package main

import (
	"io"
	"net/http"

	"entanglement.garden/common/cloudinit"
	"github.com/sirupsen/logrus"
	"gopkg.in/yaml.v2"
)

var (
	httpStaticContent = map[string][]byte{}
)

func runHTTPServer(bind string) {
	logrus.WithField("bind", bind).Debug("starting temporary HTTP server")
	http.ListenAndServe(bind, httphandler{})
}

type httphandler struct{}

func (httphandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	log := logrus.WithFields(logrus.Fields{
		"method":      r.Method,
		"path":        r.URL,
		"remote_addr": r.RemoteAddr,
	})

	log.Debug("handling HTTP request")

	switch r.Method {
	case http.MethodGet:
		resp, ok := httpStaticContent[r.URL.Path]
		if !ok {
			w.WriteHeader(http.StatusNotFound)
			return
		}

		if resp == nil {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		_, err := w.Write(resp)
		if err != nil {
			log.WithError(err).Error("error serving HTTP response")
		}

	case http.MethodPost:
		printRequestBody(r)
		log.Info("VM booted")
		w.WriteHeader(http.StatusNoContent)
		wg.Done()

	default:
		w.WriteHeader(http.StatusNotFound)
		w.Write([]byte("not found"))
	}

}

func buildCloudConfig(base cloudinit.UserData, name string, phoneHomeURL string) error {
	userdata, err := yaml.Marshal(base)
	if err != nil {
		return err
	}
	httpStaticContent["/user-data"] = append([]byte("#cloud-config\n"), userdata...)

	metadata, err := yaml.Marshal(cloudinit.MetaData{
		InstanceID:    name,
		LocalHostname: name,
	})
	if err != nil {
		return err
	}
	httpStaticContent["/meta-data"] = metadata

	vendorData, err := yaml.Marshal(cloudinit.UserData{
		PhoneHome: cloudinit.PhoneHome{
			URL:  phoneHomeURL,
			Post: []string{"pub_key_dsa", "pub_key_rsa", "pub_key_ed25519", "fqdn"},
		},
	})
	if err != nil {
		return err
	}
	httpStaticContent["/vendor-data"] = vendorData

	return nil
}

func printRequestBody(r *http.Request) {
	log := logrus.WithFields(logrus.Fields{
		"method":      r.Method,
		"path":        r.URL,
		"remote_addr": r.RemoteAddr,
	})

	switch r.Header.Get("Content-Type") {
	case "application/x-www-form-urlencoded":
		if err := r.ParseForm(); err != nil {
			logrus.WithError(err).Error("error parsing request body")
			return
		}
		fields := logrus.Fields{}
		for k, v := range r.Form {
			if len(v) == 1 {
				fields[k] = v[0]
			} else {
				fields[k] = v
			}
		}
		log.WithFields(fields).Debug("form request body")
	default:
		body, err := io.ReadAll(r.Body)
		if err != nil {
			log.WithError(err).Error("error reading body")
		}
		r.Body.Close()

		log.Debug(string(body))
	}

}