#include "deimos/core/log.h"
#include "deimos/core/api_registry.h"
#include "deimos/core/allocator.h"
#include "deimos/core/os.h"

namespace deimos
{

class DefaultLogger : public ILogger
{
    OsConsoleWriter m_writer;

    static const char* SeverityToStr(LogSeverity s)
    {
        switch (s)
        {
            case LogSeverity::kInfo: return "INFO ";
            case LogSeverity::kDebug: return "DEBUG";
            case LogSeverity::kError: return "ERROR";
        }
    }

    static const char* SeverityToColor(LogSeverity s)
    {
        switch (s)
        {
            case LogSeverity::kInfo: return "";
            case LogSeverity::kDebug: return "\033[2m";
            case LogSeverity::kError: return "\033[91m";
        }
    }

public:
    explicit DefaultLogger(OsConsoleApi* os_console_api) :
        m_writer(os_console_api, OsConsoleType::kStdOut)
    {}

    void Log(LogSeverity severity, const SourceLocation& /* location */, StringView msg) override
    {
        // Format(&m_writer, "$[ $ ] $:$: $\033[0m\n", SeverityToColor(severity),
        //     SeverityToStr(severity), location.file, location.line, msg);
        Format(&m_writer, "$[ $ ] $\033[0m\n", SeverityToColor(severity),
            SeverityToStr(severity), msg);
    }
};

class LogApiImpl : public LogApi
{
    gsl::owner<ILogger*> m_default_logger;

public:
    explicit LogApiImpl(gsl::owner<ILogger*> default_logger) :
        m_default_logger{default_logger}
    {}

    void LogVa(
        LogSeverity severity,
        const SourceLocation& location,
        gsl::czstring msg,
        Span<const FormatArg> args) override
    {
        std::byte buffer[1024];
        BufferWriter message_writer({&buffer[0], 1024});
        FormatVa(&message_writer, msg, args);

        auto written = message_writer.GetWritten();
        m_default_logger->Log(severity, location, {reinterpret_cast<const char*>(written.data()), written.size()});
    }
};

void RegisterLogApi(ApiRegistry* api_registry)
{
    auto* allocator = api_registry->Get<AllocatorApi>()->system;
    auto* os_console_api = api_registry->Get<OsApi>()->console;

    gsl::owner<ILogger*> default_logger = allocator->New<DefaultLogger>(os_console_api);
    gsl::owner<LogApi*> log_api = allocator->New<LogApiImpl>(default_logger);

    api_registry->Set(log_api);
}

} // namespace deimos