parser: handle parsing of apc, sos, pm strings

This lets us detect kitty graphics.

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>

src/Parser.zig

@@ -444,6 +444,46 @@ pub fn parse(self: *Parser, input: []const u8) !Result {
                     },
                 }
             },
+            .apc => {
+                switch (b) {
+                    0x1B => {
+                        state = .ground;
+                        // advance one more for the backslash
+                        i += 1;
+                        switch (input[start + 1]) {
+                            'G' => {
+                                return .{
+                                    .event = .cap_kitty_graphics,
+                                    .n = i + 1,
+                                };
+                            },
+                            else => {
+                                log.warn("unhandled apc: APC {s}", .{input[start + 1 .. i + 1]});
+                                return .{
+                                    .event = null,
+                                    .n = i + 1,
+                                };
+                            },
+                        }
+                    },
+                    else => {},
+                }
+            },
+            .sos, .pm => {
+                switch (b) {
+                    0x1B => {
+                        state = .ground;
+                        // advance one more for the backslash
+                        i += 1;
+                        log.warn("unhandled sos/pm: SOS/PM {s}", .{input[start + 1 .. i + 1]});
+                        return .{
+                            .event = null,
+                            .n = i + 1,
+                        };
+                    },
+                    else => {},
+                }
+            },
             else => {},
         }
     }

src/Tty.zig

@@ -178,9 +178,15 @@ pub fn run(
                     }
                 },
                 .cap_kitty_keyboard => {
-                    log.info("kitty capability detected", .{});
+                    log.info("kitty keyboard capability detected", .{});
                     vx.caps.kitty_keyboard = true;
                 },
+                .cap_kitty_graphics => {
+                    if (!vx.caps.kitty_graphics) {
+                        log.info("kitty graphics capability detected", .{});
+                        vx.caps.kitty_graphics = true;
+                    }
+                },
                 .cap_rgb => {
                     log.info("rgb capability detected", .{});
                     vx.caps.rgb = true;

src/event.zig

@@ -10,6 +10,7 @@ pub const Event = union(enum) {
 
     // these are delivered as discovered terminal capabilities
     cap_kitty_keyboard,
+    cap_kitty_graphics,
     cap_rgb,
     cap_unicode,
     cap_da1,

src/vaxis.zig

@@ -222,10 +222,7 @@ pub fn Vaxis(comptime T: type) type {
             // that
             // _ = try tty.write(ctlseqs.xtversion);
             _ = try tty.write(ctlseqs.csi_u_query);
-            // TODO: KITTY_GRAPHICS has an APC response. uncomment when we can
+            _ = try tty.write(ctlseqs.kitty_graphics_query);
-            // parse that
-            // that
-            // _ = try tty.write(ctlseqs.kitty_graphics_query);
             // TODO: sixel geometry query interferes with F4 keys.
             // _ = try tty.write(ctlseqs.sixel_geometry_query);
 
@@ -590,6 +587,7 @@ pub fn Vaxis(comptime T: type) type {
             alloc: std.mem.Allocator,
             src: Image.Source,
         ) !Image {
+            if (!self.caps.kitty_graphics) return error.NoGraphicsCapability;
             var tty = self.tty orelse return error.NoTTY;
             defer self.next_img_id += 1;