Disable rebalance/swap suggestions attached to requests/invoices if there is an ongoing task.
Note: This assumes that all tasks are lightning payments, which is true for the moment.
These methods return a list of channels that can be rebalanced,
in order to receive or send a given amount.
Also add 'channels' parameter to submarine swaps.
Previously, swaps were not considering which channel to use.
When we do not have liquidity to pay an invoice:
- add 'rebalance' option in order to pay an invoice
- use the suggested channel in the 'swap' option
When we do not have the liquidity to receive an invoice:
- add 'Rebalance' and 'Swap' buttons to the receive tab
I believe lightning requests created before https://github.com/spesmilo/electrum/pull/7730
can have an amount of None - ones created after have amount 0 instead.
We could do a wallet db upgrade potentially.
Regardless, the type hint is `get_amount_sat(self) -> Union[int, str, None]`,
so None should be handled. (well, arguably "!" should be handled too...)
```
E | gui.qt.exception_window.Exception_Hook | exception caught by crash reporter
Traceback (most recent call last):
File "...\electrum\electrum\gui\qt\request_list.py", line 101, in item_changed
self.parent.show_receive_request(req)
File "...\electrum\electrum\gui\qt\main_window.py", line 1279, in show_receive_request
URI = req.get_bip21_URI(lightning=bip21_lightning)
File "...\electrum\electrum\invoices.py", line 164, in get_bip21_URI
amount = int(self.get_amount_sat())
TypeError: int() argument must be a string, a bytes-like object or a real number, not 'NoneType'
```
```
E | gui.qt.exception_window.Exception_Hook | exception caught by crash reporter
Traceback (most recent call last):
File "...\electrum\electrum\gui\qt\request_list.py", line 101, in item_changed
self.parent.show_receive_request(req)
File "...\electrum\electrum\gui\qt\main_window.py", line 1281, in show_receive_request
can_receive_lightning = self.wallet.lnworker and req.get_amount_sat() <= self.wallet.lnworker.num_sats_can_receive()
TypeError: '<=' not supported between instances of 'NoneType' and 'decimal.Decimal'
```
follow-up https://github.com/spesmilo/electrum/pull/7818
- note it matters whether a sender pays us end-to-end-trampoline or just via legacy
- consider: Alice has 0.1 BTC recv cap in chan1 and 1 BTC recv cap in chan2, both with border-node T1
- if sender is paying e2e trampoline, it can realistically pay even ~1.1 BTC, as T1 can resplit the HTLCs
- if sender is paying legacy, it will have a hard time trying to pay more than 1 BTC, in practice
- although note if T1 has implemented non-strict-forwarding (see BOLT-04), achieving 1 BTC is easy,
as T1 can redirect HTLCs (but cannot split them, in this case)
- to make num_sats_can_receive realistic, it assumes the legacy case
- To calc num_sats_can_receive, we sort our channels in decreasing order of receive-capacities, iterate over them
and calculate a running sum - we stop adding channels when the next chan's recv cap is small compared to
the running total.
- When putting routing hints in an invoice, we do the same, with the added condition that we keep adding channels
if their recv cap is larger than the invoice amount.
- consider: Alice has 0.1 BTC recv cap in chan1 with Bob, and 1 BTC recv cap in chan2 with Carol
- if Alice wants to recv 100 sats, it is useful to add hints for both channels into the invoice, for redundancy
- if Alice wants to recv 0.9 BTC, it is questionable whether adding the smaller chan is useful - the code here won't add it
- increase MPP_RECEIVE_CUTOFF from 5 to 20 percent
- filter channels by node_id, not channel_id
- make num_sats_can_receive consistent with routing hints
return the max value allowed for legacy payments.
(that is, do not assume we can do MPP involving two trampolines)
This reverts fb6047ec46
Reason: num_sats_can_send may be used to decide the amount
we put in a new channel.
The Qt GUI refreshes all tabs on 'blockchain_updated', which is expensive for very large wallets.
Previously, on every new block, the GUI would get one notification for each connected interface,
now only the fastest interface triggers it.
(was testing with a wallet where refreshing all tabs takes 15 seconds, and 10*15 seconds is
even more annoying...)
