package trader

import (
	"fmt"
	"nofx/logger"
	"nofx/store"
	"sync"
	"time"
)

// PositionSyncManager Position status synchronization manager
// Responsible for periodically synchronizing exchange positions, detecting manual closures and other changes
type PositionSyncManager struct {
	store        *store.Store
	interval     time.Duration
	stopCh       chan struct{}
	wg           sync.WaitGroup
	traderCache  map[string]Trader                    // trader_id -> Trader instance cache
	configCache  map[string]*store.TraderFullConfig   // trader_id -> config cache
	cacheMutex   sync.RWMutex
}

// NewPositionSyncManager Create position synchronization manager
func NewPositionSyncManager(st *store.Store, interval time.Duration) *PositionSyncManager {
	if interval == 0 {
		interval = 10 * time.Second
	}
	return &PositionSyncManager{
		store:       st,
		interval:    interval,
		stopCh:      make(chan struct{}),
		traderCache: make(map[string]Trader),
		configCache: make(map[string]*store.TraderFullConfig),
	}
}

// Start Start position synchronization service
func (m *PositionSyncManager) Start() {
	m.wg.Add(1)
	go m.run()
	logger.Info("📊 Position sync manager started")
}

// Stop Stop position synchronization service
func (m *PositionSyncManager) Stop() {
	close(m.stopCh)
	m.wg.Wait()

	// Clear cache
	m.cacheMutex.Lock()
	m.traderCache = make(map[string]Trader)
	m.configCache = make(map[string]*store.TraderFullConfig)
	m.cacheMutex.Unlock()

	logger.Info("📊 Position sync manager stopped")
}

// run Main loop
func (m *PositionSyncManager) run() {
	defer m.wg.Done()

	// Execute immediately on startup
	m.syncPositions()

	ticker := time.NewTicker(m.interval)
	defer ticker.Stop()

	for {
		select {
		case <-m.stopCh:
			return
		case <-ticker.C:
			m.syncPositions()
		}
	}
}

// syncPositions Synchronize all position statuses
func (m *PositionSyncManager) syncPositions() {
	// Get all OPEN status positions
	localPositions, err := m.store.Position().GetAllOpenPositions()
	if err != nil {
		logger.Infof("⚠️  Failed to get local positions: %v", err)
		return
	}

	if len(localPositions) == 0 {
		return
	}

	// Group by trader_id
	positionsByTrader := make(map[string][]*store.TraderPosition)
	for _, pos := range localPositions {
		positionsByTrader[pos.TraderID] = append(positionsByTrader[pos.TraderID], pos)
	}

	// Process each trader
	for traderID, traderPositions := range positionsByTrader {
		m.syncTraderPositions(traderID, traderPositions)
	}
}

// syncTraderPositions Synchronize positions for a single trader
func (m *PositionSyncManager) syncTraderPositions(traderID string, localPositions []*store.TraderPosition) {
	// Get or create trader instance
	trader, err := m.getOrCreateTrader(traderID)
	if err != nil {
		logger.Infof("⚠️  Failed to get trader instance (ID: %s): %v", traderID, err)
		return
	}

	// Get current exchange positions
	exchangePositions, err := trader.GetPositions()
	if err != nil {
		logger.Infof("⚠️  Failed to get exchange positions (ID: %s): %v", traderID, err)
		return
	}

	// Build exchange position map: symbol_side -> position
	exchangeMap := make(map[string]map[string]interface{})
	for _, pos := range exchangePositions {
		symbol, _ := pos["symbol"].(string)
		side, _ := pos["positionSide"].(string)
		if symbol == "" || side == "" {
			continue
		}
		key := fmt.Sprintf("%s_%s", symbol, side)
		exchangeMap[key] = pos
	}

	// Compare local and exchange positions
	for _, localPos := range localPositions {
		key := fmt.Sprintf("%s_%s", localPos.Symbol, localPos.Side)
		exchangePos, exists := exchangeMap[key]

		if !exists {
			// Exchange doesn't have this position → it has been closed
			m.closeLocalPosition(localPos, trader, "manual")
			continue
		}

		// Check if quantity is 0 or very small
		qty := getFloatFromMap(exchangePos, "positionAmt")
		if qty < 0 {
			qty = -qty // Short position quantity is negative
		}

		if qty < 0.0000001 {
			// Quantity is 0, position closed
			m.closeLocalPosition(localPos, trader, "manual")
		}
	}
}

// closeLocalPosition Mark local position as closed
func (m *PositionSyncManager) closeLocalPosition(pos *store.TraderPosition, trader Trader, reason string) {
	// Try to get last trade price as exit price
	exitPrice := pos.EntryPrice // Default to entry price

	// Try to get latest price from exchange
	if price, err := trader.GetMarketPrice(pos.Symbol); err == nil && price > 0 {
		exitPrice = price
	}

