Layout View

src/ui/layout/view.rs

@@ -24,7 +24,7 @@
 */
 
 // imports
-use super::{Component, Msg, Props};
+use super::{Component, InputEvent, Msg, Payload, Props, PropsBuilder};
 // ext
 use std::collections::HashMap;
 
@@ -32,21 +32,20 @@ use std::collections::HashMap;
 ///
 /// View is the wrapper and manager for all the components.
 /// A View is a container for all the components in a certain layout.
-/// It is possible to have ligatures between elements, which causes for example a component a to lose focus in favour of b if a certain key is pressed.
 /// Each View can have only one focused component.
 pub struct View {
     components: HashMap<String, Box<dyn Component>>, // all the components in the view
     focus: Option<String>,                           // Current active component
-    focus_stack: Vec<String>,                        // Focus stack; used to give focus in case the current element loses focus
+    focus_stack: Vec<String>, // Focus stack; used to give focus in case the current element loses focus
 }
 
 // -- view
 
 impl View {
-    /// ### new
+    /// ### init
     ///
-    /// Instantiates a new `View`
-    pub fn new() -> Self {
+    /// Initialize a new `View`
+    pub fn init() -> Self {
         View {
             components: HashMap::new(),
             focus: None,
@@ -54,15 +53,86 @@ impl View {
         }
     }
 
+    // -- mount / umount
+
+    /// ### mount
+    ///
+    /// Mount a new component in the view
+    pub fn mount(&mut self, id: &str, component: Box<dyn Component>) {
+        self.components.insert(id.to_string(), component);
+    }
+
+    /// ### umount
+    ///
+    /// Umount a component from the view
+    pub fn umount(&mut self, id: &str) {
+        self.components.remove(id);
+    }
+
+    // -- props
+
+    /// ### get_props
+    ///
+    /// Get component properties
+    pub fn get_props(&self, id: &str) -> Option<PropsBuilder> {
+        match self.components.get(id) {
+            None => None,
+            Some(cmp) => Some(cmp.get_props()),
+        }
+    }
+
+    /// update
+    ///
+    /// Update component properties
+    /// Returns `None` if component doesn't exist
+    pub fn update<'a>(&mut self, id: &'a str, props: Props) -> Option<(&'a str, Msg)> {
+        match self.components.get_mut(id) {
+            None => None,
+            Some(cmp) => Some((id, cmp.update(props))),
+        }
+    }
+
+    // -- state
+
+    /// ### get_value
+    ///
+    /// Get component value
+    pub fn get_value(&self, id: &str) -> Option<Payload> {
+        match self.components.get(id) {
+            None => None,
+            Some(cmp) => Some(cmp.get_value()),
+        }
+    }
+
+    // -- events
+
+    /// ### on
+    ///
+    /// Handle event for the focused component (if any)
+    /// Returns `None` if no component is focused
+    pub fn on(&mut self, ev: InputEvent) -> Option<(&str, Msg)> {
+        match self.focus.as_ref() {
+            None => None,
+            Some(id) => match self.components.get_mut(id) {
+                None => None,
+                Some(cmp) => Some((id, cmp.on(ev))),
+            },
+        }
+    }
+
     // -- private
 
     /// ### blur
     ///
-    /// Blur selected element and push it into the stack;
-    /// Last element in stack becomes active
-    fn blur(&mut self) {
+    /// Blur selected element AND DON'T PUSH CURRENT ACTIVE ELEMENT INTO THE STACK
+    /// Last element in stack becomes active and is removed from the stack
+    pub fn blur(&mut self) {
         if let Some(component) = self.focus.take() {
-            // Set last element as active
+            // Blur component
+            if let Some(cmp) = self.components.get_mut(component.as_str()) {
+                cmp.blur();
+            }
+            // Set last element in the stack as active
             let mut new: Option<String> = None;
             if let Some(last) = self.focus_stack.last() {
                 // Set focus to last element
@@ -73,21 +143,27 @@ impl View {
             if let Some(new) = new {
                 self.pop_from_stack(new.as_str());
             }
-            // Finally previous active component to stack
-            self.push_to_stack(&component);
         }
     }
 
