# Copyright, 2012, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

require 'date'

module Relaxo
	module Model
		module Properties
			# Handle conversions for standard datatypes.
			class Attribute
				@@attributes = {}
				
				def self.for_class(klass, &block)
					@@attributes[klass] = Proc.new(&block)
				end
				
				def self.[](klass, proc = nil)
					self.new(klass, &proc)
				end
				
				def initialize(klass, &serialization)
					@klass = klass
					
					if block_given?
						self.instance_eval(&serialization)
					else
						self.instance_eval(&@@attributes[klass])
					end
				end
			end
			
			class Serialized
				def self.[](klass, proc = nil)
					self.new(klass, &proc)
				end
				
				def initialize(klass, &serialization)
					@klass = klass
				end
				
				def convert_to_primative(value)
					@klass.dump(value)
				end
				
				def convert_from_primative(dataset, value)
					@klass.load(value)
				end
			end
			
			Required = Attribute
			
			class Optional
				def self.[] klass
					self.new(klass)
				end
				
				def initialize(klass)
					@klass = klass
				end
				
				def blank?(value)
					if value.nil?
						return true
					end
					
					if value.respond_to?(:empty?) && value.empty?
						return true
					end
					
					return false
				end
				
				def convert_to_primative(value)
					if blank?(value)
						nil
					else
						@klass.convert_to_primative(value)
					end
				end
				
				def convert_from_primative(dataset, value)
					if blank?(value)
						nil
					else
						@klass.convert_from_primative(dataset, value)
					end
				end
			end
			
			class Boolean
			end
			
			Attribute.for_class(Boolean) do
				def convert_to_primative(value)
					value ? true : false
				end
				
				def convert_from_primative(dataset, value)
					[true, "on", "true"].include?(value)
				end
			end
			
			Attribute.for_class(Integer) do
				def convert_to_primative(value)
					value.to_i
				end
				
				def convert_from_primative(dataset, value)
					value.to_i
				end
			end
			
			Attribute.for_class(Float) do
				def convert_to_primative(value)
					value.to_f
				end
				
				def convert_from_primative(dataset, value)
					value.to_f
				end
			end
			
			Attribute.for_class(Date) do
				def convert_to_primative(value)
					value.iso8601
				end
				
				def convert_from_primative(dataset, value)
					Date.parse(value)
				end
			end
			
			Attribute.for_class(DateTime) do
				def convert_to_primative(value)
					value.iso8601
				end
				
				def convert_from_primative(dataset, value)
					DateTime.parse(value)
				end
			end
			
			Attribute.for_class(String) do
				def convert_to_primative(value)
					value.to_s
				end
				
				def convert_from_primative(dataset, value)
					value.to_s
				end
			end
		end
	end
end