Review, finalize, and harden core trade protocol and code

[woodser]

There are many details to consider, finalize, and harden in the core trade protocol and code.

Priorities

• stress test
• implement scheduling for trades, other
• trade completion refactoring
• auto start seed node
• auto start funding wallet
• never wait for onArrived() or ack in protocols? (ProcessDepositResponse, ArbittratorSendsInitTrade*, ProcessInitMultisigRequest)
• allow node address to change; temp node address vs trusting/persisting into trade model
• test recovery from disconnecting or sleeping at various stages (balances stop updating)
• understand how arbitrator key is revoked, ensure new trader can verify past signatures and know if revoked (see bannedDisputeAgents)
• arbitrator api to register keys and resolve dispute?
• all api calls denominated in xmr atomic units
• show percent progress syncing daemon and wallet on startup
• wallet rpc authentication based on user/wallet password?
• test offers with trade range
• allow offers with multiple payment methods?
• do not update offers which would invalidate arbitrator signature (OpenOfferManager.maybeUpdatePersistedOffers())
• arbitrator TradeStepView errors / payment started button during trade
• connection manager autodetect peer connections
• signatures can be bytes per DipsuteResult.abitrator_signature
• btc atomic swaps
• funding wallet needs manually funded if cannot mine to it
• in offer counterCurrencyCode='XMR', baseCurrencyCode='ETH' ?
• CurrencyUtil:435 base currency and counter currency switched
• loss of precision handling BigInteger as long? e.g. XmrBalanceInfo? switch to strings in pb?
• test creating hundreds of new deposit addresses
• switch to native wallets?
• arbitrator broadcasts reserve tx if offer opened with same tx key within e.g. 1 second
• changeWallet() opens and syncs every wallet at once
• limit maximum number of wallets open at a time
• increase sync period (e.g. 10 or 15 seconds) for remote daemon connections
• backup multisig wallets of open trades
• "We found an outdated addressEntry for openOffer" for past trades
• delete multisig wallets if payout not confirmed after X blocks or when payout tx unlocks
• test that funds unreserve if arbitrator doesn't sign offer
• bitcoinj warning about threading
• full code refactor from big picture architecture
• use proof of reserves instead of specific key images?
• performance analysis of initializing trade
• TradeManager.closeDisputedTrade() should be called by arbitrator when dispute closed
• ArbitratorSendsInitTradeAndMultisigRequests sends multisig requests on ack but should skip if maker not reserved
• test completing trade with peers offline between messages
• switch ui tests to logging library
• send PayoutTxPublishedMessage to peer and arbitrator once signed
• test resolving dispute after payment started
• refactor dispute resolution; dispute opener includes updated multisig hex, arbitrator sends payout tx and updated multisig hex to opener, opener signs, broadcasts payout, and sends response / PayoutTxPublishedMessage
• optimize keeping wallets open and syncing, or syncing on unlock and then not re-syncing
• ensure OPenDispute ack comes back before re-opening/syncing wallet; analyze when all all wallets opened, closed, synced

Trade Completion

• review payout process
• Certify and tabulate completed trades #143
• support arbitration fee and reimbursing trader fee
• verify payout txs
• accurate fee estimation for tx verification
• close arbitrator trade at completion
• test arbitrator trade state in api tests
• don't delete trade wallets until payout tx unlocks

Optimizations / Performance

• optimize offer key image verification (only verify offers presented to ui? batch key image verification?)
• optimize number of open wallets and refresh period, especially arbitrator (see TradeManager.initPersistedTrades(), XmrWalletService.getMultisigWallet())

API Functions

• Add API functions to open and resolve disputes [$500] #161
• Add API functions to initialize Haveno account [$1500] #136
• Add API functions to start and stop local Monero node [$300] #137
• Add API functions to manage Monero daemon connections [$1000] #138
• Add API function to get market prices for all trade pairs [$250] #139
• Add API function to get market depth data of a trade pair [$250] #140
• Add API functions to get wallet transfers and withdraw funds [$400] #141
• Add API functions to support trade chat [$400] #142
• Add API function to receive notifications [$300] #147

Needs Consideration

• completely replace errorMessageHandler with regular exception handling
• send payment info on deposit unlock instead of deposit broadcast?
• clarify arbitrator/mediator/refund agent terminology and use throughout application
• switch base unit long from centineros to atomic units
• "No refund agents available" after idling
• "We found a closed trade with locked up funds" error
• "Wallet missing deposit tx" error
• "We had an old offer in the list with the same offer id"
• one TraderProtocol which supports maker, taker, buyer, seller methods to prevent duplicate implementations?
• flatten ProcessModel into Trade / other model refactors?
• refactor State/Phase for CleanupTradeableOnFault
• test retaking failed trade. change naming convention and create new multisig wallet or replace? cannot reuse
• TradeDataValidation.validateDepositInputs() needs updated for XMR, consolidate tx validation there?
• Create multisigs as offsets from main mnemonic, allow users to recreate multisig?

Note additional core todos are throughout the code prefixed with TODO (woodser).

[erciccione]

pinging @haveno-dex/developers for inputs.

[erciccione]

removing needs:discussion label. As this is an internal todo listi and some of its content will be split into single issues later on.