package tubson

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"os/signal"
	"strings"
	"syscall"
)

type Http_method uint8; const (
	GET Http_method = iota
	POST
	PATCH
	PUT
	DELETE
)
func (method Http_method) to_string() string {
	switch method {
	case GET:
		return http.MethodGet
	case POST:
		return http.MethodPost
	case PATCH:
		return http.MethodPatch
	case PUT:
		return http.MethodPut
	case DELETE:
		return http.MethodDelete
	}

	return ""
}


type Http_status_code int; const (
	OK Http_status_code = http.StatusOK
	INTERNAL_SERVER_ERROR Http_status_code = http.StatusInternalServerError
	BAD_REQUEST Http_status_code = http.StatusBadRequest
)

type Empty_request_body struct {}
/* T Representing any request body struct
   S Representing any response body struct */
func New_endpoint[T any, S any](method Http_method, route string, endpoint string, handle_func func(body T, raw_request *http.Request) (S, Http_status_code)) {
	http.HandleFunc(method.to_string() + " /" + route + endpoint, func(response http.ResponseWriter, request *http.Request) {
		request_body_bytes, err := io.ReadAll(request.Body)
		if err != nil {
			response.WriteHeader(int(INTERNAL_SERVER_ERROR))
			log.Panicln(err)
			return
		}
		var decode_result T
		if len(request_body_bytes) != 0 {
			decoder := json.NewDecoder(strings.NewReader(string(request_body_bytes)))
			decoder.DisallowUnknownFields()
			err = decoder.Decode(&decode_result)
			if err != nil {
				response.WriteHeader(int(BAD_REQUEST))
				response.Write([]byte(err.Error()))
				log.Println(err)
				return
			}
		}

		body, status_code := handle_func(decode_result, request)
		encode_result, err := json.Marshal(body)
		if err != nil {
			response.WriteHeader(int(INTERNAL_SERVER_ERROR))
			log.Panicln(err)
			return
		}

		response.WriteHeader(int(status_code))
		response.Write(encode_result)
	})
}

func Start_server(http_server *http.Server, cleanup func()) {
	go func() {
		log.Fatal(http_server.ListenAndServe())
	}()
	fmt.Println("Timefu.li server started! Listening in on ", http_server.Addr)

	sigs := make(chan os.Signal, 1)
	signal.Notify(sigs, os.Interrupt, syscall.SIGTERM)
	<-sigs

	fmt.Println("Exit called, attempting to stop server!")
	ctx := context.Background()
	http_server.Shutdown(ctx)
	cleanup()
	os.Exit(1)
}