Greptile Summary

This PR fixes a bug where SOL wallets returned by CoinPay's /api/oauth/userinfo endpoint — shaped as {address, chain: "SOL"} with no symbol field — were not recognized by coinToPaymentCurrency, causing invoices to fail with "Select a CoinPay receiving wallet". The fix adds coin.chain as the last fallback in the symbol OR-chain, so a wallet carrying only a chain identifier is now matched correctly.

• Two-line change in coinToPaymentCurrency: normalizeCoinSymbol(coin.chain) is appended as the fifth fallback for the symbol variable, after coin.id. It is only reached when all of symbol, code, currency, and id are absent.
• No impact on multi-token chains (USDT/USDC): For those coins the symbol field must already be set to "USDT"/"USDC" for correct chain disambiguation; the new fallback does not interfere with that logic because coin.chain is only consulted when the primary identifiers are all empty.

Confidence Score: 4/5

The change is a minimal, well-targeted fallback that resolves the stated SOL wallet recognition failure; safe to merge for native-coin wallets.

The two-line fix works correctly for any wallet where the only identifier is coin.chain and that chain maps directly to a single currency (SOL, ETH, BTC, POL). The one open question is whether the CoinPay userinfo endpoint also returns USDC/USDT wallets with only a chain field and no token symbol — if it does, those wallets would be mis-mapped to the native coin currency (e.g., "sol" instead of "usdc_sol"). Whether that edge case actually occurs depends on CoinPay API behaviour that cannot be confirmed from the code alone.

Only src/lib/coinpayportal.ts was changed; focus review on whether multi-token Solana/Polygon wallets from the userinfo endpoint carry a token symbol field alongside chain.

Important Files Changed

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["coinToPaymentCurrency(coin)"] --> B["Check directCurrency\n(coin.currency, coin.id, coin.code)"]
    B -- "Match in SUPPORTED_CURRENCIES" --> C["Return matched SupportedCurrency"]
    B -- "No match" --> D["Compute symbol\ncoin.symbol || coin.code ||\ncoin.currency || coin.id\n|| coin.chain ← NEW"]
    D --> E["Compute chain\ncoin.chain || coin.network\n|| coin.blockchain"]
    E --> F{symbol?}
    F -- "BTC/BCH/ETH/POL/SOL" --> G["Return single-asset currency\ne.g. 'sol', 'eth'"]
    F -- "USDT" --> H{"chain?\nPOL / SOL / ETH"}
    H --> I["Return 'usdt_pol' / 'usdt_sol' / 'usdt_eth' / 'usdt'"]
    F -- "USDC" --> J{"chain?\nPOL / ETH"}
    J --> K["Return 'usdc_pol' / 'usdc_eth' / 'usdc_sol'"]
    F -- "no match" --> L["Return null"]

_{Reviews (1): Last reviewed commit: "fix(coinpayportal): add coin.chain fallb..." | Re-trigger Greptile}