// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause

//go:build !plan9

package sessionrecording

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/netip"
	"net/url"
	"testing"
	"time"

	"go.uber.org/zap"
	"tailscale.com/client/tailscale/apitype"
	"tailscale.com/k8s-operator/sessionrecording/fakes"
	"tailscale.com/sessionrecording"
	"tailscale.com/tailcfg"
	"tailscale.com/tsnet"
	"tailscale.com/tstest"
)

func Test_Hijacker(t *testing.T) {
	zl, err := zap.NewDevelopment()
	if err != nil {
		t.Fatal(err)
	}
	tests := []struct {
		name                        string
		failOpen                    bool
		failRecorderConnect         bool // fail initial connect to the recorder
		failRecorderConnPostConnect bool // send error down the error channel
		wantsConnClosed             bool
		wantsSetupErr               bool
		proto                       Protocol
	}{
		{
			name:  "setup_succeeds_conn_stays_open",
			proto: SPDYProtocol,
		},
		{
			name:  "setup_succeeds_conn_stays_open_ws",
			proto: WSProtocol,
		},
		{
			name:                "setup_fails_policy_is_to_fail_open_conn_stays_open",
			failOpen:            true,
			failRecorderConnect: true,
			proto:               SPDYProtocol,
		},
		{
			name:                "setup_fails_policy_is_to_fail_closed_conn_is_closed",
			failRecorderConnect: true,
			wantsSetupErr:       true,
			wantsConnClosed:     true,
			proto:               SPDYProtocol,
		},
		{
			name:                        "connection_fails_post-initial_connect_policy_is_to_fail_open_conn_stays_open",
			failRecorderConnPostConnect: true,
			failOpen:                    true,
			proto:                       SPDYProtocol,
		},
		{
			name:                        "connection_fails_post-initial_connect,_policy_is_to_fail_closed_conn_is_closed",
			failRecorderConnPostConnect: true,
			wantsConnClosed:             true,
			proto:                       SPDYProtocol,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			tc := &fakes.TestConn{}
			ch := make(chan error)
			h := &Hijacker{
				connectToRecorder: func(context.Context,
					[]netip.AddrPort,
					sessionrecording.DialFunc,
				) (wc io.WriteCloser, rec []*tailcfg.SSHRecordingAttempt, _ <-chan error, err error) {
					if tt.failRecorderConnect {
						err = errors.New("test")
					}
					return wc, rec, ch, err
				},
				failOpen: tt.failOpen,
				who:      &apitype.WhoIsResponse{Node: &tailcfg.Node{}, UserProfile: &tailcfg.UserProfile{}},
				log:      zl.Sugar(),
				ts:       &tsnet.Server{},
				req:      &http.Request{URL: &url.URL{}},
				proto:    tt.proto,
			}
			ctx := context.Background()
			_, err := h.setUpRecording(ctx, tc)
			if (err != nil) != tt.wantsSetupErr {
				t.Errorf("spdyHijacker.setupRecording() error = %v, wantErr %v", err, tt.wantsSetupErr)
				return
			}
			if tt.failRecorderConnPostConnect {
				select {
				case ch <- errors.New("err"):
				case <-time.After(time.Second * 15):
					t.Errorf("error from recorder conn was not read within 15 seconds")
				}
			}
			timeout := time.Second * 20
			// TODO (irbekrm): cover case where an error is received
			// over channel and the failure policy is to fail open
			// (test that connection remains open over some period
			// of time).
			if err := tstest.WaitFor(timeout, func() (err error) {
				if tt.wantsConnClosed != tc.IsClosed() {
					return fmt.Errorf("got connection state: %t, wants connection state: %t", tc.IsClosed(), tt.wantsConnClosed)
				}
				return nil
			}); err != nil {
				t.Errorf("connection did not reach the desired state within %s", timeout.String())
			}
			ctx.Done()
		})
	}
}
