Added is_decryped and working on documentation

.gitignore

@@ -2,3 +2,4 @@
 /deps
 erl_crash.dump
 *.ez
+docs

lib/safetybox.ex

@@ -1,14 +1,41 @@
 defmodule Safetybox do
 
+  @moduledoc """
+  # Safetybox a collection of security oriented functions
+  ## Dependency
+      { :safetybox, "~> 0.1" }
+  ## Usage
+  ### API
+      pwd = Safetybox.encrypt("helloworld")
+
+      Safetybox.is_decrypted("goodbyeworld", pwd) # > returns false
+      Safetybox.is_decrypted("helloworld", pwd) # > returns true
+
+  ## Author
+  Copyright © 2014 Andrew Forward
+  @a4word,  [email protected]
+  Licensed under MIT.
+  """
+
   # Taken from https://gist.github.com/10nin/5713366
   def encrypt(nil), do: encrypt("")
-  def encrypt(str) do
-    :crypto.hash(:md5, str)
+
+  @doc """
+  Convert a plaintext string into an encrypted string, for example
+      Safetybox.encrypt("helloworld")
+  """
+  def encrypt(plaintext) do
+    :crypto.hash(:md5, plaintext)
       |> :erlang.bitstring_to_list
       |> Enum.map(&(:io_lib.format("~2.16.0b", [&1])))
       |> List.flatten
       |> :erlang.list_to_bitstring
   end
 
+  @doc """
+  Compare a plaintext string to it's encrypted version to test if they match.
+      Safetybox.is_decrypted("helloworld", "dasdf!@#CASD")
+  """
+  def is_decrypted(plaintext, encrypted), do: encrypt(plaintext) == encrypted
 
 end

mix.exs

@@ -4,9 +4,12 @@ defmodule Safetybox.Mixfile do
   def project do
     [
       app: :safetybox,
-      version: "0.0.1",
+      version: "0.0.2",
       elixir: "~> 1.0",
       deps: deps,
+
+      name: "safetybox",
+      source_url: "https://github.com/aforward/safetybox",
       package: [
         contributors: ["Andrew Forward"],
         licenses: ["MIT"],
@@ -35,6 +38,9 @@ defmodule Safetybox.Mixfile do
   #
   # Type `mix help deps` for more examples and options
   defp deps do
-    []
+    [
+      {:ex_doc, "~> 0.6", only: :dev},
+      {:earmark, "~> 0.1"},
+    ]
   end
 end

mix.lock

@@ -0,0 +1,2 @@
+%{"earmark": {:hex, :earmark, "0.1.12"},
+  "ex_doc": {:hex, :ex_doc, "0.6.2"}}

test/safetybox_test.exs

@@ -12,4 +12,18 @@ defmodule SafetyboxTest do
     assert S.encrypt("andrew") == S.encrypt("andrew")
   end
 
+  test "is_decrypted against encrypted value" do
+    assert S.is_decrypted("helloworld", "XXX") == false
+    assert S.is_decrypted("helloworld", S.encrypt("andrew")) == false
+    assert S.is_decrypted("helloworld", S.encrypt("helloworld")) == true
+  end
+
+  test "is_decrypted should handle nil" do
+    assert S.is_decrypted(nil, "XXX") == false
+    assert S.is_decrypted("helloworld", nil) == false
+    assert S.is_decrypted(nil, nil) == false
+    assert S.is_decrypted(nil, S.encrypt(nil)) == true
+    assert S.is_decrypted("", S.encrypt("")) == true
+  end
+
 end