#include "Exception.h"

#include <cstring>
#include <cxxabi.h>
#include <cstdlib>
#include <Poco/String.h>
#include <Common/logger_useful.h>
#include <IO/WriteHelpers.h>
#include <IO/ReadHelpers.h>
#include <IO/Operators.h>
#include <IO/ReadBufferFromString.h>
#include <IO/ReadBufferFromFile.h>
#include <base/demangle.h>
#include <base/errnoToString.h>
#include <Common/formatReadable.h>
#include <Common/filesystemHelpers.h>
#include <Common/ErrorCodes.h>
#include <Common/LockMemoryExceptionInThread.h>
#include <filesystem>

#include <Common/config_version.h>

namespace fs = std::filesystem;

namespace DB
{

namespace ErrorCodes
{
    extern const int POCO_EXCEPTION;
    extern const int STD_EXCEPTION;
    extern const int UNKNOWN_EXCEPTION;
    extern const int LOGICAL_ERROR;
    extern const int CANNOT_ALLOCATE_MEMORY;
    extern const int CANNOT_MREMAP;
}

void abortOnFailedAssertion(const String & description)
{
    LOG_FATAL(&Poco::Logger::root(), "Logical error: '{}'.", description);

    /// This is to suppress -Wmissing-noreturn
    volatile bool always_false = false;
    if (always_false)
        return;

    abort();
}

/// - Aborts the process if error code is LOGICAL_ERROR.
/// - Increments error codes statistics.
void handle_error_code([[maybe_unused]] const std::string & msg, int code, bool remote, const Exception::FramePointers & trace)
{
    // In debug builds and builds with sanitizers, treat LOGICAL_ERROR as an assertion failure.
    // Log the message before we fail.
#ifdef ABORT_ON_LOGICAL_ERROR
    if (code == ErrorCodes::LOGICAL_ERROR)
    {
        abortOnFailedAssertion(msg);
    }
#endif

    ErrorCodes::increment(code, remote, msg, trace);
}

Exception::Exception(const std::string & msg, int code, bool remote_)
    : Poco::Exception(msg, code)
    , remote(remote_)
{
    handle_error_code(msg, code, remote, getStackFramePointers());
}

Exception::Exception(CreateFromPocoTag, const Poco::Exception & exc)
    : Poco::Exception(exc.displayText(), ErrorCodes::POCO_EXCEPTION)
{
#ifdef STD_EXCEPTION_HAS_STACK_TRACE
    set_stack_trace(exc.get_stack_trace_frames(), exc.get_stack_trace_size());
#endif
}

Exception::Exception(CreateFromSTDTag, const std::exception & exc)
    : Poco::Exception(demangle(typeid(exc).name()) + ": " + String(exc.what()), ErrorCodes::STD_EXCEPTION)
{
#ifdef STD_EXCEPTION_HAS_STACK_TRACE
    set_stack_trace(exc.get_stack_trace_frames(), exc.get_stack_trace_size());
#endif
}


std::string getExceptionStackTraceString(const std::exception & e)
{
#ifdef STD_EXCEPTION_HAS_STACK_TRACE
    return StackTrace::toString(e.get_stack_trace_frames(), 0, e.get_stack_trace_size());
#else
    if (const auto * db_exception = dynamic_cast<const Exception *>(&e))
        return db_exception->getStackTraceString();
    return {};
#endif
}

std::string getExceptionStackTraceString(std::exception_ptr e)
{
    try
    {
        std::rethrow_exception(e);
    }
    catch (const std::exception & exception)
    {
        return getExceptionStackTraceString(exception);
    }
    catch (...)
    {
        return {};
    }
}


std::string Exception::getStackTraceString() const
{
#ifdef STD_EXCEPTION_HAS_STACK_TRACE
    return StackTrace::toString(get_stack_trace_frames(), 0, get_stack_trace_size());
#else
    return trace.toString();
#endif
}

