feat: add visual feedback for printing

Print button is disabled while a job is being sent and a spinner shows
in the footer. On success a transient 'Sent to printer' confirmation is
displayed for a few seconds; on failure the error message stays in the
footer instead of replacing the document view.

src/main.rs

@@ -16,6 +16,7 @@ use std::ffi::OsStr;
 use std::hash::{Hash, Hasher};
 use std::path::{Path, PathBuf};
 use std::process::Command;
+use std::time::Duration;
 
 #[derive(Parser, Debug)]
 #[command(
@@ -115,9 +116,17 @@ enum Message {
     PrintTask {
         result: Result<(), String>,
     },
+    ClearPrintStatus,
     KeyChar(Key),
 }
 
+#[derive(Clone, Debug, PartialEq, Eq)]
+enum PrintStatus {
+    Sending,
+    Sent,
+    Failed(String),
+}
+
 struct NoctuaApp {
     core: Core,
     documents: Vec<Document>,
@@ -125,6 +134,7 @@ struct NoctuaApp {
     zoom: f32,
     modifiers: keyboard::Modifiers,
     printing: bool,
+    print_status: Option<PrintStatus>,
 }
 
 fn main() -> cosmic::iced::Result {
@@ -188,6 +198,7 @@ impl Application for NoctuaApp {
             zoom: 1.0,
             modifiers: keyboard::Modifiers::default(),
             printing: false,
+            print_status: None,
         };
 
         app.refresh_title();
@@ -284,71 +295,35 @@ impl Application for NoctuaApp {
                 }
             }
             // Print handling
-            Message::Print => {
+            Message::Print => return self.start_print(),
-                if self.printing {
-                    return Task::none();
-                }
-
-                let document = match self.current_document() {
-                    Some(doc) => doc,
-                    None => return Task::none(),
-                };
-                let path = document.path.clone();
-                let kind = document.kind;
-
-                self.printing = true;
-
-                return Task::perform(
-                    tokio::task::spawn_blocking(move || print_document_sync(&path, kind)),
-                    |result| {
-                        let inner = result
-                            .map_err(|e| format!("Spawn error: {e}"))
-                            .and_then(|r| r);
-                        cosmic::Action::App(Message::PrintTask { result: inner })
-                    },
-                );
-            }
             Message::KeyChar(key) => {
                 // Handle Ctrl+P shortcut for printing
                 if self.modifiers.control() && key == Key::Character("p".into()) {
-                    if self.printing {
+                    return self.start_print();
-                        return Task::none();
-                    }
-
-                    let document = match self.current_document() {
-                        Some(doc) => doc,
-                        None => return Task::none(),
-                    };
-                    let path = document.path.clone();
-                    let kind = document.kind;
-
-                    self.printing = true;
-
-                    return Task::perform(
-                        tokio::task::spawn_blocking(move || print_document_sync(&path, kind)),
-                        |result| {
-                            let inner = result
-                                .map_err(|e| format!("Spawn error: {e}"))
-                                .and_then(|r| r);
-                            cosmic::Action::App(Message::PrintTask { result: inner })
-                        },
-                    );
                 }
             }
             Message::PrintTask { result } => {
                 self.printing = false;
                 match result {
                     Ok(()) => {
-                        // Print succeeded – no visual feedback needed,
+                        self.print_status = Some(PrintStatus::Sent);
-                        // the document was sent to the printer.
+                        return Task::perform(
+                            tokio::task::spawn_blocking(|| {
+                                std::thread::sleep(Duration::from_secs(4));
+                            }),
+                            |_| cosmic::Action::App(Message::ClearPrintStatus),
+                        );
                     }
                     Err(err) => {
-                        if let Some(document) = self.current_document_mut() {
+                        self.print_status = Some(PrintStatus::Failed(err));
-                            document.error = Some(err);
-                        }
                     }
                 }
             }
+            Message::ClearPrintStatus => {
+                if matches!(self.print_status, Some(PrintStatus::Sent)) {
+                    self.print_status = None;
+                }
+            }
         }
 
         self.refresh_title();
@@ -447,8 +422,9 @@ impl Application for NoctuaApp {
             .push(widget::space::horizontal().width(Length::Fill))
             .push(
                 widget::button::standard("Print")
-                    .on_press(Message::Print),
+                    .on_press_maybe((!self.printing).then_some(Message::Print)),
             )
+            .push(print_status_view(self.print_status.as_ref()))
             .push(widget::text::body(page_label))
             .push(
                 widget::button::standard("Prev page")
@@ -511,6 +487,32 @@ impl NoctuaApp {
         self.core.set_header_title(title);
     }
 
+    fn start_print(&mut self) -> Task<Message> {
+        if self.printing {
+            return Task::none();
+        }
+
+        let document = match self.current_document() {
+            Some(doc) => doc,
+            None => return Task::none(),
+        };
+        let path = document.path.clone();
+        let kind = document.kind;
+
+        self.printing = true;
+        self.print_status = Some(PrintStatus::Sending);
+
+        Task::perform(
+            tokio::task::spawn_blocking(move || print_document_sync(&path, kind)),
+            |result| {
+                let inner = result
+                    .map_err(|e| format!("Spawn error: {e}"))
+                    .and_then(|r| r);
+                cosmic::Action::App(Message::PrintTask { result: inner })
+            },
+        )
+    }
+
     fn ensure_current_rendered(&mut self) -> Task<Message> {
         let render_task = {
             let Some(document) = self.current_document_mut() else {
@@ -634,6 +636,25 @@ fn empty_view<'a>(message: impl Into<String>) -> Element<'a, Message> {
         .into()
 }
 
+fn print_status_view(status: Option<&PrintStatus>) -> Element<'_, Message> {
+    match status {
+        Some(PrintStatus::Sending) => widget::progress_bar::indeterminate_circular()
+            .size(16.0)
+            .bar_height(2.0)
+            .into(),
+        Some(PrintStatus::Sent) => widget::text::body("Sent to printer")
+            .class(theme::Text::Accent)
+            .into(),
+        Some(PrintStatus::Failed(err)) => widget::text::body(format!("Print failed: {err}"))
+            .class(theme::Text::Custom(|t| cosmic::iced_widget::text::Style {
+                color: Some(t.cosmic().destructive_color().into()),
+                ..Default::default()
+            }))
+            .into(),
+        None => widget::space::horizontal().width(Length::Fixed(0.0)).into(),
+    }
+}
+
 fn scroll_delta_y(delta: mouse::ScrollDelta) -> Option<f32> {
     let y = match delta {
         mouse::ScrollDelta::Lines { y, .. } => y,