require "enabler/version"
require "enabler/storage/redis"
require "enabler/errors/rule_already_defined_error"
require "enabler/rule"

module Enabler

	def self.store=(val)
		@@store = val
	end

	def self.store
		@@store
	end

	def self.enabled?(feature, object)
		enabled_via_rule?(feature, object) || 
			enabled_via_storage?(feature, object)
	end

	def self.enabled_via_storage?(feature, object)
		store.enabled?(feature, object)
	end

	def self.enabled_via_rule?(feature, object)
		sym = feature.to_sym
		r = self.rule(sym)
		return false unless r
		r.enabled?(object)
	end

	def self.enable!(feature, object)
		store.add!(feature, object)
	end

	def self.disable!(feature, object)
		store.remove!(feature, object)
	end

	def self.rules
		@@rules ||= [] 
	end

	def self.rule(feature)
		self.rules.select { |item| item.feature == feature.to_sym }.first
	end

	def self.define_rule!(feature, &block)
		sym = feature.to_sym
		raise Errors::RuleAlreadyDefinedError if self.rule(sym)
		self.rules << Rule.new(sym, block)
	end

end