/*
Copyright 2015 The Kubernetes Authors.

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 portforward

import (
	"net"
	"os"
	"reflect"
	"strings"
	"testing"

	"k8s.io/apimachinery/pkg/util/httpstream"
)

type fakeDialer struct {
	dialed             bool
	conn               httpstream.Connection
	err                error
	negotiatedProtocol string
}

func (d *fakeDialer) Dial(protocols ...string) (httpstream.Connection, string, error) {
	d.dialed = true
	return d.conn, d.negotiatedProtocol, d.err
}

func TestParsePortsAndNew(t *testing.T) {
	tests := []struct {
		input            []string
		expected         []ForwardedPort
		expectParseError bool
		expectNewError   bool
	}{
		{input: []string{}, expectNewError: true},
		{input: []string{"a"}, expectParseError: true, expectNewError: true},
		{input: []string{":a"}, expectParseError: true, expectNewError: true},
		{input: []string{"-1"}, expectParseError: true, expectNewError: true},
		{input: []string{"65536"}, expectParseError: true, expectNewError: true},
		{input: []string{"0"}, expectParseError: true, expectNewError: true},
		{input: []string{"0:0"}, expectParseError: true, expectNewError: true},
		{input: []string{"a:5000"}, expectParseError: true, expectNewError: true},
		{input: []string{"5000:a"}, expectParseError: true, expectNewError: true},
		{
			input: []string{"5000", "5000:5000", "8888:5000", "5000:8888", ":5000", "0:5000"},
			expected: []ForwardedPort{
				{5000, 5000},
				{5000, 5000},
				{8888, 5000},
				{5000, 8888},
				{0, 5000},
				{0, 5000},
			},
		},
	}

	for i, test := range tests {
		parsed, err := parsePorts(test.input)
		haveError := err != nil
		if e, a := test.expectParseError, haveError; e != a {
			t.Fatalf("%d: parsePorts: error expected=%t, got %t: %s", i, e, a, err)
		}

		dialer := &fakeDialer{}
		expectedStopChan := make(chan struct{})
		readyChan := make(chan struct{})
		pf, err := New(dialer, test.input, expectedStopChan, readyChan, os.Stdout, os.Stderr)
		haveError = err != nil
		if e, a := test.expectNewError, haveError; e != a {
			t.Fatalf("%d: New: error expected=%t, got %t: %s", i, e, a, err)
		}

		if test.expectParseError || test.expectNewError {
			continue
		}

		for pi, expectedPort := range test.expected {
			if e, a := expectedPort.Local, parsed[pi].Local; e != a {
				t.Fatalf("%d: local expected: %d, got: %d", i, e, a)
			}
			if e, a := expectedPort.Remote, parsed[pi].Remote; e != a {
				t.Fatalf("%d: remote expected: %d, got: %d", i, e, a)
			}
		}

		if dialer.dialed {
			t.Fatalf("%d: expected not dialed", i)
		}
		if e, a := test.expected, pf.ports; !reflect.DeepEqual(e, a) {
			t.Fatalf("%d: ports: expected %#v, got %#v", i, e, a)
		}
		if e, a := expectedStopChan, pf.stopChan; e != a {
			t.Fatalf("%d: stopChan: expected %#v, got %#v", i, e, a)
		}
		if pf.Ready == nil {
			t.Fatalf("%d: Ready should be non-nil", i)
		}
	}
}

type GetListenerTestCase struct {
	Hostname                string
	Protocol                string
	ShouldRaiseError        bool
	ExpectedListenerAddress string
}

func TestGetListener(t *testing.T) {
	var pf PortForwarder
	testCases := []GetListenerTestCase{
		{
			Hostname:                "localhost",
			Protocol:                "tcp4",
			ShouldRaiseError:        false,
			ExpectedListenerAddress: "127.0.0.1",
		},
		{
			Hostname:                "127.0.0.1",
			Protocol:                "tcp4",
			ShouldRaiseError:        false,
			ExpectedListenerAddress: "127.0.0.1",
		},
		{
			Hostname:                "[::1]",
			Protocol:                "tcp6",
			ShouldRaiseError:        false,
			ExpectedListenerAddress: "::1",
		},
		{
			Hostname:         "[::1]",
			Protocol:         "tcp4",
			ShouldRaiseError: true,
		},
		{
			Hostname:         "127.0.0.1",
			Protocol:         "tcp6",
			ShouldRaiseError: true,
		},
		{
			// IPv6 address must be put into brackets. This test reveals this.
			Hostname:         "::1",
			Protocol:         "tcp6",
			ShouldRaiseError: true,
		},
	}

	for i, testCase := range testCases {
		expectedListenerPort := "12345"
		listener, err := pf.getListener(testCase.Protocol, testCase.Hostname, &ForwardedPort{12345, 12345})
		if err != nil && strings.Contains(err.Error(), "cannot assign requested address") {
			t.Logf("Can't test #%d: %v", i, err)
			continue
		}
		errorRaised := err != nil

		if testCase.ShouldRaiseError != errorRaised {
			t.Errorf("Test case #%d failed: Data %v an error has been raised(%t) where it should not (or reciprocally): %v", i, testCase, testCase.ShouldRaiseError, err)
			continue
		}
		if errorRaised {
			continue
		}

		if listener == nil {
			t.Errorf("Test case #%d did not raise an error but failed in initializing listener", i)
			continue
		}

		host, port, _ := net.SplitHostPort(listener.Addr().String())
		t.Logf("Asked a %s forward for: %s:%v, got listener %s:%s, expected: %s", testCase.Protocol, testCase.Hostname, 12345, host, port, expectedListenerPort)
		if host != testCase.ExpectedListenerAddress {
			t.Errorf("Test case #%d failed: Listener does not listen on exepected address: asked %v got %v", i, testCase.ExpectedListenerAddress, host)
		}
		if port != expectedListenerPort {
			t.Errorf("Test case #%d failed: Listener does not listen on exepected port: asked %v got %v", i, expectedListenerPort, port)

		}
		listener.Close()

	}
}
