Actually be able to open the database

fitnesstrax/app/src/main.rs

@@ -17,7 +17,7 @@ You should have received a copy of the GNU General Public License along with Fit
 mod ui;
 
 use adw::prelude::*;
-use emseries::Series;
+use emseries::{EmseriesReadError, Series};
 use ft_core::TraxRecord;
 use gio::resources_lookup_data;
 use glib::Object;
@@ -36,6 +36,14 @@ const APP_ID_PROD: &str = "com.luminescent-dreams.fitnesstrax";
 
 const RESOURCE_BASE_PATH: &str = "/com/luminescent-dreams/fitnesstrax/";
 
+/// A set of events that can occur at the global application level. These events should represent
+/// significant state changes that should go through a central dispatcher.
+enum Events {
+    DatabaseChanged(Series<TraxRecord>),
+}
+// Note that I have not yet figured out the communication channel or how the central dispatcher
+// should work. There's a dance between the App and the AppWindow that I haven't figured out yet.
+
 /// The real, headless application. This is where all of the logic will reside.
 #[derive(Clone)]
 struct App {
@@ -50,6 +58,34 @@ impl App {
     }
 }
 
+pub struct PlaceholderViewPrivate {}
+
+#[glib::object_subclass]
+impl ObjectSubclass for PlaceholderViewPrivate {
+    const NAME: &'static str = "PlaceholderView";
+    type Type = PlaceholderView;
+    type ParentType = gtk::Box;
+
+    fn new() -> Self {
+        Self {}
+    }
+}
+
+impl ObjectImpl for PlaceholderViewPrivate {}
+impl WidgetImpl for PlaceholderViewPrivate {}
+impl BoxImpl for PlaceholderViewPrivate {}
+
+glib::wrapper! {
+    pub struct PlaceholderView(ObjectSubclass<PlaceholderViewPrivate>) @extends gtk::Box, gtk::Widget;
+}
+
+impl PlaceholderView {
+    pub fn new() -> Self {
+        let s: Self = Object::builder().build();
+        s
+    }
+}
+
 /// This is the view to show if the application has not yet been configured. It will walk the user
 /// through the most critical setup steps so that we can move on to the other views in the app.
 pub struct WelcomeViewPrivate {}
@@ -74,7 +110,7 @@ glib::wrapper! {
 }
 
 impl WelcomeView {
-    pub fn new<F>(on_save: F) -> Self
+    pub fn new<F>(on_save: Box<F>) -> Self
     where
         F: Fn(PathBuf) + 'static,
     {
@@ -111,7 +147,7 @@ impl WelcomeView {
         content.append(&gtk::Label::new(Some("Welcome to FitnessTrax. The application has not yet been configured, so I will walk you through that. Let's start out by selecting your database.")));
         content.append(&db_row);
 
-        let on_save = Box::new(on_save);
+        let on_save = on_save;
         save_button.connect_clicked({
             move |_| {
                 if let Some(path) = db_row.path() {
@@ -166,11 +202,12 @@ impl HistoricalView {
 
 /// The application window, or the main window, is the main user interface for the app. Almost
 /// everything occurs here.
+#[derive(Clone)]
 struct AppWindow {
     app: App,
     window: adw::ApplicationWindow,
     layout: gtk::Box,
-    current_view: RefCell<gtk::Widget>,
+    current_view: Rc<RefCell<gtk::Widget>>,
 }
 
 impl AppWindow {
@@ -187,12 +224,6 @@ impl AppWindow {
             .height_request(600)
             .build();
 
-        let current_view = if app.database.read().unwrap().is_none() {
-            WelcomeView::new(&|_| {}).upcast()
-        } else {
-            HistoricalView::new().upcast()
-        };
-
         let stylesheet = String::from_utf8(
             resources_lookup_data(
                 &format!("{}style.css", RESOURCE_BASE_PATH),
@@ -216,18 +247,77 @@ impl AppWindow {
         let layout = gtk::Box::builder()
             .orientation(gtk::Orientation::Vertical)
             .build();
+
+        let initial_view = PlaceholderView::new();
+
         layout.append(&header);
-        layout.append(&current_view);
+        layout.append(&initial_view);
 
         window.set_content(Some(&layout));
         window.present();
 
         let s = Self {
-            app,
+            app: app.clone(),
             window,
             layout,
-            current_view: RefCell::new(current_view),
+            current_view: Rc::new(RefCell::new(initial_view.upcast())),
         };
+
+        let initial_view = if app.database.read().unwrap().is_none() {
+            WelcomeView::new({
+                let app = app.clone();
+                let s = s.clone();
+                Box::new(move |path: PathBuf| {
+                    // The user has selected a path. Perhaps the path is new, perhaps it already
+                    // exists.
+                    //
+                    // If the file exists already, attempt to read it. Fail if that doesn't work.
+                    // A should show to the user something that indicates that the file exists but is
+                    // not already a database.
+                    //
+                    // If the file does not exist, create a new one. Again, show the user an error if
+                    // some kind of error occurs.
+                    if path.exists() {
+                        let db = Series::open(&path);
+                        match db {
+                            Ok(db) => {
+                                *app.database.write().unwrap() = Some(db);
+                                s.change_view(HistoricalView::new().upcast());
+                            }
+                            Err(EmseriesReadError::UUIDParseError(_)) => {
+                                println!("Invalid UUID detected in the file")
+                            }
+                            Err(EmseriesReadError::JSONParseError(_)) => {
+                                println!("The file cannot be parsed and may not be a database")
+                            }
+                            Err(EmseriesReadError::IOError(err)) => {
+                                println!("The file cannot be read: {}", err)
+                            }
+                        }
+                    } else {
+                        let db = Series::open(&path);
+                        match db {
+                            Ok(db) => {
+                                *app.database.write().unwrap() = Some(db);
+                                s.change_view(HistoricalView::new().upcast());
+                            }
+                            Err(EmseriesReadError::IOError(err)) => {
+                                println!("The file cannot be read: {}", err)
+                            }
+                            _ => unreachable!(
+                                "other error types should not be possible when creating a new DB"
+                            ),
+                        }
+                    }
+                })
+            })
+            .upcast()
+        } else {
+            HistoricalView::new().upcast()
+        };
+
+        s.change_view(initial_view);
+
         s
     }