     /// ### active
     ///
     /// Active provided element
-    fn active(&mut self, component: &str) {
-        // If there is an element active; call blur
-        if self.focus.is_some() {
-            self.blur();
+    /// Current active component, if any, GETS PUSHED to the STACK
+    pub fn active(&mut self, component: &str) {
+        // Active component if exists
+        if let Some(cmp) = self.components.get_mut(component) {
+            // Active component
+            cmp.active();
+            // Put current focus if any, into the stack
+            if let Some(active_component) = self.focus.take() {
+                self.push_to_stack(active_component.as_str());
+            }
+            // Give focus to component
+            self.focus = Some(component.to_string());
+            // Remove new component from the stack
+            self.pop_from_stack(component);
         }
-        // Set focus
-        self.focus = Some(component.to_string());
     }
 
     /// ### push_to_stack
@@ -105,3 +181,201 @@ impl View {
         self.focus_stack.retain(|c| c.as_str() != name);
     }
 }
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    use super::super::components::input::Input;
+    use super::super::components::text::Text;
+    use super::super::props::{PropValue, TextParts, TextSpan};
+
+    use crossterm::event::{KeyCode, KeyEvent};
+
+    #[test]
+    fn test_ui_layout_view_init() {
+        let view: View = View::init();
+        // Verify view
+        assert_eq!(view.components.len(), 0);
+        assert!(view.focus.is_none());
+        assert_eq!(view.focus_stack.len(), 0);
+    }
+
+    #[test]
+    fn test_ui_layout_view_mount_umount() {
+        let mut view: View = View::init();
+        // Mount component
+        let input: &str = "INPUT";
+        view.mount(input, make_component_input());
+        // Verify is mounted
+        assert!(view.components.get(input).is_some());
+        // Mount another
+        let text: &str = "TEXT";
+        view.mount(text, make_component_text());
+        assert!(view.components.get(text).is_some());
+        assert_eq!(view.components.len(), 2);
+        // Verify you cannot have duplicates
+        view.mount(input, make_component_input());
+        assert_eq!(view.components.len(), 2); // length should still be 2
+                                              // Umount
+        view.umount(text);
+        assert_eq!(view.components.len(), 1);
+        assert!(view.components.get(text).is_none());
+    }
+
+    #[test]
+    fn test_ui_layout_view_focus() {
+        let mut view: View = View::init();
+        // Prepare ids
+        let input1: &str = "INPUT_1";
+        let input2: &str = "INPUT_2";
+        let input3: &str = "INPUT_3";
+        let text1: &str = "TEXT_1";
+        let text2: &str = "TEXT_2";
+        // Mount components
+        view.mount(input1, make_component_input());
+        view.mount(input2, make_component_input());
+        view.mount(input3, make_component_input());
+        view.mount(text1, make_component_text());
+        view.mount(text2, make_component_text());
+        // Verify focus
+        assert!(view.focus.is_none());
+        assert_eq!(view.focus_stack.len(), 0);
+        // Blur when nothing is selected
+        view.blur();
+        assert!(view.focus.is_none());
+        assert_eq!(view.focus_stack.len(), 0);
+        // Active unexisting component
+        view.active("UNEXISTING-COMPONENT");
+        assert!(view.focus.is_none());
+        assert_eq!(view.focus_stack.len(), 0);
+        // Give focus to a component
+        view.active(input1);
+        // Check focus
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input1);
+        assert_eq!(view.focus_stack.len(), 0); // NOTE: stack is empty until a focus gets blurred
+                                               // Active a new component
+        view.active(input2);
+        // Now focus should be on input2, but input 1 should be in the focus stack
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input2);
+        assert_eq!(view.focus_stack.len(), 1);
+        assert_eq!(view.focus_stack[0].as_str(), input1);
+        // Active input 3
+        view.active(input3);
+        // now focus should be hold by input3, and stack should have len 2
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input3);
