package router

import (
	"errors"
	"net/http"
)

type Router struct {
	t        *tree
	NotFound http.HandlerFunc
}

func New() *Router {
	return &Router{
		t:        newTree(),
		NotFound: http.NotFound,
	}
}

func (rt *Router) Add(path string, foo http.HandlerFunc) error {
	return rt.t.Insert(path, foo)
}

func (rt *Router) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	foo := rt.t.Lookup(r.URL.Path)
	if foo == nil {
		rt.NotFound(w, r)
		return
	}
	foo(w, r)
}

func Params(r *http.Request, toSet ...*string) error {
	params := r.Header[WildcardHeader]
	if len(params) != len(toSet) {
		return errors.New("missing params")
	}
	for i := range params {
		if len(params[i]) < 1 {
			return errors.New("empty params")
		}
		if toSet[i] == nil {
			return errors.New("cannot set nil param")
		}
		*toSet[i] = params[i]
	}
	return nil
}