use crate::prelude::*;
use std::time::{Duration, Instant};
use winit::dpi::{LogicalPosition, LogicalSize};

pub struct Selector;

impl<State: HasEvents, W: Widget + 'static> WidgetAttr<State, W> for Selector
where
    State::State: HasDefaultUiState,
{
    type Input = WidgetRef<TextEdit>;

    fn run(state: &mut State, container: WidgetRef<W>, id: Self::Input) {
        state.register_event(container, CursorSense::click_or_drag(), move |ctx| {
            let region = ctx.ui().window_region(&id).unwrap();
            let id_pos = region.top_left;
            let container_pos = ctx.state.ui().window_region(&container).unwrap().top_left;
            let pos = ctx.data.pos + container_pos - id_pos;
            let size = region.size();
            select(ctx.state, id, pos, size, ctx.data.sense.is_dragging());
        });
    }
}

pub struct Selectable;

impl<State: HasEvents> WidgetAttr<State, TextEdit> for Selectable
where
    State::State: HasDefaultUiState,
{
    type Input = ();

    fn run(state: &mut State, id: WidgetRef<TextEdit>, _: Self::Input) {
        state.register_event(id, CursorSense::click_or_drag(), move |ctx| {
            select(
                ctx.state,
                id,
                ctx.data.pos,
                ctx.data.size,
                ctx.data.sense.is_dragging(),
            );
        });
    }
}

fn select(
    state: &mut impl HasDefaultUiState,
    id: WidgetRef<TextEdit>,
    pos: Vec2,
    size: Vec2,
    dragging: bool,
) {
    let (ui, state) = HasDefaultUiState::ui_with_state(state);
    let now = Instant::now();
    let recent = (now - state.last_click) < Duration::from_millis(300);
    state.last_click = now;
    id.edit(ui).select(pos, size, dragging, recent);
    if let Some(region) = ui.window_region(&id) {
        state.window.set_ime_allowed(true);
        state.window.set_ime_cursor_area(
            LogicalPosition::<f32>::from(region.top_left.tuple()),
            LogicalSize::<f32>::from(region.size().tuple()),
        );
    }
    state.focus = Some(id);
}