package observability

import (
	"sync/atomic"
	"time"
)

// Metrics collects system metrics
type Metrics struct {
	SessionCreations    int64
	ActiveSessions      int64
	MessagesProcessed   int64
	ASRLatency          int64 // microseconds
	TTSLatency          int64 // microseconds
	LLMLatency          int64 // microseconds
	Errors              int64
}

var globalMetrics = &Metrics{}

// GetMetrics returns current metrics
func GetMetrics() *Metrics {
	return &Metrics{
		SessionCreations:  atomic.LoadInt64(&globalMetrics.SessionCreations),
		ActiveSessions:    atomic.LoadInt64(&globalMetrics.ActiveSessions),
		MessagesProcessed: atomic.LoadInt64(&globalMetrics.MessagesProcessed),
		ASRLatency:        atomic.LoadInt64(&globalMetrics.ASRLatency),
		TTSLatency:        atomic.LoadInt64(&globalMetrics.TTSLatency),
		LLMLatency:        atomic.LoadInt64(&globalMetrics.LLMLatency),
		Errors:            atomic.LoadInt64(&globalMetrics.Errors),
	}
}

// IncrementSessionCreations increments session creation count
func IncrementSessionCreations() {
	atomic.AddInt64(&globalMetrics.SessionCreations, 1)
}

// IncrementActiveSessions increments active session count
func IncrementActiveSessions() {
	atomic.AddInt64(&globalMetrics.ActiveSessions, 1)
}

// DecrementActiveSessions decrements active session count
func DecrementActiveSessions() {
	atomic.AddInt64(&globalMetrics.ActiveSessions, -1)
}

// IncrementMessagesProcessed increments message count
func IncrementMessagesProcessed() {
	atomic.AddInt64(&globalMetrics.MessagesProcessed, 1)
}

// RecordASRLatency records ASR latency
func RecordASRLatency(duration time.Duration) {
	atomic.StoreInt64(&globalMetrics.ASRLatency, duration.Microseconds())
}

// RecordTTSLatency records TTS latency
func RecordTTSLatency(duration time.Duration) {
	atomic.StoreInt64(&globalMetrics.TTSLatency, duration.Microseconds())
}

// RecordLLMLatency records LLM latency
func RecordLLMLatency(duration time.Duration) {
	atomic.StoreInt64(&globalMetrics.LLMLatency, duration.Microseconds())
}

// IncrementErrors increments error count
func IncrementErrors() {
	atomic.AddInt64(&globalMetrics.Errors, 1)
}