require 'omniauth'
require 'faraday'
require 'cgi'
require 'microformats2'

module OmniAuth
  module Strategies
    class IndieAuth
      include OmniAuth::Strategy

      option :name, 'indieauth'
      option :server, 'https://indieauth.com'
      option :client_id

      attr_accessor :me

      def redirect_uri
        full_host + script_name + callback_path
      end

      def request_phase
        puts redirect_uri
        redirect "#{options.server}/sign-in?redirect_uri=#{URI.encode_www_form_component(redirect_uri)}&client_id=#{URI.encode_www_form_component(options.client_id)}"
      end

      def callback_phase
        puts request.params.inspect

        conn = Faraday.new(:url => "#{options.server}/auth") do |faraday|
          faraday.request  :url_encoded             # form-encode POST params
        end
        response = Faraday.post "#{options.server}/auth", {
          :code => request.params['code'],
          :client_id => options.client_id,
          :redirect_uri => redirect_uri
        }
        puts response.body

        data = CGI::parse response.body

        if data['me'].length > 0
          @me = data['me'][0]
        else
          fail!(data['error'][0].to_sym, CallbackError.new(data['error'][0].to_sym, data['error_description'][0]))
        end

        super
      end

      uid do
        @me
      end

      info do
        data = {
          :url => @me,
          :name => @me.gsub(/https?:\/\//, '')
        }

        # Parse the url and look for an h-card to fill out the profile info
        begin
          src = Faraday.get @me
          m = Microformats2.parse src.body

          if m.card
            data[:name] = m.card.name.to_s if m.card.name
            data[:image] = m.card.photo.to_s if m.card.photo
          end
        rescue
          # Ignore errors
        end

        data
      end

      class CallbackError < StandardError
        attr_accessor :error, :error_reason, :error_uri

        def initialize(error, error_reason = nil, error_uri = nil)
          self.error = error
          self.error_reason = error_reason
          self.error_uri = error_uri
        end

        def message
          [error, error_reason, error_uri].compact.join(' | ')
        end
      end

    end
  end
end

OmniAuth.config.add_camelization 'indieauth', 'IndieAuth'