From 89d07fcd83379a0c5c93391e2402982110438bb1 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Fri, 3 Mar 2023 09:27:47 -0800
Subject: [PATCH] clear_history binding, default Cmd+K

---
 src/Surface.zig        |  7 +++++++
 src/config.zig         |  6 ++++++
 src/input/Binding.zig  |  3 +++
 src/termio/Exec.zig    | 13 +++++++++++++
 src/termio/Thread.zig  |  1 +
 src/termio/message.zig |  6 ++++++
 6 files changed, 36 insertions(+)

diff --git a/src/Surface.zig b/src/Surface.zig
index 10d614365..202f398d2 100644
--- a/src/Surface.zig
+++ b/src/Surface.zig
@@ -896,6 +896,13 @@ pub fn keyCallback(
                     self.setFontSize(size);
                 },
 
+                .clear_screen => {
+                    _ = self.io_thread.mailbox.push(.{
+                        .clear_screen = .{ .history = true },
+                    }, .{ .forever = {} });
+                    try self.io_thread.wakeup.notify();
+                },
+
                 .toggle_dev_mode => if (DevMode.enabled) {
                     DevMode.instance.visible = !DevMode.instance.visible;
                     try self.queueRender();
diff --git a/src/config.zig b/src/config.zig
index 97987020d..06adb6910 100644
--- a/src/config.zig
+++ b/src/config.zig
@@ -192,6 +192,12 @@ pub const Config = struct {
             .{ .paste_from_clipboard = {} },
         );
 
+        try result.keybind.set.put(
+            alloc,
+            .{ .key = .k, .mods = .{ .super = true } },
+            .{ .clear_screen = {} },
+        );
+
         try result.keybind.set.put(alloc, .{ .key = .up }, .{ .cursor_key = .{
             .normal = "\x1b[A",
             .application = "\x1bOA",
diff --git a/src/input/Binding.zig b/src/input/Binding.zig
index 394e62c8c..a788d0c5e 100644
--- a/src/input/Binding.zig
+++ b/src/input/Binding.zig
@@ -146,6 +146,9 @@ pub const Action = union(enum) {
     /// Reset the font size to the original configured size
     reset_font_size: void,
 
+    /// Clear the screen. This also clears all scrollback.
+    clear_screen: void,
+
     /// Dev mode
     toggle_dev_mode: void,
 
diff --git a/src/termio/Exec.zig b/src/termio/Exec.zig
index d8d4d9cee..642dbef0a 100644
--- a/src/termio/Exec.zig
+++ b/src/termio/Exec.zig
@@ -194,6 +194,19 @@ pub fn resize(
     }
 }
 
+/// Clear the screen.
+pub fn clearScreen(self: *Exec, history: bool) !void {
+    // Queue form-feed ASCII code to clear the visible page.
+    try self.queueWrite(&[_]u8{0x0C});
+
+    // Clear our scrollback
+    if (history) {
+        self.renderer_state.mutex.lock();
+        defer self.renderer_state.mutex.unlock();
+        self.terminal.screen.clearHistory();
+    }
+}
+
 pub inline fn queueWrite(self: *Exec, data: []const u8) !void {
     const ev = self.data.?;
 
diff --git a/src/termio/Thread.zig b/src/termio/Thread.zig
index aa2a9c568..49ae661cc 100644
--- a/src/termio/Thread.zig
+++ b/src/termio/Thread.zig
@@ -130,6 +130,7 @@ fn drainMailbox(self: *Thread) !void {
         log.debug("mailbox message={}", .{message});
         switch (message) {
             .resize => |v| try self.impl.resize(v.grid_size, v.screen_size, v.padding),
+            .clear_screen => |v| try self.impl.clearScreen(v.history),
             .write_small => |v| try self.impl.queueWrite(v.data[0..v.len]),
             .write_stable => |v| try self.impl.queueWrite(v),
             .write_alloc => |v| {
diff --git a/src/termio/message.zig b/src/termio/message.zig
index 008093da0..a9f9a9006 100644
--- a/src/termio/message.zig
+++ b/src/termio/message.zig
@@ -29,6 +29,12 @@ pub const Message = union(enum) {
         padding: renderer.Padding,
     },
 
+    /// Clear the screen.
+    clear_screen: struct {
+        /// Include clearing the history
+        history: bool,
+    },
+
     /// Write where the data fits in the union.
     write_small: WriteReq.Small,