package nex

import (
	"bytes"
	"context"
	"crypto/tls"
	"fmt"
	"io"
	"net"

	"tildegit.org/tjp/sliderule/internal"
	"tildegit.org/tjp/sliderule/internal/types"
	"tildegit.org/tjp/sliderule/logging"
)

type nexServer struct {
	internal.Server
	handler types.Handler
}

func (ns nexServer) Protocol() string { return "NEX" }

// NewServer builds a new nex server
func NewServer(
	ctx context.Context,
	hostname string,
	network string,
	address string,
	handler types.Handler,
	baseLog logging.Logger,
) (types.Server, error) {
	ns := &nexServer{handler: handler}

	hostname = internal.JoinDefaultPort(hostname, "1900")
	address = internal.JoinDefaultPort(address, "1900")

	var err error
	ns.Server, err = internal.NewServer(ctx, hostname, network, address, baseLog, ns.handleConn)
	if err != nil {
		return nil, err
	}

	return ns, err
}

func NewTLSServer(
	ctx context.Context,
	hostname string,
	network string,
	address string,
	handler types.Handler,
	baseLog logging.Logger,
	tlsConfig *tls.Config,
) (types.Server, error) {
	ns, err := NewServer(ctx, hostname, network, address, handler, baseLog)
	if err != nil {
		return nil, err
	}

	ns.(*nexServer).Listener = tls.NewListener(ns.(*nexServer).Listener, tlsConfig)
	return ns, nil
}

func (ns *nexServer) handleConn(conn net.Conn) {
	request, err := ParseRequest(conn)
	if err != nil {
		_, _ = fmt.Fprint(conn, err.Error()+"\n")
	}

	request.Server = ns
	request.RemoteAddr = conn.RemoteAddr()

	if tlsconn, ok := conn.(*tls.Conn); ok {
		state := tlsconn.ConnectionState()
		request.TLSState = &state
	}

	defer func() {
		if r := recover(); r != nil {
			_ = ns.LogError("msg", "panic in handler", "err", r)
			_, _ = fmt.Fprint(conn, "Error handling request.\n")
		}
	}()
	response := ns.handler.Handle(ns.Ctx, request)
	if response == nil {
		response = Response(bytes.NewBufferString("Document not found."))
	}

	defer response.Close()
	_, _ = io.Copy(conn, response.Body)
}