package server

import (
	"context"
	"encoding/json"
	"log/slog"
	"net/http"
	"time"

	"git.daviestechlabs.io/daviestechlabs/ntfy-discord/internal/bridge"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)

// Server provides health and metrics endpoints
type Server struct {
	httpServer *http.Server
	bridge     *bridge.Bridge
}

// New creates a new HTTP server
func New(port string, b *bridge.Bridge) *Server {
	mux := http.NewServeMux()

	s := &Server{
		bridge: b,
		httpServer: &http.Server{
			Addr:         ":" + port,
			Handler:      mux,
			ReadTimeout:  5 * time.Second,
			WriteTimeout: 10 * time.Second,
		},
	}

	mux.HandleFunc("/health", s.handleHealth)
	mux.HandleFunc("/ready", s.handleReady)
	mux.Handle("/metrics", promhttp.Handler())

	return s
}

// Start begins serving HTTP requests
func (s *Server) Start() {
	slog.Info("starting HTTP server", "addr", s.httpServer.Addr)
	if err := s.httpServer.ListenAndServe(); err != http.ErrServerClosed {
		slog.Error("HTTP server error", "error", err)
	}
}

// Shutdown gracefully stops the server
func (s *Server) Shutdown(ctx context.Context) {
	ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
	defer cancel()

	if err := s.httpServer.Shutdown(ctx); err != nil {
		slog.Error("HTTP server shutdown error", "error", err)
	}
}

func (s *Server) handleHealth(w http.ResponseWriter, r *http.Request) {
	status := struct {
		Status  string `json:"status"`
		Healthy bool   `json:"healthy"`
	}{
		Status:  "ok",
		Healthy: s.bridge.IsHealthy(),
	}

	if !status.Healthy {
		status.Status = "unhealthy"
		w.WriteHeader(http.StatusServiceUnavailable)
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(status)
}

func (s *Server) handleReady(w http.ResponseWriter, r *http.Request) {
	status := struct {
		Status string `json:"status"`
		Ready  bool   `json:"ready"`
	}{
		Status: "ok",
		Ready:  s.bridge.IsReady(),
	}

	if !status.Ready {
		status.Status = "not ready"
		w.WriteHeader(http.StatusServiceUnavailable)
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(status)
}