using System.Diagnostics;

namespace SimpleHttpServer;
public class Logger {
    private readonly string topic;
    private readonly LogOutputTopic ltopic;
    private readonly bool printToConsole;
    private readonly SimpleHttpServerConfiguration.CustomLogMessageHandler? externalLogMsgHandler;

    internal Logger(LogOutputTopic topic, SimpleHttpServerConfiguration conf) {
        this.topic = Enum.GetName(topic) ?? throw new ArgumentException("The given LogOutputTopic is not defined!");
        ltopic = topic;
        externalLogMsgHandler = conf.LogMessageHandler;
        printToConsole = !conf.DisableLogMessagePrinting;
    }

    private readonly object writeLock = new();
    public void Log(string message, LogOutputLevel level) {
        var fgColor = level switch {
            LogOutputLevel.Debug => ConsoleColor.Gray,
            LogOutputLevel.Information => ConsoleColor.White,
            LogOutputLevel.Warning => ConsoleColor.Yellow,
            LogOutputLevel.Error => ConsoleColor.Red,
            LogOutputLevel.Fatal => ConsoleColor.Magenta,
            _ => throw new NotImplementedException(),
        };

        if (printToConsole)
            lock (writeLock) {
                var origColor = Console.ForegroundColor;
                Console.ForegroundColor = fgColor;
                Console.WriteLine($"[{topic}] {message}");
                Console.ForegroundColor = origColor;
            }

        externalLogMsgHandler?.Invoke(ltopic, message, level);
    }

    [Conditional("DEBUG")]
    public void Debug(string message) => Log(message, LogOutputLevel.Debug);
    public void Information(string message) => Log(message, LogOutputLevel.Information);
    public void Warning(string message) => Log(message, LogOutputLevel.Warning);
    public void Error(string message) => Log(message, LogOutputLevel.Error);
    public void Fatal(string message) => Log(message, LogOutputLevel.Fatal);

}

public enum LogOutputLevel {
    Debug,
    Information,
    Warning,
    Error,
    Fatal
}

public enum LogOutputTopic {
    Main,
    Request,
    Security
}