require 'faraday'
require 'multi_json'

module OmniAuth
  module Strategies
    class GitLab
      include OmniAuth::Strategy

      option :fields, [:email]
      option :site, nil
      option :v, 'v3'
      option :uid_field, :email
      option :on_login, nil
      option :on_registration, nil
      option :on_failed_registration, nil

      def request_phase
        if options[:on_login]
          options[:on_login].call(self.env)
        else
          form = OmniAuth::Form.new(:title =>  (options[:title] || "Gitlab Verification"), :url => callback_path)
          
          form.text_field 'Email', 'email'
          form.password_field 'Password', 'password'
          form.button "Sign In"
          form.to_response
        end
      end

      def callback_phase
        return fail!(:invalid_credentials) unless identity
        super
      end
      
      uid{ identity['id'].to_s }
      info do
        {
          :name => identity['name'],
          :email => identity['email'],
          :nickname => identity['username']
        } 
      end
      
      credentials do
        { :token => identity['private_token'] }
      end
      
      extra do 
        { :raw_info => identity }
      end
      
      def identity
        @identity ||= begin
          conn = Faraday.new(:url => options[:site])
          resp = conn.post do |req|
            req.url "/api/#{options[:v]}/session"
            req.headers['Content-Type'] = 'application/json'
            req.params = { :email => request['email'], :password => request['password'] }
          end
          resp.success? ? MultiJson.decode(resp.body) : nil
        end 
      end
    end
  end
end


OmniAuth.config.add_camelization 'gitlab', 'GitLab'