nautilus-plugin 0.58.0

// -------------------------------------------------------------------------------------------------
//  Copyright (C) 2015-2026 Nautech Systems Pty Ltd. All rights reserved.
//  https://nautechsystems.io
//
//  Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
//  You may not use this file except in compliance with the License.
//  You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
// -------------------------------------------------------------------------------------------------

//! Boundary-owned handle for [`OptionChainSlice`].
//!
//! [`OptionChainSlice`] owns `BTreeMap<Price, OptionStrikeData>` call and
//! put maps and cannot be `#[repr(C)]`, so the host wraps it in a
//! `#[repr(C)]` handle that owns the boxed value and passes a borrowed
//! pointer to the plug-in. The plug-in's thunk dereferences the handle
//! once and hands an `&OptionChainSlice` to the trait method. Mirrors
//! the ownership contract that
//! [`OrderBookDeltasHandle`](crate::surfaces::book::OrderBookDeltasHandle)
//! uses for [`OrderBookDeltas`](nautilus_model::data::OrderBookDeltas).

#![allow(unsafe_code)]

use std::ops::Deref;

use nautilus_model::data::OptionChainSlice;

/// Boundary-owned wrapper that lets [`OptionChainSlice`] cross the
/// cdylib FFI boundary by reference.
///
/// The host constructs an instance, hands a
/// `*const OptionChainSliceHandle` to the plug-in for the duration of
/// the callback, and drops the handle when the call returns. The
/// plug-in only borrows the handle and never owns it.
#[repr(C)]
#[derive(Debug, Clone)]
pub struct OptionChainSliceHandle(Box<OptionChainSlice>);

impl OptionChainSliceHandle {
    /// Wraps `slice` in a boundary-owned handle.
    #[must_use]
    pub fn new(slice: OptionChainSlice) -> Self {
        Self(Box::new(slice))
    }

    /// Returns a reference to the wrapped option chain slice.
    #[must_use]
    pub fn chain(&self) -> &OptionChainSlice {
        &self.0
    }

    /// Consumes the wrapper and returns the inner option chain slice.
    #[must_use]
    pub fn into_inner(self) -> OptionChainSlice {
        *self.0
    }
}

impl Deref for OptionChainSliceHandle {
    type Target = OptionChainSlice;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}