	// Calculate PnL
	var realizedPnL float64
	if pos.Side == "LONG" {
		realizedPnL = (exitPrice - pos.EntryPrice) * pos.Quantity
	} else {
		realizedPnL = (pos.EntryPrice - exitPrice) * pos.Quantity
	}

	// Update database
	err := m.store.Position().ClosePosition(
		pos.ID,
		exitPrice,
		"", // Manual close has no order ID
		realizedPnL,
		0,      // Manual close cannot get fee
		reason,
	)

	if err != nil {
		logger.Infof("⚠️  Failed to update position status: %v", err)
	} else {
		logger.Infof("📊 Position closed [%s] %s %s @ %.4f → %.4f, PnL: %.2f (%s)",
			pos.TraderID[:8], pos.Symbol, pos.Side, pos.EntryPrice, exitPrice, realizedPnL, reason)
	}
}

// getOrCreateTrader Get or create trader instance
func (m *PositionSyncManager) getOrCreateTrader(traderID string) (Trader, error) {
	m.cacheMutex.RLock()
	trader, exists := m.traderCache[traderID]
	m.cacheMutex.RUnlock()

	if exists && trader != nil {
		return trader, nil
	}

	// Need to create new trader instance
	config, err := m.getTraderConfig(traderID)
	if err != nil {
		return nil, fmt.Errorf("failed to get trader config: %w", err)
	}

	trader, err = m.createTrader(config)
	if err != nil {
		return nil, fmt.Errorf("failed to create trader instance: %w", err)
	}

	m.cacheMutex.Lock()
	m.traderCache[traderID] = trader
	m.cacheMutex.Unlock()

	return trader, nil
}

// getTraderConfig Get trader configuration
func (m *PositionSyncManager) getTraderConfig(traderID string) (*store.TraderFullConfig, error) {
	m.cacheMutex.RLock()
	config, exists := m.configCache[traderID]
	m.cacheMutex.RUnlock()

	if exists {
		return config, nil
	}

	// Get from database
	traders, err := m.store.Trader().ListAll()
	if err != nil {
		return nil, fmt.Errorf("failed to get trader list: %w", err)
	}

	var userID string
	for _, t := range traders {
		if t.ID == traderID {
			userID = t.UserID
			break
		}
	}

	if userID == "" {
		return nil, fmt.Errorf("trader not found: %s", traderID)
	}

	config, err = m.store.Trader().GetFullConfig(userID, traderID)
	if err != nil {
		return nil, err
	}

	m.cacheMutex.Lock()
	m.configCache[traderID] = config
	m.cacheMutex.Unlock()

	return config, nil
}

// createTrader Create trader instance based on configuration
func (m *PositionSyncManager) createTrader(config *store.TraderFullConfig) (Trader, error) {
	exchange := config.Exchange

	// Use exchange.ID to determine specific exchange, not exchange.Type (cex/dex)
	switch exchange.ID {
	case "binance":
		return NewFuturesTrader(exchange.APIKey, exchange.SecretKey, config.Trader.UserID), nil

	case "bybit":
		return NewBybitTrader(exchange.APIKey, exchange.SecretKey), nil

	case "okx":
		return NewOKXTrader(exchange.APIKey, exchange.SecretKey, exchange.Passphrase), nil

	case "hyperliquid":
		return NewHyperliquidTrader(exchange.SecretKey, exchange.HyperliquidWalletAddr, exchange.Testnet)

	case "aster":
		return NewAsterTrader(exchange.AsterUser, exchange.AsterSigner, exchange.AsterPrivateKey)

	case "lighter":
		if exchange.LighterAPIKeyPrivateKey != "" {
			return NewLighterTraderV2(
				exchange.LighterPrivateKey,
				exchange.LighterWalletAddr,
				exchange.LighterAPIKeyPrivateKey,
				exchange.Testnet,
			)
		}
		return NewLighterTrader(exchange.LighterPrivateKey, exchange.LighterWalletAddr, exchange.Testnet)

	default:
		return nil, fmt.Errorf("unsupported exchange: %s", exchange.ID)
	}
}

// InvalidateCache Invalidate cache
func (m *PositionSyncManager) InvalidateCache(traderID string) {
	m.cacheMutex.Lock()
	defer m.cacheMutex.Unlock()

	delete(m.traderCache, traderID)
	delete(m.configCache, traderID)
}

// getFloatFromMap Get float64 value from map
func getFloatFromMap(m map[string]interface{}, key string) float64 {
	if v, ok := m[key]; ok {
		switch val := v.(type) {
		case float64:
			return val
		case int64:
			return float64(val)
		case int:
			return float64(val)
		case string:
			var f float64
			fmt.Sscanf(val, "%f", &f)
			return f
		}
	}
	return 0
}