case.rb in u-case-2.0.0.pre

- old
+ new
@@ -1,12 +1,93 @@
 # frozen_string_literal: true
 
 require 'micro/attributes'
+# frozen_string_literal: true
 
-require 'micro/case/version'
-require 'micro/case/error'
-require 'micro/case/result'
-require 'micro/case/base'
-require 'micro/case/safe'
-require 'micro/case/strict'
-require 'micro/case/flow/reducer'
-require 'micro/case/flow'
+module Micro
+  class Case
+    require 'micro/case/version'
+    require 'micro/case/result'
+    require 'micro/case/error'
+    require 'micro/case/safe'
+    require 'micro/case/strict'
+    require 'micro/case/flow/reducer'
+    require 'micro/case/flow'
+    require 'micro/case/safe/flow'
+
+    include Micro::Attributes.without(:strict_initialize)
+
+    def self.to_proc
+      Proc.new { |arg| call(arg) }
+    end
+
+    def self.>>(use_case)
+      Flow[self, use_case]
+    end
+
+    def self.&(use_case)
+      Safe::Flow[self, use_case]
+    end
+
+    def self.call(options = {})
+      new(options).call
+    end
+
+    def self.__new__(result, arg)
+      instance = new(arg)
+      instance.__set_result__(result)
+      instance
+    end
+
+    def self.__failure_type(arg, type)
+      return type if type != :error
+
+      case arg
+      when Exception then :exception
+      when Symbol then arg
+      else type
+      end
+    end
+
+    def call!
+      raise NotImplementedError
+    end
+
+    def call
+      __call
+    end
+
+    def __set_result__(result)
+      raise Error::InvalidResultInstance unless result.is_a?(Result)
+      raise Error::ResultIsAlreadyDefined if @__result
+
+      @__result = result
+    end
+
+    private
+
+      def __call
+        result = call!
+
+        return result if result.is_a?(Result)
+
+        raise Error::UnexpectedResult.new(self.class)
+      end
+
+      def __get_result__
+        @__result ||= Result.new
+      end
+
+      def Success(arg = :ok)
+        value, type = block_given? ? [yield, arg] : [arg, :ok]
+
+        __get_result__.__set__(true, value, type, nil)
+      end
+
+      def Failure(arg = :error)
+        value = block_given? ? yield : arg
+        type = self.class.__failure_type(value, block_given? ? arg : :error)
+
+        __get_result__.__set__(false, value, type, self)
+      end
+  end
+end