tools/publish/src/widget/navigation_area.rs

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

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();
                }
            }
            _ => {}
        }
    }
}