package health

import (
	"net/http"
	_ "net/http/pprof" // Import for side effects (registers pprof handlers)

	"github.com/fraktal/mev-beta/internal/logger"
)

// PprofHandler provides production-safe pprof profiling endpoints
type PprofHandler struct {
	logger  *logger.Logger
	enabled bool
}

// NewPprofHandler creates a new pprof handler
func NewPprofHandler(logger *logger.Logger, enabled bool) *PprofHandler {
	return &PprofHandler{
		logger:  logger,
		enabled: enabled,
	}
}

// RegisterHTTPHandlers registers pprof handlers if enabled
func (p *PprofHandler) RegisterHTTPHandlers(mux *http.ServeMux) {
	if !p.enabled {
		p.logger.Info("🔒 pprof profiling endpoints disabled")
		return
	}

	// pprof handlers are automatically registered on DefaultServeMux
	// We need to proxy them to our custom mux
	mux.HandleFunc("/debug/pprof/", func(w http.ResponseWriter, r *http.Request) {
		http.DefaultServeMux.ServeHTTP(w, r)
	})
	mux.HandleFunc("/debug/pprof/cmdline", func(w http.ResponseWriter, r *http.Request) {
		http.DefaultServeMux.ServeHTTP(w, r)
	})
	mux.HandleFunc("/debug/pprof/profile", func(w http.ResponseWriter, r *http.Request) {
		http.DefaultServeMux.ServeHTTP(w, r)
	})
	mux.HandleFunc("/debug/pprof/symbol", func(w http.ResponseWriter, r *http.Request) {
		http.DefaultServeMux.ServeHTTP(w, r)
	})
	mux.HandleFunc("/debug/pprof/trace", func(w http.ResponseWriter, r *http.Request) {
		http.DefaultServeMux.ServeHTTP(w, r)
	})

	p.logger.Info("✅ pprof profiling endpoints enabled at /debug/pprof/")
	p.logger.Info("   Available endpoints:")
	p.logger.Info("   - /debug/pprof/          - Index of available profiles")
	p.logger.Info("   - /debug/pprof/heap      - Memory heap profile")
	p.logger.Info("   - /debug/pprof/goroutine - Goroutine profile")
	p.logger.Info("   - /debug/pprof/profile   - CPU profile (30s by default)")
	p.logger.Info("   - /debug/pprof/block     - Block profile")
	p.logger.Info("   - /debug/pprof/mutex     - Mutex profile")
	p.logger.Info("   - /debug/pprof/trace     - Execution trace")
	p.logger.Info("")
	p.logger.Info("   Usage examples:")
	p.logger.Info("   go tool pprof http://localhost:6060/debug/pprof/heap")
	p.logger.Info("   go tool pprof http://localhost:6060/debug/pprof/profile?seconds=30")
	p.logger.Info("   curl http://localhost:6060/debug/pprof/goroutine?debug=1")
}