Exception.h

/*
 * MIT License
 *
 * Copyright (c) 2025 Adriano dos Santos Fernandes
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
 
#ifndef FBCPP_EXCEPTION_H
#define FBCPP_EXCEPTION_H
 
#include "fb-api.h"
#include <stdexcept>
#include <string>
#include <vector>
#include <cstdint>
 
 
namespace fbcpp
{
    class Client;
}
 
namespace fbcpp::impl
{
    class StatusWrapper : public fb::IStatusImpl<StatusWrapper, StatusWrapper>
    {
    public:
        explicit StatusWrapper(Client& client, IStatus* status = nullptr)
            : client{&client},
              status{status}
        {
        }
 
        StatusWrapper(StatusWrapper&& o) noexcept
            : client{o.client},
              status{o.status},
              statusOwner{o.statusOwner},
              dirty{o.dirty}
        {
            o.status = nullptr;
            o.statusOwner = false;
            o.dirty = false;
        }
 
        StatusWrapper& operator=(StatusWrapper&& o) noexcept
        {
            if (this != &o)
            {
                if (statusOwner && status)
                    status->dispose();
 
                client = o.client;
                status = o.status;
                statusOwner = o.statusOwner;
                dirty = o.dirty;
 
                o.status = nullptr;
                o.statusOwner = false;
                o.dirty = false;
            }
 
            return *this;
        }
 
        StatusWrapper(const StatusWrapper&) = delete;
        StatusWrapper& operator=(const StatusWrapper&) = delete;
 
        ~StatusWrapper()
        {
            if (statusOwner && status)
                status->dispose();
        }
 
    public:
        static void checkException(StatusWrapper* status);
 
        static void catchException(IStatus* status) noexcept;
 
        static void clearException(StatusWrapper* status) noexcept
        {
            status->clearException();
        }
 
        void clearException()
        {
            if (dirty)
            {
                dirty = false;
                getStatus()->init();
            }
        }
 
        bool isDirty() const noexcept
        {
            return dirty;
        }
 
        bool hasData() const noexcept
        {
            return getState() & IStatus::STATE_ERRORS;
        }
 
        bool isEmpty() const noexcept
        {
            return !hasData();
        }
 
        static void setVersionError(
            IStatus* status, const char* interfaceName, uintptr_t currentVersion, uintptr_t expectedVersion) noexcept
        {
            // clang-format off
            const intptr_t codes[] = {
                isc_arg_gds, isc_interface_version_too_old,
                isc_arg_number, (intptr_t) expectedVersion,
                isc_arg_number, (intptr_t) currentVersion,
                isc_arg_string, (intptr_t) interfaceName,
                isc_arg_end,
            };
            // clang-format on
 
            status->setErrors(codes);
        }
 
    public:
        void dispose() noexcept override
        {
            // Disposes only the delegated status. Let the user destroy this instance.
            if (status)
                status->dispose();
 
            status = nullptr;
            statusOwner = false;
        }
 
        void init() noexcept override
        {
            clearException();
        }
 
        unsigned getState() const noexcept override
        {
            return dirty ? getStatus()->getState() : 0;
        }
 
        void setErrors2(unsigned length, const intptr_t* value) noexcept override
        {
            dirty = true;
            getStatus()->setErrors2(length, value);
        }
 
        void setWarnings2(unsigned length, const intptr_t* value) noexcept override
        {
            dirty = true;
            getStatus()->setWarnings2(length, value);
        }
 
        void setErrors(const intptr_t* value) noexcept override
        {
            dirty = true;
            getStatus()->setErrors(value);
        }
 
        void setWarnings(const intptr_t* value) noexcept override
        {
            dirty = true;
            getStatus()->setWarnings(value);
        }
 
        const intptr_t* getErrors() const noexcept override
        {
            return dirty ? getStatus()->getErrors() : cleanStatus();
        }
 
        const intptr_t* getWarnings() const noexcept override
        {
            return dirty ? getStatus()->getWarnings() : cleanStatus();
        }
 
        IStatus* clone() const noexcept override
        {
            return getStatus()->clone();
        }
 
    protected:
        Client* client;
        mutable IStatus* status;
        mutable bool statusOwner = false;
        bool dirty = false;
 
        IStatus* getStatus() const;
 
        static const intptr_t* cleanStatus() noexcept
        {
            static intptr_t clean[3] = {1, 0, 0};
            return clean;
        }
    };
}  // namespace fbcpp::impl
 
 
namespace fbcpp
{
    class FbCppException : public std::runtime_error
    {
    public:
        using std::runtime_error::runtime_error;
 
        explicit FbCppException(const std::string& message)
            : std::runtime_error{message}
        {
        }
    };
 
    class DatabaseException final : public FbCppException
    {
    public:
        explicit DatabaseException(Client& client, const std::intptr_t* statusVector)
            : FbCppException{buildMessage(client, statusVector)},
              sqlState{extractSqlState(statusVector)}
        {
            copyErrorVector(statusVector);
        }
 
        DatabaseException(const DatabaseException& other)
            : FbCppException{static_cast<const FbCppException&>(other)},
              errorVector{other.errorVector},
              errorStrings{other.errorStrings},
              sqlState{other.sqlState}
        {
            fixupStringPointers();
        }
 
        DatabaseException(DatabaseException&&) = default;
 
        DatabaseException& operator=(const DatabaseException&) = delete;
        DatabaseException& operator=(DatabaseException&&) = delete;
 
        const std::vector<std::intptr_t>& getErrors() const noexcept
        {
            return errorVector;
        }
 
        std::intptr_t getErrorCode() const noexcept
        {
            if (errorVector.size() >= 2 && errorVector[0] == isc_arg_gds)
                return errorVector[1];
            return 0;
        }
 
        const std::string& getSqlState() const noexcept
        {
            return sqlState;
        }
 
    private:
        static std::string buildMessage(Client& client, const std::intptr_t* statusVector);
        static std::string extractSqlState(const std::intptr_t* statusVector);
 
        void copyErrorVector(const std::intptr_t* statusVector);
        void fixupStringPointers();
 
    private:
        std::vector<std::intptr_t> errorVector;
        std::vector<std::string> errorStrings;
        std::string sqlState;
    };
}  // namespace fbcpp
 
 
#endif  // FBCPP_EXCEPTION_H