use std::future::Future;

use giterated_models::{
    error::OperationError,
    object::GiteratedObject,
    settings::{AnySetting, Setting},
};

use crate::{
    future::{RuntimeFuture, RuntimeFuturesExt},
    new_stack::PluginState,
    AnyObject, NewAnySetting,
};

use super::{CallbackPtr, RuntimeState};

#[derive(Clone, Copy)]
pub struct SettingGetterCallback {
    pub callback_ptr: CallbackPtr,
    pub func: unsafe extern "C" fn(
        CallbackPtr,
        runtime_state: &RuntimeState,
        &PluginState,
        object: AnyObject,
    ) -> RuntimeFuture<Result<NewAnySetting, ()>>,
}

impl SettingGetterCallback {
    pub fn new<S, O, OS, T: IntoPluginSettingGetter<S, O, OS>>(callback: T) -> Self {
        Self {
            func: T::get_setting,
            callback_ptr: callback.callback_ptr(),
        }
    }
}

pub trait IntoPluginSettingGetter<S, O, OS> {
    unsafe extern "C" fn get_setting(
        callback_ptr: CallbackPtr,
        runtime_state: &RuntimeState,
        state: &PluginState,
        object: AnyObject,
    ) -> RuntimeFuture<Result<NewAnySetting, ()>>;

    fn callback_ptr(&self) -> CallbackPtr {
        unsafe { CallbackPtr::from_raw(self as *const _ as *const ()) }
    }
}

impl<F, S, O, OS, Fut> IntoPluginSettingGetter<S, O, OS> for F
where
    Fut: Future<Output = Result<OS, OperationError<anyhow::Error>>> + Send + Sync + 'static,
    S: Clone + Send + Sync + 'static,
    O: GiteratedObject + Send + Sync + 'static,
    OS: Setting + Send + Sync + 'static,
    F: Fn(S, O) -> Fut + Send + Sync + 'static,
{
    unsafe extern "C" fn get_setting(
        callback: CallbackPtr,
        runtime_state: &RuntimeState,
        state: &PluginState,
        mut object: AnyObject,
    ) -> RuntimeFuture<Result<NewAnySetting, ()>> {
        let _guard = trace_span!(
            "get_setting handler",
            object = O::object_name(),
            setting = OS::name()
        )
        .entered();
        let state = unsafe { state.transmute_ref::<S>() };

        let object = unsafe { object.transmute_owned::<O>() };

        // Cast the callback ptr to ourselves
        let callback: *const F = std::mem::transmute(callback.0);
        let callback = callback.as_ref().unwrap();

        let state = state.clone();
        runtime_state.spawn_future(async move {
            let result = callback(state, *object).await;

            match result {
                Ok(success) => unsafe { Ok(NewAnySetting::new(success)) },
                Err(err) => match err {
                    OperationError::Operation(_) => todo!(),
                    OperationError::Internal(_) => todo!(),
                    OperationError::Unhandled => todo!(),
                },
            }
        })
    }
}

pub trait IntoPluginSettingSetter<S, O, OS> {
    unsafe extern "C" fn set_setting(
        callback_ptr: CallbackPtr,
        state: &PluginState,
        object: AnyObject,
        setting: AnySetting,
    ) -> RuntimeFuture<Result<(), ()>>;

    fn callback_ptr(&self) -> CallbackPtr {
        unsafe { CallbackPtr::from_raw(self as *const _ as *const ()) }
    }
}

impl<F, S, O, OS, Fut> IntoPluginSettingSetter<S, O, OS> for F
where
    Fut: Future<Output = Result<(), OperationError<anyhow::Error>>>,
    S: Clone,
    O: GiteratedObject,
    OS: Setting,
    F: Fn(S, O, OS) -> Fut,
{
    unsafe extern "C" fn set_setting(
        callback: CallbackPtr,
        state: &PluginState,
        mut object: AnyObject,
        _setting: AnySetting,
    ) -> RuntimeFuture<Result<(), ()>> {
        let _guard = trace_span!(
            "get_setting handler",
            object = O::object_name(),
            setting = OS::name()
        )
        .entered();
        let _state = unsafe { state.transmute_ref::<S>() };

        let _object = unsafe { object.transmute_owned::<O>() };

        // Cast the callback ptr to ourselves
        let callback: *const F = std::mem::transmute(callback.0);
        let _callback = callback.as_ref().unwrap();

        // let result = callback(state.clone(), *object);

        // match result {
        //     Ok(setting) => Ok(NewAnySetting::new(setting)),
        //     Err(_) => todo!(),
        // }
        todo!()
    }
}

pub struct SettingChangeCallback {
    func: unsafe extern "C" fn(
        &PluginState,
        object: AnyObject,
        setting_name: &str,
        new_setting: NewAnySetting,
    ),
}

pub trait IntoSettingChangeCallback<S, O> {
    unsafe extern "C" fn setting_changed(
        state: &PluginState,
        object: AnyObject,
        setting_name: &str,
        new_setting: NewAnySetting,
    );
}

impl<F, S, O> IntoSettingChangeCallback<S, O> for F {
    unsafe extern "C" fn setting_changed(
        _state: &PluginState,
        _object: AnyObject,
        _setting_name: &str,
        _new_setting: NewAnySetting,
    ) {
        todo!()
    }
}

impl SettingChangeCallback {
    pub fn new<S, O, T: IntoSettingChangeCallback<S, O>>() -> Self {
        Self {
            func: T::setting_changed,
        }
    }
}