Tally Invoice Automation via TDL

I need a TDL solution that removes all manual work from our current invoice flow in Tally. Using the ​standard Tally template, the code should:

• Create new sales invoices automatically from data we will supply through an importable CSV or XML (I am open to whichever native format you feel is easier to maintain).
• Validate each invoice against stock availability, tax rules and customer ledgers, stopping or flagging anything that fails predefined checks.
• Email the final, system-generated PDF to the customer contact saved in Tally the moment the invoice is accepted.

Please build the logic entirely in Tally Definition Language, keep it upgrade-safe for Tally Prime, and document every function so my in-house accountant can tweak parameters later.

Acceptance will be based on:
1. End-to-end run that generates, validates and emails ten sample invoices without user intervention.
2. Clear comments and a short README explaining how to deploy the TDL file, map import fields and edit validation rules.

If you have previous TDL snippets or a demo that shows similar automation, feel free to reference them; seeing working code speeds up selection.