flow.puml

@startuml
<style>
activityDiagram {
  diamond {
    FontColor black
    BackgroundColor #ccf
  }
}
</style>

start
:Property owner submits
an __invitation form__ specifying
email address;
if (\n\nDoes User with given\nemail exist in the db?\n\n) then (yes)
	:Fetch User;
	:Create an invitation record in db
	(__with__ user_id);
	:Send invitation email to the User
	(click to accept the invitation);
else (no)
	:Create invitation record in db
	(__without__ user_id);
	:Send invitation email to the User
	(click to register account and accept the invitation);
endif

:User clicks an invitation link\n(token in URL);
:Fetch invitation record by the token;
if (\n\nDoes the invitation exist?\n\n) then (yes)
	if (\n\nIs user_id present\nand\nUser exist in the db?\n\n) then (yes)
		:Associate the User with the property owner;
		:Delete the invitation record;
		:Redirect the User\nto the login page or to the dashboard;
		:Display:\nThe invitation has been confirmed;
		stop
	else (no)
		:Render a dedicated Register User page;
		note right
			Prompt User for password,
			Auto fill the already known fields.
			Email field is disabled (can not be changed)
			as it would complicate the logic.
		end note
		:Create User record;
		note right
			No need to send confirmation email
			(the fact that User clicked the invitation
			link is a confirmation)
		end note
		:Associate the User with the property owner;
		:Delete the invitation record;
		:Auto log in the User\nand redirect to the dashboard;
		:Display:\nThe invitation has been confirmed;
		stop
	endif
else (no)
	:Display:
	The invitation link is invalid,
	expired, or was already used;
end


@enduml