package api

import (
	"encoding/json"
	"fmt"
	"net/http"
	"nofx/decision"
	"nofx/market"
	"nofx/mcp"
	"nofx/store"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
)

// handleGetStrategies Get strategy list
func (s *Server) handleGetStrategies(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	strategies, err := s.store.Strategy().List(userID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to get strategy list: " + err.Error()})
		return
	}

	// Convert to frontend format
	result := make([]gin.H, 0, len(strategies))
	for _, st := range strategies {
		var config store.StrategyConfig
		json.Unmarshal([]byte(st.Config), &config)

		result = append(result, gin.H{
			"id":          st.ID,
			"name":        st.Name,
			"description": st.Description,
			"is_active":   st.IsActive,
			"is_default":  st.IsDefault,
			"config":      config,
			"created_at":  st.CreatedAt,
			"updated_at":  st.UpdatedAt,
		})
	}

	c.JSON(http.StatusOK, gin.H{
		"strategies": result,
	})
}

// handleGetStrategy Get single strategy
func (s *Server) handleGetStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	strategyID := c.Param("id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	strategy, err := s.store.Strategy().Get(userID, strategyID)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Strategy not found"})
		return
	}

	var config store.StrategyConfig
	json.Unmarshal([]byte(strategy.Config), &config)

	c.JSON(http.StatusOK, gin.H{
		"id":          strategy.ID,
		"name":        strategy.Name,
		"description": strategy.Description,
		"is_active":   strategy.IsActive,
		"is_default":  strategy.IsDefault,
		"config":      config,
		"created_at":  strategy.CreatedAt,
		"updated_at":  strategy.UpdatedAt,
	})
}

// handleCreateStrategy Create strategy
func (s *Server) handleCreateStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	var req struct {
		Name        string               `json:"name" binding:"required"`
		Description string               `json:"description"`
		Config      store.StrategyConfig `json:"config" binding:"required"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request parameters: " + err.Error()})
		return
	}

	// Serialize configuration
	configJSON, err := json.Marshal(req.Config)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to serialize configuration"})
		return
	}

	strategy := &store.Strategy{
		ID:          uuid.New().String(),
		UserID:      userID,
		Name:        req.Name,
		Description: req.Description,
		IsActive:    false,
		IsDefault:   false,
		Config:      string(configJSON),
	}

	if err := s.store.Strategy().Create(strategy); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create strategy: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"id":      strategy.ID,
		"message": "Strategy created successfully",
	})
}

// handleUpdateStrategy Update strategy
func (s *Server) handleUpdateStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	strategyID := c.Param("id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	// Check if it's a system default strategy
	existing, err := s.store.Strategy().Get(userID, strategyID)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Strategy not found"})
		return
	}
	if existing.IsDefault {
		c.JSON(http.StatusForbidden, gin.H{"error": "Cannot modify system default strategy"})
		return
	}

	var req struct {
		Name        string               `json:"name"`
		Description string               `json:"description"`
		Config      store.StrategyConfig `json:"config"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request parameters: " + err.Error()})
		return
	}

	// Serialize configuration
	configJSON, err := json.Marshal(req.Config)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to serialize configuration"})
		return
	}

	strategy := &store.Strategy{
		ID:          strategyID,
		UserID:      userID,
		Name:        req.Name,
		Description: req.Description,
		Config:      string(configJSON),
	}

	if err := s.store.Strategy().Update(strategy); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to update strategy: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Strategy updated successfully"})
}

// handleDeleteStrategy Delete strategy
func (s *Server) handleDeleteStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	strategyID := c.Param("id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	if err := s.store.Strategy().Delete(userID, strategyID); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to delete strategy: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Strategy deleted successfully"})
}

// handleActivateStrategy Activate strategy
func (s *Server) handleActivateStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	strategyID := c.Param("id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	if err := s.store.Strategy().SetActive(userID, strategyID); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to activate strategy: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Strategy activated successfully"})
}