Exception::FramePointers Exception::getStackFramePointers() const
{
    FramePointers frame_pointers;
#ifdef STD_EXCEPTION_HAS_STACK_TRACE
    {
        frame_pointers.resize(get_stack_trace_size());
        for (size_t i = 0; i < frame_pointers.size(); ++i)
        {
            frame_pointers[i] = get_stack_trace_frames()[i];
        }
    }
#else
    {
        size_t stack_trace_size = trace.getSize();
        size_t stack_trace_offset = trace.getOffset();
        frame_pointers.reserve(stack_trace_size - stack_trace_offset);
        for (size_t i = stack_trace_offset; i < stack_trace_size; ++i)
        {
            frame_pointers.push_back(trace.getFramePointers()[i]);
        }
    }
#endif
    return frame_pointers;
}


void throwFromErrno(const std::string & s, int code, int the_errno)
{
    throw ErrnoException(s + ", " + errnoToString(the_errno), code, the_errno);
}

void throwFromErrnoWithPath(const std::string & s, const std::string & path, int code, int the_errno)
{
    throw ErrnoException(s + ", " + errnoToString(the_errno), code, the_errno, path);
}

static void tryLogCurrentExceptionImpl(Poco::Logger * logger, const std::string & start_of_message)
{
    try
    {
        if (start_of_message.empty())
            LOG_ERROR(logger, "{}", getCurrentExceptionMessage(true));
        else
            LOG_ERROR(logger, "{}: {}", start_of_message, getCurrentExceptionMessage(true));
    }
    catch (...)
    {
    }
}

void tryLogCurrentException(const char * log_name, const std::string & start_of_message)
{
    /// Under high memory pressure, any new allocation will definitelly lead
    /// to MEMORY_LIMIT_EXCEEDED exception.
    ///
    /// And in this case the exception will not be logged, so let's block the
    /// MemoryTracker until the exception will be logged.
    LockMemoryExceptionInThread lock_memory_tracker(VariableContext::Global);

    /// Poco::Logger::get can allocate memory too
    tryLogCurrentExceptionImpl(&Poco::Logger::get(log_name), start_of_message);
}

void tryLogCurrentException(Poco::Logger * logger, const std::string & start_of_message)
{
    /// Under high memory pressure, any new allocation will definitelly lead
    /// to MEMORY_LIMIT_EXCEEDED exception.
    ///
    /// And in this case the exception will not be logged, so let's block the
    /// MemoryTracker until the exception will be logged.
    LockMemoryExceptionInThread lock_memory_tracker(VariableContext::Global);

    tryLogCurrentExceptionImpl(logger, start_of_message);
}

static void getNoSpaceLeftInfoMessage(std::filesystem::path path, String & msg)
{
    path = std::filesystem::absolute(path);
    /// It's possible to get ENOSPC for non existent file (e.g. if there are no free inodes and creat() fails)
    /// So try to get info for existent parent directory.
    while (!std::filesystem::exists(path) && path.has_relative_path())
        path = path.parent_path();

    auto fs = getStatVFS(path);
    auto mount_point = getMountPoint(path).string();

    fmt::format_to(std::back_inserter(msg),
        "\nTotal space: {}\nAvailable space: {}\nTotal inodes: {}\nAvailable inodes: {}\nMount point: {}",
        ReadableSize(fs.f_blocks * fs.f_frsize),
        ReadableSize(fs.f_bavail * fs.f_frsize),
        formatReadableQuantity(fs.f_files),
        formatReadableQuantity(fs.f_favail),
        mount_point);

#if defined(OS_LINUX)
    msg += "\nFilesystem: " + getFilesystemName(mount_point);
#endif
}


/** It is possible that the system has enough memory,
  *  but we have shortage of the number of available memory mappings.
  * Provide good diagnostic to user in that case.
  */
static void getNotEnoughMemoryMessage(std::string & msg)
{
#if defined(OS_LINUX)
    try
    {
        static constexpr size_t buf_size = 1024;
        char buf[buf_size];

        UInt64 max_map_count = 0;
        {
            ReadBufferFromFile file("/proc/sys/vm/max_map_count", buf_size, -1, buf);
            readText(max_map_count, file);
        }

        UInt64 num_maps = 0;
        {
            ReadBufferFromFile file("/proc/self/maps", buf_size, -1, buf);
            while (!file.eof())
            {
                char * next_pos = find_first_symbols<'\n'>(file.position(), file.buffer().end());
                file.position() = next_pos;

                if (!file.hasPendingData())
                    continue;

                if (*file.position() == '\n')
                {
                    ++num_maps;
                    ++file.position();
                }
            }
        }

