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Source/Engine/Core/Log.h

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#include "Engine/Core/Singleton.h"
+#include "Engine/Core/Delegate.h"
+#include "Engine/Core/Types/String.h"
+#include "Engine/Core/Types/StringView.h"
+
+// Enable/disable auto flush function
+#define LOG_ENABLE_AUTO_FLUSH 1
+
+/// <summary>
+/// Sends a formatted message to the log file (message type - describes level of the log (see LogType enum))
+/// </summary>
+#define LOG(messageType, format, ...) Log::Logger::Write(LogType::messageType, TEXT(format), ##__VA_ARGS__)
+
+/// <summary>
+/// Sends a string message to the log file (message type - describes level of the log (see LogType enum))
+/// </summary>
+#define LOG_STR(messageType, str) Log::Logger::Write(LogType::messageType, str)
+
+#if LOG_ENABLE_AUTO_FLUSH
+// Flushes the log file buffer
+#define LOG_FLUSH() Log::Logger::Flush()
+#else
+#define LOG_FLUSH()
+#endif
+
+/// <summary>
+/// The log message types.
+/// </summary>
+API_ENUM() enum class LogType
+{
+    /// <summary>
+    /// The information log message.
+    /// </summary>
+    Info = 1,
+
+    /// <summary>
+    /// The warning message.
+    /// </summary>
+    Warning = 2,
+
+    /// <summary>
+    /// The error message.
+    /// </summary>
+    Error = 4,
+
+    /// <summary>
+    /// The fatal error.
+    /// </summary>
+    Fatal = 8,
+};
+
+extern const Char* ToString(LogType e);
+
+namespace Log
+{
+    class Exception;
+
+    /// <summary>
+    /// Singleton logger class
+    /// </summary>
+    /// <seealso cref="Singleton" />
+    class FLAXENGINE_API Logger : public Singleton<Logger>
+    {
+    public:
+
+        /// <summary>
+        /// Current log file path. Empty if not used.
+        /// </summary>
+        static String LogFilePath;
+
+        /// <summary>
+        /// Action fired on new log message.
+        /// </summary>
+        static Delegate<LogType, const StringView&> OnMessage;
+
+        /// <summary>
+        /// Action fired on new log error message.
+        /// </summary>
+        static Delegate<LogType, const StringView&> OnError;
+
+    public:
+
+        /// <summary>
+        /// Initializes a logging service.
+        /// </summary>
+        /// <returns>True if cannot init logging service, otherwise false.</returns>
+        static bool Init();
+
+        /// <summary>
+        /// Disposes a logging service.
+        /// </summary>
+        static void Dispose();
+
+    public:
+
+        FORCE_INLINE static bool IsError(const LogType type)
+        {
+            return type == LogType::Fatal || type == LogType::Error;
+        }
+
+    public:
+
+        /// <summary>
+        /// Determines whether logging to file is enabled.
+        /// </summary>
+        /// <returns><c>true</c> if log is enabled; otherwise, <c>false</c>.</returns>
+        static bool IsLogEnabled();
+
+        /// <summary>
+        /// Flushes log file with a memory buffer.
+        /// </summary>
+        static void Flush();
+
+        /// <summary>
+        /// Writes a series of '=' chars to the log to end a section.
+        /// </summary>
+        static void WriteFloor();
+
+        /// <summary>
+        /// Writes a message to the log file.
+        /// </summary>
+        /// <param name="type">The message type.</param>
+        /// <param name="msg">The message text.</param>
+        template<typename... Args>
+        FORCE_INLINE static void Write(LogType type, const Char* msg)
+        {
+            Write(type, StringView(msg));
+        }
+
+        /// <summary>
+        /// Writes a formatted message to the log file.
+        /// </summary>
+        /// <param name="type">The message type.</param>
+        /// <param name="format">The message format string.</param>
+        /// <param name="args">The format arguments.</param>
+        template<typename... Args>
+        FORCE_INLINE static void Write(LogType type, const Char* format, const Args& ... args)
+        {
+            Write(type, String::Format(format, args...));
+        }
+
+        /// <summary>
+        /// Write a message to the log.
+        /// </summary>
+        /// <param name="type">The message type.</param>
+        /// <param name="msg">The message text.</param>
+        static void Write(LogType type, const StringView& msg);
+
+        /// <summary>
+        /// Writes a custom message to the log.
+        /// </summary>
+        /// <param name="msg">The message text.</param>
+        FORCE_INLINE static void Write(const Char* msg)
+        {
+            Write(StringView(msg));
+        }
+
+        /// <summary>
+        /// Writes a custom message to the log.
+        /// </summary>
+        /// <param name="msg">The message text.</param>
+        FORCE_INLINE static void Write(const String& msg)
+        {
+            Write(StringView(msg));
+        }
+
+        /// <summary>
+        /// Writes a custom message to the log.
+        /// </summary>
+        /// <param name="msg">The message text.</param>
+        static void Write(const StringView& msg);
+
+        /// <summary>
+        /// Writes an exception formatted message to log file.
+        /// </summary>
+        /// <param name="exception">The exception to write to the file.</param>
+        static void Write(const Exception& exception);
+
+    private:
+
+        static void ProcessLogMessage(LogType type, const StringView& msg, fmt_flax::memory_buffer& w);
+    };
+}