v7.1.8

2026-06-09 06:06:52 +07:00
parent 31e9ecac35
commit 954cfe9d4f
53 changed files with 2910 additions and 912 deletions
@@ -0,0 +1,129 @@
+package backend
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+)
+
+var ErrDownloadCancelled = errors.New("download cancelled")
+
+var downloadCancelState = struct {
+	sync.Mutex
+	ctx      context.Context
+	cancel   context.CancelFunc
+	active   int
+	stopping bool
+}{}
+
+func BeginDownloadCancellationScope() (context.Context, func()) {
+	downloadCancelState.Lock()
+	defer downloadCancelState.Unlock()
+
+	if downloadCancelState.ctx == nil || downloadCancelState.active == 0 {
+		downloadCancelState.ctx, downloadCancelState.cancel = context.WithCancel(context.Background())
+		downloadCancelState.stopping = false
+	}
+
+	downloadCancelState.active++
+	ctx := downloadCancelState.ctx
+	once := sync.Once{}
+
+	return ctx, func() {
+		once.Do(func() {
+			downloadCancelState.Lock()
+			defer downloadCancelState.Unlock()
+
+			if downloadCancelState.active > 0 {
+				downloadCancelState.active--
+			}
+			if downloadCancelState.active == 0 {
+				if downloadCancelState.cancel != nil {
+					downloadCancelState.cancel()
+				}
+				downloadCancelState.ctx = nil
+				downloadCancelState.cancel = nil
+				downloadCancelState.stopping = false
+			}
+		})
+	}
+}
+
+func ActiveDownloadContext() context.Context {
+	downloadCancelState.Lock()
+	defer downloadCancelState.Unlock()
+
+	if downloadCancelState.ctx == nil {
+		return context.Background()
+	}
+	return downloadCancelState.ctx
+}
+
+func ForceStopActiveDownloads() {
+	downloadCancelState.Lock()
+	cancel := downloadCancelState.cancel
+	if cancel != nil {
+		downloadCancelState.stopping = true
+	}
+	downloadCancelState.Unlock()
+
+	if cancel != nil {
+		cancel()
+	}
+
+	CancelQueuedAndDownloadingItems()
+	SetDownloading(false)
+}
+
+func IsDownloadForceStopRequested() bool {
+	downloadCancelState.Lock()
+	defer downloadCancelState.Unlock()
+
+	return downloadCancelState.stopping
+}
+
+func CheckDownloadCancelled() error {
+	ctx := ActiveDownloadContext()
+	select {
+	case <-ctx.Done():
+		return ErrDownloadCancelled
+	default:
+		return nil
+	}
+}
+
+func SleepWithDownloadContext(delay time.Duration) error {
+	if delay <= 0 {
+		return CheckDownloadCancelled()
+	}
+
+	ctx := ActiveDownloadContext()
+	timer := time.NewTimer(delay)
+	defer timer.Stop()
+
+	select {
+	case <-ctx.Done():
+		return ErrDownloadCancelled
+	case <-timer.C:
+		return nil
+	}
+}
+
+func IsDownloadCancelledError(err error) bool {
+	if err == nil {
+		return false
+	}
+	return errors.Is(err, ErrDownloadCancelled) || errors.Is(err, context.Canceled)
+}
+
+func WrapDownloadCancelled(err error) error {
+	if err == nil {
+		return nil
+	}
+	if IsDownloadForceStopRequested() || errors.Is(err, context.Canceled) {
+		return fmt.Errorf("%w", ErrDownloadCancelled)
+	}
+	return err
+}