@startuml
skinparam BackgroundColor F0F0F0

participant "Application" as app
participant "ContactRecord" as rec
participant "contacts DB" as db

== Checking for duplicates ==

app -> rec : contacts to check\n(query::CheckContactsListDuplicates)
rec -> db : get numbers
db -> rec
rec -> rec : numbers comparison
rec -> app : duplicated contacts

== Merging contacts list to DB ==

app -> rec : contacts to merge\n(query::MergeContactsList)
rec -> db : get numbers
db -> rec
rec -> rec : numbers comparison

group number not found
    rec -> db : Add contact
end
group number found in db
    rec -> db : Update contact by overriding old data
end
rec -> app : status response

@enduml