package middleware

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

	"git.red-panda.pet/pandaware/house/backend/router"
)

func ParseJSONBody[T any](ctx *router.Context) error {
	contentType := ctx.Request.Header.Get("Content-Type")
	if contentType != "application/json" {
		return ctx.GenericError(nil, http.StatusBadRequest)
	}

	var body T

	dec := json.NewDecoder(ctx.Request.Body)
	err := dec.Decode(&body)
	if err != nil {
		return ctx.GenericError(err, http.StatusBadRequest)
	}

	ctx.With(jsonBodyKey, body)

	return nil
}

func ParseJSONBodyWithValidator[T any](
	ctx *router.Context,
	r router.ValidatedBodyRoute,
	validator func(value T) error,
) error {
	err := ParseJSONBody[T](ctx)
	if err != nil {
		return err
	}
	body := JSONBody[T](r, ctx)
	return validator(body)
}

func JSONBody[T any](r router.ValidatedBodyRoute, ctx *router.Context) T {
	body, ok := ctx.Value(jsonBodyKey).(T)
	if !ok {
		panic(errors.New("middleware.JSONBody cannot be used with a route that doesn't implement router.ValidatedBodyRoute"))
	}
	return body
}