package cliui_test

import (
	"bufio"
	"bytes"
	"context"
	"io"
	"strings"
	"sync/atomic"
	"testing"
	"time"

	"github.com/google/uuid"
	"github.com/stretchr/testify/require"
	"golang.org/x/xerrors"

	"github.com/coder/coder/cli/clibase"
	"github.com/coder/coder/cli/clitest"
	"github.com/coder/coder/cli/cliui"
	"github.com/coder/coder/coderd/util/ptr"
	"github.com/coder/coder/codersdk"
	"github.com/coder/coder/testutil"
)

func TestAgent(t *testing.T) {
	t.Parallel()

	for _, tc := range []struct {
		name    string
		iter    []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error
		logs    chan []codersdk.WorkspaceAgentStartupLog
		opts    cliui.AgentOptions
		want    []string
		wantErr bool
	}{
		{
			name: "Initial connection",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnecting
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.FirstConnectedAt = ptr.Ref(time.Now())
					return nil
				},
			},
			want: []string{
				"⧗ Waiting for the workspace agent to connect",
				"✔ Waiting for the workspace agent to connect",
				"⧗ Running workspace agent startup script (non-blocking)",
				"Notice: The startup script is still running and your workspace may be incomplete.",
				"For more information and troubleshooting, see",
			},
		},
		{
			name: "Initial connection timeout",
			opts: cliui.AgentOptions{
				FetchInterval: 1 * time.Millisecond,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnecting
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleStarting
					agent.StartedAt = ptr.Ref(time.Now())
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentTimeout
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.FirstConnectedAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleReady
					agent.ReadyAt = ptr.Ref(time.Now())
					return nil
				},
			},
			want: []string{
				"⧗ Waiting for the workspace agent to connect",
				"The workspace agent is having trouble connecting, wait for it to connect or restart your workspace.",
				"For more information and troubleshooting, see",
				"✔ Waiting for the workspace agent to connect",
				"⧗ Running workspace agent startup script (non-blocking)",
				"✔ Running workspace agent startup script (non-blocking)",
			},
		},
		{
			name: "Disconnected",
			opts: cliui.AgentOptions{
				FetchInterval: 1 * time.Millisecond,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentDisconnected
					agent.FirstConnectedAt = ptr.Ref(time.Now().Add(-1 * time.Minute))
					agent.LastConnectedAt = ptr.Ref(time.Now().Add(-1 * time.Minute))
					agent.DisconnectedAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleReady
					agent.StartedAt = ptr.Ref(time.Now().Add(-1 * time.Minute))
					agent.ReadyAt = ptr.Ref(time.Now())
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.LastConnectedAt = ptr.Ref(time.Now())
					return nil
				},
			},
			want: []string{
				"⧗ The workspace agent lost connection",
				"Wait for it to reconnect or restart your workspace.",
				"For more information and troubleshooting, see",
				"✔ The workspace agent lost connection",
			},
		},
		{
			name: "Startup script logs",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
				Wait:          true,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.FirstConnectedAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleStarting
					agent.StartedAt = ptr.Ref(time.Now())
					logs <- []codersdk.WorkspaceAgentStartupLog{
						{
							CreatedAt: time.Now(),
							Output:    "Hello world",
						},
					}
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleReady
					agent.ReadyAt = ptr.Ref(time.Now())
					logs <- []codersdk.WorkspaceAgentStartupLog{
						{
							CreatedAt: time.Now(),
							Output:    "Bye now",
						},
					}
					return nil
				},
			},
			want: []string{
				"⧗ Running workspace agent startup script",
				"Hello world",
				"Bye now",
				"✔ Running workspace agent startup script",
			},
		},
		{
			name: "Startup script exited with error",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
				Wait:          true,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.FirstConnectedAt = ptr.Ref(time.Now())
					agent.StartedAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleStartError
					agent.ReadyAt = ptr.Ref(time.Now())
					logs <- []codersdk.WorkspaceAgentStartupLog{
						{
							CreatedAt: time.Now(),
							Output:    "Hello world",
						},
					}
					return nil
				},
			},
			want: []string{
				"⧗ Running workspace agent startup script",
				"Hello world",
				"✘ Running workspace agent startup script",
				"Warning: The startup script exited with an error and your workspace may be incomplete.",
				"For more information and troubleshooting, see",
			},
		},
		{
			name: "Error when shutting down",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentDisconnected
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleOff
					return nil
				},
			},
			wantErr: true,
		},
		{
			name: "Error when shutting down while waiting",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
				Wait:          true,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnected
					agent.FirstConnectedAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleStarting
					agent.StartedAt = ptr.Ref(time.Now())
					logs <- []codersdk.WorkspaceAgentStartupLog{
						{
							CreatedAt: time.Now(),
							Output:    "Hello world",
						},
					}
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, logs chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.ReadyAt = ptr.Ref(time.Now())
					agent.LifecycleState = codersdk.WorkspaceAgentLifecycleShuttingDown
					return nil
				},
			},
			want: []string{
				"⧗ Running workspace agent startup script",
				"Hello world",
				"✔ Running workspace agent startup script",
			},
			wantErr: true,
		},
		{
			name: "Error during fetch",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
				Wait:          true,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentConnecting
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					return xerrors.New("bad")
				},
			},
			want: []string{
				"⧗ Waiting for the workspace agent to connect",
			},
			wantErr: true,
		},
		{
			name: "Shows agent troubleshooting URL",
			opts: cliui.AgentOptions{
				FetchInterval: time.Millisecond,
				Wait:          true,
			},
			iter: []func(context.Context, *codersdk.WorkspaceAgent, chan []codersdk.WorkspaceAgentStartupLog) error{
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					agent.Status = codersdk.WorkspaceAgentTimeout
					agent.TroubleshootingURL = "https://troubleshoot"
					return nil
				},
				func(_ context.Context, agent *codersdk.WorkspaceAgent, _ chan []codersdk.WorkspaceAgentStartupLog) error {
					return xerrors.New("bad")
				},
			},
			want: []string{
				"⧗ Waiting for the workspace agent to connect",
				"The workspace agent is having trouble connecting, wait for it to connect or restart your workspace.",
				"https://troubleshoot",
			},
			wantErr: true,
		},
	} {
		tc := tc
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitShort)
			defer cancel()

