WBTC (Re7 xBTC Pool)
  ↓ Supply as collateral
Borrow USDC (50% LTV)
  ↓ Deploy to yield
Vesu PRIME USDC Pool
  ↓
Spread = USDC Supply APY - USDC Borrow APY + BTCFi STRK Rewards

vesu.modify_position(ModifyPositionParams {
    collateral_asset: wbtc_addr,
    debt_asset: usdc_addr,
    user: vault_address,
    collateral: Amount { /* WBTC amount */ },
    debt: Amount { /* USDC amount, positive = borrow */ },
});

usdc_pool.modify_position(ModifyPositionParams {
    collateral_asset: usdc_addr,
    debt_asset: usdc_pool_debt_asset,  // Valid registered asset (no debt)
    user: vault_address,
    collateral: Amount { /* USDC amount */ },
    debt: Amount { /* zero */ },
});

let pragma = IPragmaOracleDispatcher { contract_address: oracle_addr };
let price_response = pragma.get_data_median(DataType::SpotEntry(0x4254432f555344));
let btc_price: u256 = price_response.price.into();  // 8 decimals

// USDC to borrow = wbtc_sats * btc_price * 50 / 10^12
let usdc_borrow = (amount * btc_price * 50) / 1000000000000;

let swap_params: Array<felt252> = array![
    token0, token1,              // WBTC, USDC (sorted by address)
    0x20c49ba5e353f80000000000000000, // fee 0.05%
    0x3e8,                       // tick_spacing 1000
    0x0,                         // extension
    0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF, // sqrt_ratio_limit (max)
];

import { Contract } from 'starknet'

const deltaNeutralVault = new Contract(deltaNeutralABI, deltaNeutralAddress, account)
const wbtc = new Contract(erc20ABI, wbtcAddress, account)

// Check minimum deposit
const minDeposit = await deltaNeutralVault.min_deposit()
console.log('Min deposit:', minDeposit / 1e8, 'WBTC')

// Deposit (auto-borrows + deploys USDC)
const amount = 10_000_000n // 0.1 WBTC
await wbtc.approve(deltaNeutralAddress, amount)
await deltaNeutralVault.deposit(amount, account.address)

// Check yvBTC-DN balance
const shares = await deltaNeutralVault.balance_of(account.address)

// Strategy info: (wbtc_collateral, usdc_debt, 0, paused)
const [wbtcColl, usdcDebt, _, paused] = await deltaNeutralVault.get_strategy_info()

console.log('WBTC collateral:', wbtcColl / 1e8)
console.log('USDC debt:', usdcDebt / 1e6)

// USDC deployed to PRIME pool
const usdcDeployed = await deltaNeutralVault.get_usdc_deployed()
console.log('USDC in PRIME pool:', usdcDeployed / 1e6)

// Verify 50% LTV
const btcPrice = 95000 // Example: $95k/BTC
const collateralValue = (wbtcColl / 1e8) * btcPrice
const ltv = (usdcDebt / 1e6) / collateralValue
console.log('LTV:', (ltv * 100).toFixed(2) + '%')  // Should be ~50%

// Fetch Vesu pool APYs from API
const vesuAPI = 'https://api.vesu.xyz/pools'
const pools = await fetch(vesuAPI).then(r => r.json())

const re7xBTC = pools.find(p => p.pool_id === '0x03a8416bf20d036df5b1cf3447630a2e1cb04685f6b0c3a70ed7fb1473548ecf')
const primeUSDC = pools.find(p => p.pool_id === '0x03976cac265a12609934089004df458ea29c776d77da423c96dc761d09d24124')

const usdcBorrowAPY = re7xBTC.usdc_borrow_apy  // Cost
const usdcSupplyAPY = primeUSDC.usdc_supply_apy // Revenue
const btcfiRewardsAPY = 5.0 // Example STRK rewards

const netSpread = usdcSupplyAPY - usdcBorrowAPY + btcfiRewardsAPY
console.log('Net yield spread:', netSpread.toFixed(2) + '% APY')

// Withdraw all (triggers flash loan unwind)
const maxWithdraw = await deltaNeutralVault.max_withdraw(account.address)
await deltaNeutralVault.withdraw(maxWithdraw, account.address, account.address)

// Flash loan process:
// 1. Withdraw ALL USDC from PRIME pool (~$50 if started with 0.1 WBTC)
// 2. Flash loan $0.50 USDC to cover rounding gap
// 3. Repay $50 USDC debt to Re7 + withdraw 0.1 WBTC collateral
// 4. Swap 0.001 WBTC -> $0.95 USDC (enough to repay flash loan)
// 5. User receives ~0.099 WBTC

// Monitor liquidation risk
const vesuPool = new Contract(vesuPoolABI, re7xBTCPoolAddress, provider)
const [position, collValue, debtValue] = await vesuPool.position(
  wbtcAddress,        // collateral_asset
  usdcAddress,        // debt_asset
  deltaNeutralAddress // user (vault)
)

// Health factor = (collateral * LT) / debt
// LT (liquidation threshold) ≈ 70% for Re7 xBTC USDC debt
const healthFactor = (collValue * 70n) / (debtValue * 100n)
console.log('Health factor:', Number(healthFactor) / 100)

// Safe: health > 1.4
// Caution: health 1.0-1.4
// Danger: health < 1.0 (liquidation imminent)