package main

import (
	"io"
	"net/http"
	"regexp"

	"git.1e99.eu/1e99/chitchat/server/storage"
)

func StoreHandler(store storage.Store, idRegex *regexp.Regexp, maxSize int) http.HandlerFunc {
	return func(res http.ResponseWriter, req *http.Request) {
		id := req.PathValue("id")

		matches := idRegex.MatchString(id)
		if !matches {
			res.WriteHeader(http.StatusBadRequest)
			return
		}

		switch req.Method {
		case http.MethodHead:
			err := store.Has(id)
			switch {
			case err == storage.ErrNotExists:
				res.WriteHeader(http.StatusNotFound)
				return
			case err != nil:
				res.WriteHeader(http.StatusInternalServerError)
				return
			}

			res.WriteHeader(http.StatusOK)
		case http.MethodGet:
			data, err := store.Get(id)
			switch {
			case err == storage.ErrNotExists:
				res.WriteHeader(http.StatusNotFound)
				return
			case err != nil:
				res.WriteHeader(http.StatusInternalServerError)
				return
			}

			res.WriteHeader(http.StatusOK)
			res.Write(data)
		case http.MethodPut:
			data, err := io.ReadAll(req.Body)
			if err != nil {
				res.WriteHeader(http.StatusBadGateway)
				return
			}

			if len(data) > maxSize {
				res.WriteHeader(http.StatusRequestEntityTooLarge)
				return
			}

			err = store.Put(id, data)
			switch {
			case err != nil:
				res.WriteHeader(http.StatusInternalServerError)
				return
			}

			res.WriteHeader(http.StatusNoContent)
		case http.MethodDelete:
			err := store.Delete(id)
			switch {
			case err == storage.ErrNotExists:
				res.WriteHeader(http.StatusNotFound)
				return
			case err != nil:
				res.WriteHeader(http.StatusInternalServerError)
				return
			}

			res.WriteHeader(http.StatusNoContent)
		default:
			res.WriteHeader(http.StatusMethodNotAllowed)
		}
	}
}