			var buf bytes.Buffer
			agent := codersdk.WorkspaceAgent{
				ID:                    uuid.New(),
				Status:                codersdk.WorkspaceAgentConnecting,
				StartupScriptBehavior: codersdk.WorkspaceAgentStartupScriptBehaviorNonBlocking,
				CreatedAt:             time.Now(),
				LifecycleState:        codersdk.WorkspaceAgentLifecycleCreated,
			}
			logs := make(chan []codersdk.WorkspaceAgentStartupLog, 1)

			cmd := &clibase.Cmd{
				Handler: func(inv *clibase.Invocation) error {
					tc.opts.Fetch = func(_ context.Context, _ uuid.UUID) (codersdk.WorkspaceAgent, error) {
						var err error
						if len(tc.iter) > 0 {
							err = tc.iter[0](ctx, &agent, logs)
							tc.iter = tc.iter[1:]
						}
						return agent, err
					}
					tc.opts.FetchLogs = func(ctx context.Context, _ uuid.UUID, _ int64, follow bool) (<-chan []codersdk.WorkspaceAgentStartupLog, io.Closer, error) {
						if follow {
							return logs, closeFunc(func() error { return nil }), nil
						}

						fetchLogs := make(chan []codersdk.WorkspaceAgentStartupLog, 1)
						select {
						case <-ctx.Done():
							return nil, nil, ctx.Err()
						case l := <-logs:
							fetchLogs <- l
						default:
						}
						close(fetchLogs)
						return fetchLogs, closeFunc(func() error { return nil }), nil
					}
					err := cliui.Agent(inv.Context(), &buf, uuid.Nil, tc.opts)
					return err
				},
			}
			inv := cmd.Invoke()

			w := clitest.StartWithWaiter(t, inv)
			if tc.wantErr {
				w.RequireError()
			} else {
				w.RequireSuccess()
			}

			s := bufio.NewScanner(&buf)
			for s.Scan() {
				line := s.Text()
				t.Log(line)
				if len(tc.want) == 0 {
					require.Fail(t, "unexpected line: "+line)
				}
				require.Contains(t, line, tc.want[0])
				tc.want = tc.want[1:]
			}
			require.NoError(t, s.Err())
			if len(tc.want) > 0 {
				require.Fail(t, "missing lines: "+strings.Join(tc.want, ", "))
			}
		})
	}

	t.Run("NotInfinite", func(t *testing.T) {
		t.Parallel()
		var fetchCalled uint64

		cmd := &clibase.Cmd{
			Handler: func(inv *clibase.Invocation) error {
				buf := bytes.Buffer{}
				err := cliui.Agent(inv.Context(), &buf, uuid.Nil, cliui.AgentOptions{
					FetchInterval: 10 * time.Millisecond,
					Fetch: func(ctx context.Context, agentID uuid.UUID) (codersdk.WorkspaceAgent, error) {
						atomic.AddUint64(&fetchCalled, 1)

						return codersdk.WorkspaceAgent{
							Status:         codersdk.WorkspaceAgentConnected,
							LifecycleState: codersdk.WorkspaceAgentLifecycleReady,
						}, nil
					},
				})
				if err != nil {
					return err
				}

				require.Never(t, func() bool {
					called := atomic.LoadUint64(&fetchCalled)
					return called > 5 || called == 0
				}, time.Second, 100*time.Millisecond)

				return nil
			},
		}
		require.NoError(t, cmd.Invoke().Run())
	})
}