Improve code readability by simplifying debug logging

[dymanoid]

In the current code, there are a lot of such constructs:

#if DEBUG
    if (debug)
        Log._Debug("Whatever");
#endif

They are sometimes repeated very often, after each line (e.g. JunctionRestrictionsManager.cs).
It's almost impossible to read and to understand code like that.

Suggested improvements:

• The Log._Debug method already has the [Conditional("DEBUG")] attribute, so no need in #if DEBUG / #endif region at all
• The if (debug) check can actually be transferred into the Log._Debug method

After those improvements, the logging code becomes as simple as that:

        Log._Debug("Whatever");

It will make the code much more readable and won't affect performance.

[originalfoo]

And in cases where conditional declarations are required, for a single line, it's much cleaner to do:

[Conditional("DEBUG")]

I'll have a go at tidying up JunctionRestrictionsManager.cs

EDIT: But first need to work out what this means:

bool debug = GlobalConfig.Instance.Debug.Switches[11];

[originalfoo]

Ok, seems the switches toggle individual bits of the debug trace:

https://github.com/krzychu124/Cities-Skylines-Traffic-Manager-President-Edition/blob/master/TLM/TLM/State/ConfigData/Debug.cs#L23

Here's what I propose - add a switchId overload for the _Debug() method:

[Conditional("DEBUG")]
public static void _Debug(string s) {
        LogToFile(s, LogLevel.Debug);
}

[Conditional("DEBUG")]
public static void _Debug(uint switchId, string s) {
    if (GlobalConfig.Instance.Debug.Switches[switchId])
        LogToFile(s, LogLevel.Debug);
}

Using the overloaded method:

[Conditional("DEBUG")]
Log._Debug(11, "Whatever"); // eg. only debug if switch 11 is set

Even then the 11 is a magic number until you go digging. Why not just define a load of named boolean constants or something?

[originalfoo]

Ugh, Log.cs in CSUtil.Commons module so no access to TrafficManager.State...

[VictorPhilipp]

The logic of the debug flag often includes other debug parameters like SegmentId, NodeId, VehicleId, etc.

Suggestion: Don't use magic numbers. Create a TMLog class in the TLM project with individual Debug... methods for each debug condition. Make TMLog wrap Log.

Most important: Please wait until the harmony migration is complete since almost every change to the manager classes is causing merge conflicts.

[dymanoid]

@aubergine10: JunctionRestrictionsManager.cs was just an example, those #ifdef constructs are scattered across the whole solution. It would be really nice to improve all the usages, not only that class.

And you don't need this:

[Conditional("DEBUG")]
Log._Debug(11, "Whatever");

You need only this:

Log._Debug(11, "Whatever");

The Log._Debug method already has the [Conditional("DEBUG")] attribute. So it will only be called if DEBUG is defined. No need of additional stuff. Please read about that attribute in the docs.

@VictorPhilipp, consolidating the logging is a great idea!