package metrics

import (
	"context"
	"sync"

	"go.uber.org/zap"

	"tyapi-server/internal/shared/interfaces"
)

// BusinessMetrics 业务指标收集器
type BusinessMetrics struct {
	metrics interfaces.MetricsCollector
	logger  *zap.Logger
	mutex   sync.RWMutex

	// 业务指标缓存
	userMetrics  map[string]int64
	orderMetrics map[string]int64
}

// NewBusinessMetrics 创建业务指标收集器
func NewBusinessMetrics(metrics interfaces.MetricsCollector, logger *zap.Logger) *BusinessMetrics {
	bm := &BusinessMetrics{
		metrics:      metrics,
		logger:       logger,
		userMetrics:  make(map[string]int64),
		orderMetrics: make(map[string]int64),
	}

	// 注册业务指标
	bm.registerBusinessMetrics()

	return bm
}

// registerBusinessMetrics 注册业务指标
func (bm *BusinessMetrics) registerBusinessMetrics() {
	// 用户相关指标
	bm.metrics.RegisterCounter("users_created_total", "Total number of users created", []string{"source"})
	bm.metrics.RegisterCounter("users_login_total", "Total number of user logins", []string{"method", "status"})
	bm.metrics.RegisterGauge("users_active_sessions", "Current number of active user sessions", nil)

	// 订单相关指标
	bm.metrics.RegisterCounter("orders_created_total", "Total number of orders created", []string{"status"})
	bm.metrics.RegisterCounter("orders_amount_total", "Total order amount in cents", []string{"currency"})
	bm.metrics.RegisterHistogram("orders_processing_duration_seconds", "Order processing duration", []string{"status"}, []float64{0.1, 0.5, 1, 2, 5, 10, 30})

	// API相关指标
	bm.metrics.RegisterCounter("api_errors_total", "Total number of API errors", []string{"endpoint", "error_type"})
	bm.metrics.RegisterHistogram("api_response_size_bytes", "API response size in bytes", []string{"endpoint"}, []float64{100, 1000, 10000, 100000})

	// 缓存相关指标
	bm.metrics.RegisterCounter("cache_operations_total", "Total number of cache operations", []string{"operation", "result"})
	bm.metrics.RegisterGauge("cache_memory_usage_bytes", "Cache memory usage in bytes", []string{"cache_type"})

	// 数据库相关指标
	bm.metrics.RegisterHistogram("database_query_duration_seconds", "Database query duration", []string{"operation", "table"}, []float64{0.001, 0.01, 0.1, 1, 10})
	bm.metrics.RegisterCounter("database_errors_total", "Total number of database errors", []string{"operation", "error_type"})

	bm.logger.Info("Business metrics registered successfully")
}

// User相关指标

// RecordUserCreated 记录用户创建
func (bm *BusinessMetrics) RecordUserCreated(source string) {
	bm.metrics.IncrementCounter("users_created_total", map[string]string{
		"source": source,
	})

	bm.mutex.Lock()
	bm.userMetrics["created"]++
	bm.mutex.Unlock()

	bm.logger.Debug("Recorded user created", zap.String("source", source))
}

// RecordUserLogin 记录用户登录
func (bm *BusinessMetrics) RecordUserLogin(method, status string) {
	bm.metrics.IncrementCounter("users_login_total", map[string]string{
		"method": method,
		"status": status,
	})

	bm.logger.Debug("Recorded user login", zap.String("method", method), zap.String("status", status))
}

// UpdateActiveUserSessions 更新活跃用户会话数
func (bm *BusinessMetrics) UpdateActiveUserSessions(count float64) {
	bm.metrics.RecordGauge("users_active_sessions", count, nil)
}

// Order相关指标

// RecordOrderCreated 记录订单创建
func (bm *BusinessMetrics) RecordOrderCreated(status string, amount float64, currency string) {
	bm.metrics.IncrementCounter("orders_created_total", map[string]string{
		"status": status,
	})

	// 记录订单金额（以分为单位）
	amountCents := int64(amount * 100)
	bm.metrics.IncrementCounter("orders_amount_total", map[string]string{
		"currency": currency,
	})

	bm.mutex.Lock()
	bm.orderMetrics["created"]++
	bm.orderMetrics["amount"] += amountCents
	bm.mutex.Unlock()

	bm.logger.Debug("Recorded order created",
		zap.String("status", status),
		zap.Float64("amount", amount),
		zap.String("currency", currency))
}

