How would you improve card-type detection?

Scenario

You have a service that needs to determine a credit/debit card network/type (e.g., Visa, Mastercard, AmEx, Discover, etc.) from the card number.

Today the logic is simplistic: it checks only the first few digits (a fixed prefix) and maps that prefix to a card type.

Question

How would you improve this approach so it is more accurate and maintainable in production?

Discuss:

• What data/logic you would use instead of (or in addition to) a few hard-coded starting digits.
• How you would handle new/updated ranges , overlaps, and unknown card types.
• How you would validate correctness and ensure safe rollout.

(No coding required; explain the design and reasoning.)