package service

import (
	"io/ioutil"
	"log"
	"net/http"
	"strings"
)

type Status int

const (
	OK Status = iota
	WAITING
	ERROR
)

type HttpServer struct {
	manager *Manager
	status  Status
}

type CreateCSRRequest struct {
	*BaseMessage
	Hostname string
}

type CreateCSRResponse struct {
	*BaseMessage
	CSR string `json:"csr"`
}

type UpdateOpenVPNConfigRequest struct {
	*BaseMessage
	Config string
}

type DeliverCertificateRequest struct {
	*BaseMessage
	Certificate string
}

func NewHttpServer(manager *Manager) *HttpServer {
	return &HttpServer{manager, WAITING}
}

func (it *HttpServer) Start() {
	http.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
		log.Printf("%s /", strings.ToUpper(request.Method))
		writer.WriteHeader(200)
		writer.Write([]byte("Don't"))
	})

	http.HandleFunc("/create-csr", func(writer http.ResponseWriter, request *http.Request) {
		log.Printf("%s /create-csr", strings.ToUpper(request.Method))
		req := &CreateCSRRequest{}
		err := it.verifyRequest(request, req)

		if err != nil {
			log.Printf("Error on %s %s: %s", request.Method, request.URL.Path, err)
			writer.WriteHeader(400)
			return
		}

		csr, err := it.manager.CreateCSR(req.Hostname)
		if err != nil {
			writer.WriteHeader(500)
			return
		}

		it.writeResponse(writer, CreateCSRResponse{
			CSR: string(csr),
		})
	})

	http.HandleFunc("/deliver-crt", func(writer http.ResponseWriter, request *http.Request) {
		log.Printf("%s /deliver-crt", strings.ToUpper(request.Method))
		req := &DeliverCertificateRequest{}
		err := it.verifyRequest(request, req)
		if err != nil {
			log.Printf("Error on %s %s: %s", request.Method, request.URL.Path, err)
			writer.WriteHeader(400)
			return
		}

		err = it.manager.UpdateCertificate(req.Certificate)
		if err != nil {
			writer.WriteHeader(500)
			return
		}

		it.manager.openVPN.Start()
	})

	http.HandleFunc("/update-openvpn-config", func(writer http.ResponseWriter, request *http.Request) {
		log.Printf("%s /update-openvpn-config", strings.ToUpper(request.Method))
		req := &UpdateOpenVPNConfigRequest{}
		err := it.verifyRequest(request, req)
		if err != nil {
			log.Printf("Error on %s %s: %s", request.Method, request.URL.Path, err)
			writer.WriteHeader(400)
			return
		}

		err = it.manager.openVPN.UpdateConfig(req.Config)
		if err != nil {
			writer.WriteHeader(500)
			return
		}

		it.manager.openVPN.Restart()
	})

	http.ListenAndServe(":7864", nil)
}

func (it *HttpServer) writeResponse(writer http.ResponseWriter, v interface{}) error {
	return EncryptAndSign(v, it.manager.privateKey, it.manager.CAPublicKey(), it.manager.GetServerFingerprint(), writer)
}

func (it *HttpServer) verifyRequest(r *http.Request, v interface{}) (error) {
	hexBody, err := ioutil.ReadAll(r.Body)
	if err != nil {
		return err
	}

	return DecryptAndVerify(hexBody, it.manager.privateKey, it.manager.CAPublicKey(), it.manager.GetServerFingerprint(), v)
}