feat(readarr): add the system handlers

SystemHandler owns the System tab: tab movement, the refresh key, and the
five keys that open the queued events, logs, tasks, and updates views. It
delegates every system detail block to SystemDetailsHandler, which scrolls
the log, task, queued event, and update views and drives the start task
confirmation prompt.

Both land together because SystemHandler::accepts covers the system detail
blocks that only SystemDetailsHandler implements, so landing the parent
alone would accept those blocks while doing nothing with them.

src/handlers/readarr_handlers/mod.rs

@@ -4,6 +4,7 @@ use crate::handlers::readarr_handlers::downloads::DownloadsHandler;
 use crate::handlers::readarr_handlers::history::HistoryHandler;
 use crate::handlers::readarr_handlers::library::LibraryHandler;
 use crate::handlers::readarr_handlers::root_folders::RootFoldersHandler;
+use crate::handlers::readarr_handlers::system::SystemHandler;
 use crate::models::Route;
 use crate::{
   app::App, event::Key, matches_key,
@@ -15,6 +16,7 @@ mod downloads;
 mod history;
 mod library;
 mod root_folders;
+mod system;
 
 #[cfg(test)]
 #[path = "readarr_handler_tests.rs"]
@@ -46,6 +48,9 @@ impl<'a, 'b> KeyEventHandler<'a, 'b, ActiveReadarrBlock> for ReadarrHandler<'a,
         RootFoldersHandler::new(self.key, self.app, self.active_readarr_block, self.context)
           .handle();
       }
+      _ if SystemHandler::accepts(self.active_readarr_block) => {
+        SystemHandler::new(self.key, self.app, self.active_readarr_block, self.context).handle();
+      }
       _ => self.handle_key_event(),
     }
   }

src/handlers/readarr_handlers/readarr_handler_tests.rs

@@ -246,4 +246,23 @@ mod tests {
       active_readarr_block
     );
   }
+
+  #[rstest]
+  fn test_delegates_system_blocks_to_system_handler(
+    #[values(
+      ActiveReadarrBlock::System,
+      ActiveReadarrBlock::SystemLogs,
+      ActiveReadarrBlock::SystemQueuedEvents,
+      ActiveReadarrBlock::SystemTasks,
+      ActiveReadarrBlock::SystemTaskStartConfirmPrompt,
+      ActiveReadarrBlock::SystemUpdates
+    )]
+    active_readarr_block: ActiveReadarrBlock,
+  ) {
+    test_handler_delegation!(
+      ReadarrHandler,
+      ActiveReadarrBlock::System,
+      active_readarr_block
+    );
+  }
 }

