil
      end

      def try_to_find_group_length_tag(tag)
        if (tag.group_length_tag?)
          return DataElementRecord.new(
                   SourceData::DetachedData.make_group_length_data(tag))
        end
      end

      def try_to_find_private_creator_tag(tag)
        if ( tag.private_creator_tag? )
          return DataElementRecord.new(
                   SourceData::DetachedData.make_private_creator_data(tag))
        end
      end

      def try_to_find_unknown_tag(tag)
        DataElementRecord.new(
          SourceData::DetachedData.make_unknown_data(tag))
      end

    end

    TheDataElementDictionary = DataElementDictionary.new.freeze

  end
end