feat: Withholding Tax Certificate button on Purchase Invoice

Shown while Apply Tax Withholding Amount is ticked on a saved, not cancelled invoice; downloads the certificate PDF in Thai.
2026-09-22 03:29:54 +00:00
parent a1ca8439fc
commit 2ee381f369
4 changed files with 53 additions and 1 deletions
@@ -20,6 +20,17 @@ file overrides the upstream Thai for the standard labels the print formats show.
 print formats embed Sarabun (`public/fonts`, OFL) so PDFs render Thai on servers
 without a Thai system font. Switch a user or the print language to `th` to use it.

+### Withholding tax certificate
+
+A Purchase Invoice with *Apply Tax Withholding Amount* gets a **Withholding Tax Certificate**
+button that downloads the Revenue Department's Sec. 50 bis form (หนังสือรับรองการหักภาษี ณ ที่จ่าย,
+two copies) as a PDF: the *Withholding Tax Certificate* print format lays the invoice's data
+over the official form (`public/images`). The row the payment is reported on comes from
+*Type of Income Paid* on the Tax Withholding Category (set for the shipped categories; pick it
+for your own), and the ภ.ง.ด. return is ticked from the Supplier's type: ภ.ง.ด.53 for juristic
+payees, ภ.ง.ด.1ก / 2 / 3 by income type for individuals. เล่มที่ / เลขที่ (certificate book
+numbers) and ลำดับที่ (the line in the return) are left for the accountant.
+
 ### Contributing

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