src/handlers/readarr_handlers/system/mod.rs

@@ -0,0 +1,135 @@
+use crate::app::App;
+use crate::event::Key;
+use crate::handlers::readarr_handlers::handle_change_tab_left_right_keys;
+use crate::handlers::readarr_handlers::system::system_details_handler::SystemDetailsHandler;
+use crate::handlers::{KeyEventHandler, handle_clear_errors};
+use crate::matches_key;
+use crate::models::servarr_data::readarr::readarr_data::ActiveReadarrBlock;
+use crate::models::{Route, Scrollable};
+
+mod system_details_handler;
+
+#[cfg(test)]
+#[path = "system_handler_tests.rs"]
+mod system_handler_tests;
+
+pub(super) struct SystemHandler<'a, 'b> {
+  key: Key,
+  app: &'a mut App<'b>,
+  active_readarr_block: ActiveReadarrBlock,
+  context: Option<ActiveReadarrBlock>,
+}
+
+impl<'a, 'b> KeyEventHandler<'a, 'b, ActiveReadarrBlock> for SystemHandler<'a, 'b> {
+  fn handle(&mut self) {
+    match self.active_readarr_block {
+      _ if SystemDetailsHandler::accepts(self.active_readarr_block) => {
+        SystemDetailsHandler::new(self.key, self.app, self.active_readarr_block, self.context)
+          .handle()
+      }
+      _ => self.handle_key_event(),
+    }
+  }
+
+  fn accepts(active_block: ActiveReadarrBlock) -> bool {
+    SystemDetailsHandler::accepts(active_block) || active_block == ActiveReadarrBlock::System
+  }
+
+  fn ignore_special_keys(&self) -> bool {
+    self.app.ignore_special_keys_for_textbox_input
+  }
+
+  fn new(
+    key: Key,
+    app: &'a mut App<'b>,
+    active_block: ActiveReadarrBlock,
+    context: Option<ActiveReadarrBlock>,
+  ) -> SystemHandler<'a, 'b> {
+    SystemHandler {
+      key,
+      app,
+      active_readarr_block: active_block,
+      context,
+    }
+  }
+
+  fn get_key(&self) -> Key {
+    self.key
+  }
+
+  fn is_ready(&self) -> bool {
+    !self.app.is_loading
+      && !self.app.data.readarr_data.logs.is_empty()
+      && !self.app.data.readarr_data.queued_events.is_empty()
+      && !self.app.data.readarr_data.tasks.is_empty()
+  }
+
+  fn handle_scroll_up(&mut self) {}
+
+  fn handle_scroll_down(&mut self) {}
+
+  fn handle_home(&mut self) {}
+
+  fn handle_end(&mut self) {}
+
+  fn handle_delete(&mut self) {}
+
+  fn handle_left_right_action(&mut self) {
+    if self.active_readarr_block == ActiveReadarrBlock::System {
+      handle_change_tab_left_right_keys(self.app, self.key);
+    }
+  }
+
+  fn handle_submit(&mut self) {}
+
+  fn handle_esc(&mut self) {
+    handle_clear_errors(self.app)
+  }
+
+  fn handle_char_key_event(&mut self) {
+    if self.active_readarr_block == ActiveReadarrBlock::System {
+      let key = self.key;
+      match self.key {
+        _ if matches_key!(refresh, key) => {
+          self.app.should_refresh = true;
+        }
+        _ if matches_key!(events, key) => {
+          self
+            .app
+            .push_navigation_stack(ActiveReadarrBlock::SystemQueuedEvents.into());
+        }
+        _ if matches_key!(logs, key) => {
+          self
+            .app
+            .push_navigation_stack(ActiveReadarrBlock::SystemLogs.into());
+          self
+            .app
+            .data
+            .readarr_data
+            .log_details
+            .set_items(self.app.data.readarr_data.logs.items.to_vec());
+          self.app.data.readarr_data.log_details.scroll_to_bottom();
+        }
+        _ if matches_key!(tasks, key) => {
+          self
+            .app
+            .push_navigation_stack(ActiveReadarrBlock::SystemTasks.into());
+        }
+        _ if matches_key!(update, key) => {
+          self
+            .app
+            .push_navigation_stack(ActiveReadarrBlock::SystemUpdates.into());
+        }
+        _ => (),
+      }
+    }
+  }
+
+  fn app_mut(&mut self) -> &mut App<'b> {
+    self.app
+  }
+
+  fn current_route(&self) -> Route {
+    self.app.get_current_route()
+  }
+}

