// INSTRUCTIONS: Replace handleBuy, handleSell, and handleReset in App.tsx with these versions
// Also add loadPortfolioFromBackend and call it in useEffect

import { executeTradeAPI, getPortfolioAPI, resetSimulationAPI, convertBackendPortfolio } from './services/tradingAPI'

// Add this state at the top of App component
const [isLoadingTrade, setIsLoadingTrade] = useState(false)

// Add this function to load portfolio on mount
const loadPortfolioFromBackend = useCallback(async () => {
  try {
    const backendPortfolio = await getPortfolioAPI()
    const converted = convertBackendPortfolio(backendPortfolio, currentPrice)
    setPortfolio(converted)
    console.log('✅ Portfolio loaded from backend:', converted)
  } catch (error) {
    console.error('Failed to load portfolio from backend:', error)
    // Fall back to default portfolio
    setPortfolio(recalcPortfolio(createInitialPortfolio(), currentPrice))
  }
}, [currentPrice])

// Add this useEffect to load on mount
useEffect(() => {
  if (syncToBackend) {
    loadPortfolioFromBackend()
  }
}, []) // Only run once on mount

// REPLACE handleBuy with this version
const handleBuy = useCallback(async (quantity: number) => {
  if (quantity <= 0 || Number.isNaN(quantity)) return
  
  if (!syncToBackend) {
    // Original in-memory logic (keep for backward compatibility)
    setPortfolio((prev) => {
      const cost = quantity * currentPrice
      if (cost > prev.cash) {
        alert('Insufficient cash for this order')
        return prev
      }
      const existing = prev.position
      const totalQuantity = existing ? existing.quantity + quantity : quantity
      const avgPrice = existing ? ((existing.avgPrice * existing.quantity + currentPrice * quantity) / totalQuantity) : currentPrice
      const trade: Trade = {
        id: `${Date.now()}-${Math.floor(Math.random() * 1000)}`,
        timestamp: Date.now(),
        action: 'BUY',
        quantity,
        price: currentPrice,
        total: Number(cost.toFixed(2)),
      }
      const updated: Portfolio = {
        ...prev,
        cash: Number((prev.cash - cost).toFixed(2)),
        position: {
          symbol: TRADING_SYMBOL,
          quantity: Number(totalQuantity.toFixed(4)),
          avgPrice: Number(avgPrice.toFixed(2)),
          currentPrice,
          unrealizedPnl: 0,
          unrealizedPnlPercent: 0,
        },
        trades: [trade, ...prev.trades].slice(0, 200),
      }
      return recalcPortfolio(updated, currentPrice)
    })
    return
  }

  // NEW: Backend-persisted logic
  setIsLoadingTrade(true)
  try {
    const response = await executeTradeAPI({
      action: 'BUY',
      quantity,
      price: currentPrice,
      symbol: TRADING_SYMBOL
    })
    
    // Reload portfolio from backend to ensure sync
    const backendPortfolio = await getPortfolioAPI()
    const converted = convertBackendPortfolio(backendPortfolio, currentPrice)
    setPortfolio(converted)
    
    console.log('✅ BUY trade executed and synced:', response.trade)
  } catch (error: any) {
    console.error('❌ Trade execution failed:', error)
    if (error.response?.data?.detail) {
      alert(`Trade failed: ${error.response.data.detail}`)
    } else {
      alert('Trade execution failed. Please try again.')
    }
  } finally {
    setIsLoadingTrade(false)
  }
}, [currentPrice, syncToBackend])

// REPLACE handleSell with this version
const handleSell = useCallback(async (quantity: number, reason = 'Manual exit') => {
  if (!syncToBackend) {
    // Original in-memory logic (keep for backward compatibility)
    setPortfolio((prev) => {
      const position = prev.position
      if (!position) {
        alert('No open position to close')
        return prev
      }
      const size = Math.min(quantity, position.quantity)
      if (size <= 0) return prev
      const proceeds = size * currentPrice
      const pnl = (currentPrice - position.avgPrice) * size
      const trade: Trade = {
        id: `${Date.now()}-${Math.floor(Math.random() * 1000)}`,
        timestamp: Date.now(),
        action: 'SELL',
        quantity: size,
        price: currentPrice,
        total: Number(proceeds.toFixed(2)),
        pnl: Number(pnl.toFixed(2)),
      }
      const remainingQty = Number((position.quantity - size).toFixed(4))
      const nextPosition = remainingQty > 0.0001
        ? { ...position, quantity: remainingQty, currentPrice }
        : null
      const updated: Portfolio = {
        ...prev,
        cash: Number((prev.cash + proceeds).toFixed(2)),
        position: nextPosition,
        trades: [trade, ...prev.trades].slice(0, 200),
      }
      if (reason.startsWith('Auto')) {
        console.info(reason)
      }
      return recalcPortfolio(updated, currentPrice)
    })
    if (!reason.startsWith('Manual')) {
      setAiAnalysis(null)
    }
    return
  }

  // NEW: Backend-persisted logic
  setIsLoadingTrade(true)
  try {
    // Check if we have a position
    const currentPortfolio = await getPortfolioAPI()
    if (!currentPortfolio.position) {
      alert('No open position to close')
      return
    }
    
    const size = Math.min(quantity, currentPortfolio.position.quantity)
    
    const response = await executeTradeAPI({
      action: 'SELL',
      quantity: size,
      price: currentPrice,
      symbol: TRADING_SYMBOL,
      notes: reason
    })
    
    // Reload portfolio from backend to ensure sync
    const backendPortfolio = await getPortfolioAPI()
    const converted = convertBackendPortfolio(backendPortfolio, currentPrice)
    setPortfolio(converted)
    
    console.log('✅ SELL trade executed and synced:', response.trade)
    
    if (reason.startsWith('Auto')) {
      console.info(reason)
    }
  } catch (error: any) {
    console.error('❌ Trade execution failed:', error)
    if (error.response?.data?.detail) {
      alert(`Trade failed: ${error.response.data.detail}`)
    } else {
      alert('Trade execution failed. Please try again.')
    }
  } finally {
    setIsLoadingTrade(false)
  }
  
  if (!reason.startsWith('Manual')) {
    setAiAnalysis(null)
  }
}, [currentPrice, syncToBackend])

// REPLACE handleReset with this version
const handleReset = useCallback(async () => {
  if (!syncToBackend) {
    // Original in-memory logic
    setPortfolio(recalcPortfolio(createInitialPortfolio(), currentPrice))
    setAiAnalysis(null)
    return
  }

  // NEW: Backend-persisted logic
  setIsLoadingTrade(true)
  try {
    const response = await resetSimulationAPI()
    const converted = convertBackendPortfolio(response.portfolio, currentPrice)
    setPortfolio(converted)
    setAiAnalysis(null)
    console.log('✅ Simulation reset and synced')
  } catch (error) {
    console.error('❌ Reset failed:', error)
    alert('Failed to reset simulation. Please try again.')
  } finally {
    setIsLoadingTrade(false)
  }
}, [currentPrice, syncToBackend])

// OPTIONAL: Add loading indicator in your Trade panel
// Show a spinner or disable buttons when isLoadingTrade is true