#include <security/pam_appl.h>
#include <security/pam_client.h>
#include <security/pam_ext.h>
#include <security/pam_misc.h>
#include <security/pam_modules.h>

#include <rublon/init.hpp>
#include <rublon/json.hpp>
#include <rublon/pam.hpp>
#include <rublon/rublon.hpp>
#include <rublon/utils.hpp>

#define DLL_PUBLIC __attribute__((visibility("default")))

using namespace std;

DLL_PUBLIC int pam_sm_setcred([[maybe_unused]] pam_handle_t * pamh,
  [[maybe_unused]] int flags,
  [[maybe_unused]] int argc,
  [[maybe_unused]] const char ** argv) {
    return PAM_SUCCESS;
}

DLL_PUBLIC int pam_sm_acct_mgmt([[maybe_unused]] pam_handle_t * pamh,
  [[maybe_unused]] int flags,
  [[maybe_unused]] int argc,
  [[maybe_unused]] const char ** argv) {
    return PAM_SUCCESS;
}

DLL_PUBLIC int
pam_sm_authenticate(pam_handle_t * pamh, [[maybe_unused]] int flags, [[maybe_unused]] int argc, [[maybe_unused]] const char ** argv) {
    using namespace rublon;

    auto rublonConfig = ConfigurationFactory{}.systemConfig();

    std::byte sharedMemory[32 * 1024] = {};
    std::pmr::monotonic_buffer_resource mr{sharedMemory, std::size(sharedMemory)};
    std::pmr::unsynchronized_pool_resource rublonPoolResource{&mr};
    std::pmr::set_default_resource(&rublonPoolResource);

    CoreHandler CH{rublonConfig.value()};
    LinuxPam pam{pamh};

    auto selectMethod  = [&](const MethodSelect & selector) { return selector.create(pam); };
    auto confirmMethod = [&](const PostMethod & confirm) { return confirm.fire(CH); };
    auto verifi        = [&](const MethodProxy & method) { return method.fire(CH, pam); };

    auto authStatus = Init{rublonConfig.value()}
                        .fire(CH, pam) //
                        .and_then(selectMethod)
                        .and_then(confirmMethod)
                        .and_then(verifi);

    if(authStatus.has_value()) {
        rublon::log(rublon::LogLevel::Info, "Auth OK");
        return PAM_SUCCESS;
    } else {
        const auto & error = authStatus.error();

        rublon::log(
          LogLevel::Error, "auth failed due to %d class and %d category", error.errorClass(), static_cast< int >(error.category()));
    }

    rublon::log(LogLevel::Warning, "User login failed");
    return PAM_PERM_DENIED;
}