src/handlers/readarr_handlers/system/system_details_handler.rs

@@ -0,0 +1,211 @@
+use crate::app::App;
+use crate::event::Key;
+use crate::handlers::{KeyEventHandler, handle_prompt_toggle};
+use crate::matches_key;
+use crate::models::readarr_models::ReadarrTaskName;
+use crate::models::servarr_data::readarr::readarr_data::{
+  ActiveReadarrBlock, SYSTEM_DETAILS_BLOCKS,
+};
+use crate::models::stateful_list::StatefulList;
+use crate::models::{Route, Scrollable};
+use crate::network::readarr_network::ReadarrEvent;
+
+#[cfg(test)]
+#[path = "system_details_handler_tests.rs"]
+mod system_details_handler_tests;
+
+pub(super) struct SystemDetailsHandler<'a, 'b> {
+  key: Key,
+  app: &'a mut App<'b>,
+  active_readarr_block: ActiveReadarrBlock,
+  _context: Option<ActiveReadarrBlock>,
+}
+
+impl SystemDetailsHandler<'_, '_> {
+  fn extract_task_name(&self) -> ReadarrTaskName {
+    self
+      .app
+      .data
+      .readarr_data
+      .tasks
+      .current_selection()
+      .task_name
+  }
+}
+
+impl<'a, 'b> KeyEventHandler<'a, 'b, ActiveReadarrBlock> for SystemDetailsHandler<'a, 'b> {
+  fn accepts(active_block: ActiveReadarrBlock) -> bool {
+    SYSTEM_DETAILS_BLOCKS.contains(&active_block)
+  }
+
+  fn ignore_special_keys(&self) -> bool {
+    self.app.ignore_special_keys_for_textbox_input
+  }
+
+  fn new(
+    key: Key,
+    app: &'a mut App<'b>,
+    active_block: ActiveReadarrBlock,
+    context: Option<ActiveReadarrBlock>,
+  ) -> SystemDetailsHandler<'a, 'b> {
+    SystemDetailsHandler {
+      key,
+      app,
+      active_readarr_block: active_block,
+      _context: context,
+    }
+  }
+
+  fn get_key(&self) -> Key {
+    self.key
+  }
+
+  fn is_ready(&self) -> bool {
+    !self.app.is_loading
+      && (!self.app.data.readarr_data.log_details.is_empty()
+        || !self.app.data.readarr_data.tasks.is_empty()
+        || !self.app.data.readarr_data.updates.is_empty())
+  }
+
+  fn handle_scroll_up(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => self.app.data.readarr_data.log_details.scroll_up(),
+      ActiveReadarrBlock::SystemTasks => self.app.data.readarr_data.tasks.scroll_up(),
+      ActiveReadarrBlock::SystemUpdates => self.app.data.readarr_data.updates.scroll_up(),
+      ActiveReadarrBlock::SystemQueuedEvents => {
+        self.app.data.readarr_data.queued_events.scroll_up()
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_scroll_down(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => self.app.data.readarr_data.log_details.scroll_down(),
+      ActiveReadarrBlock::SystemTasks => self.app.data.readarr_data.tasks.scroll_down(),
+      ActiveReadarrBlock::SystemUpdates => self.app.data.readarr_data.updates.scroll_down(),
+      ActiveReadarrBlock::SystemQueuedEvents => {
+        self.app.data.readarr_data.queued_events.scroll_down()
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_home(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => self.app.data.readarr_data.log_details.scroll_to_top(),
+      ActiveReadarrBlock::SystemTasks => self.app.data.readarr_data.tasks.scroll_to_top(),
+      ActiveReadarrBlock::SystemUpdates => self.app.data.readarr_data.updates.scroll_to_top(),
+      ActiveReadarrBlock::SystemQueuedEvents => {
+        self.app.data.readarr_data.queued_events.scroll_to_top()
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_end(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => self.app.data.readarr_data.log_details.scroll_to_bottom(),
+      ActiveReadarrBlock::SystemTasks => self.app.data.readarr_data.tasks.scroll_to_bottom(),
+      ActiveReadarrBlock::SystemUpdates => self.app.data.readarr_data.updates.scroll_to_bottom(),
+      ActiveReadarrBlock::SystemQueuedEvents => {
+        self.app.data.readarr_data.queued_events.scroll_to_bottom()
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_delete(&mut self) {}
+
+  fn handle_left_right_action(&mut self) {
+    let key = self.key;
+
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => match self.key {
+        _ if matches_key!(left, key) => {
+          self
+            .app
+            .data
+            .readarr_data
+            .log_details
+            .items
+            .iter()
+            .for_each(|log| log.scroll_right());
+        }
+        _ if matches_key!(right, key) => {
+          self
+            .app
+            .data
+            .readarr_data
+            .log_details
+            .items
+            .iter()
+            .for_each(|log| log.scroll_left());
+        }
+        _ => (),
+      },
+      ActiveReadarrBlock::SystemTaskStartConfirmPrompt => handle_prompt_toggle(self.app, self.key),
+      _ => (),
+    }
+  }
+
+  fn handle_submit(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemTasks => {
+        self
+          .app
+          .push_navigation_stack(ActiveReadarrBlock::SystemTaskStartConfirmPrompt.into());
+      }
+      ActiveReadarrBlock::SystemTaskStartConfirmPrompt => {
+        if self.app.data.readarr_data.prompt_confirm {
+          self.app.data.readarr_data.prompt_confirm_action =
+            Some(ReadarrEvent::StartTask(self.extract_task_name()));
+        }
+
+        self.app.pop_navigation_stack();
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_esc(&mut self) {
+    match self.active_readarr_block {
+      ActiveReadarrBlock::SystemLogs => {
+        self.app.data.readarr_data.log_details = StatefulList::default();
+        self.app.pop_navigation_stack()
+      }
+      ActiveReadarrBlock::SystemQueuedEvents
+      | ActiveReadarrBlock::SystemTasks
+      | ActiveReadarrBlock::SystemUpdates => self.app.pop_navigation_stack(),
+      ActiveReadarrBlock::SystemTaskStartConfirmPrompt => {
+        self.app.pop_navigation_stack();
+        self.app.data.readarr_data.prompt_confirm = false;
+      }
+      _ => (),
+    }
+  }
+
+  fn handle_char_key_event(&mut self) {
+    if SYSTEM_DETAILS_BLOCKS.contains(&self.active_readarr_block) && matches_key!(refresh, self.key)
+    {
+      self.app.should_refresh = true;
+    }
+
+    if self.active_readarr_block == ActiveReadarrBlock::SystemTaskStartConfirmPrompt
+      && matches_key!(confirm, self.key)
+    {
+      self.app.data.readarr_data.prompt_confirm = true;
+      self.app.data.readarr_data.prompt_confirm_action =
+        Some(ReadarrEvent::StartTask(self.extract_task_name()));
+      self.app.pop_navigation_stack();
+    }
+  }
+
+  fn app_mut(&mut self) -> &mut App<'b> {
+    self.app
+  }
+
+  fn current_route(&self) -> Route {
+    self.app.get_current_route()
+  }
+}

