Cthulhu is no longer a fork. Now it is a screen reader written in Golang.

internal/app/braille_routing.go

@@ -0,0 +1,79 @@
+package app
+
+import (
+	"context"
+	"time"
+	"unicode/utf8"
+
+	"git.stormux.org/storm/cthulhu/internal/atspi"
+	"git.stormux.org/storm/cthulhu/internal/braille"
+)
+
+type brailleRouter interface {
+	RouteBraille(context.Context, atspi.BrailleRoute) error
+}
+
+func (worker *brailleWorker) route(ctx context.Context, event braille.RoutingEvent) {
+	worker.mu.Lock()
+	frame := worker.frame
+	length := utf8.RuneCountInString(frame.Text)
+	if worker.secure || worker.stopping || frame.ID == 0 || event.ID != frame.ID || event.Offset < 0 ||
+		(frame.Virtual == nil && event.Offset >= length) || (frame.Virtual != nil && event.Offset > length) {
+		worker.mu.Unlock()
+		return
+	}
+	if route := frame.Virtual; route != nil {
+		if worker.ocr == nil || event.Offset < route.Start || event.Offset > route.End {
+			worker.mu.Unlock()
+			return
+		}
+		routeCtx, cancel := context.WithTimeout(ctx, time.Second)
+		worker.routeCancel = cancel
+		worker.mu.Unlock()
+		defer cancel()
+		worker.ocr.RouteBraille(routeCtx, route.Generation, route.SourceStart+event.Offset-route.Start)
+		return
+	}
+	if worker.router == nil && frame.Document == nil {
+		worker.mu.Unlock()
+		return
+	}
+	var target *braille.TextRoute
+	for _, route := range frame.Routes {
+		if event.Offset >= route.Start && event.Offset < route.End {
+			target = &route
+			break
+		}
+	}
+	if target == nil {
+		worker.mu.Unlock()
+		return
+	}
+	routeCtx, cancel := context.WithTimeout(ctx, time.Second)
+	worker.routeCancel = cancel
+	worker.mu.Unlock()
+	defer cancel()
+	if document := frame.Document; document != nil {
+		if worker.document == nil {
+			return
+		}
+		worker.logger.Debug("routing document braille", "frame_id", frame.ID, "document_epoch", document.Epoch,
+			"source_bus", target.BusName, "source_path", target.Path, "source_start", target.SourceStart,
+			"native_offset", target.SourceStart+min(event.Offset-target.Start, target.TextLength))
+		err := worker.document.RouteDocumentBraille(routeCtx, document.Epoch,
+			atspi.NewObjectID(document.FocusBus, document.FocusPath), atspi.NewObjectID(document.DocumentBus, document.DocumentPath),
+			atspi.NewObjectID(target.BusName, target.Path), target.SourceText, target.SourceStart,
+			target.SourceStart+min(event.Offset-target.Start, target.TextLength))
+		if err != nil && routeCtx.Err() == nil {
+			worker.logger.Debug("document braille routing rejected", "error", err)
+		}
+		return
+	}
+	err := worker.router.RouteBraille(routeCtx, atspi.BrailleRoute{
+		Focus: atspi.NewObjectID(target.BusName, target.Path), Line: target.SourceText, Start: target.SourceStart,
+		Offset: target.SourceStart + min(event.Offset-target.Start, target.TextLength),
+	})
+	if err != nil && routeCtx.Err() == nil {
+		worker.logger.Debug("braille routing rejected", "error", err)
+	}
+}