app: [macOS] implement IME support

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/os_macos.go

@@ -11,6 +11,7 @@ import (
 	"runtime"
 	"time"
 	"unicode"
+	"unicode/utf8"
 
 	"gioui.org/f32"
 	"gioui.org/io/clipboard"
@@ -154,6 +155,23 @@ static void raiseWindow(CFTypeRef windowRef) {
 	[window makeKeyAndOrderFront:nil];
 }
 
+static CFTypeRef createInputContext(CFTypeRef clientRef) {
+	@autoreleasepool {
+		id<NSTextInputClient> client = (__bridge id<NSTextInputClient>)clientRef;
+		NSTextInputContext *ctx = [[NSTextInputContext alloc] initWithClient:client];
+		return CFBridgingRetain(ctx);
+	}
+}
+
+static void discardMarkedText(CFTypeRef viewRef) {
+    @autoreleasepool {
+		id<NSTextInputClient> view = (__bridge id<NSTextInputClient>)viewRef;
+		NSTextInputContext *ctx = [NSTextInputContext currentInputContext];
+		if (view == [ctx client]) {
+			[ctx discardMarkedText];
+		}
+    }
+}
 */
 import "C"
 
@@ -344,7 +362,12 @@ func (w *window) SetCursor(name pointer.CursorName) {
 	w.cursor = windowSetCursor(w.cursor, name)
 }
 
-func (w *window) EditorStateChanged(old, new editorState) {}
+func (w *window) EditorStateChanged(old, new editorState) {
+	if old != new {
+		C.discardMarkedText(w.view)
+		w.w.SetComposingRegion(key.Range{Start: -1, End: -1})
+	}
+}
 
 func (w *window) ShowTextInput(show bool) {}
 
@@ -470,6 +493,133 @@ func gio_onChangeScreen(view C.CFTypeRef, did uint64) {
 	w.displayLink.SetDisplayID(did)
 }
 
+//export gio_hasMarkedText
+func gio_hasMarkedText(view C.CFTypeRef) C.int {
+	w := mustView(view)
+	state := w.w.EditorState()
+	if state.compose.Start != -1 {
+		return 1
+	}
+	return 0
+}
+
+//export gio_markedRange
+func gio_markedRange(view C.CFTypeRef) C.NSRange {
+	w := mustView(view)
+	state := w.w.EditorState()
+	rng := state.compose
+	start, end := rng.Start, rng.End
+	if start == -1 {
+		return C.NSMakeRange(C.NSNotFound, 0)
+	}
+	u16start := state.UTF16Index(start)
+	return C.NSMakeRange(
+		C.NSUInteger(u16start),
+		C.NSUInteger(state.UTF16Index(end)-u16start),
+	)
+}
+
+//export gio_selectedRange
+func gio_selectedRange(view C.CFTypeRef) C.NSRange {
+	w := mustView(view)
+	state := w.w.EditorState()
+	rng := state.Selection
+	start, end := rng.Start, rng.End
+	if start > end {
+		start, end = end, start
+	}
+	u16start := state.UTF16Index(start)
+	return C.NSMakeRange(
+		C.NSUInteger(u16start),
+		C.NSUInteger(state.UTF16Index(end)-u16start),
+	)
+}
+
+//export gio_unmarkText
+func gio_unmarkText(view C.CFTypeRef) {
+	w := mustView(view)
+	w.w.SetComposingRegion(key.Range{Start: -1, End: -1})
+}
+
+//export gio_setMarkedText
+func gio_setMarkedText(view, cstr C.CFTypeRef, selRange C.NSRange, replaceRange C.NSRange) {
+	w := mustView(view)
+	str := nsstringToString(cstr)
+	state := w.w.EditorState()
+	rng := state.compose
+	if rng.Start == -1 {
+		rng = state.Selection
+	}
+	if replaceRange.location != C.NSNotFound {
+		// replaceRange is relative to marked (or selected) text.
+		offset := state.UTF16Index(rng.Start)
+		start := state.RunesIndex(int(replaceRange.location) + offset)
+		end := state.RunesIndex(int(replaceRange.location+replaceRange.length) + offset)
+		rng = key.Range{
+			Start: start,
+			End:   end,
+		}
+	}
+	w.w.EditorReplace(rng, str)
+	comp := key.Range{
+		Start: rng.Start,
+		End:   rng.Start + utf8.RuneCountInString(str),
+	}
+	w.w.SetComposingRegion(comp)
+
+	sel := key.Range{Start: comp.End, End: comp.End}
+	if selRange.location != C.NSNotFound {
+		// selRange is relative to inserted text.
+		offset := state.UTF16Index(rng.Start)
+		start := state.RunesIndex(int(selRange.location) + offset)
+		end := state.RunesIndex(int(selRange.location+selRange.length) + offset)
+		sel = key.Range{
+			Start: start,
+			End:   end,
+		}
+	}
+	w.w.SetEditorSelection(sel)
+}
+
+//export gio_substringForProposedRange
+func gio_substringForProposedRange(view C.CFTypeRef, rng C.NSRange, actual C.NSRangePointer) C.CFTypeRef {
+	w := mustView(view)
+	state := w.w.EditorState()
+	start, end := state.Snippet.Start, state.Snippet.End
+	if start > end {
+		start, end = end, start
+	}
+	w.w.SetEditorSnippet(key.Range{
+		Start: state.RunesIndex(int(rng.location)),
+		End:   state.RunesIndex(int(rng.location + rng.length)),
+	})
+	u16start := state.UTF16Index(start)
+	actual.location = C.NSUInteger(u16start)
+	actual.length = C.NSUInteger(state.UTF16Index(end) - u16start)
+	return stringToNSString(state.Snippet.Text)
+}
+
+//export gio_insertText
+func gio_insertText(view, cstr C.CFTypeRef, crng C.NSRange) {
+	w := mustView(view)
+	state := w.w.EditorState()
+	rng := state.compose
+	if rng.Start == -1 {
+		rng = state.Selection
+	}
+	if crng.location != C.NSNotFound {
+		rng = key.Range{
+			Start: state.RunesIndex(int(crng.location)),
+			End:   state.RunesIndex(int(crng.location + crng.length)),
+		}
+	}
+	str := nsstringToString(cstr)
+	w.w.EditorReplace(rng, str)
+	w.w.SetComposingRegion(key.Range{Start: -1, End: -1})
+	pos := rng.Start + utf8.RuneCountInString(str)
+	w.w.SetEditorSelection(key.Range{Start: pos, End: pos})
+}
+
 func (w *window) draw() {
 	w.scale = float32(C.getViewBackingScale(w.view))
 	wf, hf := float32(C.viewWidth(w.view)), float32(C.viewHeight(w.view))
@@ -592,7 +742,7 @@ func newWindow(win *callbacks, options []Option) error {
 func newOSWindow() (*window, error) {
 	view := C.gio_createView()
 	if view == 0 {
-		return nil, errors.New("CreateWindow: failed to create view")
+		return nil, errors.New("newOSWindows: failed to create view")
 	}
 	scale := float32(C.getViewBackingScale(view))
 	w := &window{