+        assert_eq!(view.focus_stack.len(), 2);
+        assert_eq!(view.focus_stack[0].as_str(), input1);
+        assert_eq!(view.focus_stack[1].as_str(), input2);
+        // blur
+        view.blur();
+        // Focus should now be hold by input2; input 3 should NOT be in the stack
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input2);
+        assert_eq!(view.focus_stack.len(), 1);
+        assert_eq!(view.focus_stack[0].as_str(), input1);
+        // Active twice
+        view.active(input2);
+        // Nothing should have changed
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input2);
+        assert_eq!(view.focus_stack.len(), 1);
+        assert_eq!(view.focus_stack[0].as_str(), input1);
+        // Blur again; stack should become empty, whether focus should then be hold by input 1
+        view.blur();
+        assert_eq!(view.focus.as_ref().unwrap().as_str(), input1);
+        assert_eq!(view.focus_stack.len(), 0);
+        // Blur again; now everything should be none
+        view.blur();
+        assert!(view.focus.is_none());
+        assert_eq!(view.focus_stack.len(), 0);
+    }
+
+    #[test]
+    fn test_ui_layout_view_update() {
+        let mut view: View = View::init();
+        // Prepare ids
+        let text: &str = "TEXT";
+        // Mount text
+        view.mount(text, make_component_text());
+        // Get properties and update
+        let props: Props = view.get_props(text).unwrap().build();
+        // Verify bold is false
+        assert_eq!(props.bold, false);
+        // Update properties and set bold to true
+        let mut builder = view.get_props(text).unwrap();
+        let (id, msg) = view.update(text, builder.bold().build()).unwrap();
+        // Verify return values
+        assert_eq!(id, text);
+        assert_eq!(msg, Msg::None);
+        // Verify bold is now true
+        let props: Props = view.get_props(text).unwrap().build();
+        // Verify bold is false
+        assert_eq!(props.bold, true);
+        // Get properties for unexisting component
+        assert!(view.update("foobar", props).is_none());
+    }
+
+    #[test]
+    fn test_ui_layout_view_on() {
+        let mut view: View = View::init();
+        // Prepare ids
+        let text: &str = "TEXT";
+        let input: &str = "INPUT";
+        // Mount
+        view.mount(text, make_component_text());
+        view.mount(input, make_component_input());
+        // Verify current value
+        assert_eq!(view.get_value(text).unwrap(), Payload::None); // Text value is Nothing
+        assert_eq!(
+            view.get_value(input).unwrap(),
+            Payload::Text(String::from("text"))
+        ); // Defined in `make_component_input`
+           // Handle events WITHOUT ANY ACTIVE ELEMENT
+        assert!(view
+            .on(InputEvent::Key(KeyEvent::from(KeyCode::Enter)))
+            .is_none());
+        // Active input
+        view.active(input);
+        // Now handle events on input
+        // Try char
+        assert_eq!(
+            view.on(InputEvent::Key(KeyEvent::from(KeyCode::Char('1'))))
+                .unwrap(),
+            (input, Msg::None)
+        );
+        // Verify new value
+        assert_eq!(
+            view.get_value(input).unwrap(),
+            Payload::Text(String::from("text1"))
+        );
+        // Verify enter
+        assert_eq!(
+            view.on(InputEvent::Key(KeyEvent::from(KeyCode::Enter)))
+                .unwrap(),
+            (input, Msg::OnSubmit(Payload::Text(String::from("text1"))))
+        );
+    }
+
+    /// ### make_component
+    ///
+    /// Make a new component; we'll use Input, which uses a rich set of events
+    fn make_component_input() -> Box<dyn Component> {
+        Box::new(Input::new(
+            PropsBuilder::default()
+                .with_texts(TextParts::new(Some(String::from("mytext")), None))
+                .with_value(PropValue::Str(String::from("text")))
+                .build(),
+        ))
+    }
+
+    fn make_component_text() -> Box<dyn Component> {
+        Box::new(Text::new(
+            PropsBuilder::default()
+                .with_texts(TextParts::new(
+                    None,
+                    Some(vec![TextSpan::from("Sample text")]),
+                ))
+                .build(),
+        ))
+    }
+}