config: window-theme, enum support for get

src/config/Config.zig

@@ -244,6 +244,14 @@ keybind: Keybinds = .{},
 /// borders.
 @"window-decoration": bool = true,
 
+/// The theme to use for the windows. The default is "system" which
+/// means that whatever the system theme is will be used. This can
+/// also be set to "light" or "dark" to force a specific theme regardless
+/// of the system settings.
+///
+/// This is currently only supported on macOS.
+@"window-theme": WindowTheme = .system,
+
 /// Whether to allow programs running in the terminal to read/write to
 /// the system clipboard (OSC 52, for googling). The default is to
 /// disallow clipboard reading but allow writing.
@@ -1507,3 +1515,10 @@ pub const OSCColorReportFormat = enum {
     @"8-bit",
     @"16-bit",
 };
+
+/// The default window theme.
+pub const WindowTheme = enum {
+    system,
+    light,
+    dark,
+};

src/config/c_get.zig

@@ -19,7 +19,7 @@ pub fn get(config: *const Config, k: Key, ptr_raw: *anyopaque) bool {
             const value = fieldByKey(config, tag);
             switch (@TypeOf(value)) {
                 ?[:0]const u8 => {
-                    const ptr: *[*c]const u8 = @ptrCast(@alignCast(ptr_raw));
+                    const ptr: *?[*:0]const u8 = @ptrCast(@alignCast(ptr_raw));
                     ptr.* = if (value) |slice| @ptrCast(slice.ptr) else null;
                 },
 
@@ -38,7 +38,14 @@ pub fn get(config: *const Config, k: Key, ptr_raw: *anyopaque) bool {
                     ptr.* = @floatCast(value);
                 },
 
-                else => return false,
+                else => |T| switch (@typeInfo(T)) {
+                    .Enum => {
+                        const ptr: *[*:0]const u8 = @ptrCast(@alignCast(ptr_raw));
+                        ptr.* = @tagName(value);
+                    },
+
+                    else => return false,
+                },
             }
 
             return true;
@@ -74,3 +81,18 @@ test "u8" {
     try testing.expect(get(&c, .@"font-size", &cval));
     try testing.expectEqual(@as(c_uint, 24), cval);
 }
+
+test "enum" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var c = try Config.default(alloc);
+    defer c.deinit();
+    c.@"window-theme" = .dark;
+
+    var cval: [*:0]u8 = undefined;
+    try testing.expect(get(&c, .@"window-theme", @ptrCast(&cval)));
+
+    const str = std.mem.sliceTo(cval, 0);
+    try testing.expectEqualStrings("dark", str);
+}