app/os_macos.m

@@ -64,7 +64,7 @@ static void handleMouse(NSView *view, NSEvent *event, int typ, CGFloat dx, CGFlo
 	gio_onMouse((__bridge CFTypeRef)view, typ, [NSEvent pressedMouseButtons], p.x, height - p.y, dx, dy, [event timestamp], [event modifierFlags]);
 }
 
-@interface GioView : NSView <CALayerDelegate>
+@interface GioView : NSView <CALayerDelegate,NSTextInputClient>
 @end
 
 @implementation GioView
@@ -131,6 +131,58 @@ static void handleMouse(NSView *view, NSEvent *event, int typ, CGFloat dx, CGFlo
 	// Don't pass commands up the responder chain.
 	// They will end up in a beep.
 }
+
+- (BOOL)hasMarkedText {
+	int res = gio_hasMarkedText((__bridge CFTypeRef)self);
+	return res ? YES : NO;
+}
+- (NSRange)markedRange {
+	return gio_markedRange((__bridge CFTypeRef)self);
+}
+- (NSRange)selectedRange {
+	return gio_selectedRange((__bridge CFTypeRef)self);
+}
+- (void)unmarkText {
+	gio_unmarkText((__bridge CFTypeRef)self);
+}
+- (void)setMarkedText:(id)string
+        selectedRange:(NSRange)selRange
+     replacementRange:(NSRange)replaceRange {
+	NSString *str;
+	// string is either an NSAttributedString or an NSString.
+	if ([string isKindOfClass:[NSAttributedString class]]) {
+		str = [string string];
+	} else {
+		str = string;
+	}
+	gio_setMarkedText((__bridge CFTypeRef)self, (__bridge CFTypeRef)str, selRange, replaceRange);
+}
+- (NSArray<NSAttributedStringKey> *)validAttributesForMarkedText {
+	return nil;
+}
+- (NSAttributedString *)attributedSubstringForProposedRange:(NSRange)range
+                                                actualRange:(NSRangePointer)actualRange {
+	NSString *str = CFBridgingRelease(gio_substringForProposedRange((__bridge CFTypeRef)self, range, actualRange));
+	return [[NSAttributedString alloc] initWithString:str attributes:nil];
+}
+- (void)insertText:(id)string
+  replacementRange:(NSRange)replaceRange {
+	NSString *str;
+	// string is either an NSAttributedString or an NSString.
+	if ([string isKindOfClass:[NSAttributedString class]]) {
+		str = [string string];
+	} else {
+		str = string;
+	}
+	gio_insertText((__bridge CFTypeRef)self, (__bridge CFTypeRef)str, replaceRange);
+}
+- (NSUInteger)characterIndexForPoint:(NSPoint)point {
+	return NSNotFound;
+}
+- (NSRect)firstRectForCharacterRange:(NSRange)range
+                         actualRange:(NSRangePointer)actualRange {
+	return NSZeroRect;
+}
 @end
 
 // Delegates are weakly referenced from their peers. Nothing

app/window.go

@@ -149,6 +149,7 @@ func NewWindow(options ...Option) *Window {
 		dead:             make(chan struct{}),
 		nocontext:        cnf.CustomRenderer,
 	}
+	w.imeState.compose = key.Range{Start: -1, End: -1}
 	w.semantic.ids = make(map[router.SemanticID]router.SemanticNode)
 	w.callbacks.w = w
 	go w.run(options)
@@ -521,8 +522,10 @@ func (e *editorState) Replace(r key.Range, text string) {
 	}
 	e.Selection.Start = adjust(e.Selection.Start)
 	e.Selection.End = adjust(e.Selection.End)
-	e.compose.Start = adjust(e.compose.Start)
+	if e.compose.Start != -1 {
-	e.compose.End = adjust(e.compose.End)
+		e.compose.Start = adjust(e.compose.Start)
+		e.compose.End = adjust(e.compose.End)
+	}
 	s := e.Snippet
 	if r.End < s.Start || r.Start > s.End {
 		// Replacement does not overlap snippet.