FFA

The system should enforce validation rules depending on whether the client is an individual or a company, ensuring the uniqueness of identification numbers during both client creation and client updates.

Acceptance Criteria

Scenario 1: Individual & Local Client – TAN Validation

Given the client type selected is Individual & Local
When the user enters a TAN during client creation or update
Then the system must validate that the TAN is unique
And prevent saving the client if the TAN already exists
And display an appropriate validation error message.

Scenario 2: Company Client & Local– BRN & VAT Validation

Given the client type selected is Company
When the user enters a BRN and/or VAT number during client creation or update
Then the system must validate that both BRN and VAT are unique
And prevent saving the client if either BRN or VAT already exists
And display an appropriate validation error message indicating which value is duplicated.

Scenario 3: Update Existing Client

Given an existing client is being updated
When the identification values (TAN, BRN, or VAT) are changed
Then the system must re-validate uniqueness against all other clients
And allow saving only if no duplicates are found.

Validation messages must be clear and user-friendly

• Example:
  • “A client with this TAN already exists.”
  • “A client with this BRN/VAT already exists.”