From fbe030d85a80afa7818884f942d124d856224013 Mon Sep 17 00:00:00 2001
From: Tim Culverhouse <tim@timculverhouse.com>
Date: Wed, 20 Sep 2023 18:57:06 -0500
Subject: [PATCH] terminal: respond to XTVERSION query

XTVERSION (CSI > 0 q) is used by some libraries to identify the terminal
+ version. Respond to this query with `ghostty {version_string}`. There
is no formal format for this response. A roundup of a few tested
terminals show two primary formats. This patch opts to save one byte and
use the `name SP version` semantics.

foot: foot(version)
xterm: XTerm(version)
contour: contour version
wezterm: wezterm version

Reference: https://github.com/dankamongmen/notcurses/blob/master/TERMINALS.md#notes-for-terminal-authors
Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
---
 src/terminal/stream.zig | 38 +++++++++++++++++++++-----------------
 src/termio/Exec.zig     | 17 +++++++++++++++++
 2 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/src/terminal/stream.zig b/src/terminal/stream.zig
index 3789d5611..585e49212 100644
--- a/src/terminal/stream.zig
+++ b/src/terminal/stream.zig
@@ -607,28 +607,32 @@ pub fn Stream(comptime Handler: type) type {
                     ),
                 },
 
-                // DECSCUSR - Select Cursor Style
-                // TODO: test
                 'q' => switch (action.intermediates.len) {
-                    1 => cursor: {
-                        if (action.intermediates[0] != ' ') {
+                    1 => switch (action.intermediates[0]) {
+                        // DECSCUSR - Select Cursor Style
+                        // TODO: test
+                        ' ' => {
+                            if (@hasDecl(T, "setCursorStyle")) try self.handler.setCursorStyle(
+                                switch (action.params.len) {
+                                    0 => ansi.CursorStyle.default,
+                                    1 => @enumFromInt(action.params[0]),
+                                    else => {
+                                        log.warn("invalid set curor style command: {}", .{action});
+                                        return;
+                                    },
+                                },
+                            ) else log.warn("unimplemented CSI callback: {}", .{action});
+                        },
+                        // XTVERSION
+                        '>' => {
+                            if (@hasDecl(T, "reportXtversion")) try self.handler.reportXtversion();
+                        },
+                        else => {
                             log.warn(
                                 "ignoring unimplemented CSI q with intermediates: {s}",
                                 .{action.intermediates},
                             );
-                            break :cursor;
-                        }
-
-                        if (@hasDecl(T, "setCursorStyle")) try self.handler.setCursorStyle(
-                            switch (action.params.len) {
-                                0 => ansi.CursorStyle.default,
-                                1 => @enumFromInt(action.params[0]),
-                                else => {
-                                    log.warn("invalid set curor style command: {}", .{action});
-                                    return;
-                                },
-                            },
-                        ) else log.warn("unimplemented CSI callback: {}", .{action});
+                        },
                     },
 
                     else => log.warn(
diff --git a/src/termio/Exec.zig b/src/termio/Exec.zig
index 739ae3702..ef2d796c7 100644
--- a/src/termio/Exec.zig
+++ b/src/termio/Exec.zig
@@ -1688,6 +1688,23 @@ const StreamHandler = struct {
         self.terminal.screen.kitty_keyboard.set(mode, flags);
     }
 
+    pub fn reportXtversion(
+        self: *StreamHandler,
+    ) !void {
+        log.debug("reporting XTVERSION: ghostty {s}", .{build_config.version_string});
+        var msg: termio.Message = .{ .write_small = .{} };
+        const resp = try std.fmt.bufPrint(
+            &msg.write_small.data,
+            "\x1BP>|{s} {s}\x07",
+            .{
+                "ghostty",
+                build_config.version_string,
+            },
+        );
+        msg.write_small.len = @intCast(resp.len);
+        self.messageWriter(msg);
+    }
+
     //-------------------------------------------------------------------------
     // OSC