From 1682b6c28fc7d0521c33f878f1a9c8cd2329d13d Mon Sep 17 00:00:00 2001
From: Dustin Carlino <dabreegster@gmail.com>
Date: Sun, 22 Mar 2020 15:20:46 -0700
Subject: [PATCH] trait-ify Button

---
 ezgui/src/managed.rs          |  38 +++----------
 ezgui/src/widgets/button.rs   | 103 +++++++++++++++++-----------------
 ezgui/src/widgets/checkbox.rs |   6 +-
 ezgui/src/widgets/dropdown.rs |   4 +-
 ezgui/src/widgets/mod.rs      |   3 +
 5 files changed, 70 insertions(+), 84 deletions(-)

diff --git a/ezgui/src/managed.rs b/ezgui/src/managed.rs
index 1758eda80c..a896026230 100644
--- a/ezgui/src/managed.rs
+++ b/ezgui/src/managed.rs
@@ -22,7 +22,6 @@ pub struct Widget {
 }
 
 enum WidgetType {
-    Btn(Button),
     Row(Vec<Widget>),
     Column(Vec<Widget>),
     Nothing,
@@ -247,7 +246,7 @@ impl Widget {
 
     pub(crate) fn btn(btn: Button) -> Widget {
         let action = btn.action.clone();
-        Widget::new(WidgetType::Btn(btn)).named(action)
+        Widget::new(WidgetType::Generic(Box::new(btn))).named(action)
     }
 
     pub fn slider(slider: Slider) -> Widget {
@@ -352,12 +351,6 @@ impl Widget {
 impl Widget {
     fn event(&mut self, ctx: &mut EventCtx, redo_layout: &mut bool) -> Option<Outcome> {
         match self.widget {
-            WidgetType::Btn(ref mut btn) => {
-                btn.event(ctx);
-                if btn.clicked() {
-                    return Some(Outcome::Clicked(btn.action.clone()));
-                }
-            }
             WidgetType::Row(ref mut widgets) | WidgetType::Column(ref mut widgets) => {
                 for w in widgets {
                     if let Some(o) = w.event(ctx, redo_layout) {
@@ -388,7 +381,6 @@ impl Widget {
         }
 
         match self.widget {
-            WidgetType::Btn(ref btn) => btn.draw(g),
             WidgetType::Row(ref widgets) | WidgetType::Column(ref widgets) => {
                 for w in widgets {
                     w.draw(g);
@@ -402,7 +394,6 @@ impl Widget {
     // Populate a flattened list of Nodes, matching the traversal order
     fn get_flexbox(&self, parent: Node, stretch: &mut Stretch, nodes: &mut Vec<Node>) {
         let dims = match self.widget {
-            WidgetType::Btn(ref widget) => widget.get_dims(),
             WidgetType::Row(ref widgets) => {
                 let mut style = Style {
                     flex_direction: FlexDirection::Row,
@@ -491,9 +482,6 @@ impl Widget {
         }
 
         match self.widget {
-            WidgetType::Btn(ref mut widget) => {
-                widget.set_pos(top_left);
-            }
             WidgetType::Row(ref mut widgets) => {
                 // layout() doesn't return absolute position; it's relative to the container.
                 for widget in widgets {
@@ -530,31 +518,23 @@ impl Widget {
 
     fn get_all_click_actions(&self, actions: &mut HashSet<String>) {
         match self.widget {
-            WidgetType::Btn(ref btn) => {
-                if actions.contains(&btn.action) {
-                    panic!(
-                        "Two buttons in one Composite both use action {}",
-                        btn.action
-                    );
-                }
-                actions.insert(btn.action.clone());
-            }
             WidgetType::Row(ref widgets) | WidgetType::Column(ref widgets) => {
                 for w in widgets {
                     w.get_all_click_actions(actions);
                 }
             }
             WidgetType::Nothing => unreachable!(),
-            // TODO Will need something
-            WidgetType::Generic(_) => {}
+            WidgetType::Generic(ref w) => w.get_all_click_actions(actions),
         }
     }
 
     pub fn is_btn(&self, name: &str) -> bool {
-        if let WidgetType::Btn(ref btn) = self.widget {
-            btn.action == name
-        } else {
-            false
+        match self.widget {
+            WidgetType::Generic(ref w) => w
+                .downcast_ref::<Button>()
+                .map(|btn| btn.action == name)
+                .unwrap_or(false),
+            _ => false,
         }
     }
 
