module EncryptedZip

# File lib/encryptedzip.rb, line 12
def self.create_encrypted_zip(options={})
  check_errors(options)
  password = generate_password
  create_password_file(password)

  create_zip(encrypted_filepath, options[:files])
  Zip::Archive.encrypt(encrypted_filepath, password)

  create_zip(options[:output_filepath], 
    [password_path, encrypted_filepath])

  clean_up
  options[:output_filepath]
end

# File lib/encryptedzip.rb, line 61
def self.check_errors(options)
  raise "You must set a public key file location" unless @public_key_file
  raise "Place a public key at #{@public_key_file}" unless File.exists? @public_key_file
  raise "You must supply an output filepath" unless options.has_key? :output_filepath
  raise "You must supply a list of files to encrypt" unless options.has_key? :files
end

# File lib/encryptedzip.rb, line 44
def self.clean_up
  File.delete(encrypted_filepath, password_path)
end

# File lib/encryptedzip.rb, line 57
def self.create_password_file(password)
  File.open(password_path, "wb") {|f| f.write(encrypt_string password)}
end

# File lib/encryptedzip.rb, line 36
def self.create_zip(filename, files)
  Zip::Archive.open(filename, Zip::CREATE) do |archive|
    files.each do |file|
      archive.add_file(file) 
    end
  end
end

# File lib/encryptedzip.rb, line 52
def self.encrypt_string(string)
  public_key = OpenSSL::PKey::RSA.new(File.read(public_key_file))
  cipher = public_key.public_encrypt(string)
end

# File lib/encryptedzip.rb, line 48
def self.generate_password
  SecureRandom.base64(85)
end