panic if trying to enable a closed monitor

Cargo.lock

@@ -192,7 +192,7 @@ dependencies = [
 
 [[package]]
 name = "swayout"
-version = "1.2.0"
+version = "1.2.1"
 dependencies = [
  "kdl",
  "serde",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "swayout"
-version = "1.2.0"
+version = "1.2.1"
 edition = "2021"
 description = "A tool to configure sway outputs"
 authors = ["Stephen Byrne"]

src/lib.rs

@@ -133,9 +133,12 @@ pub fn print_layout_names() {
 /// Apply the specified layout.
 /// layout_name may be the name of a layout in the config, the name of a monitor,
 /// or the name of an output.
-pub fn apply_layout(layout_name: &String) {
+/// Return true of any outputs were enabled.
+/// Return false if there were no outputs to enable and thus nothing was done.
+pub fn apply_layout(layout_name: &String) -> bool {
     let config = get_config();
     let outputs = get_outputs();
+    let monitor_states = get_monitor_states(&config, &outputs);
 
     // Map of output name to config for all outputs to enable.
     // (All outputs not in this map will be disabled.)
@@ -147,55 +150,61 @@ pub fn apply_layout(layout_name: &String) {
         .iter()
         .find(|layout| &layout.name == layout_name)
     {
-        // The layout is defined in the rules.
+        // The layout is defined in the config.
         layout
             .outputs
             .iter()
             .for_each(|(monitor_name, output_config)| {
-                let monitor = &config
-                    .monitors
-                    .iter()
-                    .find(|monitor| &monitor.name == monitor_name)
-                    .unwrap();
+                let monitor_state = get_monitor_state_by_name(&monitor_states, &monitor_name)
+                    .unwrap_or_else(||panic!("Cannot find monitor '{}' for layout '{}'", monitor_name, layout_name));
+
+                if monitor_state.is_lid_closed {
+                    panic!("Monitor '{}' is closed", monitor_name);
+                }
 
                 // find the output for the monitor to get the output name.
                 let output_opt = outputs
                     .iter()
-                    .find(|output| monitor_matches_output(monitor, output));
+                    .find(|output| monitor_matches_output(monitor_state.monitor, output));
                 if let Some(output) = output_opt {
                     output_config_map.insert(&output.name, &output_config);
                 } else {
-                    panic!("Missing output for monitor {monitor_name}");
+                    panic!("Missing output for monitor '{monitor_name}'");
                 }
             });
     } else {
         // The layout is not defined in the rules.
         // See if it is a monitor name...
-        if let Some(monitor) = config
-            .monitors
-            .iter()
-            .find(|monitor| &monitor.name == layout_name)
-        {
+        if let Some(monitor_state) = get_monitor_state_by_name(&monitor_states, &layout_name) {
+            if monitor_state.is_lid_closed {
+                panic!("Monitor '{}' is closed", &monitor_state.monitor.name);
+            }
+
             // It is a monitor name. Find the matching output...
             if let Some(output) = outputs
                 .iter()
-                .find(|output| monitor_matches_output(monitor, output))
+                .find(|output| monitor_matches_output(monitor_state.monitor, output))
             {
                 output_config_map.insert(&output.name, &output.output_config);
             } else {
-                panic!("could not find output for monitor {layout_name}")
+                panic!("Could not find output for monitor '{layout_name}'")
             }
         } else {
             // See if it is an output name...
             if let Some(output) = outputs.iter().find(|output| &output.name == layout_name) {
                 output_config_map.insert(&output.name, &output.output_config);
             } else {
-                panic!("could not find layout, monitor, or output {layout_name}")
+                panic!("Could not find layout, monitor, or output '{layout_name}'")
             }
         }
     }
 
-    apply_outputs(&outputs, &output_config_map);
+    if ! output_config_map.is_empty() {
+        apply_outputs(&outputs, &output_config_map);
+        true
+    } else {
+        false
+    }
 }
 
 /// Apply the first automatic layout for which all outputs are available.
@@ -210,8 +219,11 @@ pub fn apply_automatic() -> Option<String> {
         .iter()
         .find(|layout| layout.automatic)
     {
-        apply_layout(&layout.name);
-        Some(String::from(&layout.name))
+        if apply_layout(&layout.name) {
+            Some(String::from(&layout.name))
+        } else {
+            None
+        }
     } else {
         None
     }

src/main.rs

@@ -15,7 +15,9 @@ fn main() {
                 process::exit(2)
             }
         } else {
-            swayout::apply_layout(&args[1]);
+            if ! swayout::apply_layout(&args[1]) {
+                process::exit(3)
+            }
         }
     } else {
         eprintln!("Usage: {} [layout]", args[0].as_str());

src/sway.rs

@@ -84,6 +84,10 @@ pub fn apply_outputs(all_outputs: &Vec<Output>, outputs: &HashMap<&String, &Outp
         }
     });
 
+    if enabled.is_empty() {
+        panic!("No enabled outputs!");
+    }
+
     let mut cmd = Command::new("swaymsg");
     enabled.iter().for_each(|(output_name, output_config)| {
         cmd.arg("output");