refactor: separate OauthCallbackController

app/controllers/oauth_callback_controller.rb

@@ -0,0 +1,40 @@
+class OauthCallbackController < ApplicationController
+  def show
+    @response = oauth_client.auth_code.get_token(
+      oauth_code,
+      redirect_uri: "#{base_url}/#{provider_name}/callback"
+    )
+
+    handle_response
+  rescue StandardError => e
+    ChatwootExceptionTracker.new(e).capture_exception
+    redirect_to '/'
+  end
+
+  private
+
+  def oauth_code
+    params[:code]
+  end
+
+  def base_url
+    ENV.fetch('FRONTEND_URL', 'http://localhost:3000')
+  end
+
+  def parsed_body
+    @parsed_body ||= Rack::Utils.parse_nested_query(@response.raw_response.body)
+  end
+
+  # These methods should be implemented in the subclasses
+  def oauth_client
+    raise NotImplementedError
+  end
+
+  def provider_name
+    raise NotImplementedError
+  end
+
+  def handle_response
+    raise NotImplementedError
+  end
+end