use std::rc::Rc;

use gpui::prelude::FluentBuilder as _;
use gpui::{
    AnyElement, App, ClickEvent, ElementId, InteractiveElement, Interactivity, IntoElement,
    ParentElement, RenderOnce, SharedString, StatefulInteractiveElement as _, StyleRefinement,
    Styled, Window, div,
};
use theme::ActiveTheme;

use crate::{Selectable, StyledExt, h_flex, v_flex};

/// A single navigation row, such as an entry in a sidebar list.
#[derive(IntoElement)]
pub struct Nav {
    id: ElementId,
    interactivity: Interactivity,
    style: StyleRefinement,
    prefix: Option<AnyElement>,
    label: SharedString,
    suffix: Option<AnyElement>,
    selected: bool,
    clickable: bool,
    #[allow(clippy::type_complexity)]
    on_click: Option<Rc<dyn Fn(&ClickEvent, &mut Window, &mut App)>>,
}

impl Nav {
    pub fn new(id: impl Into<ElementId>) -> Self {
        let id = id.into();
        let mut interactivity = Interactivity::default();
        interactivity.element_id = Some(id.clone());

        Self {
            id,
            interactivity,
            style: StyleRefinement::default(),
            prefix: None,
            label: SharedString::default(),
            suffix: None,
            selected: false,
            clickable: false,
            on_click: None,
        }
    }

    /// Marks the row as clickable even when it has no `on_click` handler, so it
    /// still shows the hover affordance. Used by rows whose click opens a menu.
    pub fn clickable(mut self, clickable: bool) -> Self {
        self.clickable = clickable;
        self
    }

    /// Sets the element shown before the label, such as an avatar or icon.
    pub fn prefix(mut self, prefix: impl IntoElement) -> Self {
        self.prefix = Some(prefix.into_any_element());
        self
    }

    /// Sets the row's label.
    pub fn label(mut self, label: impl Into<SharedString>) -> Self {
        self.label = label.into();
        self
    }

    /// Sets the element shown after the label, such as a timestamp or badge.
    pub fn suffix(mut self, suffix: impl IntoElement) -> Self {
        self.suffix = Some(suffix.into_any_element());
        self
    }

    pub fn on_click(
        mut self,
        handler: impl Fn(&ClickEvent, &mut Window, &mut App) + 'static,
    ) -> Self {
        self.on_click = Some(Rc::new(handler));
        self
    }
}

impl Selectable for Nav {
    fn selected(mut self, selected: bool) -> Self {
        self.selected = selected;
        self
    }

    fn is_selected(&self) -> bool {
        self.selected
    }
}

impl InteractiveElement for Nav {
    fn interactivity(&mut self) -> &mut Interactivity {
        &mut self.interactivity
    }
}

impl Styled for Nav {
    fn style(&mut self) -> &mut StyleRefinement {
        &mut self.style
    }
}

impl RenderOnce for Nav {
    fn render(self, _window: &mut Window, cx: &mut App) -> impl IntoElement {
        let clickable = self.on_click.is_some() || self.clickable;

        v_flex().w_full().h_10().child(
            h_flex()
                .id(self.id)
                .h_9()
                .w_full()
                .px_1p5()
                .gap_1p5()
                .rounded(cx.theme().radius_lg)
                .when_some(self.prefix, |this, prefix| this.child(prefix))
                .child(
                    h_flex()
                        .gap_1()
                        .flex_1()
                        .min_w_0()
                        .child(div().flex_1().min_w_0().truncate().child(self.label))
                        .when_some(self.suffix, |this, suffix| {
                            this.child(div().flex_shrink_0().child(suffix))
                        }),
                )
                .when(clickable, |this| {
                    this.cursor_pointer()
                        .hover(|this| this.bg(cx.theme().ghost_element_hover))
                        .when(self.selected, |this| {
                            this.bg(cx.theme().ghost_element_active)
                        })
                })
                .when_some(self.on_click, |this, handler| {
                    this.on_click(move |event, window, cx| handler(event, window, cx))
                })
                .refine_style(&self.style),
        )
    }
}