@@ -597,7 +577,7 @@ impl Widget {
 
     pub(crate) fn take_btn(self) -> Button {
         match self.widget {
-            WidgetType::Btn(btn) => btn,
+            WidgetType::Generic(w) => *w.downcast::<Button>().ok().unwrap(),
             _ => unreachable!(),
         }
     }
diff --git a/ezgui/src/widgets/button.rs b/ezgui/src/widgets/button.rs
index 185be8c09b..695997acc5 100644
--- a/ezgui/src/widgets/button.rs
+++ b/ezgui/src/widgets/button.rs
@@ -1,8 +1,9 @@
 use crate::{
-    text, Color, Drawable, EventCtx, GeomBatch, GfxCtx, JustDraw, Line, MultiKey, RewriteColor,
-    ScreenDims, ScreenPt, Text, Widget, WidgetImpl,
+    text, Color, Drawable, EventCtx, GeomBatch, GfxCtx, JustDraw, Line, MultiKey, Outcome,
+    RewriteColor, ScreenDims, ScreenPt, ScreenRectangle, Text, Widget, WidgetImpl,
 };
 use geom::Polygon;
+use std::collections::HashSet;
 
 pub struct Button {
     pub action: String,
@@ -18,7 +19,6 @@ pub struct Button {
     hitbox: Polygon,
 
     hovering: bool,
-    clicked: bool,
 
     pub(crate) top_left: ScreenPt,
     dims: ScreenDims,
@@ -53,58 +53,11 @@ impl Button {
             hitbox,
 
             hovering: false,
-            clicked: false,
 
             top_left: ScreenPt::new(0.0, 0.0),
             dims,
         }
     }
-
-    pub(crate) fn event(&mut self, ctx: &mut EventCtx) {
-        if self.clicked {
-            panic!("Caller didn't consume button click");
-        }
-
-        if ctx.redo_mouseover() {
-            if let Some(pt) = ctx.canvas.get_cursor_in_screen_space() {
-                self.hovering = self
-                    .hitbox
-                    .translate(self.top_left.x, self.top_left.y)
-                    .contains_pt(pt.to_pt());
-            } else {
-                self.hovering = false;
-            }
-        }
-        if self.hovering && ctx.normal_left_click() {
-            self.clicked = true;
-            self.hovering = false;
-        }
-
-        if let Some(ref hotkey) = self.hotkey {
-            if ctx.input.new_was_pressed(hotkey) {
-                self.clicked = true;
-                self.hovering = false;
-            }
-        }
-    }
-
-    pub(crate) fn clicked(&mut self) -> bool {
-        if self.clicked {
-            self.clicked = false;
-            true
-        } else {
-            false
-        }
-    }
-
-    pub(crate) fn draw(&self, g: &mut GfxCtx) {
-        if self.hovering {
-            g.redraw_at(self.top_left, &self.draw_hovered);
-            g.draw_mouse_tooltip(self.tooltip.clone());
-        } else {
-            g.redraw_at(self.top_left, &self.draw_normal);
-        }
-    }
 }
 
