feature: Beginnings of in-app config (#231)

Initial refactorings and additions to support in-app config.

- Refactor our current options logic to support in-app configs.  That is, we can write to a config file with our changes now.
- The default action when creating a new config file is to leave it blank. (TBD and for now, not sure on this one)
- Previously, we would set everything in a config file on startup; now we need to read from the config TOML struct whenever.
- `C` keybind is now occupied for configs.
- `no_write` option to never write to a config file.

6 files changed, 69 insertions, 4 deletions

diff --git a/src/canvas/dialogs/help_dialog.rs b/src/canvas/dialogs/help_dialog.rs
index 2b148f16..fe0f1c52 100644
--- a/src/canvas/dialogs/help_dialog.rs
+++ b/src/canvas/dialogs/help_dialog.rs
@@ -1,5 +1,6 @@
 use unicode_width::UnicodeWidthStr;
 
+use crate::{app::App, canvas::Painter, constants};
 use tui::{
     backend::Backend,
     layout::{Alignment, Rect},
@@ -7,8 +8,6 @@ use tui::{
     widgets::{Block, Borders, Paragraph},
 };
 
-use crate::{app::App, canvas::Painter, constants};
-
 const HELP_BASE: &str = " Help ── Esc to close ";
 
 pub trait HelpDialog {
@@ -17,6 +16,7 @@ pub trait HelpDialog {
     );
 }
 
+// TODO: [REFACTOR] Make generic dialog boxes to build off of instead?
 impl HelpDialog for Painter {
     fn draw_help_dialog<B: Backend>(
         &self, f: &mut Frame<'_, B>, app_state: &mut App, draw_loc: Rect,
diff --git a/src/canvas/screens.rs b/src/canvas/screens.rs
new file mode 100644
index 00000000..e17aa573
--- /dev/null
+++ b/src/canvas/screens.rs
@@ -0,0 +1,3 @@
+pub mod config_screen;
+
+pub use config_screen::*;
diff --git a/src/canvas/screens/config_screen.rs b/src/canvas/screens/config_screen.rs
new file mode 100644
index 00000000..6aa22493
--- /dev/null
+++ b/src/canvas/screens/config_screen.rs
@@ -0,0 +1,57 @@
+use crate::{app::App, canvas::Painter, constants};
+use tui::{
+    backend::Backend,
+    layout::Constraint,
+    layout::Direction,
+    layout::Layout,
+    layout::{Alignment, Rect},
+    terminal::Frame,
+    widgets::{Block, Borders, Paragraph},
+};
+
+pub trait ConfigScreen {
+    fn draw_config_screen<B: Backend>(
+        &self, f: &mut Frame<'_, B>, app_state: &mut App, draw_loc: Rect,
+    );
+}
+
+impl ConfigScreen for Painter {
+    fn draw_config_screen<B: Backend>(
+        &self, f: &mut Frame<'_, B>, app_state: &mut App, draw_loc: Rect,
+    ) {
+        let config_block = Block::default()
+            .title(&" Config ")
+            .title_style(self.colours.border_style)
+            .style(self.colours.border_style)
+            .borders(Borders::ALL)
+            .border_style(self.colours.border_style);
+
+        f.render_widget(config_block, draw_loc);
+
+        // let margined_draw_locs = Layout::default()
+        //     .margin(2)
+        //     .direction(Direction::Horizontal)
+        //     .constraints(
+        //         [
+        //             Constraint::Percentage(33),
+        //             Constraint::Percentage(34),
+        //             Constraint::Percentage(33),
+        //         ]
+        //         .as_ref(),
+        //     )
+        //     .split(draw_loc)
+        //     .into_iter()
+        //     .map(|loc| {
+        //         // Required to properly margin in *between* the rectangles.
+        //         Layout::default()
+        //             .horizontal_margin(1)
+        //             .constraints([Constraint::Percentage(100)].as_ref())
+        //             .split(loc)[0]
+        //     })
+        //     .collect::<Vec<Rect>>();
+
+        // for dl in margined_draw_locs {
+        //     f.render_widget(Block::default().borders(Borders::ALL), dl);
+        // }
+    }
+}
diff --git a/src/canvas/widgets/battery_display.rs b/src/canvas/widgets/battery_display.rs
index 3e4ca3e9..e50ed515 100644
--- a/src/canvas/widgets/battery_display.rs
+++ b/src/canvas/widgets/battery_display.rs
@@ -223,7 +223,7 @@ impl BatteryDisplayWidget for Painter {
                     .block(Block::default())
                     .divider(tui::symbols::line::VERTICAL)
                     .style(self.colours.text_style)
-                    .highlight_style(self.colours.currently_selected_text_style)
+                    .highlight_style(self.colours.currently_selected_text_style) //FIXME: [HIGHLIGHT] THIS IS BROKEN ON TUI's SIDE, override this with your own style...
                     .select(battery_widget_state.currently_selected_battery_index),
                 tab_draw_loc,
             );
diff --git a/src/canvas/widgets/mem_graph.rs b/src/canvas/widgets/mem_graph.rs
index 7accfa55..bdc0b0b7 100644
--- a/src/canvas/widgets/mem_graph.rs
+++ b/src/canvas/widgets/mem_graph.rs
@@ -78,6 +78,7 @@ impl MemGraphWidget for Painter {
                     .graph_type(tui::widgets::GraphType::Line),
             );
 
+            // FIXME: [SWAP] Hide this if denominator is 0...
             let swap_label = format!(
                 "SWP:{}{}",
                 app_state.canvas_data.swap_label_percent, app_state.canvas_data.swap_label_frac
diff --git a/src/canvas/widgets/process_table.rs b/src/canvas/widgets/process_table.rs
index 9adb318a..89a27ba9 100644
--- a/src/canvas/widgets/process_table.rs
+++ b/src/canvas/widgets/process_table.rs
@@ -413,7 +413,7 @@ impl ProcessTableWidget for Painter {
                     }
                 });
 
-                // TODO: gotop's "x out of y" thing is really nice to help keep track of the scroll position.
+                // TODO: gotop's "x out of y" thing is really nice to help keep track of the scroll position.  Add to everything?
                 f.render_stateful_widget(
                     Table::new(process_headers.iter(), process_rows)
                         .block(process_block)
@@ -531,6 +531,8 @@ impl ProcessTableWidget for Painter {
             let query = proc_widget_state.get_current_search_query().as_str();
             let grapheme_indices = UnicodeSegmentation::grapheme_indices(query, true);
 
+            // TODO: [CURSOR] blank cursor if not selected
+            // TODO: [CURSOR] blinking cursor?
             let query_with_cursor = build_query(
                 is_on_widget,
                 grapheme_indices,
@@ -579,6 +581,8 @@ impl ProcessTableWidget for Painter {
                 self.colours.text_style
             };
 
+            // FIXME: [MOUSE] Mouse support for these in search
+            // FIXME: [MOVEMENT] Movement support for these in search
             let option_text = vec![
                 Text::raw("\n"),
                 Text::styled(