From 017861cd4bf173ebad81ae71feed0ec13c36ff46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franti=C5=A1ek=20Boh=C3=A1=C4=8Dek?=
 <fandabohacek@gmail.com>
Date: Sat, 24 Dec 2022 12:02:26 +0100
Subject: [PATCH] feat: add button events

---
 src/button.rs | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 72 insertions(+), 1 deletion(-)

diff --git a/src/button.rs b/src/button.rs
index cd85636..bb3cebf 100644
--- a/src/button.rs
+++ b/src/button.rs
@@ -8,14 +8,34 @@ pub enum ButtonState {
     Released // The button was just released
 }
 
+#[derive(Copy, Clone, PartialEq, Eq)]
+pub enum ButtonEvent {
+    Click,
+    LongClick,
+    LongClickContinuous,
+    DoubleClick,
+    None
+}
+
 const DEBOUNCECYCLES: u8 = 50;
 
+const PRESSED_FOR_MAX: u16 = 65000;
+const RELEASED_FOR_MAX: u16 = 65000;
+
+const PRESSED_FOR_LONG: u16 = 1000;
+const RELEASED_FOR_DOUBLE_CLICK: u16 = 1000;
+
 pub struct Button {
     input: Pin<mode::Input>,
     active_high: bool,
     last_active: bool,
     active: bool,
-    integrator: u8
+    integrator: u8,
+
+    pressed_for: u16,
+    released_for: u16,
+
+    last_event: ButtonEvent,
 }
 
 impl Button {
@@ -26,6 +46,9 @@ impl Button {
             last_active: false,
             active: false,
             integrator: 0,
+            pressed_for: 0,
+            released_for: 0,
+            last_event: ButtonEvent::None
         }
     }
 
@@ -43,7 +66,55 @@ impl Button {
             self.integrator += 1;
         }
 
+        let last_active = self.active;
         self.active = self.pressed();
+
+        if !last_active && self.active {
+            self.pressed_for = 0;
+        } else if last_active && !self.active {
+            self.released_for = 0;
+        }
+
+        if self.active {
+            if self.pressed_for < PRESSED_FOR_MAX {
+                self.pressed_for += 1;
+            }
+        }
+        else {
+            if self.released_for < RELEASED_FOR_MAX {
+                self.released_for += 1;
+            }
+        }
+
+        // just pressed and was released just for time it could be double click
+        // fire double click right away
+        // that is different to normal click. Normal clicks fire after release,
+        // double click fires right after the second press
+        if self.active && self.pressed_for == 1 && self.released_for < RELEASED_FOR_DOUBLE_CLICK {
+            self.last_event = ButtonEvent::DoubleClick;
+            self.pressed_for += 1;
+        }
+
+        // is a long click, fire event until released
+        if self.active && self.pressed_for == PRESSED_FOR_LONG {
+            self.last_event = ButtonEvent::LongClick;
+        }
+        else if self.active && self.pressed_for % PRESSED_FOR_LONG == 0 && self.last_event == ButtonEvent::None {
+            self.last_event = ButtonEvent::LongClickContinuous;
+        }
+
+        // was not long click and period for double click is over
+        if self.pressed_for < PRESSED_FOR_LONG && self.pressed_for > 1 && self.released_for == RELEASED_FOR_DOUBLE_CLICK {
+            self.last_event = ButtonEvent::Click;
+            self.released_for += 1;
+        }
+    }
+
+    pub fn event(&mut self) -> ButtonEvent {
+        let last_event = self.last_event;
+        self.last_event = ButtonEvent::None;
+
+        last_event
     }
 
     fn pressed(&mut self) -> bool{
-- 
2.48.1