From 039f9231de874f49c4300a380f768d5dfda8f400 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <m@mitchellh.com>
Date: Wed, 13 Nov 2024 19:46:23 -0800
Subject: [PATCH] terminal: parse CSI 22/23 for push/pop title

Related to #2668

This just implements the VT stream parsing. The actual handling of these
events still needs to be done.
---
 src/terminal/csi.zig    |   8 ++
 src/terminal/stream.zig | 165 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 173 insertions(+)

diff --git a/src/terminal/csi.zig b/src/terminal/csi.zig
index d2ee4da46..0cab9ed52 100644
--- a/src/terminal/csi.zig
+++ b/src/terminal/csi.zig
@@ -40,3 +40,11 @@ pub const SizeReportStyle = enum {
     csi_18_t,
     csi_21_t,
 };
+
+/// XTWINOPS CSI 22/23
+pub const TitlePushPop = struct {
+    op: Op,
+    index: u16,
+
+    pub const Op = enum { push, pop };
+};
diff --git a/src/terminal/stream.zig b/src/terminal/stream.zig
index 703abbb38..b8d60a13f 100644
--- a/src/terminal/stream.zig
+++ b/src/terminal/stream.zig
@@ -1162,6 +1162,33 @@ pub fn Stream(comptime Handler: type) type {
                                     "ignoring CSI 21 t with extra parameters: {s}",
                                     .{input},
                                 ),
+                                inline 22, 23 => |number| if ((input.params.len == 2 or
+                                    input.params.len == 3) and
+                                    // we only support window title
+                                    (input.params[1] == 0 or
+                                    input.params[1] == 2))
+                                {
+                                    // push/pop title
+                                    if (@hasDecl(T, "pushPopTitle")) {
+                                        self.handler.pushPopTitle(.{
+                                            .op = switch (number) {
+                                                22 => .push,
+                                                23 => .pop,
+                                                else => @compileError("unreachable"),
+                                            },
+                                            .index = if (input.params.len == 3)
+                                                input.params[2]
+                                            else
+                                                0,
+                                        });
+                                    } else log.warn(
+                                        "ignoring unimplemented CSI 22/23 t",
+                                        .{},
+                                    );
+                                } else log.warn(
+                                    "ignoring CSI 22/23 t with extra parameters: {s}",
+                                    .{input},
+                                ),
                                 else => log.warn(
                                     "ignoring CSI t with unimplemented parameter: {s}",
                                     .{input},
@@ -2162,3 +2189,141 @@ test "stream: invalid CSI t" {
     try s.nextSlice("\x1b[19t");
     try testing.expectEqual(null, s.handler.style);
 }
+
+test "stream: CSI t push title" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[22;0t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .push,
+        .index = 0,
+    }, s.handler.op.?);
+}
+
+test "stream: CSI t push title with explicit window" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[22;2t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .push,
+        .index = 0,
+    }, s.handler.op.?);
+}
+
+test "stream: CSI t push title with explicit icon" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[22;1t");
+    try testing.expectEqual(null, s.handler.op);
+}
+
+test "stream: CSI t push title with index" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[22;0;5t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .push,
+        .index = 5,
+    }, s.handler.op.?);
+}
+
+test "stream: CSI t pop title" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[23;0t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .pop,
+        .index = 0,
+    }, s.handler.op.?);
+}
+
+test "stream: CSI t pop title with explicit window" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[23;2t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .pop,
+        .index = 0,
+    }, s.handler.op.?);
+}
+
+test "stream: CSI t pop title with explicit icon" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[23;1t");
+    try testing.expectEqual(null, s.handler.op);
+}
+
+test "stream: CSI t pop title with index" {
+    const H = struct {
+        op: ?csi.TitlePushPop = null,
+
+        pub fn pushPopTitle(self: *@This(), op: csi.TitlePushPop) void {
+            self.op = op;
+        }
+    };
+
+    var s: Stream(H) = .{ .handler = .{} };
+
+    try s.nextSlice("\x1b[23;0;5t");
+    try testing.expectEqual(csi.TitlePushPop{
+        .op = .pop,
+        .index = 5,
+    }, s.handler.op.?);
+}