module;

#include <cstdio>
#include <source_location>

export module Core.Logger;

import Core.Terminal;
import Core.Meta;
import Core.ToString;

#define SOURCE const std::source_location& sl = std::source_location::current()

export namespace Core {
    enum class LogLevel { NONE, ERROR, WARNING, INFO, DEBUG };

    extern LogLevel logLevel;

    using ReportHandler = void (*)(
        LogLevel l, const std::source_location& sl, void* data,
        const char* message);
    void callReportHandler(LogLevel l, const char* report, SOURCE);
    void setReportHandler(ReportHandler h, void* data);

    struct FormatLocation final {
        const char* format;
        std::source_location location;

        FormatLocation(
            const char* f,
            const std::source_location& l = std::source_location::current()) :
            format(f), location(l) {
        }
    };

    template<typename... Args>
    void report(LogLevel l, const FormatLocation& format, Args&&... args) {
        char buffer[512];
        formatBuffer(
            buffer, sizeof(buffer), format.format,
            Core::forward<Args>(args)...);
        callReportHandler(l, buffer, format.location);
    }

    const char* getShortFileName(const char* s);

    template<typename... Args>
    void log(
        LogLevel l, const char* prefix, const FormatLocation& format,
        Args&&... args) {
        if(logLevel < l) {
            return;
        }
        const char* file = getShortFileName(format.location.file_name());
        fputs(prefix, stdout);
        printf("%s:%u | ", file, format.location.line());
        char buffer[512];
        formatBuffer(
            buffer, sizeof(buffer), format.format,
            Core::forward<Args>(args)...);
        fputs(buffer, stdout);
        puts(Terminal::RESET);
    }

    template<typename... Args>
    void logError(const FormatLocation& format, Args&&... args) {
        if constexpr(LOG_LEVEL >= 1) {
            char buffer[32];
            snprintf(buffer, sizeof(buffer), "%s[ERROR] ", Terminal::FG_RED);
            log(LogLevel::ERROR, buffer, format, forward<Args>(args)...);
        }
    }

    template<typename... Args>
    void logWarning(const FormatLocation& format, Args&&... args) {
        if constexpr(LOG_LEVEL >= 2) {
            char buffer[32];
            snprintf(
                buffer, sizeof(buffer), "%s[WARNING] ",
                Terminal::FG_BRIGHT_YELLOW);
            log(LogLevel::WARNING, buffer, format, forward<Args>(args)...);
        }
    }

    template<typename... Args>
    void logInfo(const FormatLocation& format, Args&&... args) {
        if constexpr(LOG_LEVEL >= 3) {
            char buffer[32];
            snprintf(buffer, sizeof(buffer), "%s[INFO] ", Terminal::BOLD);
            log(LogLevel::INFO, buffer, format, forward<Args>(args)...);
        }
    }

    template<typename... Args>
    void logDebug(const FormatLocation& format, Args&&... args) {
        if constexpr(LOG_LEVEL >= 4) {
            char buffer[32];
            snprintf(
                buffer, sizeof(buffer), "%s%s[DEBUG] ", Terminal::BOLD,
                Terminal::FG_BRIGHT_BLACK);
            log(LogLevel::DEBUG, buffer, format, forward<Args>(args)...);
        }
    }
}