package metrics

import (
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promauto"
)

var (
	// HTTP requests
	HTTPRequestsTotal = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Name: "http_requests_total",
			Help: "Total number of HTTP requests",
		},
		[]string{"method", "path", "status"},
	)

	HTTPRequestDuration = promauto.NewHistogramVec(
		prometheus.HistogramOpts{
			Name:    "http_request_duration_seconds",
			Help:    "HTTP request latency in seconds",
			Buckets: []float64{0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2.5, 5, 10},
		},
		[]string{"method", "path"},
	)

	// AI / LLM tokens
	LLMTokensTotal = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Name: "ai_tokens_total",
			Help: "Total number of AI tokens consumed",
		},
		[]string{"model", "type"}, // type: prompt | completion
	)

	LLMRequestsTotal = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Name: "ai_requests_total",
			Help: "Total number of AI/LLM API requests",
		},
		[]string{"model", "status"},
	)

	LLMRequestDuration = promauto.NewHistogramVec(
		prometheus.HistogramOpts{
			Name:    "ai_request_duration_seconds",
			Help:    "AI/LLM API request latency in seconds",
			Buckets: []float64{0.1, 0.5, 1, 2, 5, 10, 30, 60},
		},
		[]string{"model"},
	)

	// Chat / conversation
	ConversationsTotal = promauto.NewCounter(
		prometheus.CounterOpts{
			Name: "conversations_total",
			Help: "Total number of chat conversations created",
		},
	)

	MessagesTotal = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Name: "messages_total",
			Help: "Total number of chat messages",
		},
		[]string{"role"}, // role: user | assistant
	)

	// Auth
	AuthFailuresTotal = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Name: "auth_failures_total",
			Help: "Total number of authentication failures",
		},
		[]string{"reason"},
	)
)