system: Allow preselecting inputs for atomic swaps.

basicswap/protocols/__init__.py

@@ -0,0 +1,12 @@
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2022 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+
+class ProtocolInterface:
+    swap_type = None
+
+    def getFundedInitiateTxTemplate(self, ci, amount: int, sub_fee: bool) -> bytes:
+        raise ValueError('base class')

basicswap/protocols/atomic_swap_1.py

@@ -10,12 +10,17 @@ from basicswap.db import (
 from basicswap.util import (
     SerialiseNum,
 )
+from basicswap.util.script import (
+    getP2WSH,
+)
 from basicswap.script import (
     OpCodes,
 )
 from basicswap.basicswap_util import (
+    SwapTypes,
     EventLogTypes,
 )
+from . import ProtocolInterface
 
 INITIATE_TX_TIMEOUT = 40 * 60  # TODO: make variable per coin
 ABS_LOCK_TIME_LEEWAY = 10 * 60
@@ -66,3 +71,43 @@ def redeemITx(self, bid_id, session):
     bid.initiate_tx.spend_txid = bytes.fromhex(txid)
     self.log.debug('Submitted initiate redeem txn %s to %s chain for bid %s', txid, ci_from.coin_name(), bid_id.hex())
     self.logEvent(Concepts.BID, bid_id, EventLogTypes.ITX_REDEEM_PUBLISHED, '', session)
+
+
+class AtomicSwapInterface(ProtocolInterface):
+    swap_type = SwapTypes.SELLER_FIRST
+
+    def getMockScript(self) -> bytearray:
+        return bytearray([
+            OpCodes.OP_RETURN, OpCodes.OP_1])
+
+    def getMockScriptScriptPubkey(self, ci) -> bytearray:
+        script = self.getMockScript()
+        return ci.get_p2wsh_script_pubkey(script) if ci._use_segwit else ci.get_p2sh_script_pubkey(script)
+
+    def promoteMockTx(self, ci, mock_tx: bytes, script: bytearray) -> bytearray:
+        mock_txo_script = self.getMockScriptScriptPubkey(ci)
+        real_txo_script = ci.get_p2wsh_script_pubkey(script) if ci._use_segwit else ci.get_p2sh_script_pubkey(script)
+
+        found: int = 0
+        ctx = ci.loadTx(mock_tx)
+        for txo in ctx.vout:
+            if txo.scriptPubKey == mock_txo_script:
+                txo.scriptPubKey = real_txo_script
+                found += 1
+
+        if found < 1:
+            raise ValueError('Mocked output not found')
+        if found > 1:
+            raise ValueError('Too many mocked outputs found')
+        ctx.nLockTime = 0
+
+        funded_tx = ctx.serialize()
+        return ci.signTxWithWallet(funded_tx)
+
+    def getFundedInitiateTxTemplate(self, ci, amount: int, sub_fee: bool) -> bytes:
+
+        script = self.getMockScript()
+        addr_to = ci.encode_p2wsh(getP2WSH(script)) if ci._use_segwit else ci.encode_p2sh(script)
+        funded_tx = ci.createRawFundedTransaction(addr_to, amount, sub_fee, lock_unspents=False)
+
+        return bytes.fromhex(funded_tx)

basicswap/protocols/xmr_swap_1.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-# Copyright (c) 2020 tecnovert
+# Copyright (c) 2020-2022 tecnovert
 # Distributed under the MIT software license, see the accompanying
 # file LICENSE or http://www.opensource.org/licenses/mit-license.php.
 
@@ -14,8 +14,10 @@ from basicswap.chainparams import (
 )
 from basicswap.basicswap_util import (
     KeyTypes,
+    SwapTypes,
     EventLogTypes,
 )
+from . import ProtocolInterface
 
 
 def addLockRefundSigs(self, xmr_swap, ci):
@@ -84,3 +86,7 @@ def getChainBSplitKey(swap_client, bid, xmr_swap, offer):
 
     key_type = KeyTypes.KBSF if bid.was_sent else KeyTypes.KBSL
     return ci_to.encodeKey(swap_client.getPathKey(offer.coin_from, offer.coin_to, bid.created_at, xmr_swap.contract_count, key_type, True if offer.coin_to == Coins.XMR else False))
+
+
+class XmrSwapInterface(ProtocolInterface):
+    swap_type = SwapTypes.XMR_SWAP