Create side panel & global popup

Create a side panel UI element for desktop with three buttons for:
adding a column, settings, and account management. The account
management button is temporary pending a better design. It is the only
one that is interactable at the moment. When the user clicks it, the
global popup window will be shown and the AccountManagementView will be
presented on the window. The user can click on the X on the top right of
the window to close it.

Signed-off-by: kernelkind <kernelkind@gmail.com>
Signed-off-by: William Casarin <jb55@jb55.com>

src/ui/global_popup.rs

@@ -0,0 +1,127 @@
+use egui::{Align2, CentralPanel, RichText, Vec2, Window};
+
+use crate::Damus;
+
+use super::{
+    persist_state::{PERSISTED_GLOBAL_POPUP, PERSISTED_SIDE_PANEL},
+    AccountManagementView, View,
+};
+
+#[derive(Clone, Copy, Debug)]
+pub enum GlobalPopupType {
+    AccountManagement,
+}
+
+static ACCOUNT_MANAGEMENT_TITLE: &str = "Account Management";
+
+impl GlobalPopupType {
+    pub fn title(&self) -> &'static str {
+        match self {
+            Self::AccountManagement => ACCOUNT_MANAGEMENT_TITLE,
+        }
+    }
+}
+
+pub trait FromApp<'a> {
+    fn from_app(app: &'a mut crate::Damus) -> Self
+    where
+        Self: Sized;
+}
+
+fn title(title_str: &'static str) -> RichText {
+    RichText::new(title_str).size(24.0)
+}
+
+fn overlay_window<'a>(
+    open: &'a mut bool,
+    window_size: Vec2,
+    title_str: &'static str,
+) -> Window<'a> {
+    egui::Window::new(title(title_str))
+        .anchor(Align2::CENTER_CENTER, [0.0, 0.0])
+        .collapsible(false)
+        .auto_sized()
+        .movable(false)
+        .open(open)
+        .default_size(window_size)
+}
+
+static MARGIN: Vec2 = Vec2 { x: 100.0, y: 100.0 };
+
+pub struct DesktopGlobalPopup<'a> {
+    app: &'a mut Damus,
+}
+
+impl<'a> View for DesktopGlobalPopup<'a> {
+    fn ui(&mut self, ui: &mut egui::Ui) {
+        DesktopGlobalPopup::global_popup(self.app, ui.ctx())
+    }
+}
+
+impl<'a> DesktopGlobalPopup<'a> {
+    pub fn new(app: &'a mut Damus) -> Self {
+        DesktopGlobalPopup { app }
+    }
+    pub fn global_popup(app: &mut Damus, ctx: &egui::Context) {
+        CentralPanel::default().show(ctx, |ui| {
+            let available_size = ui.available_size();
+            let window_size = available_size - MARGIN;
+
+            if let Some(popup) = PERSISTED_SIDE_PANEL.get_state(ctx) {
+                let mut show_global_popup = PERSISTED_GLOBAL_POPUP.get_state(ctx);
+                if show_global_popup {
+                    overlay_window(&mut show_global_popup, window_size, popup.title()).show(
+                        ctx,
+                        |ui| {
+                            match popup {
+                                GlobalPopupType::AccountManagement => {
+                                    AccountManagementView::from_app(app).ui(ui)
+                                }
+                            };
+                        },
+                    );
+
+                    // user could have closed the window, set the new state in egui memory
+                    PERSISTED_GLOBAL_POPUP.set_state(ctx, show_global_popup);
+                }
+            }
+        });
+    }
+}
+
+mod preview {
+    use crate::{
+        ui::{DesktopSidePanel, Preview, View},
+        Damus,
+    };
+
+    use super::DesktopGlobalPopup;
+
+    pub struct GlobalPopupPreview {
+        app: Damus,
+    }
+
+    impl<'a> Preview for DesktopGlobalPopup<'a> {
+        type Prev = GlobalPopupPreview;
+
+        fn preview() -> Self::Prev {
+            GlobalPopupPreview::new()
+        }
+    }
+
+    impl GlobalPopupPreview {
+        fn new() -> Self {
+            GlobalPopupPreview {
+                app: Damus::mock("."),
+            }
+        }
+    }
+
+    impl View for GlobalPopupPreview {
+        fn ui(&mut self, ui: &mut egui::Ui) {
+            let mut panel = DesktopSidePanel::new(ui.ctx());
+            DesktopSidePanel::panel().show(ui.ctx(), |ui| panel.ui(ui));
+            DesktopGlobalPopup::new(&mut self.app).ui(ui);
+        }
+    }
+}