1 files changed, 156 insertions, 0 deletions
diff --git a/src/core/log.h b/src/core/log.h
new file mode 100644
index 0000000..db6b4b4
--- /dev/null
+++ b/src/core/log.h
@@ -0,0 +1,156 @@
+#pragma once
+
+#include "core/memory.h"
+
+#include <string>
+#include <vector>
+#include <sstream>
+#include <iostream>
+#include <fstream>
+#include <chrono>
+#include <iomanip>
+#include <mutex>
+#include <string_view>
+
+namespace Donut
+{
+    enum class LogLevel
+    {
+        trace = 0,
+        Info  = 2,
+        Warn  = 3,
+        Err   = 4,
+        Fatal = 5
+    };
+
+    class Logger
+    {
+    public:
+        Logger();
+        ~Logger();
+
+        static auto init() -> void;
+        static auto shutdown() -> void;
+
+        static auto get_logger() -> Ref<Logger>;
+
+        template<typename... Args>
+        static auto trace(const std::string_view& format, const Args&... args) -> void
+        {
+            auto logger = get_logger();
+            if (logger) logger->log_message(LogLevel::trace, format, args...);
+        }
+
+        template<typename... Args>
+        static auto info(const std::string_view& format, const Args&... args) -> void
+        {
+            auto logger = get_logger();
+            if (logger) logger->log_message(LogLevel::Info, format, args...);
+        }
+
+        template<typename... Args>
+        static auto warn(const std::string_view& format, const Args&... args) -> void
+        {
+            auto logger = get_logger();
+            if (logger) logger->log_message(LogLevel::Warn, format, args...);
+        }
+
+        template<typename... Args>
+        static auto error(const std::string_view& format, const Args&... args) -> void
+        {
+            auto logger = get_logger();
+            if (logger) logger->log_message(LogLevel::Err, format, args...);
+        }
+
+        template<typename... Args>
+        static auto fatal(const std::string_view& format, const Args&... args) -> void
+        {
+            auto logger = get_logger();
+            if (logger) logger->log_message(LogLevel::Fatal, format, args...);
+        }
+
+        template<typename... Args>
+        auto log_message(LogLevel level, const std::string_view& format, const Args&... args) -> void
+        {
+            if (level < m_log_level)
+                return;
+
+            std::lock_guard<std::mutex> lock(m_mutex);
+            std::string message = format_string(format, args...);
+            std::string full_message = get_time_stamp() + " [" + get_log_level_string(level) + "] " + message;
+
+            if (m_console_output)
+            {
+                set_console_color(level);
+                std::cout << full_message << std::endl;
+                reset_console_color();
+            }
+
+            if (m_file_output && m_log_file.is_open())
+            {
+                m_log_file << full_message << std::endl;
+                m_log_file.flush();
+            }
+        }
+
+        template<typename... Args>
+        auto format_string(const std::string_view& format, const Args&... args) -> std::string
+        {
+            std::string result = format.data();
+            std::vector<std::string> arg_strings = { to_string(args)... };
+
+            size_t arg_index = 0;
+            size_t pos = 0;
+
+            while ((pos = result.find("{}", pos)) != std::string::npos && arg_index < arg_strings.size())
+            {
+                result.replace(pos, 2, arg_strings[arg_index]);
+                pos += arg_strings[arg_index].length();
+                arg_index++;
+            }
+
+            return result;
+        }
+
+        template<typename T>
+        auto to_string(const T& value) -> std::string
+        {
+            std::stringstream ss;
+            ss << value;
+            return ss.str();
+        }
+
+        auto set_log_level(LogLevel level) -> void      { m_log_level      = level;  }
+        auto enable_console_output(bool enable) -> void { m_console_output = enable; }
+        auto enable_file_output(bool enable) -> void    { m_file_output    = enable; }
+        auto set_log_file(const std::string& filename) -> void;
+
+        auto get_time_stamp() -> std::string;
+        auto get_log_level_string(LogLevel level) -> std::string;
+        auto set_console_color(LogLevel level) -> void;
+        auto reset_console_color() -> void;
+
+    private:
+        LogLevel      m_log_level;
+        bool          m_console_output;
+        bool          m_file_output;
+        std::ofstream m_log_file;
+        std::mutex    m_mutex;
+
+        static Ref<Logger> s_logger;
+    };
+}
+
+#if defined(DONUT_DEBUG)
+    #define DONUT_TRACE(format, ...)    ::Donut::Logger::trace(format, ##__VA_ARGS__)
+    #define DONUT_INFO(format, ...)     ::Donut::Logger::info(format, ##__VA_ARGS__)
+    #define DONUT_WARN(format, ...)     ::Donut::Logger::warn(format, ##__VA_ARGS__)
+    #define DONUT_ERROR(format, ...)    ::Donut::Logger::error(format, ##__VA_ARGS__)
+    #define DONUT_FATAL(format, ...)    ::Donut::Logger::fatal(format, ##__VA_ARGS__)
+#else
+    #define DONUT_TRACE(format, ...)    {}
+    #define DONUT_INFO(format, ...)     {}
+    #define DONUT_WARN(format, ...)     {}
+    #define DONUT_ERROR(format, ...)    {}
+    #define DONUT_FATAL(format, ...)    {}
+#endif