src/handlers/readarr_handlers/system/system_handler_tests.rs

@@ -0,0 +1,496 @@
+#[cfg(test)]
+mod tests {
+  use rstest::rstest;
+  use strum::IntoEnumIterator;
+
+  use crate::app::App;
+  use crate::app::key_binding::DEFAULT_KEYBINDINGS;
+  use crate::assert_navigation_pushed;
+  use crate::event::Key;
+  use crate::handlers::KeyEventHandler;
+  use crate::handlers::readarr_handlers::system::SystemHandler;
+  use crate::models::HorizontallyScrollableText;
+  use crate::models::readarr_models::{ReadarrTask, ReadarrTaskName};
+  use crate::models::servarr_data::readarr::readarr_data::{
+    ActiveReadarrBlock, SYSTEM_DETAILS_BLOCKS,
+  };
+  use crate::models::servarr_models::QueueEvent;
+  use crate::test_handler_delegation;
+
+  mod test_handle_left_right_action {
+    use pretty_assertions::assert_eq;
+
+    use super::*;
+    use crate::assert_navigation_pushed;
+
+    #[rstest]
+    fn test_system_tab_left(#[values(true, false)] is_loading: bool) {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      app.is_loading = is_loading;
+      app.data.readarr_data.main_tabs.set_index(6);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.left.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(
+        app.data.readarr_data.main_tabs.get_active_route(),
+        ActiveReadarrBlock::Indexers.into()
+      );
+      assert_navigation_pushed!(app, ActiveReadarrBlock::Indexers.into());
+    }
+
+    #[rstest]
+    fn test_system_tab_right(#[values(true, false)] is_loading: bool) {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      app.is_loading = is_loading;
+      app.data.readarr_data.main_tabs.set_index(6);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.right.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(
+        app.data.readarr_data.main_tabs.get_active_route(),
+        ActiveReadarrBlock::Authors.into()
+      );
+      assert_navigation_pushed!(app, ActiveReadarrBlock::Authors.into());
+    }
+  }
+
+  mod test_handle_esc {
+
+    use super::*;
+    use crate::assert_navigation_popped;
+
+    const ESC_KEY: Key = DEFAULT_KEYBINDINGS.esc.key;
+
+    #[rstest]
+    fn test_default_esc(#[values(true, false)] is_loading: bool) {
+      let mut app = App::test_default();
+      app.is_loading = is_loading;
+      app.error = "test error".to_owned().into();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+
+      SystemHandler::new(ESC_KEY, &mut app, ActiveReadarrBlock::System, None).handle();
+
+      assert_navigation_popped!(app, ActiveReadarrBlock::System.into());
+      assert_is_empty!(app.error.text);
+    }
+  }
+
+  mod test_handle_key_char {
+    use pretty_assertions::{assert_eq, assert_str_eq};
+
+    use super::*;
+
+    #[test]
+    fn test_update_system_key() {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.update.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_navigation_pushed!(app, ActiveReadarrBlock::SystemUpdates.into());
+    }
+
+    #[test]
+    fn test_update_system_key_no_op_if_not_ready() {
+      let mut app = App::test_default();
+      app.is_loading = true;
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.update.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+    }
+
+    #[test]
+    fn test_queued_events_key() {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.events.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_navigation_pushed!(app, ActiveReadarrBlock::SystemQueuedEvents.into());
+    }
+
+    #[test]
+    fn test_queued_events_key_no_op_if_not_ready() {
+      let mut app = App::test_default();
+      app.is_loading = true;
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.events.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+    }
+
+    #[test]
+    fn test_refresh_system_key() {
+      let mut app = App::test_default();
+      seed_system_data(&mut app);
