//go:build !windows

package tui

import (
	"bufio"
	"context"
	"errors"
	"fmt"
	"io"
	"os"
	"os/exec"
	"os/signal"
	"syscall"
	"testing"
	"time"

	tea "charm.land/bubbletea/v2"
	"gitgud.io/mike/mpv-manager/pkg/config"
	"gitgud.io/mike/mpv-manager/pkg/constants"
	"gitgud.io/mike/mpv-manager/pkg/installer"
	"github.com/stretchr/testify/require"
)

func TestProgramSIGTERMDrainsCommittedWorker(t *testing.T) {
	if os.Getenv("MPV_TUI_SIGNAL_CHILD") == "1" {
		sandboxConfigHome(t)
		m := NewModel()
		m.state, m.installing, m.installOperationType = StateInstalling, true, OpTypeUIChange
		m.selectedUIApp = &config.InstalledApp{ID: "signal-app", AppName: "MPV", InstallMethod: constants.MethodMPVBinary}
		m.releaseInfoLoader = func() (*installer.ReleaseInfo, error) { return nil, errors.New("offline fixture") }
		ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGTERM)
		defer stop()
		workerCtx, cancelWorker := context.WithCancel(context.Background())
		defer cancelWorker()
		output, result := make(chan string), make(chan error, 1)
		entered := make(chan struct{})
		guard := launchOperationWorker(workerCtx, output, result, func(ctx context.Context, cr *installer.CommandRunner) error {
			if err := cr.BeginCommit(); err != nil {
				return err
			}
			close(entered)
			var byte [1]byte
			if _, err := io.ReadFull(os.Stdin, byte[:]); err != nil {
				return err
			}
			if err := ctx.Err(); err != nil {
				return err
			}
			output <- "committed signal worker drained"
			return nil
		})
		m.ownOperation(saveChannelsMsg{outputChan: output, installDone: result, cancel: cancelWorker, commitGuard: guard})
		<-entered
		fmt.Println("SIGNAL_READY")
		err := m.Run(ctx, tea.WithInput(nil), tea.WithOutput(io.Discard), tea.WithoutRenderer())
		require.ErrorIs(t, err, context.Canceled)
		path, err := jobHistoryFilePath()
		require.NoError(t, err)
		records, err := loadJobHistoryRecords(path)
		require.NoError(t, err)
		require.Len(t, records, 1)
		require.Equal(t, "complete", records[0].Status)
		require.Contains(t, m.installOutput, "committed signal worker drained")
		return
	}
	child := exec.Command(os.Args[0], "-test.run=^TestProgramSIGTERMDrainsCommittedWorker$", "-test.timeout=20s")
	child.Env = append(os.Environ(), "MPV_TUI_SIGNAL_CHILD=1")
	stdout, err := child.StdoutPipe()
	require.NoError(t, err)
	stdin, err := child.StdinPipe()
	require.NoError(t, err)
	child.Stderr = os.Stderr
	require.NoError(t, child.Start())
	t.Cleanup(func() { _ = child.Process.Kill() })
	ready := make(chan bool, 1)
	go func() {
		scanner := bufio.NewScanner(stdout)
		for scanner.Scan() {
			if scanner.Text() == "SIGNAL_READY" {
				ready <- true
			}
		}
		ready <- false
	}()
	select {
	case ok := <-ready:
		require.True(t, ok)
	case <-time.After(10 * time.Second):
		t.Fatal("child never reached commit")
	}
	done := make(chan error, 1)
	go func() { done <- child.Wait() }()
	require.NoError(t, child.Process.Signal(syscall.SIGTERM))
	select {
	case err := <-done:
		t.Fatalf("signal abandoned worker: %v", err)
	case <-time.After(150 * time.Millisecond):
	}
	_, err = stdin.Write([]byte("\n"))
	require.NoError(t, err)
	_ = stdin.Close()
	select {
	case err := <-done:
		require.NoError(t, err)
	case <-time.After(10 * time.Second):
		t.Fatal("child failed to drain")
	}
}