use cascade::cascade;
use glib::clone;
use gtk4::{gdk, glib, prelude::*, subclass::prelude::*};
use std::cell::Cell;

use crate::deref_cell::DerefCell;
use crate::status_area::StatusArea;
use crate::time_button::TimeButton;
use crate::x;

#[derive(Default)]
pub struct PanelWindowInner {
    size: Cell<Option<(i32, i32)>>,
    monitor: DerefCell<gdk::Monitor>,
}

#[glib::object_subclass]
impl ObjectSubclass for PanelWindowInner {
    const NAME: &'static str = "S76PanelWindow";
    type ParentType = gtk4::Window;
    type Type = PanelWindow;
}

impl ObjectImpl for PanelWindowInner {
    fn constructed(&self, obj: &PanelWindow) {
        let box_ = cascade! {
            gtk4::CenterBox::new();
            ..set_start_widget(Some(&cascade! {
                gtk4::Box::new(gtk4::Orientation::Horizontal, 0);
                ..append(&gtk4::Button::with_label("Workspaces"));
                ..append(&gtk4::Button::with_label("Applications"));
            }));
            ..set_center_widget(Some(&TimeButton::new()));
            ..set_end_widget(Some(&StatusArea::new()));
        };

        cascade! {
            obj;
            ..set_decorated(false);
            ..set_child(Some(&box_));
        };
    }
}

impl WidgetImpl for PanelWindowInner {
    fn realize(&self, obj: &PanelWindow) {
        self.parent_realize(obj);

        let surface = obj.surface().unwrap();
        surface.connect_layout(clone!(@weak obj => move |_surface, width, height| {
            let size = Some((width, height));
            if obj.inner().size.replace(size) != size {
                obj.monitor_geometry_changed();
            }
        }));
    }

    fn show(&self, obj: &PanelWindow) {
        self.parent_show(obj);

        if let Some((display, surface)) = x::get_window_x11(obj) {
            unsafe {
                surface.set_skip_pager_hint(true);
                surface.set_skip_taskbar_hint(true);
                x::wm_state_add(&display, &surface, "_NET_WM_STATE_ABOVE");
                x::wm_state_add(&display, &surface, "_NET_WM_STATE_STICKY");
                x::change_property(
                    &display,
                    &surface,
                    "_NET_WM_ALLOWED_ACTIONS",
                    x::PropMode::Replace,
                    &[
                        x::Atom::new(&display, "_NET_WM_ACTION_CHANGE_DESKTOP").unwrap(),
                        x::Atom::new(&display, "_NET_WM_ACTION_ABOVE").unwrap(),
                        x::Atom::new(&display, "_NET_WM_ACTION_BELOW").unwrap(),
                    ],
                );
                x::change_property(
                    &display,
                    &surface,
                    "_NET_WM_WINDOW_TYPE",
                    x::PropMode::Replace,
                    &[x::Atom::new(&display, "_NET_WM_WINDOW_TYPE_DOCK").unwrap()],
                );
            }
        }

        self.monitor
            .connect_geometry_notify(clone!(@strong obj => move |_| {
                obj.monitor_geometry_changed();
            }));
        obj.monitor_geometry_changed();
    }
}

impl WindowImpl for PanelWindowInner {}

glib::wrapper! {
    pub struct PanelWindow(ObjectSubclass<PanelWindowInner>)
        @extends gtk4::Window, gtk4::Widget,
        @implements gtk4::Accessible, gtk4::Buildable, gtk4::ConstraintTarget, gtk4::Native, gtk4::Root, gtk4::ShortcutManager;
}

impl PanelWindow {
    pub fn new(monitor: gdk::Monitor) -> Self {
        let obj = glib::Object::new::<Self>(&[]).unwrap();

        monitor.connect_invalidate(clone!(@weak obj => move |_| obj.close()));

        obj.set_size_request(monitor.geometry().width, 0);
        obj.inner().monitor.set(monitor);

        obj
    }

    fn inner(&self) -> &PanelWindowInner {
        PanelWindowInner::from_instance(self)
    }

    fn monitor_geometry_changed(&self) {
        let geometry = self.inner().monitor.geometry();
        self.set_size_request(geometry.width, 0);

        let top = if let Some((_width, height)) = self.inner().size.get() {
            height as x::c_ulong
        } else {
            return;
        };

        if let Some((display, surface)) = x::get_window_x11(self) {
            let top_start_x = geometry.x as x::c_ulong;
            let top_end_x = top_start_x + geometry.width as x::c_ulong - 1;

            unsafe {
                x::set_position(&display, &surface, top_start_x as _, 0);

                x::change_property(
                    &display,
                    &surface,
                    "_NET_WM_STRUT_PARTIAL",
                    x::PropMode::Replace,
                    &[0, 0, top, 0, 0, 0, 0, 0, top_start_x, top_end_x, 0, 0],
                );
            }
        }
    }
}