mango-v4-ui/hooks/useSolBalance.ts

import { TokenInstructions } from '@project-serum/serum'
import { useWallet } from '@solana/wallet-adapter-react'
import mangoStore from '@store/mangoStore'
import { useMemo } from 'react'
import { MIN_SOL_BALANCE } from 'utils/constants'

export default function useSolBalance() {
  const walletTokens = mangoStore((s) => s.wallet.tokens)
  const { connected } = useWallet()
  const solBalance: number = useMemo(() => {
    return connected
      ? walletTokens.find((t) =>
          t.mint.equals(TokenInstructions.WRAPPED_SOL_MINT)
        )?.uiAmount || 0
      : 100
  }, [walletTokens])

  const maxSolDeposit: number = useMemo(() => {
    return solBalance - MIN_SOL_BALANCE
  }, [solBalance])

  return { solBalance, maxSolDeposit }
}