// Copyright 2018 Drone.IO Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package httputil

import (
	"math"
	"net/http"
	"strings"
)

// IsHTTPS is a helper function that evaluates the http.Request
// and returns True if the Request uses HTTPS. It is able to detect,
// using the X-Forwarded-Proto, if the original request was HTTPS and
// routed through a reverse proxy with SSL termination.
func IsHTTPS(r *http.Request) bool {
	switch {
	case r.URL.Scheme == "https":
		return true
	case r.TLS != nil:
		return true
	case strings.HasPrefix(r.Proto, "HTTPS"):
		return true
	case r.Header.Get("X-Forwarded-Proto") == "https":
		return true
	default:
		return false
	}
}

// SetCookie writes the cookie value.
func SetCookie(w http.ResponseWriter, r *http.Request, name, value string) {
	cookie := http.Cookie{
		Name:     name,
		Value:    value,
		Path:     "/",
		Domain:   r.URL.Host,
		HttpOnly: true,
		Secure:   IsHTTPS(r),
		MaxAge:   math.MaxInt32, // the cookie value (token) is responsible for expiration
	}

	http.SetCookie(w, &cookie)
}

// DelCookie deletes a cookie.
func DelCookie(w http.ResponseWriter, r *http.Request, name string) {
	cookie := http.Cookie{
		Name:   name,
		Value:  "deleted",
		Path:   "/",
		Domain: r.URL.Host,
		MaxAge: -1,
	}

	http.SetCookie(w, &cookie)
}