use std::cell::Cell;

use icrate::Foundation::{MainThreadMarker, NSObject};
use objc2::rc::Id;
use objc2::{declare_class, msg_send_id, mutability, ClassType, DeclaredClass};

use super::app_state::{self};
use super::uikit::{
    UIDevice, UIInterfaceOrientationMask, UIResponder, UIStatusBarStyle, UIView, UIViewController,
};
use crate::{
    platform::ios::ValidOrientations,
    platform_impl::platform::ffi::{UIRectEdge, UIUserInterfaceIdiom},
    window::WindowAttributes,
};

pub struct ViewControllerState {
    prefers_status_bar_hidden: Cell<bool>,
    preferred_status_bar_style: Cell<UIStatusBarStyle>,
    prefers_home_indicator_auto_hidden: Cell<bool>,
    supported_orientations: Cell<UIInterfaceOrientationMask>,
    preferred_screen_edges_deferring_system_gestures: Cell<UIRectEdge>,
}

declare_class!(
    pub(crate) struct WinitViewController;

    unsafe impl ClassType for WinitViewController {
        #[inherits(UIResponder, NSObject)]
        type Super = UIViewController;
        type Mutability = mutability::InteriorMutable;
        const NAME: &'static str = "WinitUIViewController";
    }

    impl DeclaredClass for WinitViewController {
        type Ivars = ViewControllerState;
    }

    unsafe impl WinitViewController {
        #[method(shouldAutorotate)]
        fn should_autorotate(&self) -> bool {
            true
        }

        #[method(prefersStatusBarHidden)]
        fn prefers_status_bar_hidden(&self) -> bool {
            self.ivars().prefers_status_bar_hidden.get()
        }

        #[method(preferredStatusBarStyle)]
        fn preferred_status_bar_style(&self) -> UIStatusBarStyle {
            self.ivars().preferred_status_bar_style.get()
        }

        #[method(prefersHomeIndicatorAutoHidden)]
        fn prefers_home_indicator_auto_hidden(&self) -> bool {
            self.ivars().prefers_home_indicator_auto_hidden.get()
        }

        #[method(supportedInterfaceOrientations)]
        fn supported_orientations(&self) -> UIInterfaceOrientationMask {
            self.ivars().supported_orientations.get()
        }

        #[method(preferredScreenEdgesDeferringSystemGestures)]
        fn preferred_screen_edges_deferring_system_gestures(&self) -> UIRectEdge {
            self.ivars()
                .preferred_screen_edges_deferring_system_gestures
                .get()
        }
    }
);

impl WinitViewController {
    pub(crate) fn set_prefers_status_bar_hidden(&self, val: bool) {
        self.ivars().prefers_status_bar_hidden.set(val);
        self.setNeedsStatusBarAppearanceUpdate();
    }

    pub(crate) fn set_preferred_status_bar_style(&self, val: UIStatusBarStyle) {
        self.ivars().preferred_status_bar_style.set(val);
        self.setNeedsStatusBarAppearanceUpdate();
    }

    pub(crate) fn set_prefers_home_indicator_auto_hidden(&self, val: bool) {
        self.ivars().prefers_home_indicator_auto_hidden.set(val);
        let os_capabilities = app_state::os_capabilities();
        if os_capabilities.home_indicator_hidden {
            self.setNeedsUpdateOfHomeIndicatorAutoHidden();
        } else {
            os_capabilities.home_indicator_hidden_err_msg("ignoring")
        }
    }

    pub(crate) fn set_preferred_screen_edges_deferring_system_gestures(&self, val: UIRectEdge) {
        self.ivars()
            .preferred_screen_edges_deferring_system_gestures
            .set(val);
        let os_capabilities = app_state::os_capabilities();
        if os_capabilities.defer_system_gestures {
            self.setNeedsUpdateOfScreenEdgesDeferringSystemGestures();
        } else {
            os_capabilities.defer_system_gestures_err_msg("ignoring")
        }
    }

    pub(crate) fn set_supported_interface_orientations(
        &self,
        mtm: MainThreadMarker,
        valid_orientations: ValidOrientations,
    ) {
        let mask = match (
            valid_orientations,
            UIDevice::current(mtm).userInterfaceIdiom(),
        ) {
            (ValidOrientations::LandscapeAndPortrait, UIUserInterfaceIdiom::Phone) => {
                UIInterfaceOrientationMask::AllButUpsideDown
            }
            (ValidOrientations::LandscapeAndPortrait, _) => UIInterfaceOrientationMask::All,
            (ValidOrientations::Landscape, _) => UIInterfaceOrientationMask::Landscape,
            (ValidOrientations::Portrait, UIUserInterfaceIdiom::Phone) => {
                UIInterfaceOrientationMask::Portrait
            }
            (ValidOrientations::Portrait, _) => {
                UIInterfaceOrientationMask::Portrait
                    | UIInterfaceOrientationMask::PortraitUpsideDown
            }
        };
        self.ivars().supported_orientations.set(mask);
        UIViewController::attemptRotationToDeviceOrientation();
    }

    pub(crate) fn new(
        mtm: MainThreadMarker,
        window_attributes: &WindowAttributes,
        view: &UIView,
    ) -> Id<Self> {
        // These are set properly below, we just to set them to something in the meantime.
        let this = Self::alloc().set_ivars(ViewControllerState {
            prefers_status_bar_hidden: Cell::new(false),
            preferred_status_bar_style: Cell::new(UIStatusBarStyle::Default),
            prefers_home_indicator_auto_hidden: Cell::new(false),
            supported_orientations: Cell::new(UIInterfaceOrientationMask::All),
            preferred_screen_edges_deferring_system_gestures: Cell::new(UIRectEdge::NONE),
        });
        let this: Id<Self> = unsafe { msg_send_id![super(this), init] };

        this.set_prefers_status_bar_hidden(
            window_attributes
                .platform_specific
                .prefers_status_bar_hidden,
        );

        this.set_preferred_status_bar_style(
            window_attributes
                .platform_specific
                .preferred_status_bar_style
                .into(),
        );

        this.set_supported_interface_orientations(
            mtm,
            window_attributes.platform_specific.valid_orientations,
        );

        this.set_prefers_home_indicator_auto_hidden(
            window_attributes
                .platform_specific
                .prefers_home_indicator_hidden,
        );

        this.set_preferred_screen_edges_deferring_system_gestures(
            window_attributes
                .platform_specific
                .preferred_screen_edges_deferring_system_gestures
                .into(),
        );

        this.setView(Some(view));

        this
    }
}