 impl WidgetImpl for Button {
@@ -115,6 +68,56 @@ impl WidgetImpl for Button {
     fn set_pos(&mut self, top_left: ScreenPt) {
         self.top_left = top_left;
     }
+
+    fn event(
+        &mut self,
+        ctx: &mut EventCtx,
+        _rect: &ScreenRectangle,
+        _redo_layout: &mut bool,
+    ) -> Option<Outcome> {
+        if ctx.redo_mouseover() {
+            if let Some(pt) = ctx.canvas.get_cursor_in_screen_space() {
+                self.hovering = self
+                    .hitbox
+                    .translate(self.top_left.x, self.top_left.y)
+                    .contains_pt(pt.to_pt());
+            } else {
+                self.hovering = false;
+            }
+        }
+        if self.hovering && ctx.normal_left_click() {
+            self.hovering = false;
+            return Some(Outcome::Clicked(self.action.clone()));
+        }
+
+        if let Some(ref hotkey) = self.hotkey {
+            if ctx.input.new_was_pressed(hotkey) {
+                self.hovering = false;
+                return Some(Outcome::Clicked(self.action.clone()));
+            }
+        }
+
+        None
+    }
+
+    fn draw(&self, g: &mut GfxCtx) {
+        if self.hovering {
+            g.redraw_at(self.top_left, &self.draw_hovered);
+            g.draw_mouse_tooltip(self.tooltip.clone());
+        } else {
+            g.redraw_at(self.top_left, &self.draw_normal);
+        }
+    }
+
+    fn get_all_click_actions(&self, actions: &mut HashSet<String>) {
+        if actions.contains(&self.action) {
+            panic!(
+                "Two buttons in one Composite both use action {}",
+                self.action
+            );
+        }
+        actions.insert(self.action.clone());
+    }
 }
 
 pub struct Btn {}
diff --git a/ezgui/src/widgets/checkbox.rs b/ezgui/src/widgets/checkbox.rs
index ead98a65e8..5621b950c2 100644
--- a/ezgui/src/widgets/checkbox.rs
+++ b/ezgui/src/widgets/checkbox.rs
@@ -36,11 +36,11 @@ impl WidgetImpl for Checkbox {
     fn event(
         &mut self,
         ctx: &mut EventCtx,
-        _rect: &ScreenRectangle,
+        rect: &ScreenRectangle,
         redo_layout: &mut bool,
     ) -> Option<Outcome> {
-        self.btn.event(ctx);
-        if self.btn.clicked() {
+        // TODO Lying about the rectangle
+        if self.btn.event(ctx, rect, redo_layout).is_some() {
             std::mem::swap(&mut self.btn, &mut self.other_btn);
             self.btn.set_pos(self.other_btn.top_left);
             self.enabled = !self.enabled;
diff --git a/ezgui/src/widgets/dropdown.rs b/ezgui/src/widgets/dropdown.rs
index 6402d424f3..95e0ed8933 100644
--- a/ezgui/src/widgets/dropdown.rs
+++ b/ezgui/src/widgets/dropdown.rs
@@ -75,8 +75,8 @@ impl<T: 'static + Clone> WidgetImpl for Dropdown<T> {
                 }
             }
         } else {
-            self.btn.event(ctx);
-            if self.btn.clicked() {
+            // TODO Again lying about the rectangle
+            if self.btn.event(ctx, rect, redo_layout).is_some() {
                 // TODO set current idx in menu
                 // TODO Choice::map_value?
                 let mut menu = PopupMenu::new(
diff --git a/ezgui/src/widgets/mod.rs b/ezgui/src/widgets/mod.rs
index 361b412176..96e2b8b6c3 100644
--- a/ezgui/src/widgets/mod.rs
+++ b/ezgui/src/widgets/mod.rs
@@ -14,6 +14,7 @@ pub mod wizard;
 
 use crate::{EventCtx, GfxCtx, Outcome, ScreenDims, ScreenPt, ScreenRectangle};
 use ordered_float::NotNan;
+use std::collections::HashSet;
 
 pub trait WidgetImpl: downcast_rs::Downcast {
     fn get_dims(&self) -> ScreenDims;
@@ -29,6 +30,8 @@ pub trait WidgetImpl: downcast_rs::Downcast {
         None
     }
     fn draw(&self, _g: &mut GfxCtx) {}
+
+    fn get_all_click_actions(&self, _actions: &mut HashSet<String>) {}
 }
 
 downcast_rs::impl_downcast!(WidgetImpl);