#-- encoding: UTF-8
#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2015 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) 2006-2013 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.
#++

class CustomValue < ActiveRecord::Base
  FORMAT_STRATEGIES = {
    'string' => CustomValue::StringStrategy,
    'text' => CustomValue::StringStrategy,
    'int' => CustomValue::IntStrategy,
    'float' => CustomValue::FloatStrategy,
    'date' => CustomValue::DateStrategy,
    'bool' => CustomValue::BoolStrategy,
    'user' => CustomValue::UserStrategy,
    'version' => CustomValue::VersionStrategy,
    'list' => CustomValue::ListStrategy
  }

  belongs_to :custom_field
  belongs_to :customized, polymorphic: true

  before_save :to_db_value

  validate :validate_presence_of_required_value
  validate :validate_format_of_value
  validate :validate_type_of_value
  validate :validate_length_of_value

  after_initialize :set_default_value

  def set_default_value
    if new_record? && custom_field && (customized_type.blank? || (customized && customized.new_record?))
      self.value ||= custom_field.default_value
    end
  end

  # returns the value of this custom value, but converts it according to the field_format
  # of the custom field beforehand
  def typed_value
    strategy.typed_value
  end

  def editable?
    custom_field.editable?
  end

  def visible?
    custom_field.visible?
  end

  def required?
    custom_field.is_required?
  end

  def to_s
    value.to_s
  end

  protected

  def to_db_value
    self.value = strategy.db_value
  end

  def validate_presence_of_required_value
    errors.add(:value, :blank) if custom_field.is_required? && !strategy.value_present?
  end

  def validate_format_of_value
    if value.present?
      errors.add(:value, :invalid) unless custom_field.regexp.blank? or value =~ Regexp.new(custom_field.regexp)
    end
  end

  def validate_type_of_value
    if value.present?
      validation_error = strategy.validate_type_of_value
      if validation_error
        errors.add(:value, validation_error)
      end
    end
  end

  def validate_length_of_value
    if value.present? && custom_field.min_length.present? && custom_field.max_length.present?
      errors.add(:value, :too_short, count: custom_field.min_length) if custom_field.min_length > 0 and value.length < custom_field.min_length
      errors.add(:value, :too_long, count: custom_field.max_length) if custom_field.max_length > 0 and value.length > custom_field.max_length
    end
  end

  private

  def strategy
    @strategy ||= FORMAT_STRATEGIES[custom_field.field_format].new(self)
  end
end