tools/publish/src/widget/navigation_area.rs

use iced::advanced::layout::{Limits, Node};
use iced::advanced::renderer::Style;
use iced::advanced::widget::{Operation, Tree};
use iced::advanced::{Layout, Shell, Widget, mouse, overlay, text};
use iced::mouse::Cursor;
use iced::widget::text_input::Catalog;
use iced::{Element, Event, Length, Rectangle, Size, Vector};

pub struct NavigationArea<'a, Message, Theme, Renderer>
where
    Theme: Catalog,
    Renderer: text::Renderer,
{
    content: Element<'a, Message, Theme, Renderer>,
    on_back_click: Option<Message>,
    on_forward_click: Option<Message>,
}

impl<'a, Message, Theme, Renderer> NavigationArea<'a, Message, Theme, Renderer>
where
    Message: Clone,
    Theme: Catalog,
    Renderer: text::Renderer,
{
    #[must_use]
    pub fn new(content: impl Into<Element<'a, Message, Theme, Renderer>>) -> Self {
        Self {
            content: content.into(),
            on_back_click: None,
            on_forward_click: None,
        }
    }

    #[must_use]
    pub fn on_back_click(mut self, message: Message) -> Self {
        self.on_back_click = Some(message);
        self
    }

    #[must_use]
    pub fn on_forward_click(mut self, message: Message) -> Self {
        self.on_forward_click = Some(message);
        self
    }
}

impl<'a, Message, Theme, Renderer> From<NavigationArea<'a, Message, Theme, Renderer>>
    for Element<'a, Message, Theme, Renderer>
where
    Message: Clone + 'a,
    Theme: Catalog + 'a,
    Renderer: text::Renderer + 'a,
{
    fn from(value: NavigationArea<'a, Message, Theme, Renderer>) -> Self {
        Element::new(value)
    }
}

pub fn navigation_area<'a, Message, Theme, Renderer>(
    content: impl Into<Element<'a, Message, Theme, Renderer>>,
) -> NavigationArea<'a, Message, Theme, Renderer>
where
    Message: Clone,
    Theme: Catalog,
    Renderer: text::Renderer,
{
    NavigationArea::new(content)
}

impl<Message, Theme, Renderer> Widget<Message, Theme, Renderer>
    for NavigationArea<'_, Message, Theme, Renderer>
where
    Message: Clone,
    Theme: Catalog,
    Renderer: text::Renderer,
{
    fn size(&self) -> Size<Length> {
        self.content.as_widget().size()
    }

    fn layout(&mut self, tree: &mut Tree, renderer: &Renderer, limits: &Limits) -> Node {
        self.content
            .as_widget_mut()
            .layout(&mut tree.children[0], renderer, limits)
    }

    fn draw(
        &self,
        tree: &Tree,
        renderer: &mut Renderer,
        theme: &Theme,
        style: &Style,
        layout: Layout<'_>,
        cursor: Cursor,
        viewport: &Rectangle,
    ) {
        self.content.as_widget().draw(
            &tree.children[0],
            renderer,
            theme,
            style,
            layout,
            cursor,
            viewport,
        );
    }

    fn diff(&mut self, tree: &mut Tree) {
        tree.diff_children(std::slice::from_mut(&mut self.content));
    }

    fn operate(
        &mut self,
        tree: &mut Tree,
        layout: Layout<'_>,
        renderer: &Renderer,
        operation: &mut dyn Operation,
    ) {
        self.content
            .as_widget_mut()
            .operate(&mut tree.children[0], layout, renderer, operation);
    }

    fn update(
        &mut self,
        tree: &mut Tree,
        event: &Event,
        layout: Layout<'_>,
        cursor: Cursor,
        renderer: &Renderer,
        shell: &mut Shell<'_, Message>,
        viewport: &Rectangle,
    ) {
        self.content.as_widget_mut().update(
            &mut tree.children[0],
            event,
            layout,
            cursor,
            renderer,
            shell,
            viewport,
        );

        if shell.is_event_captured() {
            return;
        }

        match event {
            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Back)) => {
                if let Some(on_back_click) = &self.on_back_click {
                    shell.publish(on_back_click.clone());
                    shell.capture_event();
                }
            }
            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Forward)) => {
                if let Some(on_forward_click) = &self.on_forward_click {
                    shell.publish(on_forward_click.clone());
                    shell.capture_event();
                }
            }
            _ => {}
        }
    }

    fn mouse_interaction(
        &self,
        tree: &Tree,
        layout: Layout<'_>,
        cursor: mouse::Cursor,
        viewport: &Rectangle,
        renderer: &Renderer,
    ) -> mouse::Interaction {
        self.content.as_widget().mouse_interaction(
            &tree.children[0],
            layout,
            cursor,
            viewport,
            renderer,
        )
    }

    fn overlay<'b>(
        &'b mut self,
        tree: &'b mut Tree,
        layout: Layout<'b>,
        renderer: &Renderer,
        viewport: &Rectangle,
        translation: Vector,
    ) -> Option<overlay::Element<'b, Message, Theme, Renderer>> {
        self.content.as_widget_mut().overlay(
            &mut tree.children[0],
            layout,
            renderer,
            viewport,
            translation,
        )
    }
}