Feature: Add wallet export to Jade via QR

src/cryptoadvance/specter/devices/jade.py

@@ -1,7 +1,9 @@
 from .hwi_device import HWIDevice
 from .hwi.jade import JadeClient
 from .hwi.jade import enumerate as jade_enumerate
-from ..helpers import is_liquid
+from ..helpers import is_liquid, to_ascii20
+from ..util import bcur
+from binascii import b2a_base64
 
 
 class Jade(HWIDevice):
@@ -18,6 +20,8 @@ class Jade(HWIDevice):
     supports_hwi_multisig_display_address = True
     supports_multisig_registration = True
     liquid_support = True
+    exportable_to_wallet = True
+    wallet_export_type = "qr"
 
     @classmethod
     def get_client(cls, *args, **kwargs):
@@ -43,3 +47,54 @@ def create_psbts(self, base64_psbt, wallet):
         qr_psbt = wallet.fill_psbt(base64_psbt, non_witness=False, xpubs=False)
         psbts["qrcode"] = f"{self.supported_qr_code_format}:{qr_psbt}"
         return psbts
+
+    # Enables the export of a multisig wallet to a Jade via QR
+    def export_wallet(self, wallet):
+        if not wallet.is_multisig:
+            return None
+        # Jade uses ColdCard's style (assumes derivaion paths of the keys to be the same)
+        CC_TYPES = {"legacy": "BIP45", "p2sh-segwit": "P2WSH-P2SH", "bech32": "P2WSH"}
+        derivation = None
+        for k in wallet.keys:
+            if k in self.keys and k.derivation != "":
+                derivation = k.derivation.replace("h", "'")
+                break
+        if derivation is None:
+            return None
+        qr_string = """
+        Name: {}
+        Policy: {} of {}
+        Derivation: {}
+        Format: {}
+        Sorted: {}
+        """.format(
+            to_ascii20(wallet.name),
+            wallet.sigs_required,
+            len(wallet.keys),
+            derivation,
+            CC_TYPES[wallet.address_type],
+            not wallet.uses_multi,
+        )
+
+        for k in wallet.keys:
+            fingerprint = k.fingerprint
+            if fingerprint == "":
+                fingerprint = get_xpub_fingerprint(k.xpub).hex()
+            qr_string += "{}: {}\n".format(
+                fingerprint.upper(),
+                k.xpub,
+            )
+
+        qr_string = b2a_base64(qr_string.encode()).decode()
+        return f"ur-bytes:{qr_string}"
+
+        # Example output:
+        # """
+        # Name: MyWallet
+        # Policy: 2 of 3
+        # Derivation: m/48'/1'/0'/2'
+        # Format: P2WSH
+        # Sorted: False
+        # A1B2C3D4: tpubD6NzVbkrYhZ...
+        # F2E3D4C5: tpubE6NzVhkxF7Q...
+        # """