related: https://github.com/spesmilo/electrum/issues/6889
This fixes the case where the user quits by pressing Ctrl+C,
and some other minor things.
There is still another issue that sometimes causes a segfault during shutdown...
see #7158
```
$ ./contrib/pull_locale
Found 260 files to translate
Generate template
electrum/gui/qt/installwizard.py:265: warning: Empty msgid. It is reserved by GNU gettext:
gettext("") returns the header entry with
meta information, not the empty string.
electrum/gui/qt/channels_list.py:49: warning: Empty msgid. It is reserved by GNU gettext:
gettext("") returns the header entry with
meta information, not the empty string.
```
Previously the min() was passed lightning amounts and on-chain amounts mixed;
which is conceptually a type error. It is now only passed on-chain amounts.
Due to the bug, we did not allow a swap to fully exhaust out "LN receive" capacity.
Now the max amt can be slighly larger.
- document SwapManager._get_recv_amount and SwapManager._get_send_amount
- change calculations so that they match the boltz-backend
- note that in the reverse swap case, the server does not care about the on-chain claim tx the client
needs to pay for. This introduced some implicit hacks and inconsistencies in the code in the past,
it is still a bit ugly but at least this is now explicit.
- SwapManager._get_recv_amount and SwapManager._get_send_amount are now proper inverses of each other
-----
Here are some code snippets to play around with in Qt console.
For the forward swap case:
```
from electrum import ecc; lnworker = wallet.lnworker; sm = lnworker.swap_manager
invoice = network.run_from_another_thread(lnworker.create_invoice(amount_msat=3000000*1000, message="swap", expiry=86400))[1]; request_data = {"type": "submarine", "pairId": "BTC/BTC", "orderSide": "sell", "invoice": invoice, "refundPublicKey": ecc.GENERATOR.get_public_key_bytes().hex()}
network.send_http_on_proxy('post', sm.api_url + '/createswap', json=request_data, timeout=30)
sm.get_send_amount(3000000, is_reverse=False)
sm.get_recv_amount(3026730, is_reverse=False)
```
For the reverse swap case:
```
from electrum import ecc; import os; lnworker = wallet.lnworker; sm = lnworker.swap_manager
request_data = {"type": "reversesubmarine", "pairId": "BTC/BTC", "orderSide": "buy", "invoiceAmount": 3000000, "preimageHash": os.urandom(32).hex(), "claimPublicKey": ecc.GENERATOR.get_public_key_bytes().hex()}
network.send_http_on_proxy('post', sm.api_url + '/createswap', json=request_data, timeout=30)
sm.get_recv_amount(3000000, is_reverse=True)
sm.get_send_amount(2974443, is_reverse=True)
```
It is not realistic to expect Electrum to be used as a watchtower
in GUI mode, and possibly counter-productive (may set wrong
expectations).
A proper watchtower should be configured as a daemon. The
documentation will be updated to reflect this change.
Note that this will not fix the value for already existing channels
that have been created with onchain backup; one would need a wallet_db
upgrade in order to fix them (probably not worth the effort).
- use_recoverable_channel is a user setting, available
only in standard wallets with a 'segwit' seed_type
- if enabled, 'lightning_xprv' is derived from seed
- otherwise, wallets use the existing 'lightning_privkey2'
Recoverable channels:
- channel recovery data is added funding tx using an OP_RETURN
- recovery data = 4 magic bytes + node id[0:16]
- recovery data is chacha20 encrypted using funding_address as nonce.
(this will allow to fund multiple channels in the same tx)
GUI:
- whether channels are recoverable is shown in wallet info dialog.
- if the wallet can have recoverable channels but has an old node_id,
users are told to close their channels and restore from seed
to have that feature.