        if (num_maps > max_map_count * 0.90)
        {
            msg += fmt::format(
                "\nIt looks like that the process is near the limit on number of virtual memory mappings."
                "\nCurrent number of mappings (/proc/self/maps): {}."
                "\nLimit on number of mappings (/proc/sys/vm/max_map_count): {}."
                "\nYou should increase the limit for vm.max_map_count in /etc/sysctl.conf"
                "\n",
                num_maps, max_map_count);
        }
    }
    catch (...)
    {
        msg += "\nCannot obtain additional info about memory usage.";
    }
#else
    (void)msg;
#endif
}

std::string getExtraExceptionInfo(const std::exception & e)
{
    String msg;
    try
    {
        if (const auto * file_exception = dynamic_cast<const fs::filesystem_error *>(&e))
        {
            if (file_exception->code() == std::errc::no_space_on_device)
                getNoSpaceLeftInfoMessage(file_exception->path1(), msg);
            else
                msg += "\nCannot print extra info for Poco::Exception";
        }
        else if (const auto * errno_exception = dynamic_cast<const DB::ErrnoException *>(&e))
        {
            if (errno_exception->getErrno() == ENOSPC && errno_exception->getPath())
                getNoSpaceLeftInfoMessage(errno_exception->getPath().value(), msg);
            else if (errno_exception->code() == ErrorCodes::CANNOT_ALLOCATE_MEMORY
                || errno_exception->code() == ErrorCodes::CANNOT_MREMAP)
                getNotEnoughMemoryMessage(msg);
        }
        else if (dynamic_cast<const std::bad_alloc *>(&e))
        {
            getNotEnoughMemoryMessage(msg);
        }
    }
    catch (...)
    {
        msg += "\nCannot print extra info: " + getCurrentExceptionMessage(false, false, false);
    }

    return msg;
}

std::string getCurrentExceptionMessage(bool with_stacktrace, bool check_embedded_stacktrace /*= false*/, bool with_extra_info /*= true*/)
{
    WriteBufferFromOwnString stream;

    try
    {
        throw;
    }
    catch (const Exception & e)
    {
        stream << getExceptionMessage(e, with_stacktrace, check_embedded_stacktrace)
               << (with_extra_info ? getExtraExceptionInfo(e) : "")
               << " (version " << VERSION_STRING << VERSION_OFFICIAL << ")";
    }
    catch (const Poco::Exception & e)
    {
        try
        {
            stream << "Poco::Exception. Code: " << ErrorCodes::POCO_EXCEPTION << ", e.code() = " << e.code()
                << ", " << e.displayText()
                << (with_stacktrace ? ", Stack trace (when copying this message, always include the lines below):\n\n" + getExceptionStackTraceString(e) : "")
                << (with_extra_info ? getExtraExceptionInfo(e) : "")
                << " (version " << VERSION_STRING << VERSION_OFFICIAL << ")";
        }
        catch (...) {}
    }
    catch (const std::exception & e)
    {
        try
        {
            int status = 0;
            auto name = demangle(typeid(e).name(), status);

            if (status)
                name += " (demangling status: " + toString(status) + ")";

            stream << "std::exception. Code: " << ErrorCodes::STD_EXCEPTION << ", type: " << name << ", e.what() = " << e.what()
                << (with_stacktrace ? ", Stack trace (when copying this message, always include the lines below):\n\n" + getExceptionStackTraceString(e) : "")
                << (with_extra_info ? getExtraExceptionInfo(e) : "")
                << " (version " << VERSION_STRING << VERSION_OFFICIAL << ")";
        }
        catch (...) {}
    }
    catch (...)
    {
        try
        {
            int status = 0;
            auto name = demangle(abi::__cxa_current_exception_type()->name(), status);

            if (status)
                name += " (demangling status: " + toString(status) + ")";

            stream << "Unknown exception. Code: " << ErrorCodes::UNKNOWN_EXCEPTION << ", type: " << name << " (version " << VERSION_STRING << VERSION_OFFICIAL << ")";
        }
        catch (...) {}
    }

    return stream.str();
}


int getCurrentExceptionCode()
{
    try
    {
        throw;
    }
    catch (const Exception & e)
    {
        return e.code();
    }
    catch (const Poco::Exception &)
    {
        return ErrorCodes::POCO_EXCEPTION;
    }
    catch (const std::exception &)
    {
        return ErrorCodes::STD_EXCEPTION;
    }
    catch (...)
    {
        return ErrorCodes::UNKNOWN_EXCEPTION;
    }
}