// handleDuplicateStrategy Duplicate strategy
func (s *Server) handleDuplicateStrategy(c *gin.Context) {
	userID := c.GetString("user_id")
	sourceID := c.Param("id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	var req struct {
		Name string `json:"name" binding:"required"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request parameters: " + err.Error()})
		return
	}

	newID := uuid.New().String()
	if err := s.store.Strategy().Duplicate(userID, sourceID, newID, req.Name); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to duplicate strategy: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"id":      newID,
		"message": "Strategy duplicated successfully",
	})
}

// handleGetActiveStrategy Get currently active strategy
func (s *Server) handleGetActiveStrategy(c *gin.Context) {
	userID := c.GetString("user_id")

	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	strategy, err := s.store.Strategy().GetActive(userID)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "No active strategy"})
		return
	}

	var config store.StrategyConfig
	json.Unmarshal([]byte(strategy.Config), &config)

	c.JSON(http.StatusOK, gin.H{
		"id":          strategy.ID,
		"name":        strategy.Name,
		"description": strategy.Description,
		"is_active":   strategy.IsActive,
		"is_default":  strategy.IsDefault,
		"config":      config,
		"created_at":  strategy.CreatedAt,
		"updated_at":  strategy.UpdatedAt,
	})
}

// handleGetDefaultStrategyConfig Get default strategy configuration template
func (s *Server) handleGetDefaultStrategyConfig(c *gin.Context) {
	// Return default configuration structure for frontend to use when creating new strategies
	defaultConfig := store.StrategyConfig{
		CoinSource: store.CoinSourceConfig{
			SourceType:    "coinpool",
			UseCoinPool:   true,
			CoinPoolLimit: 30,
			UseOITop:      true,
			OITopLimit:    20,
			StaticCoins:   []string{},
		},
		Indicators: store.IndicatorConfig{
			Klines: store.KlineConfig{
				PrimaryTimeframe:     "5m",
				PrimaryCount:         30,
				LongerTimeframe:      "4h",
				LongerCount:          10,
				EnableMultiTimeframe: true,
				SelectedTimeframes:   []string{"5m", "15m", "1h", "4h"},
			},
			EnableEMA:         true,
			EnableMACD:        true,
			EnableRSI:         true,
			EnableATR:         true,
			EnableVolume:      true,
			EnableOI:          true,
			EnableFundingRate: true,
			EMAPeriods:        []int{20, 50},
			RSIPeriods:        []int{7, 14},
			ATRPeriods:        []int{14},
		},
		RiskControl: store.RiskControlConfig{
			MaxPositions:       3,
			BTCETHMaxLeverage:  5,
			AltcoinMaxLeverage: 5,
			MinRiskRewardRatio: 3.0,
			MaxMarginUsage:     0.9,
			MaxPositionRatio:   1.5,
			MinPositionSize:    12,
			MinConfidence:      75,
		},
		PromptSections: store.PromptSectionsConfig{
			RoleDefinition: `# You are a professional cryptocurrency trading AI

You focus on technical analysis and risk management, making rational trading decisions based on market data.
Your goal is to capture high-probability trading opportunities while controlling risk.`,
			TradingFrequency: `# ⏱️ Trading Frequency Awareness

- Excellent traders: 2-4 trades per day ≈ 0.1-0.2 trades per hour
- >2 trades per hour = overtrading
- Single position holding time ≥30-60 minutes
If you find yourself trading every cycle → standards too low; if closing positions <30 minutes → too impatient.`,
			EntryStandards: `# 🎯 Entry Standards (Strict)

Only enter when multiple signals align:
- Clear trend direction (EMA alignment, price position)
- Momentum confirmation (MACD, RSI cooperation)
- Moderate volatility (ATR reasonable range)
- Volume-price coordination (volume supports direction)

Avoid: single indicator, conflicting signals, sideways consolidation, reopening immediately after closing.`,
			DecisionProcess: `# 📋 Decision Process

