// Copyright 2015 Light Code Labs, LLC
//
// 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 redirect

import (
	"bytes"
	"context"
	"crypto/tls"
	"io/ioutil"
	"log"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"github.com/caddyserver/caddy/caddyhttp/httpserver"
)

func TestRedirect(t *testing.T) {
	for i, test := range []struct {
		from             string
		expectedLocation string
		expectedCode     int
	}{
		{"http://localhost/from", "/to", http.StatusMovedPermanently},
		{"http://localhost/a", "/b", http.StatusTemporaryRedirect},
		{"http://localhost/aa", "", http.StatusOK},
		{"http://localhost/", "", http.StatusOK},
		{"http://localhost/a?foo=bar", "/b", http.StatusTemporaryRedirect},
		{"http://localhost/asdf?foo=bar", "", http.StatusOK},
		{"http://localhost/foo#bar", "", http.StatusOK},
		{"http://localhost/a#foo", "/b", http.StatusTemporaryRedirect},

		// The scheme checks that were added to this package don't actually
		// help with redirects because of Caddy's design: a redirect middleware
		// for http will always be different than the redirect middleware for
		// https because they have to be on different listeners. These tests
		// just go to show extra bulletproofing, I guess.
		{"http://localhost/scheme", "https://localhost/scheme", http.StatusMovedPermanently},
		{"https://localhost/scheme", "", http.StatusOK},
		{"https://localhost/scheme2", "http://localhost/scheme2", http.StatusMovedPermanently},
		{"http://localhost/scheme2", "", http.StatusOK},
		{"http://localhost/scheme3", "https://localhost/scheme3", http.StatusMovedPermanently},
		{"https://localhost/scheme3", "", http.StatusOK},
	} {
		var nextCalled bool

		re := Redirect{
			Next: httpserver.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
				nextCalled = true
				return 0, nil
			}),
			Rules: []Rule{
				{FromScheme: func() string { return "http" }, FromPath: "/from", To: "/to", Code: http.StatusMovedPermanently, RequestMatcher: httpserver.IfMatcher{}},
				{FromScheme: func() string { return "http" }, FromPath: "/a", To: "/b", Code: http.StatusTemporaryRedirect, RequestMatcher: httpserver.IfMatcher{}},

				// These http and https schemes would never actually be mixed in the same
				// redirect rule with Caddy because http and https schemes have different listeners,
				// so they don't share a redirect rule. So although these tests prove something
				// impossible with Caddy, it's extra bulletproofing at very little cost.
				{FromScheme: func() string { return "http" }, FromPath: "/scheme", To: "https://localhost/scheme", Code: http.StatusMovedPermanently, RequestMatcher: httpserver.IfMatcher{}},
				{FromScheme: func() string { return "https" }, FromPath: "/scheme2", To: "http://localhost/scheme2", Code: http.StatusMovedPermanently, RequestMatcher: httpserver.IfMatcher{}},
				{FromScheme: func() string { return "" }, FromPath: "/scheme3", To: "https://localhost/scheme3", Code: http.StatusMovedPermanently, RequestMatcher: httpserver.IfMatcher{}},
			},
		}

		req, err := http.NewRequest("GET", test.from, nil)
		if err != nil {
			t.Fatalf("Test %d: Could not create HTTP request: %v", i, err)
		}
		if strings.HasPrefix(test.from, "https://") {
			req.TLS = new(tls.ConnectionState) // faux HTTPS
		}

		rec := httptest.NewRecorder()
		if _, err := re.ServeHTTP(rec, req); err != nil {
			log.Println("[ERROR] failed to serve HTTP: ", err)
		}

		if rec.Header().Get("Location") != test.expectedLocation {
			t.Errorf("Test %d: Expected Location header to be %q but was %q",
				i, test.expectedLocation, rec.Header().Get("Location"))
		}

		if rec.Code != test.expectedCode {
			t.Errorf("Test %d: Expected status code to be %d but was %d",
				i, test.expectedCode, rec.Code)
		}

		if nextCalled && test.expectedLocation != "" {
			t.Errorf("Test %d: Next handler was unexpectedly called", i)
		}
	}
}

func TestParametersRedirect(t *testing.T) {
	re := Redirect{
		Rules: []Rule{
			{FromScheme: func() string { return "http" }, FromPath: "/", Meta: false, To: "http://example.com{uri}", RequestMatcher: httpserver.IfMatcher{}},
		},
	}

	req, err := http.NewRequest("GET", "/a?b=c", nil)
	if err != nil {
		t.Fatalf("Test 1: Could not create HTTP request: %v", err)
	}
	ctx := context.WithValue(req.Context(), httpserver.OriginalURLCtxKey, *req.URL)
	req = req.WithContext(ctx)

	rec := httptest.NewRecorder()
	if _, err := re.ServeHTTP(rec, req); err != nil {
		log.Println("[ERROR] failed to serve HTTP: ", err)
	}

	if got, want := rec.Header().Get("Location"), "http://example.com/a?b=c"; got != want {
		t.Fatalf("Test 1: expected location header %s but was %s", want, got)
	}

	re = Redirect{
		Rules: []Rule{
			{FromScheme: func() string { return "http" }, FromPath: "/", Meta: false, To: "http://example.com/a{path}?b=c&{query}", RequestMatcher: httpserver.IfMatcher{}},
		},
	}

	req, err = http.NewRequest("GET", "/d?e=f", nil)
	if err != nil {
		t.Fatalf("Test 2: Could not create HTTP request: %v", err)
	}
	ctx = context.WithValue(req.Context(), httpserver.OriginalURLCtxKey, *req.URL)
	req = req.WithContext(ctx)

	if _, err := re.ServeHTTP(rec, req); err != nil {
		log.Println("[ERROR] failed to serve HTTP: ", err)
	}

	if got, want := rec.Header().Get("Location"), "http://example.com/a/d?b=c&e=f"; got != want {
		t.Fatalf("Test 2: expected location header %s but was %s", want, got)
	}
}

func TestMetaRedirect(t *testing.T) {
	re := Redirect{
		Rules: []Rule{
			{FromScheme: func() string { return "http" }, FromPath: "/whatever", Meta: true, To: "/something", RequestMatcher: httpserver.IfMatcher{}},
			{FromScheme: func() string { return "http" }, FromPath: "/", Meta: true, To: "https://example.com/", RequestMatcher: httpserver.IfMatcher{}},
		},
	}

	for i, test := range re.Rules {
		req, err := http.NewRequest("GET", test.FromPath, nil)
		if err != nil {
			t.Fatalf("Test %d: Could not create HTTP request: %v", i, err)
		}

		rec := httptest.NewRecorder()
		if _, err := re.ServeHTTP(rec, req); err != nil {
			log.Println("[ERROR] failed to serve HTTP: ", err)
		}

		body, err := ioutil.ReadAll(rec.Body)
		if err != nil {
			t.Fatalf("Test %d: Could not read HTTP response body: %v", i, err)
		}
		expectedSnippet := `<meta http-equiv="refresh" content="0; URL='` + test.To + `'">`
		if !bytes.Contains(body, []byte(expectedSnippet)) {
			t.Errorf("Test %d: Expected Response Body to contain %q but was %q",
				i, expectedSnippet, body)
		}
	}
}
