Create a validated text entry widget

I move the weight edit view into the validated text entry widget, and I
work on some of the unfortunate logic in the weight blur function. I've
left behind a lot of breadcrumbs for things that still need to be done.

fitnesstrax/app/src/components/day.rs

@@ -16,6 +16,7 @@ You should have received a copy of the GNU General Public License along with Fit
 
 // use chrono::NaiveDate;
 // use ft_core::TraxRecord;
+use crate::components::{ParseError, TextEntry};
 use chrono::{Local, NaiveDate};
 use dimensioned::si;
 use emseries::Record;
@@ -220,12 +221,23 @@ impl DayDetail {
     }
 }
 
+#[derive(Clone, Copy, PartialEq)]
+enum WeightViewMode {
+    View,
+    Edit,
+}
+
 pub struct WeightViewPrivate {
     date: RefCell<NaiveDate>,
     record: RefCell<Option<Weight>>,
     view: RefCell<gtk::Label>,
-    edit: RefCell<gtk::Entry>,
+    edit: RefCell<TextEntry<si::Kilogram<f64>>>,
     current: RefCell<gtk::Widget>,
+    mode: RefCell<WeightViewMode>,
+
+    // If I create a swappable component and don't make it a true GTK component, the way
+    // TextEntry<T> ended up not a true GTK component, on_edit_finished will not need to be a
+    // RefCell.
     on_edit_finished: RefCell<Box<dyn Fn(si::Kilogram<f64>)>>,
 }
 
@@ -236,7 +248,9 @@ impl Default for WeightViewPrivate {
             .halign(gtk::Align::Start)
             .can_focus(true)
             .build();
-        let edit = gtk::Entry::builder().halign(gtk::Align::Start).build();
+        let edit = TextEntry::<si::Kilogram<f64>>::new("weight", None, &|w: &str| {
+            w.parse::<f64>().map(|w| w * si::KG).map_err(|_| ParseError)
+        });
 
         let current = view.clone();
 
@@ -246,6 +260,7 @@ impl Default for WeightViewPrivate {
             view: RefCell::new(view),
             edit: RefCell::new(edit),
             current: RefCell::new(current.upcast()),
+            mode: RefCell::new(WeightViewMode::View),
             on_edit_finished: RefCell::new(Box::new(|_| {})),
         }
     }
@@ -307,16 +322,18 @@ impl WeightView {
                 view.set_label("No weight recorded");
             }
         }
+        *self.imp().mode.borrow_mut() = WeightViewMode::View;
         self.swap(view.clone().upcast());
     }
 
     fn edit(&self) {
         let edit = self.imp().edit.borrow();
         match *self.imp().record.borrow() {
-            Some(ref record) => edit.buffer().set_text(&format!("{:?}", record.weight)),
-            None => edit.buffer().set_text(""),
+            Some(ref record) => edit.set_value(Some(record.weight)),
+            None => edit.set_value(None),
         }
-        self.swap(edit.clone().upcast());
+        *self.imp().mode.borrow_mut() = WeightViewMode::Edit;
+        self.swap(edit.widget());
         edit.grab_focus();
     }
 
@@ -328,20 +345,44 @@ impl WeightView {
     }
 
     fn blur(&self) {
-        let edit = self.imp().edit.borrow();
-        if *self.imp().current.borrow() == *edit {
-            let w = edit.buffer().text().parse::<f64>().unwrap();
-            self.imp().on_edit_finished.borrow()(w * si::KG);
+        if *self.imp().mode.borrow() == WeightViewMode::Edit {
+            println!("on_blur");
+            let weight = self.imp().edit.borrow().value();
 
-            let mut record = self.imp().record.borrow_mut();
-            match *record {
-                Some(ref mut record) => record.weight = w * si::KG,
-                None => {
-                    *record = Some(Weight {
-                        date: self.imp().date.borrow().clone(),
-                        weight: w * si::KG,
-                    })
+            println!("new weight: {:?}", weight);
+
+            // This has really turned into rubbish
+            // on_edit_finished needs to accept a full record now.
+            // needs to be possible to delete a record if the value is None
+            // it's hard to be sure whether I need the full record object or if I need to update
+            // it. I probably don't. I think I need to borrow it and call on_edit_finished with an
+            // updated version of it.
+            // on_edit_finished still doesn't have a way to support a delete operation
+            let record = match (self.imp().record.borrow().clone(), weight) {
+                // update an existing record
+                (Some(record), Some(weight)) => Some(Weight {
+                    date: record.date,
+                    weight,
+                }),
+
+                // create a new record
+                (None, Some(weight)) => Some(Weight {
+                    date: self.imp().date.borrow().clone(),
+                    weight,
+                }),
+
+                // do nothing or delete an existing record
+                (_, None) => None,
+            };
+
+            println!("updated record: {:?}", record);
+
+            match record {
+                Some(record) => {
+                    self.imp().on_edit_finished.borrow()(record.weight);
+                    *self.imp().record.borrow_mut() = Some(record);
                 }
+                None => {}
             }
         }
         self.view();

fitnesstrax/app/src/components/mod.rs

@@ -17,6 +17,9 @@ You should have received a copy of the GNU General Public License along with Fit
 mod day;
 pub use day::{DayDetail, DaySummary};
 
+mod text_entry;
+pub use text_entry::{ParseError, TextEntry};
+
 use glib::Object;
 use gtk::{prelude::*, subclass::prelude::*};
 use std::{cell::RefCell, path::PathBuf, rc::Rc};

fitnesstrax/app/src/components/text_entry.rs

@@ -0,0 +1,73 @@
+/*
+Copyright 2023, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of FitnessTrax.
+
+FitnessTrax is free software: you can redistribute it and/or modify it under the terms of the GNU
+General Public License as published by the Free Software Foundation, either version 3 of the
+License, or (at your option) any later version.
+
+FitnessTrax is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
+even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with FitnessTrax. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+use gtk::prelude::*;
+use std::{cell::RefCell, rc::Rc};
+
+pub struct ParseError;
+
+#[derive(Clone)]
+pub struct TextEntry<T: Clone> {
+    value: Rc<RefCell<Option<T>>>,
+    widget: gtk::Entry,
+}
+
+impl<T: Clone> TextEntry<T> {
+    pub fn new(
+        placeholder: &str,
+        value: Option<T>,
+        validator: &'static dyn Fn(&str) -> Result<T, ParseError>,
+    ) -> Self {
+        let widget = gtk::Entry::builder().placeholder_text(placeholder).build();
+
+        let s = Self {
+            value: Rc::new(RefCell::new(value)),
+            widget,
+        };
+
+        s.widget.buffer().connect_text_notify({
+            let s = s.clone();
+            move |buffer| {
+                if buffer.text().is_empty() {
+                    *s.value.borrow_mut() = None;
+                }
+                match validator(buffer.text().as_str()) {
+                    Ok(v) => *s.value.borrow_mut() = Some(v),
+                    // need to change the border to provide a visual indicator of an error
+                    Err(_) => {}
+                }
+            }
+        });
+
+        s
+    }
+
+    pub fn value(&self) -> Option<T> {
+        self.value.borrow().clone()
+    }
+
+    pub fn set_value(&self, value: Option<T>) {
+        *self.value.borrow_mut() = value;
+    }
+
+    pub fn grab_focus(&self) {
+        self.widget.grab_focus();
+    }
+
+    pub fn widget(&self) -> gtk::Widget {
+        self.widget.clone().upcast::<gtk::Widget>()
+    }
+}