1. Check positions → Should take profit/stop loss
2. Scan candidate coins + multiple timeframes → Are there strong signals
3. Evaluate risk-reward ratio → Does it meet minimum requirements
4. Write chain of thought first, then output structured JSON`,
		},
	}

	c.JSON(http.StatusOK, defaultConfig)
}

// handlePreviewPrompt Preview prompt generated by strategy
func (s *Server) handlePreviewPrompt(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	var req struct {
		Config          store.StrategyConfig `json:"config" binding:"required"`
		AccountEquity   float64              `json:"account_equity"`
		PromptVariant   string               `json:"prompt_variant"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request parameters: " + err.Error()})
		return
	}

	// Use default values
	if req.AccountEquity <= 0 {
		req.AccountEquity = 1000.0 // Default simulated account equity
	}
	if req.PromptVariant == "" {
		req.PromptVariant = "balanced"
	}

	// Create strategy engine to build prompt
	engine := decision.NewStrategyEngine(&req.Config)

	// Build system prompt (using built-in method from strategy engine)
	systemPrompt := engine.BuildSystemPrompt(
		req.AccountEquity,
		req.PromptVariant,
	)

	// Get list of available prompt templates
	templateNames := decision.GetAllPromptTemplateNames()

	c.JSON(http.StatusOK, gin.H{
		"system_prompt":       systemPrompt,
		"prompt_variant":      req.PromptVariant,
		"available_templates": templateNames,
		"config_summary": gin.H{
			"coin_source":      req.Config.CoinSource.SourceType,
			"primary_tf":       req.Config.Indicators.Klines.PrimaryTimeframe,
			"btc_eth_leverage": req.Config.RiskControl.BTCETHMaxLeverage,
			"altcoin_leverage": req.Config.RiskControl.AltcoinMaxLeverage,
			"max_positions":    req.Config.RiskControl.MaxPositions,
		},
	})
}

// handleStrategyTestRun AI test run (does not execute trades, only returns AI analysis results)
func (s *Server) handleStrategyTestRun(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Unauthorized"})
		return
	}

	var req struct {
		Config        store.StrategyConfig `json:"config" binding:"required"`
		PromptVariant string               `json:"prompt_variant"`
		AIModelID     string               `json:"ai_model_id"`
		RunRealAI     bool                 `json:"run_real_ai"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request parameters: " + err.Error()})
		return
	}

	if req.PromptVariant == "" {
		req.PromptVariant = "balanced"
	}

	// Create strategy engine to build prompt
	engine := decision.NewStrategyEngine(&req.Config)

	// Get candidate coins
	candidates, err := engine.GetCandidateCoins()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{
			"error":       "Failed to get candidate coins: " + err.Error(),
			"ai_response": "",
		})
		return
	}

	// Get timeframe configuration
	timeframes := req.Config.Indicators.Klines.SelectedTimeframes
	primaryTimeframe := req.Config.Indicators.Klines.PrimaryTimeframe
	klineCount := req.Config.Indicators.Klines.PrimaryCount

	// If no timeframes selected, use default values
	if len(timeframes) == 0 {
		// Backward compatibility: use primary and longer timeframes
		if primaryTimeframe != "" {
			timeframes = append(timeframes, primaryTimeframe)
		} else {
			timeframes = append(timeframes, "3m")
		}
		if req.Config.Indicators.Klines.LongerTimeframe != "" {
			timeframes = append(timeframes, req.Config.Indicators.Klines.LongerTimeframe)
		}
	}
	if primaryTimeframe == "" {
		primaryTimeframe = timeframes[0]
	}
	if klineCount <= 0 {
		klineCount = 30
	}

	fmt.Printf("📊 Using timeframes: %v, primary: %s, kline count: %d\n", timeframes, primaryTimeframe, klineCount)

	// Get real market data (using multiple timeframes)
	marketDataMap := make(map[string]*market.Data)
	for _, coin := range candidates {
		data, err := market.GetWithTimeframes(coin.Symbol, timeframes, primaryTimeframe, klineCount)
		if err != nil {
			// If getting data for a coin fails, log but continue
			fmt.Printf("⚠️  Failed to get market data for %s: %v\n", coin.Symbol, err)
			continue
		}
		marketDataMap[coin.Symbol] = data
	}

