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

internal/app/autocomplete.go

@@ -0,0 +1,94 @@
+// Copyright (c) 2026 Storm Dragon
+// Authors: Storm Dragon, Angus Kola
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package app
+
+import (
+	"strings"
+
+	"git.stormux.org/storm/cthulhu/internal/atspi"
+	"git.stormux.org/storm/cthulhu/internal/input"
+)
+
+// Inline completions are selected by the browser. Echo the inserted portion
+// outside that selection; it contains the user's edit, not the suggested suffix.
+func autocompleteInsertion(event atspi.Event) string {
+	text := []rune(event.Payload)
+	start, end := event.Source.SelectionStart, event.Source.SelectionEnd
+	if end <= start || end <= event.Detail1 || start >= event.Detail1+len(text) {
+		return event.Payload
+	}
+	left := max(0, start-event.Detail1)
+	right := min(len(text), end-event.Detail1)
+	return string(text[:left]) + string(text[right:])
+}
+
+func recentInput(source any) input.Activity {
+	if provider, ok := source.(interface{ RecentInput() input.Activity }); ok {
+		return provider.RecentInput()
+	}
+	return input.Activity{}
+}
+
+type autocompleteEcho struct {
+	sequence uint64
+	source   atspi.ObjectID
+}
+
+// autocompleteAvailability presents the selected address when it changes.
+// Chromium can send several insertion and popup events for the same suggestion.
+type autocompleteAvailability struct {
+	entry       atspi.ObjectID
+	lastAddress string
+}
+
+func supportsAutocomplete(snapshot atspi.Snapshot) bool {
+	return snapshot.Autocomplete || snapshot.Role == "autocomplete"
+}
+
+func (availability *autocompleteAvailability) focus(event atspi.Event) {
+	if !isFocusGainEvent(event) || event.Source.AutocompletePopup {
+		return
+	}
+	entry := atspi.ObjectID{}
+	if supportsAutocomplete(event.Source) {
+		entry = event.Source.ID()
+	}
+	if entry != availability.entry {
+		availability.entry = entry
+		availability.lastAddress = ""
+	}
+}
+
+func (availability *autocompleteAvailability) offered(event atspi.Event, activity input.Activity) string {
+	if !availability.entry.Valid() || event.Type != atspi.TextInsertedEvent ||
+		!supportsAutocomplete(event.Source) || event.Source.ID() != availability.entry ||
+		(activity.Intent != input.TypingIntent && activity.Intent != input.DeleteIntent) {
+		return ""
+	}
+	address := strings.TrimSpace(event.Source.Text)
+	if event.Source.SelectionEnd <= event.Source.SelectionStart ||
+		event.Source.SelectionEnd > len([]rune(address)) || address == "" ||
+		address == availability.lastAddress {
+		return ""
+	}
+	availability.lastAddress = address
+	return address
+}
+
+func (echo *autocompleteEcho) insertion(event atspi.Event, activity input.Activity) string {
+	text := autocompleteInsertion(event)
+	if text == "" && activity.Sequence != 0 &&
+		(activity.Sequence != echo.sequence || event.Source.ID() != echo.source) &&
+		event.Detail1 == event.Source.SelectionStart {
+		// Chromium can retain an unchanged typed prefix and emit only a replacement
+		// of the selected suffix. Recover that character from accessible text once
+		// for this key press; a normal insertion already covers the other case.
+		text = event.Source.CompletionPrefixCharacter
+	}
+	if text != "" {
+		echo.sequence, echo.source = activity.Sequence, event.Source.ID()
+	}
+	return text
+}