// +build go1.7

package httprouter

import (

	"context"

	"net/http"

)

type paramsKey struct{}

// ParamsKey is the request context key under which URL params are stored.

//

// This is only present from go 1.7.

var ParamsKey = paramsKey{}

// Handler is an adapter which allows the usage of an http.Handler as a

// request handle. With go 1.7+, the Params will be available in the

// request context under ParamsKey.

func (r *Router) Handler(method, path string, handler http.Handler) {

	r.Handle(method, path,

		func(w http.ResponseWriter, req *http.Request, p Params) {

			ctx := req.Context()

			ctx = context.WithValue(ctx, ParamsKey, p)

			req = req.WithContext(ctx)

			handler.ServeHTTP(w, req)

		},

	)

}

// ParamsFromContext pulls the URL parameters from a request context,

// or returns nil if none are present.

//

// This is only present from go 1.7.

func ParamsFromContext(ctx context.Context) Params {

	p, _ := ctx.Value(ParamsKey).(Params)

	return p

}