Refactor local var logic + add default vars

crates/eww/src/app.rs

@@ -90,6 +90,39 @@ impl WindowInitiator {
     ) -> Self {
         WindowInitiator { config_name, pos, size, monitor, anchor, args }
     }
+
+    pub fn get_local_window_variables(&self, id: &str, window_def: &WindowDefinition) -> Result<HashMap<VarName, DynVal>> {
+        let mut local_variables: HashMap<VarName, DynVal> = HashMap::new();
+
+        local_variables.insert(VarName::from("id"), DynVal::from(id));
+        if self.monitor.is_some() {
+            local_variables.insert(VarName::from("screen"), DynVal::from(self.monitor.unwrap()));
+        }
+
+        local_variables.extend(self.args.clone().into_iter());
+
+        for attr in &window_def.expected_args {
+            let name = VarName::from(attr.name.clone());
+            if !local_variables.contains_key(&name) {
+                if attr.optional {
+                    local_variables.insert(name, DynVal::from(String::new()));
+                } else {
+                    return Err(anyhow!("Error, {} was required when creating {} but was not given", attr.name, self.config_name));
+                }
+            }
+        }
+
+        if local_variables.len() != window_def.expected_args.len() {
+            let expected_args: HashSet<&String> = window_def.expected_args.iter().map(|x| &x.name.0).collect();
+            let unexpected_vars: Vec<VarName> = local_variables
+                .iter()
+                .filter_map(|(n,_)| if !expected_args.contains(&n.0) { Some(n.clone()) } else { None })
+                .collect();
+            return Err(anyhow!("{} were unexpectedly defined when creating window {}", unexpected_vars.join(","), self.config_name));
+        }
+
+        Ok(local_variables)
+    }
 }
 
 #[derive(Debug, Clone)]
@@ -356,28 +389,7 @@ impl App {
             window_def.geometry =
                 window_def.geometry.map(|x| x.override_if_given(initiator.anchor, initiator.pos, initiator.size));
 
-            // We will remove these parameters as we go through the required
-            let mut local_variables: HashMap<VarName, DynVal> = initiator.args.clone().into_iter().collect();
-
-            for attr in &window_def.expected_args {
-                let name = VarName::from(attr.name.clone());
-                if !local_variables.contains_key(&name) {
-                    if attr.optional {
-                        local_variables.insert(name, DynVal::from(String::new()));
-                    } else {
-                        return Err(anyhow!("Error, {} was required when creating {} but was not given", attr.name, window_name));
-                    }
-                }
-            }
-
-            if local_variables.len() != window_def.expected_args.len() {
-                let expected_args: HashSet<&String> = window_def.expected_args.iter().map(|x| &x.name.0).collect();
-                let unexpected_vars: Vec<VarName> = local_variables
-                    .iter()
-                    .filter_map(|(n,_)| if !expected_args.contains(&n.0) { Some(n.clone()) } else { None })
-                    .collect();
-                return Err(anyhow!("{} were unexpectedly defined when creating window {}", unexpected_vars.join(","), window_name));
-            }
+            let local_variables = initiator.get_local_window_variables(instance_id, &window_def)?;
 
             let root_index = self.scope_graph.borrow().root_index;