package httpx

import (
	"encoding/json"
	"errors"
	"net/http"
)

type statusError struct {
	status int
	err    error
}

func (e statusError) Error() string {
	if e.err == nil {
		return ""
	}
	return e.err.Error()
}

func (e statusError) Unwrap() error {
	return e.err
}

func ErrorWithStatus(status int, err error) error {
	if err == nil {
		return nil
	}
	return statusError{status: status, err: err}
}

func StatusFromError(err error) (int, bool) {
	var target statusError
	if errors.As(err, &target) {
		return target.status, true
	}
	return 0, false
}

func WriteJSON(w http.ResponseWriter, status int, v any) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(status)
	enc := json.NewEncoder(w)
	enc.SetIndent("", "  ")
	_ = enc.Encode(v)
}

func WriteError(w http.ResponseWriter, status int, msg string) {
	WriteJSON(w, status, map[string]string{"error": msg})
}

func DecodeJSON(r *http.Request, dst any) error {
	dec := json.NewDecoder(r.Body)
	dec.DisallowUnknownFields()
	return dec.Decode(dst)
}

func CORSMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Access-Control-Allow-Origin", "*")
		w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, PATCH, DELETE, OPTIONS")
		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
		if r.Method == http.MethodOptions {
			w.WriteHeader(http.StatusNoContent)
			return
		}
		next.ServeHTTP(w, r)
	})
}