package v2

import (
	"sync"

	"github.com/gorilla/mux"
)

// The following are definitions of the name under which all V2 routes are
// registered. These symbols can be used to look up a route based on the name.
const (
	RouteNameBase            = "base"
	RouteNameManifest        = "manifest"
	RouteNameTags            = "tags"
	RouteNameBlob            = "blob"
	RouteNameBlobUpload      = "blob-upload"
	RouteNameBlobUploadChunk = "blob-upload-chunk"
	RouteNameCatalog         = "catalog"
)

var (
	baseRouter           *mux.Router
	createBaseRouterOnce sync.Once
)

// Router builds a gorilla router with named routes for the various API
// methods. This can be used directly by both server implementations and
// clients.
func Router() *mux.Router {
	createBaseRouterOnce.Do(func() {
		baseRouter = RouterWithPrefix("")
	})
	return baseRouter
}

// RouterWithPrefix builds a gorilla router with a configured prefix
// on all routes.
func RouterWithPrefix(prefix string) *mux.Router {
	rootRouter := mux.NewRouter()
	router := rootRouter
	if prefix != "" {
		router = router.PathPrefix(prefix).Subrouter()
	}

	router.StrictSlash(true)

	for _, descriptor := range routeDescriptors {
		router.Path(descriptor.Path).Name(descriptor.Name)
	}

	return rootRouter
}