use std::{cell::RefCell, rc::Rc};

use gpui::{
    AnyWindowHandle, AppContext as _, Context, IntoElement, Modifiers, ParentElement as _, Render,
    Styled as _, TestAppContext, VisualTestContext, Window, div,
};
use gpui_native_core::clipboard::{COPIED_DURATION, ClipboardButton};
use gpui_native_theme::Theme;

const VALUE: &str = "https://example.com/repo.git";

struct Harness {
    copies: Rc<RefCell<usize>>,
    disabled: bool,
}

impl Render for Harness {
    fn render(&mut self, _window: &mut Window, _cx: &mut Context<Self>) -> impl IntoElement {
        let copies = self.copies.clone();
        div().size_full().flex().flex_col().child(
            ClipboardButton::new("test-clipboard", VALUE)
                .disabled(self.disabled)
                .on_copied(move |_| *copies.borrow_mut() += 1),
        )
    }
}

/// A maximized window whose button stretches across the top control row, so
/// `point(px(60.), px(14.))` always lands on it.
fn clipboard_window(
    disabled: bool,
) -> (
    TestAppContext,
    VisualTestContext,
    AnyWindowHandle,
    Rc<RefCell<usize>>,
) {
    let mut cx = TestAppContext::single();
    cx.update(Theme::init);
    let copies = Rc::new(RefCell::new(0));
    let harness_copies = copies.clone();
    let window = cx.add_window(move |_, _| Harness {
        copies: harness_copies,
        disabled,
    });
    let window = window.into();
    cx.update_window(window, |_, window, cx| {
        window.draw(cx).clear(cx);
    })
    .unwrap();
    let visual = VisualTestContext::from_window(window, &cx);
    (cx, visual, window, copies)
}

fn draw(visual: &mut VisualTestContext, window: AnyWindowHandle) {
    visual
        .update_window(window, |_, window, cx| {
            window.draw(cx).clear(cx);
        })
        .unwrap();
}

fn clipboard_text(visual: &mut VisualTestContext) -> String {
    visual.update(|_window, cx| {
        cx.read_from_clipboard()
            .and_then(|item| item.text())
            .unwrap_or_default()
    })
}

fn click(visual: &mut VisualTestContext) {
    let selector = if visual.debug_bounds("clipboard").is_some() {
        "clipboard"
    } else {
        "clipboard-copied"
    };
    let bounds = visual
        .debug_bounds(selector)
        .expect("clipboard button should be rendered");
    visual.simulate_click(bounds.center(), Modifiers::default());
}

#[test]
fn click_copies_the_value_and_fires_on_copied() {
    let (_cx, mut visual, _window, copies) = clipboard_window(false);
    click(&mut visual);
    assert_eq!(clipboard_text(&mut visual), VALUE);
    assert_eq!(*copies.borrow(), 1);
}

#[test]
fn disabled_button_does_not_copy() {
    let (_cx, mut visual, _window, copies) = clipboard_window(true);
    click(&mut visual);
    assert_eq!(clipboard_text(&mut visual), "");
    assert_eq!(*copies.borrow(), 0);
}

#[test]
fn copied_confirmation_shows_then_reverts() {
    let (cx, mut visual, window, _copies) = clipboard_window(false);
    click(&mut visual);
    draw(&mut visual, window);
    assert!(
        visual.debug_bounds("clipboard-copied").is_some(),
        "the check mark state should render right after the click"
    );
    assert!(visual.debug_bounds("clipboard").is_none());

    cx.executor().advance_clock(COPIED_DURATION);
    visual.run_until_parked();
    draw(&mut visual, window);
    assert!(
        visual.debug_bounds("clipboard").is_some(),
        "the copy icon should return once the confirmation window passes"
    );
    assert!(visual.debug_bounds("clipboard-copied").is_none());
}

#[test]
fn a_second_click_within_the_window_keeps_the_confirmation_up() {
    let (cx, mut visual, window, _copies) = clipboard_window(false);
    click(&mut visual);
    cx.executor().advance_clock(COPIED_DURATION / 2);
    click(&mut visual);
    cx.executor().advance_clock(COPIED_DURATION / 2);
    visual.run_until_parked();
    draw(&mut visual, window);
    assert!(
        visual.debug_bounds("clipboard-copied").is_some(),
        "the first click's stale revert must not clear the second click's confirmation"
    );

    cx.executor().advance_clock(COPIED_DURATION);
    visual.run_until_parked();
    draw(&mut visual, window);
    assert!(visual.debug_bounds("clipboard").is_some());
}