grab all keys when needed

2 files changed, 117 insertions, 4 deletions

diff --git a/src/keys.rs b/src/keys.rs
index 6cf28a6..08dd056 100644
--- a/src/keys.rs
+++ b/src/keys.rs
@@ -1,12 +1,125 @@
 use crate::{error::*, WM};
-use xcb::x::{KeyPressEvent, MappingNotifyEvent};
+use xcb::x::{
+    GetKeyboardMapping, GetModifierMapping, GrabKey, GrabMode, KeyPressEvent, Keycode, Keysym,
+    Mapping, MappingNotifyEvent, ModMask, UngrabKey, GRAB_ANY,
+};
+
+// https://github.com/D-Programming-Deimos/libX11/blob/master/c/X11/keysymdef.h
+const KEYSYM_NUMLOCK: Keysym = 0xff7f;
 
 impl WM<'_> {
     pub(crate) fn handle_key_press(&mut self, e: KeyPressEvent) -> Result<()> {
-        todo!()
+        dbg!(e);
+
+        Ok(())
     }
 
     pub(crate) fn handle_mapping_notify(&mut self, e: MappingNotifyEvent) -> Result<()> {
-        todo!()
+        if e.request() == Mapping::Keyboard {
+            self.grabkeys()?;
+        }
+
+        Ok(())
+    }
+
+    pub(crate) fn grabkeys(&self) -> Result<()> {
+        let numlock_mask = self.get_numlock_mask()?;
+
+        // ungrab all keys
+        self.conn.send_request(&UngrabKey {
+            key: GRAB_ANY,
+            grab_window: self.root,
+            modifiers: ModMask::ANY,
+        });
+
+        // go through keymap and grab what we need
+        let (min_keycode, max_keycode) = (
+            self.conn.get_setup().min_keycode(),
+            self.conn.get_setup().max_keycode(),
+        );
+        let mapping = self
+            .conn
+            .wait_for_reply(self.conn.send_request(&GetKeyboardMapping {
+                first_keycode: min_keycode,
+                count: max_keycode - min_keycode + 1,
+            }))?;
+
+        for shift in 0..mapping.keysyms_per_keycode() {
+            for keycode in min_keycode..max_keycode {
+                let keysym = mapping.keysyms()
+                    [(shift as usize * mapping.keysyms_per_keycode() as usize + keycode as usize)];
+                if true {
+                    // todo: is bound
+                    // grab key with any combination of modifiers
+                    for modmask in [
+                        ModMask::empty(),
+                        ModMask::LOCK,
+                        numlock_mask,
+                        numlock_mask | ModMask::LOCK,
+                    ] {
+                        self.conn.send_request(&GrabKey {
+                            grab_window: self.root,
+                            key: keycode,
+                            modifiers: modmask,
+                            owner_events: true,
+                            pointer_mode: GrabMode::Async,
+                            keyboard_mode: GrabMode::Async,
+                        });
+                    }
+                }
+            }
+        }
+
+        // ensure all requests succeeded
+        self.conn.flush()?;
+
+        Ok(())
+    }
+
+    pub(crate) fn get_numlock_mask(&self) -> Result<ModMask> {
+        let map = self
+            .conn
+            .wait_for_reply(self.conn.send_request(&GetModifierMapping {}))?;
+        let numlock_keycode = self.keysym_to_keycode(KEYSYM_NUMLOCK)?;
+
+        let keypermod = map.keycodes().len() / 8;
+        for i in 0..8 {
+            for j in 0..keypermod {
+                if map.keycodes()[(i * keypermod + j) as usize] == numlock_keycode {
+                    return Ok(ModMask::from_bits(1 << i).expect("x11 has unrecognised modifier"));
+                }
+            }
+        }
+
+        // todo: is this ok?
+        return Ok(ModMask::empty());
+    }
+
+    pub(crate) fn keysym_to_keycode(&self, keysym: Keysym) -> Result<Keycode> {
+        let (min_keycode, max_keycode) = (
+            self.conn.get_setup().min_keycode(),
+            self.conn.get_setup().max_keycode(),
+        );
+        let mapping = self
+            .conn
+            .wait_for_reply(self.conn.send_request(&GetKeyboardMapping {
+                first_keycode: min_keycode,
+                count: max_keycode - min_keycode + 1,
+            }))?;
+
+        // todo: apparently there's an optimisation here https://github.com/ArcherPergande/xcbkeys/blob/main/xcbkeys.h
+        for shift in 0..mapping.keysyms_per_keycode() {
+            for keycode in min_keycode..max_keycode {
+                if mapping.keysyms()
+                    [keycode as usize * mapping.keysyms_per_keycode() as usize + shift as usize]
+                    == keysym
+                {
+                    return Ok(keycode);
+                }
+            }
+        }
+
+        // todo: is this right?
+        return Ok(0);
     }
 }
diff --git a/src/main.rs b/src/main.rs
index c2b32a0..f61f422 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -89,7 +89,7 @@ impl WM<'_> {
                 ],
             }))?;
 
-        // TODO: grab keys
+        self.grabkeys()?;
 
         // TODO: reset focus