package main

import (
	"context"
	"crypto/tls"
	"database/sql"
	"encoding/json"
	"net/http"
	"time"

	"tailscale.com/client/tailscale"
	"tailscale.com/tsnet"
	"within.website/ln"
	"within.website/ln/ex"
)

type Server struct {
	db  *sql.DB
	mux *http.ServeMux
	srv *tsnet.Server
}

func NewServer(db *sql.DB, srv *tsnet.Server) *Server {
	mux := http.NewServeMux()

	s := &Server{
		db:  db,
		mux: mux,
		srv: srv,
	}

	mux.HandleFunc("/api/whois", s.whois)

	return s
}

func (s *Server) ListenAndServe() error {
	l, err := s.srv.Listen("tcp", ":443")
	if err != nil {
		return err
	}

	l = tls.NewListener(l, &tls.Config{
		GetCertificate: func(chi *tls.ClientHelloInfo) (*tls.Certificate, error) {
			c, err := tailscale.GetCertificate(chi)
			if err != nil {
				ln.Error(context.Background(), err, ln.F{"remote_addr": chi.Conn.RemoteAddr().String()})
			}
			return c, err
		},
	})

	hs := &http.Server{
		IdleTimeout: 5 * time.Minute,
		Handler:     ex.HTTPLog(s),
	}

	ln.Log(context.Background(), ln.Info("listening on https://twitchalitics.shark-harmonic.ts.net"))

	return hs.Serve(l)
}

func (s Server) whois(w http.ResponseWriter, r *http.Request) {
	userInfo, err := tailscale.WhoIs(r.Context(), r.RemoteAddr)
	if err != nil {
		http.Error(w, "can't get whois response: "+err.Error(), http.StatusInternalServerError)
		ln.Error(r.Context(), err)
		return
	}

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

func (s Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	userInfo, err := tailscale.WhoIs(r.Context(), r.RemoteAddr)
	if err != nil {
		http.Error(w, "can't get whois response: "+err.Error(), http.StatusInternalServerError)
		ln.Error(r.Context(), err)
		return
	}

	ctx := ln.WithF(r.Context(), ln.F{"username": userInfo.UserProfile.LoginName, "hostname": userInfo.Node.ComputedName, "os": userInfo.Node.Hostinfo.OS})
	r = r.WithContext(ctx)

	s.mux.ServeHTTP(w, r)
}