#-- encoding: UTF-8
#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2017 the OpenProject Foundation (OPF)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2017 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# This program 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 2
# of the License, or (at your option) any later version.
#
# This program 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 this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See doc/COPYRIGHT.rdoc for more details.
#++

module API
  module V3
    module Utilities
      class DateTimeFormatter
        def self.format_date(date, allow_nil: false)
          return nil if date.nil? && allow_nil
          date.to_date.iso8601
        end

        def self.parse_date(value, property_name, allow_nil: false)
          return nil if value.nil? && allow_nil

          begin
            date_and_time = DateTime.iso8601(value)
          rescue ArgumentError
            raise API::Errors::PropertyFormatError.new(property_name,
                                                       I18n.t('api_v3.errors.expected.date'),
                                                       value)
          end

          date_only = date_and_time.to_date

          # we only want to accept "timeless" dates, e.g. "2015-01-31",
          # but not "2015-01-31T01:02:03".
          # However Date.iso8601 is too generous and would accept that
          unless date_and_time == date_only
            raise API::Errors::PropertyFormatError.new(property_name,
                                                       I18n.t('api_v3.errors.expected.date'),
                                                       value)
          end

          date_only
        end

        def self.format_datetime(datetime, allow_nil: false)
          return nil if datetime.nil? && allow_nil
          datetime.to_datetime.utc.iso8601
        end

        def self.format_duration_from_hours(hours, allow_nil: false)
          return nil if hours.nil? && allow_nil

          Duration.new(hours_and_minutes(hours)).iso8601
        end

        def self.parse_duration_to_hours(duration, property_name, allow_nil: false)
          return nil if duration.nil? && allow_nil

          begin
            iso_duration = ISO8601::Duration.new(duration.to_s)
            iso_duration.to_seconds / 3600.0
          rescue ISO8601::Errors::UnknownPattern
            raise API::Errors::PropertyFormatError.new(property_name,
                                                       I18n.t('api_v3.errors.expected.duration'),
                                                       duration)
          end
        end

        def self.hours_and_minutes(hours)
          hours = hours.to_f
          minutes = (hours - hours.to_i) * 60

          { hours: hours.to_i, minutes: minutes }
        end

        private_class_method :hours_and_minutes
      end
    end
  end
end