// RecordOrderProcessingDuration 记录订单处理时长
func (bm *BusinessMetrics) RecordOrderProcessingDuration(status string, duration float64) {
	bm.metrics.RecordHistogram("orders_processing_duration_seconds", duration, map[string]string{
		"status": status,
	})
}

// API相关指标

// RecordAPIError 记录API错误
func (bm *BusinessMetrics) RecordAPIError(endpoint, errorType string) {
	bm.metrics.IncrementCounter("api_errors_total", map[string]string{
		"endpoint":   endpoint,
		"error_type": errorType,
	})

	bm.logger.Debug("Recorded API error",
		zap.String("endpoint", endpoint),
		zap.String("error_type", errorType))
}

// RecordAPIResponseSize 记录API响应大小
func (bm *BusinessMetrics) RecordAPIResponseSize(endpoint string, sizeBytes float64) {
	bm.metrics.RecordHistogram("api_response_size_bytes", sizeBytes, map[string]string{
		"endpoint": endpoint,
	})
}

// Cache相关指标

// RecordCacheOperation 记录缓存操作
func (bm *BusinessMetrics) RecordCacheOperation(operation, result string) {
	bm.metrics.IncrementCounter("cache_operations_total", map[string]string{
		"operation": operation,
		"result":    result,
	})
}

// UpdateCacheMemoryUsage 更新缓存内存使用量
func (bm *BusinessMetrics) UpdateCacheMemoryUsage(cacheType string, usageBytes float64) {
	bm.metrics.RecordGauge("cache_memory_usage_bytes", usageBytes, map[string]string{
		"cache_type": cacheType,
	})
}

// Database相关指标

// RecordDatabaseQuery 记录数据库查询
func (bm *BusinessMetrics) RecordDatabaseQuery(operation, table string, duration float64) {
	bm.metrics.RecordHistogram("database_query_duration_seconds", duration, map[string]string{
		"operation": operation,
		"table":     table,
	})
}

// RecordDatabaseError 记录数据库错误
func (bm *BusinessMetrics) RecordDatabaseError(operation, errorType string) {
	bm.metrics.IncrementCounter("database_errors_total", map[string]string{
		"operation":  operation,
		"error_type": errorType,
	})

	bm.logger.Debug("Recorded database error",
		zap.String("operation", operation),
		zap.String("error_type", errorType))
}

// 获取统计信息

// GetUserStats 获取用户统计
func (bm *BusinessMetrics) GetUserStats() map[string]int64 {
	bm.mutex.RLock()
	defer bm.mutex.RUnlock()

	stats := make(map[string]int64)
	for k, v := range bm.userMetrics {
		stats[k] = v
	}
	return stats
}

// GetOrderStats 获取订单统计
func (bm *BusinessMetrics) GetOrderStats() map[string]int64 {
	bm.mutex.RLock()
	defer bm.mutex.RUnlock()

	stats := make(map[string]int64)
	for k, v := range bm.orderMetrics {
		stats[k] = v
	}
	return stats
}

// GetOverallStats 获取整体统计
func (bm *BusinessMetrics) GetOverallStats() map[string]interface{} {
	return map[string]interface{}{
		"user_stats":  bm.GetUserStats(),
		"order_stats": bm.GetOrderStats(),
	}
}

// Reset 重置统计数据
func (bm *BusinessMetrics) Reset() {
	bm.mutex.Lock()
	defer bm.mutex.Unlock()

	bm.userMetrics = make(map[string]int64)
	bm.orderMetrics = make(map[string]int64)

	bm.logger.Info("Business metrics reset")
}

// Context相关方法

// WithContext 创建带上下文的业务指标收集器
func (bm *BusinessMetrics) WithContext(ctx context.Context) *BusinessMetrics {
	// 这里可以从context中提取追踪信息，关联指标
	return bm
}

// 实现Service接口（如果需要）

// Name 返回服务名称
func (bm *BusinessMetrics) Name() string {
	return "business-metrics"
}

// Initialize 初始化服务
func (bm *BusinessMetrics) Initialize(ctx context.Context) error {
	bm.logger.Info("Business metrics service initialized")
	return nil
}

// HealthCheck 健康检查
func (bm *BusinessMetrics) HealthCheck(ctx context.Context) error {
	// 检查指标收集器是否正常
	return nil
}

// Shutdown 关闭服务
func (bm *BusinessMetrics) Shutdown(ctx context.Context) error {
	bm.logger.Info("Business metrics service shutdown")
	return nil
}