From b57763e68845f12832562d26bb7247af2f985541 Mon Sep 17 00:00:00 2001
From: veeso <christian.visintin1997@gmail.com>
Date: Wed, 3 Mar 2021 15:47:25 +0100
Subject: [PATCH] Msg instead of callbacks

---
 src/ui/layout/mod.rs   | 40 ++++++++++++++++++++++++++++++----------
 src/ui/layout/props.rs | 35 ++++-------------------------------
 2 files changed, 34 insertions(+), 41 deletions(-)

diff --git a/src/ui/layout/mod.rs b/src/ui/layout/mod.rs
index 422e1bd..62ca049 100644
--- a/src/ui/layout/mod.rs
+++ b/src/ui/layout/mod.rs
@@ -24,26 +24,44 @@
 */
 
 // Modules
+pub mod components;
 pub mod props;
 
 // locals
+use crate::ui::activities::Activity;
 use props::{Props, PropsBuilder};
 // ext
 use crossterm::event::Event as InputEvent;
 use tui::widgets::Widget;
 
+// -- Msg
+
+/// ## Msg
+/// 
+/// Msg is an enum returned by an `Update` or an `On`.
+/// Yep, I took inspiration from Elm.
+pub enum Msg {
+    OnSubmit(Payload),
+    None,
+}
+
+/// ## Payload
+/// 
+/// Payload describes the payload for a `Msg`
+pub enum Payload {
+    Text(String),
+    Number(isize),
+    Unumber(usize),
+    None
+}
+
 // -- States
 
 /// ## States
 ///
 /// States is a trait which defines the behaviours for the states model for the different component.
 /// A state contains internal values for each component.
-pub(crate) trait States {
-    /// ### update
-    ///
-    /// Create a new state from current one and new
-    fn update(&self, new: dyn States) -> dyn States;
-}
+pub(crate) trait States {}
 
 // -- Component
 
@@ -62,8 +80,9 @@ pub trait Component {
     ///
     /// Update component properties
     /// Properties should first be retrieved through `get_props` which creates a builder from
-    /// existing properties and then edited before calling update
-    fn update(&mut self, props: Option<Props>);
+    /// existing properties and then edited before calling update.
+    /// Returns a Msg to the view
+    fn update(&mut self, props: Props) -> Msg;
 
     /// ### get_props
     ///
@@ -74,8 +93,9 @@ pub trait Component {
 
     /// ### on
     ///
-    /// Handle input event and update internal states
-    fn on(&mut self, ev: InputEvent);
+    /// Handle input event and update internal states.
+    /// Returns a Msg to the view
+    fn on(&mut self, ev: InputEvent) -> Msg;
 
     // -- events
 
diff --git a/src/ui/layout/props.rs b/src/ui/layout/props.rs
index c4dd5fc..e7d66ff 100644
--- a/src/ui/layout/props.rs
+++ b/src/ui/layout/props.rs
@@ -23,14 +23,9 @@
 *
 */
 
-// locals
-use super::super::activities::Activity;
 // ext
 use tui::style::Color;
 
-// Callback types
-pub type OnSubmitCb = fn(&mut dyn Activity, Option<String>); // Activity, Value
-
 // -- Props
 
 /// ## Props
@@ -46,8 +41,6 @@ pub struct Props {
     pub italic: bool,      // Italic
     pub underlined: bool,  // Underlined
     pub texts: TextParts,  // text parts
-    // Callbacks
-    pub on_submit: Option<OnSubmitCb>,
 }
 
 impl Default for Props {
@@ -61,8 +54,6 @@ impl Default for Props {
             italic: false,
             underlined: false,
             texts: TextParts::default(),
-            // Callbacks
-            on_submit: None,
         }
     }
 }
@@ -80,8 +71,10 @@ impl PropsBuilder {
     /// ### from_props
     ///
     /// Create a props builder from existing properties
-    pub fn from_props(props: Props) -> Self {
-        PropsBuilder { props: Some(props) }
+    pub fn from_props(props: &Props) -> Self {
+        PropsBuilder {
+            props: Some(props.clone()),
+        }
     }
 
     /// ### build
@@ -160,16 +153,6 @@ impl PropsBuilder {
         }
         self
     }
-
-    /// ### on_submit
-    ///
-    /// Set on_submit callback for component
-    pub fn on_submit(&mut self, on_submit: OnSubmitCb) -> &mut Self {
-        if let Some(props) = self.props.as_mut() {
-            props.on_submit = Some(on_submit);
-        }
-        self
-    }
 }
 
 impl Default for PropsBuilder {
@@ -223,7 +206,6 @@ mod tests {
         assert_eq!(props.bold, false);
         assert_eq!(props.italic, false);
         assert_eq!(props.underlined, false);
-        assert!(props.on_submit.is_none());
         assert!(props.texts.title.is_none());
         assert!(props.texts.body.is_none());
     }
@@ -237,7 +219,6 @@ mod tests {
             .bold()
             .italic()
             .underlined()
-            .on_submit(on_submit_cb)
             .with_texts(TextParts::new(
                 Some(String::from("hello")),
                 Some(vec![String::from("hey")]),
@@ -269,7 +250,6 @@ mod tests {
             .bold()
             .italic()
             .underlined()
-            .on_submit(on_submit_cb)
             .with_texts(TextParts::new(
                 Some(String::from("hello")),
                 Some(vec![String::from("hey")]),
@@ -287,7 +267,6 @@ mod tests {
             .bold()
             .italic()
             .underlined()
-            .on_submit(on_submit_cb)
             .with_texts(TextParts::new(
                 Some(String::from("hello")),
                 Some(vec![String::from("hey")]),
@@ -321,10 +300,4 @@ mod tests {
         assert!(parts.title.is_none());
         assert!(parts.body.is_none());
     }
-
-    // Callbacks
-
-    fn on_submit_cb(_activity: &mut dyn Activity, val: Option<String>) {
-        println!("Val: {:?}", val);
-    }
 }