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.refresh.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_navigation_pushed!(app, ActiveReadarrBlock::System.into());
+      assert!(app.should_refresh);
+    }
+
+    #[test]
+    fn test_refresh_system_key_no_op_if_not_ready() {
+      let mut app = App::test_default();
+      app.is_loading = true;
+      seed_system_data(&mut app);
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.refresh.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+      assert!(!app.should_refresh);
+    }
+
+    #[test]
+    fn test_logs_key() {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.logs.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_navigation_pushed!(app, ActiveReadarrBlock::SystemLogs.into());
+      assert_eq!(
+        app.data.readarr_data.log_details.items,
+        app.data.readarr_data.logs.items
+      );
+      assert_str_eq!(
+        app.data.readarr_data.log_details.current_selection().text,
+        "log line gamma"
+      );
+    }
+
+    #[test]
+    fn test_logs_key_no_op_when_not_ready() {
+      let mut app = App::test_default();
+      app.is_loading = true;
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.logs.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+      assert_is_empty!(app.data.readarr_data.log_details);
+    }
+
+    #[test]
+    fn test_tasks_key() {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.tasks.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_navigation_pushed!(app, ActiveReadarrBlock::SystemTasks.into());
+    }
+
+    #[test]
+    fn test_tasks_key_no_op_when_not_ready() {
+      let mut app = App::test_default();
+      app.is_loading = true;
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.tasks.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+    }
+
+    #[test]
+    fn test_unmapped_key_is_a_no_op() {
+      let mut app = App::test_default();
+      app.push_navigation_stack(ActiveReadarrBlock::System.into());
+      seed_system_data(&mut app);
+
+      SystemHandler::new(
+        DEFAULT_KEYBINDINGS.add.key,
+        &mut app,
+        ActiveReadarrBlock::System,
+        None,
+      )
+      .handle();
+
+      assert_eq!(app.get_current_route(), ActiveReadarrBlock::System.into());
+      assert!(!app.should_refresh);
+      assert_is_empty!(app.data.readarr_data.log_details);
+    }
+  }
+
+  #[rstest]
+  fn test_delegates_system_details_blocks_to_system_details_handler(
+    #[values(
+      ActiveReadarrBlock::SystemLogs,
+      ActiveReadarrBlock::SystemQueuedEvents,
+      ActiveReadarrBlock::SystemTasks,
+      ActiveReadarrBlock::SystemTaskStartConfirmPrompt,
+      ActiveReadarrBlock::SystemUpdates
+    )]
+    active_readarr_block: ActiveReadarrBlock,
+  ) {
+    test_handler_delegation!(
+      SystemHandler,
+      ActiveReadarrBlock::System,
+      active_readarr_block
+    );
+  }
+
+  #[test]
+  fn test_system_handler_accepts() {
+    let mut system_blocks = vec![ActiveReadarrBlock::System];
+    system_blocks.extend(SYSTEM_DETAILS_BLOCKS);
+
+    ActiveReadarrBlock::iter().for_each(|active_readarr_block| {
+      if system_blocks.contains(&active_readarr_block) {
+        assert!(SystemHandler::accepts(active_readarr_block));
+      } else {
+        assert!(!SystemHandler::accepts(active_readarr_block));
+      }
+    })
+  }
+
+  #[rstest]
+  fn test_system_handler_ignore_special_keys(
+    #[values(true, false)] ignore_special_keys_for_textbox_input: bool,
+  ) {
+    let mut app = App::test_default();
+    app.ignore_special_keys_for_textbox_input = ignore_special_keys_for_textbox_input;
+    let handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.esc.key,
+      &mut app,
+      ActiveReadarrBlock::default(),
+      None,
+    );
+
+    assert_eq!(
+      handler.ignore_special_keys(),
