fix: sync preserve iOS theme accent visibility

internal/compat/ios/theme_colors.go

@@ -0,0 +1,46 @@
+package ios
+
+import "github.com/iamxvbaba/td/tg"
+
+// ProjectThemes converts theme accent colors to the ARGB representation used by
+// Telegram-iOS. Official chat-theme seed colors are RGB24 values, while iOS
+// passes accent_color and outbox_accent_color to UIColor(argb:); a zero high
+// byte would therefore make every accent-tinted control fully transparent.
+//
+// The projection is copy-on-write so the Android/TDesktop catalog remains
+// byte-for-byte unchanged. message_colors and wallpaper colors intentionally
+// stay RGB24, as required by the TL schema and all audited clients.
+func ProjectThemes(themes []tg.Theme) []tg.Theme {
+	if len(themes) == 0 {
+		return nil
+	}
+	out := make([]tg.Theme, len(themes))
+	for i := range themes {
+		out[i] = themes[i]
+		settings, ok := themes[i].GetSettings()
+		if !ok {
+			continue
+		}
+		projected := make([]tg.ThemeSettings, len(settings))
+		for j := range settings {
+			projected[j] = settings[j]
+			projected[j].AccentColor = opaqueARGB(settings[j].AccentColor)
+			if color, ok := settings[j].GetOutboxAccentColor(); ok {
+				projected[j].SetOutboxAccentColor(opaqueARGB(color))
+			}
+			if colors, ok := settings[j].GetMessageColors(); ok {
+				projected[j].SetMessageColors(append([]int(nil), colors...))
+			}
+		}
+		out[i].SetSettings(projected)
+	}
+	return out
+}
+
+func opaqueARGB(color int) int {
+	value := uint32(int32(color))
+	if value>>24 == 0 {
+		value |= 0xff000000
+	}
+	return int(int32(value))
+}

internal/compat/ios/theme_colors_test.go

@@ -0,0 +1,75 @@
+package ios
+
+import (
+	"testing"
+
+	"github.com/iamxvbaba/td/tg"
+)
+
+func TestProjectThemesMakesOnlyIOSAccentColorsOpaque(t *testing.T) {
+	settings := tg.ThemeSettings{
+		BaseTheme:   &tg.BaseThemeClassic{},
+		AccentColor: 0x29b071,
+	}
+	settings.SetOutboxAccentColor(0x4cb064)
+	settings.SetMessageColors([]int{0xd4f1ff, 0xb9e4ff})
+	wallpaper := &tg.WallPaperNoFile{}
+	settings.SetWallpaper(wallpaper)
+	theme := tg.Theme{ID: 1, Slug: "green", Title: "Green"}
+	theme.SetSettings([]tg.ThemeSettings{settings})
+
+	projected := ProjectThemes([]tg.Theme{theme})
+	if len(projected) != 1 {
+		t.Fatalf("ProjectThemes length = %d, want 1", len(projected))
+	}
+	got, ok := projected[0].GetSettings()
+	if !ok || len(got) != 1 {
+		t.Fatalf("projected settings = %#v ok=%v, want one setting", got, ok)
+	}
+	if color := uint32(int32(got[0].AccentColor)); color != 0xff29b071 {
+		t.Fatalf("accent color = %#08x, want opaque ARGB 0xff29b071", color)
+	}
+	if color, ok := got[0].GetOutboxAccentColor(); !ok || uint32(int32(color)) != 0xff4cb064 {
+		t.Fatalf("outbox accent = %#08x ok=%v, want opaque ARGB 0xff4cb064", uint32(int32(color)), ok)
+	}
+	colors, ok := got[0].GetMessageColors()
+	if !ok || len(colors) != 2 || colors[0] != 0xd4f1ff || colors[1] != 0xb9e4ff {
+		t.Fatalf("message colors = %#v ok=%v, want unchanged RGB24 values", colors, ok)
+	}
+	if got[0].Wallpaper != wallpaper {
+		t.Fatal("wallpaper changed during accent-only projection")
+	}
+
+	sourceSettings, _ := theme.GetSettings()
+	if sourceSettings[0].AccentColor != 0x29b071 {
+		t.Fatalf("source accent mutated to %#x", sourceSettings[0].AccentColor)
+	}
+	sourceOutbox, _ := sourceSettings[0].GetOutboxAccentColor()
+	if sourceOutbox != 0x4cb064 {
+		t.Fatalf("source outbox accent mutated to %#x", sourceOutbox)
+	}
+	colors[0] = 1
+	sourceColors, _ := sourceSettings[0].GetMessageColors()
+	if sourceColors[0] != 0xd4f1ff {
+		t.Fatalf("source message colors mutated through projection: %#v", sourceColors)
+	}
+}
+
+func TestProjectThemesPreservesExistingAlphaAndAbsentOutbox(t *testing.T) {
+	argb := uint32(0x80445566)
+	settings := tg.ThemeSettings{
+		BaseTheme:   &tg.BaseThemeTinted{},
+		AccentColor: int(int32(argb)),
+	}
+	theme := tg.Theme{ID: 2}
+	theme.SetSettings([]tg.ThemeSettings{settings})
+
+	projected := ProjectThemes([]tg.Theme{theme})
+	got, _ := projected[0].GetSettings()
+	if color := uint32(int32(got[0].AccentColor)); color != argb {
+		t.Fatalf("existing ARGB color = %#08x, want %#08x", color, argb)
+	}
+	if _, ok := got[0].GetOutboxAccentColor(); ok {
+		t.Fatal("absent outbox accent became present")
+	}
+}