int getExceptionErrorCode(std::exception_ptr e)
{
    try
    {
        std::rethrow_exception(e);
    }
    catch (const Exception & exception)
    {
        return exception.code();
    }
    catch (const Poco::Exception &)
    {
        return ErrorCodes::POCO_EXCEPTION;
    }
    catch (const std::exception &)
    {
        return ErrorCodes::STD_EXCEPTION;
    }
    catch (...)
    {
        return ErrorCodes::UNKNOWN_EXCEPTION;
    }
}


void rethrowFirstException(const Exceptions & exceptions)
{
    for (const auto & exception : exceptions)
        if (exception)
            std::rethrow_exception(exception);
}


void tryLogException(std::exception_ptr e, const char * log_name, const std::string & start_of_message)
{
    try
    {
        std::rethrow_exception(std::move(e)); // NOLINT
    }
    catch (...)
    {
        tryLogCurrentException(log_name, start_of_message);
    }
}

void tryLogException(std::exception_ptr e, Poco::Logger * logger, const std::string & start_of_message)
{
    try
    {
        std::rethrow_exception(std::move(e)); // NOLINT
    }
    catch (...)
    {
        tryLogCurrentException(logger, start_of_message);
    }
}

std::string getExceptionMessage(const Exception & e, bool with_stacktrace, bool check_embedded_stacktrace)
{
    WriteBufferFromOwnString stream;

    try
    {
        std::string text = e.displayText();

        bool has_embedded_stack_trace = false;
        if (check_embedded_stacktrace)
        {
            auto embedded_stack_trace_pos = text.find("Stack trace");
            has_embedded_stack_trace = embedded_stack_trace_pos != std::string::npos;
            if (!with_stacktrace && has_embedded_stack_trace)
            {
                text.resize(embedded_stack_trace_pos);
                Poco::trimRightInPlace(text);
            }
        }

        stream << "Code: " << e.code() << ". " << text;

        if (!text.empty() && text.back() != '.')
            stream << '.';

        stream << " (" << ErrorCodes::getName(e.code()) << ")";

        if (with_stacktrace && !has_embedded_stack_trace)
            stream << ", Stack trace (when copying this message, always include the lines below):\n\n" << e.getStackTraceString();
    }
    catch (...) {}

    return stream.str();
}

std::string getExceptionMessage(std::exception_ptr e, bool with_stacktrace)
{
    try
    {
        std::rethrow_exception(std::move(e)); // NOLINT
    }
    catch (...)
    {
        return getCurrentExceptionMessage(with_stacktrace);
    }
}


std::string ExecutionStatus::serializeText() const
{
    WriteBufferFromOwnString wb;
    wb << code << "\n" << escape << message;
    return wb.str();
}

void ExecutionStatus::deserializeText(const std::string & data)
{
    ReadBufferFromString rb(data);
    rb >> code >> "\n" >> escape >> message;
}

bool ExecutionStatus::tryDeserializeText(const std::string & data)
{
    try
    {
        deserializeText(data);
    }
    catch (...)
    {
        return false;
    }

    return true;
}

ExecutionStatus ExecutionStatus::fromCurrentException(const std::string & start_of_message)
{
    String msg = (start_of_message.empty() ? "" : (start_of_message + ": ")) + getCurrentExceptionMessage(false, true);
    return ExecutionStatus(getCurrentExceptionCode(), msg);
}

ExecutionStatus ExecutionStatus::fromText(const std::string & data)
{
    ExecutionStatus status;
    status.deserializeText(data);
    return status;
}

ParsingException::ParsingException() = default;
ParsingException::ParsingException(const std::string & msg, int code)
    : Exception(msg, code)
{
}
ParsingException::ParsingException(int code, const std::string & message)
    : Exception(message, code)
{
}

/// We use additional field formatted_message_ to make this method const.
std::string ParsingException::displayText() const
{
    try
    {
        formatted_message = message();
        bool need_newline = false;
        if (!file_name.empty())
        {
            formatted_message += fmt::format(": (in file/uri {})", file_name);
            need_newline = true;
        }

        if (line_number != -1)
        {
            formatted_message += fmt::format(": (at row {})", line_number);
            need_newline = true;
        }

        if (need_newline)
            formatted_message += "\n";
    }
    catch (...) {}

    if (!formatted_message.empty())
    {
        std::string result = name();
        result.append(": ");
        result.append(formatted_message);
        return result;
    }
    else
    {
        return Exception::displayText();
    }
}


}