package server

import (
	"context"
	"io/fs"
	"net/http"

	"github.com/mjensen/weimar/internal/config"
)

func New(cfg config.Config, webFS fs.FS) (*Server, error) {
	mux := http.NewServeMux()

	// API routes
	mux.HandleFunc("GET /api/health", handleHealth)

	// Auth
	mux.HandleFunc("POST /api/auth/login", handleNotImplemented)
	mux.HandleFunc("POST /api/auth/register", handleNotImplemented)

	// Images
	mux.HandleFunc("POST /api/upload", handleNotImplemented)
	mux.HandleFunc("GET /api/images", handleNotImplemented)
	mux.HandleFunc("GET /api/images/{id}", handleNotImplemented)
	mux.HandleFunc("GET /api/images/{id}/download", handleNotImplemented)
	mux.HandleFunc("GET /api/images/{id}/thumbnail", handleNotImplemented)

	// Tags
	mux.HandleFunc("GET /api/tags/suggest", handleNotImplemented)

	// SPA — serve index.html for all non-API, non-file routes
	spaFS := http.FileServer(http.FS(webFS))
	mux.Handle("/", spaFS)

	return &Server{
		cfg: cfg,
		mux: mux,
	}, nil
}

type Server struct {
	cfg config.Config
	mux *http.ServeMux
}

func (s *Server) Start(ctx context.Context) error {
	addr := s.cfg.Server.Host + ":" + itoa(s.cfg.Server.Port)
	srv := &http.Server{Addr: addr, Handler: s.mux}

	go func() {
		<-ctx.Done()
		srv.Shutdown(context.Background())
	}()

	return srv.ListenAndServe()
}

func itoa(n int) string {
	if n == 0 {
		return "0"
	}
	var buf [20]byte
	i := len(buf)
	for n > 0 {
		i--
		buf[i] = byte('0' + n%10)
		n /= 10
	}
	return string(buf[i:])
}

func handleHealth(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	w.Write([]byte(`{"status":"ok"}`))
}

func handleNotImplemented(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "not implemented", http.StatusNotImplemented)
}