+      ignore_special_keys_for_textbox_input
+    );
+  }
+
+  #[test]
+  fn test_system_handler_is_not_ready_when_loading() {
+    let mut app = App::test_default();
+    app.push_navigation_stack(ActiveReadarrBlock::System.into());
+    app.is_loading = true;
+    seed_system_data(&mut app);
+
+    let system_handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.update.key,
+      &mut app,
+      ActiveReadarrBlock::System,
+      None,
+    );
+
+    assert!(!system_handler.is_ready());
+  }
+
+  #[test]
+  fn test_system_handler_is_not_ready_when_logs_is_empty() {
+    let mut app = App::test_default();
+    app.push_navigation_stack(ActiveReadarrBlock::System.into());
+    app.is_loading = false;
+    app.data.readarr_data.tasks.set_items(tasks_vec());
+    app
+      .data
+      .readarr_data
+      .queued_events
+      .set_items(queued_events_vec());
+
+    let system_handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.update.key,
+      &mut app,
+      ActiveReadarrBlock::System,
+      None,
+    );
+
+    assert!(!system_handler.is_ready());
+  }
+
+  #[test]
+  fn test_system_handler_is_not_ready_when_tasks_is_empty() {
+    let mut app = App::test_default();
+    app.push_navigation_stack(ActiveReadarrBlock::System.into());
+    app.is_loading = false;
+    app.data.readarr_data.logs.set_items(logs_vec());
+    app
+      .data
+      .readarr_data
+      .queued_events
+      .set_items(queued_events_vec());
+
+    let system_handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.update.key,
+      &mut app,
+      ActiveReadarrBlock::System,
+      None,
+    );
+
+    assert!(!system_handler.is_ready());
+  }
+
+  #[test]
+  fn test_system_handler_is_not_ready_when_queued_events_is_empty() {
+    let mut app = App::test_default();
+    app.push_navigation_stack(ActiveReadarrBlock::System.into());
+    app.is_loading = false;
+    app.data.readarr_data.logs.set_items(logs_vec());
+    app.data.readarr_data.tasks.set_items(tasks_vec());
+
+    let system_handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.update.key,
+      &mut app,
+      ActiveReadarrBlock::System,
+      None,
+    );
+
+    assert!(!system_handler.is_ready());
+  }
+
+  #[test]
+  fn test_system_handler_is_ready_when_all_required_tables_are_not_empty() {
+    let mut app = App::test_default();
+    app.push_navigation_stack(ActiveReadarrBlock::System.into());
+    app.is_loading = false;
+    seed_system_data(&mut app);
+
+    let system_handler = SystemHandler::new(
+      DEFAULT_KEYBINDINGS.update.key,
+      &mut app,
+      ActiveReadarrBlock::System,
+      None,
+    );
+
+    assert!(system_handler.is_ready());
+  }
+
+  fn seed_system_data(app: &mut App<'_>) {
+    app.data.readarr_data.logs.set_items(logs_vec());
+    app
+      .data
+      .readarr_data
+      .queued_events
+      .set_items(queued_events_vec());
+    app.data.readarr_data.tasks.set_items(tasks_vec());
+  }
+
+  fn logs_vec() -> Vec<HorizontallyScrollableText> {
+    vec![
+      HorizontallyScrollableText::from("log line alpha"),
+      HorizontallyScrollableText::from("log line beta"),
+      HorizontallyScrollableText::from("log line gamma"),
+    ]
+  }
+
+  fn queued_events_vec() -> Vec<QueueEvent> {
+    vec![
+      QueueEvent {
+        name: "queued event one".to_owned(),
+        ..QueueEvent::default()
+      },
+      QueueEvent {
+        name: "queued event two".to_owned(),
+        ..QueueEvent::default()
+      },
+    ]
+  }
+
+  fn tasks_vec() -> Vec<ReadarrTask> {
+    vec![
+      ReadarrTask {
+        name: "Backup task".to_owned(),
+        task_name: ReadarrTaskName::Backup,
+        ..ReadarrTask::default()
+      },
+      ReadarrTask {
+        name: "Rss sync task".to_owned(),
+        task_name: ReadarrTaskName::RssSync,
+        ..ReadarrTask::default()
+      },
+    ]
+  }
+}