From a9c296c44ba3a226c00d520d2d8bd210abf2473a Mon Sep 17 00:00:00 2001
From: natsoni <natsoni@protonmail.com>
Date: Wed, 8 Jul 2026 11:18:17 +0200
Subject: [PATCH] Export isWitnessProgram function and add PSBT_GLOBAL

---
 frontend/src/app/shared/transaction.utils.ts | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/frontend/src/app/shared/transaction.utils.ts b/frontend/src/app/shared/transaction.utils.ts
index 8bb4fcbc4..1b27476ce 100644
--- a/frontend/src/app/shared/transaction.utils.ts
+++ b/frontend/src/app/shared/transaction.utils.ts
@@ -713,7 +713,7 @@ function isNonStandardLegacySigops(tx: Transaction, height?: number, network?: s
 // A witness program is any valid scriptpubkey that consists of a 1-byte push opcode
 // followed by a data push between 2 and 40 bytes.
 // https://github.com/bitcoin/bitcoin/blob/2c79abc7ad4850e9e3ba32a04c530155cda7f980/src/script/script.cpp#L224-L240
-function isWitnessProgram(scriptpubkey: string): false | { version: number, program: string } {
+export function isWitnessProgram(scriptpubkey: string): false | { version: number, program: string } {
   if (scriptpubkey.length < 8 || scriptpubkey.length > 84) {
     return false;
   }
@@ -1456,6 +1456,11 @@ function fromBuffer(buffer: Uint8Array, network: string, inputs?: PsbtKeyValueMa
 export type PsbtKeyValue = { keyData: Uint8Array; value: Uint8Array; };
 export type PsbtKeyValueMap = Map<number, PsbtKeyValue[]>;
 
+export const PSBT_GLOBAL = {
+  UNSIGNED_TX: 0x00,
+  GENERIC_SIGNED_MESSAGE: 0x09,
+};
+
 export const PSBT_IN = {
   NON_WITNESS_UTXO: 0x00,
   WITNESS_UTXO: 0x01,
@@ -1601,9 +1606,10 @@ function decodePsbt(psbtBuffer: Uint8Array): { rawTx: Uint8Array; inputs: PsbtKe
  * @param rawTx - The unsigned transaction as Uint8Array
  * @param inputs - Array of input maps containing key-value pairs for each input
  * @param outputs - Array of output maps containing key-value pairs for each output
+ * @param globals - Global key-value pairs for the PSBT
  * @returns PSBT buffer as Uint8Array
  */
-export function encodePsbt(rawTx: Uint8Array, inputs: PsbtKeyValueMap[], outputs: PsbtKeyValueMap[]): Uint8Array {
+export function encodePsbt(rawTx: Uint8Array, inputs: PsbtKeyValueMap[], outputs: PsbtKeyValueMap[], globals: PsbtKeyValueMap = new Map()): Uint8Array {
   const result: number[] = [];
 
   // Magic bytes: "psbt" in ASCII
@@ -1633,7 +1639,12 @@ export function encodePsbt(rawTx: Uint8Array, inputs: PsbtKeyValueMap[], outputs
 
   // GLOBAL MAP
   // Add unsigned transaction (key type 0x00)
-  writeKeyValue(0x00, new Uint8Array(), rawTx);
+  writeKeyValue(PSBT_GLOBAL.UNSIGNED_TX, new Uint8Array(), rawTx);
+  for (const [keyType, items] of globals) {
+    for (const record of items) {
+      writeKeyValue(keyType, record.keyData, record.value);
+    }
+  }
 
   // End global map
   result.push(0x00);