// Copyright 2026 The BoringSSL Authors
//
// Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
//
// 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.

use alloc::ffi::CString;

use bssl_x509::store::X509Store;

use super::{Client, methods::HasTlsConnectionMethod};
use crate::{
    check_lib_error,
    config::ConfigurationError,
    connection::lifecycle::TlsConnectionInHandshake,
    credentials::{CertificateVerificationMode, TlsCredential},
    errors::Error,
};

/// # Custom certificate verification
impl<M> TlsConnectionInHandshake<'_, Client, M>
where
    M: HasTlsConnectionMethod,
{
    /// Configure the certificate verification mode.
    pub fn set_certificate_verification_mode(
        &mut self,
        mode: CertificateVerificationMode,
    ) -> &mut Self {
        let ctx = self.ptr();
        unsafe {
            // Safety: `ctx` is still valid here, `mode` has a correct value by construction and
            // `NULL` is a valid callback handle.
            bssl_sys::SSL_set_custom_verify(ctx, mode as _, None);
        }
        self
    }

    /// Get the certificate verification mode set by [`Self::set_certificate_verification_mode`].
    pub fn get_certificate_verification_mode(&self) -> Option<CertificateVerificationMode> {
        unsafe {
            // Safety: the validity of the handle `self.0` is witnessed by `self`.
            bssl_sys::SSL_get_verify_mode(self.ptr())
        }
        .try_into()
        .ok()
    }
}

/// # Authenticating with the peer
impl<M> TlsConnectionInHandshake<'_, Client, M>
where
    M: HasTlsConnectionMethod,
{
    /// Append `credential` to the list of credentials of this connection.
    ///
    /// Earlier calls to this method appends a credential that is preferred over those added
    /// in the later calls.
    pub fn add_credential(&mut self, credential: TlsCredential) -> Result<&mut Self, Error> {
        check_lib_error!(unsafe {
            // Safety: `credential` is still valid.
            bssl_sys::SSL_add1_credential(self.ptr(), credential.into_raw())
        });
        Ok(self)
    }

    /// Clear all credentials.
    pub fn clear_credentials(&mut self) -> &mut Self {
        unsafe {
            // Safety: `credential` is still valid.
            bssl_sys::SSL_certs_clear(self.ptr());
        }
        self
    }
}

/// # Certificate verification
impl<M> TlsConnectionInHandshake<'_, Client, M> {
    /// Set certificate verification store.
    pub fn set_certificate_store(&mut self, store: X509Store) -> &mut Self {
        unsafe {
            // Safety:
            // - the validity of the handle `self.0` is witnessed by `self`.
            // - when pending handshake, the assignment is always successful.
            // - `SSL_set1_verify_cert_store` bumps the ref-count on the store.
            bssl_sys::SSL_set1_verify_cert_store(self.ptr(), store.as_raw());
        }
        self
    }
}

/// # Certificate verification.
impl<M> TlsConnectionInHandshake<'_, Client, M> {
    /// Set host name.
    pub fn set_host(&mut self, host_name: &str) -> Result<&mut Self, Error> {
        let host_name = CString::new(host_name)
            .map_err(|_| Error::Configuration(ConfigurationError::InvalidString))?;
        check_lib_error!(unsafe {
            // Safety:
            // - the validity of the handle `self.0` is witnessed by `self`.
            // - the host name string has been sanitised for internal NUL-bytes and NUL-terminated.
            bssl_sys::SSL_set1_host(self.ptr(), host_name.as_ptr())
        });
        Ok(self)
    }
}