	// Build real context (for generating User Prompt)
	testContext := &decision.Context{
		CurrentTime:    time.Now().Format("2006-01-02 15:04:05"),
		RuntimeMinutes: 0,
		CallCount:      1,
		Account: decision.AccountInfo{
			TotalEquity:      1000.0,
			AvailableBalance: 1000.0,
			UnrealizedPnL:    0,
			TotalPnL:         0,
			TotalPnLPct:      0,
			MarginUsed:       0,
			MarginUsedPct:    0,
			PositionCount:    0,
		},
		Positions:      []decision.PositionInfo{},
		CandidateCoins: candidates,
		PromptVariant:  req.PromptVariant,
		MarketDataMap:  marketDataMap,
	}

	// Build System Prompt
	systemPrompt := engine.BuildSystemPrompt(1000.0, req.PromptVariant)

	// Build User Prompt (using real market data)
	userPrompt := engine.BuildUserPrompt(testContext)

	// If requesting real AI call
	if req.RunRealAI && req.AIModelID != "" {
		aiResponse, aiErr := s.runRealAITest(userID, req.AIModelID, systemPrompt, userPrompt)
		if aiErr != nil {
			c.JSON(http.StatusOK, gin.H{
				"system_prompt":   systemPrompt,
				"user_prompt":     userPrompt,
				"candidate_count": len(candidates),
				"candidates":      candidates,
				"prompt_variant":  req.PromptVariant,
				"ai_response":     fmt.Sprintf("❌ AI call failed: %s", aiErr.Error()),
				"ai_error":        aiErr.Error(),
				"note":            "AI call error",
			})
			return
		}

		c.JSON(http.StatusOK, gin.H{
			"system_prompt":   systemPrompt,
			"user_prompt":     userPrompt,
			"candidate_count": len(candidates),
			"candidates":      candidates,
			"prompt_variant":  req.PromptVariant,
			"ai_response":     aiResponse,
			"note":            "✅ Real AI test run successful",
		})
		return
	}

	// Return result (without actually calling AI, only return built prompt)
	c.JSON(http.StatusOK, gin.H{
		"system_prompt":   systemPrompt,
		"user_prompt":     userPrompt,
		"candidate_count": len(candidates),
		"candidates":      candidates,
		"prompt_variant":  req.PromptVariant,
		"ai_response":     "Please select an AI model and click 'Run Test' to perform real AI analysis.",
		"note":            "AI model not selected or real AI call not enabled",
	})
}

// runRealAITest Execute real AI test call
func (s *Server) runRealAITest(userID, modelID, systemPrompt, userPrompt string) (string, error) {
	// Get AI model configuration
	model, err := s.store.AIModel().Get(userID, modelID)
	if err != nil {
		return "", fmt.Errorf("failed to get AI model: %w", err)
	}

	if !model.Enabled {
		return "", fmt.Errorf("AI model %s is not enabled", model.Name)
	}

	if model.APIKey == "" {
		return "", fmt.Errorf("AI model %s is missing API Key", model.Name)
	}

	// Create AI client
	var aiClient mcp.AIClient
	provider := model.Provider

	switch provider {
	case "qwen":
		aiClient = mcp.NewQwenClient()
		aiClient.SetAPIKey(model.APIKey, model.CustomAPIURL, model.CustomModelName)
	case "deepseek":
		aiClient = mcp.NewDeepSeekClient()
		aiClient.SetAPIKey(model.APIKey, model.CustomAPIURL, model.CustomModelName)
	default:
		// Use generic client
		aiClient = mcp.NewClient()
		aiClient.SetAPIKey(model.APIKey, model.CustomAPIURL, model.CustomModelName)
	}

	// Call AI API
	response, err := aiClient.CallWithMessages(systemPrompt, userPrompt)
	if err != nil {
		return "", fmt.Errorf("AI API call failed: %w", err)
	}

	return response, nil
}