core: layout: store availability of text insertion

src/core/button.rs

@@ -204,6 +204,12 @@ impl<D: Display, K: Keyboard> Button<D, K> {
         &self.modifiers
     }
 
+    #[inline(always)]
+    pub fn set_text_supported(&mut self, text_supp: bool)
+    {
+        self.layout.set_text_supported(text_supp)
+    }
+
     #[inline(always)]
     pub fn update_keys_supported(&mut self)
     {

src/core/layout.rs

@@ -72,6 +72,7 @@ pub struct Part {
     val: KeyValue,
 
     key_avail: bool,
+    text_avail: bool,
 
     presses: u32,
 }
@@ -298,6 +299,41 @@ impl Part {
         }
     }
 
+    fn keyvalue_has_text(val: &KeyValue) -> bool
+    {
+        match val {
+            KeyValue(Keysym::BackSpace, _) => false,
+            KeyValue(Keysym::Tab, _) => false,
+            KeyValue(Keysym::Return, _) => false,
+            KeyValue(Keysym::Escape, _) => false,
+            KeyValue(Keysym::Home, _) => false,
+            KeyValue(Keysym::Left, _) => false,
+            KeyValue(Keysym::Up, _) => false,
+            KeyValue(Keysym::Right, _) => false,
+            KeyValue(Keysym::Down, _) => false,
+            KeyValue(Keysym::Prior, _) => false,
+            KeyValue(Keysym::Next, _) => false,
+            KeyValue(Keysym::End, _) => false,
+            KeyValue(Keysym::F1, _) => false,
+            KeyValue(Keysym::F2, _) => false,
+            KeyValue(Keysym::F3, _) => false,
+            KeyValue(Keysym::F4, _) => false,
+            KeyValue(Keysym::F5, _) => false,
+            KeyValue(Keysym::F6, _) => false,
+            KeyValue(Keysym::F7, _) => false,
+            KeyValue(Keysym::F8, _) => false,
+            KeyValue(Keysym::F9, _) => false,
+            KeyValue(Keysym::F10, _) => false,
+            KeyValue(Keysym::F11, _) => false,
+            KeyValue(Keysym::F12, _) => false,
+            KeyValue(Keysym::Delete, _) => false,
+
+            KeyValue(_, l) => l != "",
+
+            _ => true,
+        }
+    }
+
     fn new(orig: KeyValue) -> Part
     {
         let val = Self::modify_no_fn(&orig);
@@ -307,6 +343,7 @@ impl Part {
             val,
 
             key_avail: false,
+            text_avail: false,
 
             presses: 0,
         }
@@ -336,12 +373,23 @@ impl Part {
         self.presses
     }
 
+    #[inline(always)]
+    pub fn text_available(&self) -> bool
+    {
+        self.text_avail
+    }
+
     #[inline(always)]
     pub fn key_available(&self) -> bool
     {
         self.key_avail
     }
 
+    fn set_text_supported(&mut self, text_supp: bool)
+    {
+        self.text_avail = text_supp && Self::keyvalue_has_text(&self.val);
+    }
+
     fn update_keys_supported<K: Keyboard>(&mut self, kbd: &K)
     {
         let key_supp = kbd.key_supported(self.val.0);
@@ -361,7 +409,8 @@ impl Part {
 
     pub fn update_modifiers<K: Keyboard>(&mut self,
                                          kbd: &K,
-                                         mod_state: &[ModState])
+                                         mod_state: &[ModState],
+                                         text_avail: bool)
     {
         let mut val = self.orig.clone();
 
@@ -377,6 +426,7 @@ impl Part {
 
         let key_supp = kbd.key_supported(self.val.0);
         self.key_avail = self.val.0 != Keysym::NoSymbol && key_supp;
+        self.text_avail = text_avail && Self::keyvalue_has_text(&val);
         self.val = val;
     }
 
@@ -432,6 +482,8 @@ pub struct Layout {
     height: f64,
     row_width: f64,
     in_row: u32,
+
+    text_supp: bool,
 }
 
 const KEYSYMS: [(&str, Keysym, &str); 20] = [
@@ -574,6 +626,7 @@ impl Layout {
             height: 0.0,
             row_width: 0.0,
             in_row: 0,
+            text_supp: false,
         };
 
         let mut vec = Vec::new();
@@ -678,7 +731,20 @@ impl Layout {
         for row in self.rows.iter_mut() {
             for key in row.iter_mut() {
                 for part in key.parts.iter_mut() {
-                    part.update_modifiers(kbd, mod_state);
+                    part.update_modifiers(kbd, mod_state, self.text_supp);
+                }
+            }
+        }
+    }
+
+    pub fn set_text_supported(&mut self, text_supp: bool)
+    {
+        self.text_supp = text_supp;
+
+        for row in self.rows.iter_mut() {
+            for key in row.iter_mut() {
+                for part in key.parts.iter_mut() {
+                    part.set_text_supported(text_supp);
                 }
             }
         }