Add a base JsonFile implementation for extension, as well as a SaveDataCache extension of JsonFile for working with per-mod-per-saveslot cached data

[toebeann]

Changes made in this pull request

• Adds a basic JsonFile abstract implementation of IJsonFile, to alow easy extension in a similar manner to how ConfigFile operates.
• Adds a base SaveDataCache abstract extension of JsonFile, which is intended to be used as a per-mod-per-saveslot data cache. Multiple can be used per mod. It automatically generates the file path based on the game's SaveLoadManager.GetTemporaryStoragePath() and the SaveDataCache's defining QMod, i.e.:
  Subnautica\TempSave\tmp964151\SMLHelperExampleMod\player_position.json.
  This data will be moved into/out of deep storage as per normal, whenever the game is saved and loaded.
• Adds a SaveDataHandler, which allows an API consumer to easily register a SaveDataCache to be automatically loaded and saved when appropriate.
• To facilitate SaveDataHandler auto-loading the SaveDataCache files, adds public methods to the InGameMenuHandler: RegisterOnLoadEvent, UnregisterOnLoadEvent and RegisterOneTimeUseOnLoadEvent as companions to the methods already provided, which trigger when the game loads into the "Main" scene.
• Updated ExampleMod to show a basic usage of SaveDataCache.

Examples

JsonFile

public class MyJsonFile : JsonFile
{
    private static IQMod qMod;
    private static IQMod QMod => qMod ??= QModServices.Main.GetMyMod();

    public override string JsonFilePath => Path.Combine(Path.GetDirectoryName(QMod.LoadedAssembly.Location),
                                                        "my_json_file.json");

    public string MyString { get; set; }
}

[QModCore]
public static class Main
{
    [QModPatch]
    public static void Patch()
    {
        MyJsonFile json = new MyJsonFile();
        json.Load();
        json.MyString = "foo";
        json.Save();
    }
}

SaveDataCache

/// <summary>
/// A simple SaveDataCache implementation, intended to save the players current position to disk.
/// </summary>
[FileName("player_position")]
internal class SaveData : SaveDataCache
{
    public Vector3 PlayerPosition { get; set; }
}

[QModCore]
public static class Main
{
    [QModPatch]
    public static void Patch()
    {
        /// Works like ConfigFile - it will be automatically saved/loaded to/from disk appropriately,
        /// with its members updated whenever the user switches between save slots.
        SaveData saveData = SaveDataHandler.Main.RegisterSaveDataCache<SaveData>();

        // Simply display the recorded player position whenever the save data is loaded
        saveData.OnFinishedLoading += (object sender, JsonFileEventArgs e) =>
        {
            SaveData data = e.Instance as SaveData; // e.Instance is the instance of your SaveData stored as a JsonFile.
                                                    // We can use polymorphism to convert it back into a SaveData
                                                    // instance, and access its members, such as PlayerPosition.

            Logger.Log(Logger.Level.Info, 
                       $"loaded player position from save slot: {data.PlayerPosition}", 
                       showOnScreen: true);
        };

        // Update the player position before saving it
        saveData.OnStartedSaving += (object sender, JsonFileEventArgs e) =>
        {
            SaveData data = e.Instance as SaveData;
            data.PlayerPosition = Player.main.transform.position;
        };

        // Simply display the position we recorded to the save file whenever the save data it is saved
        saveData.OnFinishedSaving += (object sender, JsonFileEventArgs e) =>
        {
            SaveData data = e.Instance as SaveData;
            Logger.Log(Logger.Level.Info, 
                       $"saved player position to save slot: {data.PlayerPosition}", 
                       showOnScreen: true);
        };
    }
}

JsonFile implementations, similar to ConfigFile, have public OnStartedLoading/OnFinishedLoading & OnStartedSaving/OnFinishedSaving events, and since SaveDataCache extends JsonFile, you can easily hook up to these events if you need to react to the save/loads and do a bunch of processing, for example spawning in items in the correct locations.

Like with ConfigFile, it is entirely possible to use SaveDataCache without using the SaveDataHandler, but you will be responsible for handling when to save and load the data yourself.

If no FileNameAttribute is provided, the default filename is the QMod's id.

Builds a3634f5

Subnautica

Stable

SMLHelper
Example Mod

Experimental

SMLHelper
Example Mod

Below Zero

Stable

SMLHelper Zero
Example Mod

Experimental

SMLHelper Zero
Example Mod

[toebeann]

Builds 4545eab

Subnautica

Stable

SMLHelper
ExampleMod tracking the Player position as per the above example and storing it in player_position.json

Experimental

SMLHelper
ExampleMod tracking the Player position as per the above example and storing it in player_position.json

Below Zero

Stable

SMLHelper Zero
ExampleMod tracking the Player position as per the above example and storing it in player_position.json

Experimental

SMLHelper Zero
ExampleMod tracking the Player position as per the above example and storing it in player_position.json

[toebeann]

Builds b2479a6

Subnautica

Stable

SMLHelper
Example Mod

Experimental

SMLHelper
Example Mod

Below Zero

Stable

SMLHelper Zero
Example Mod

Experimental

SMLHelper Zero
Example Mod

[toebeann]

Builds a3634f5

Subnautica

Stable

SMLHelper
Example Mod

Experimental

SMLHelper
Example Mod

Below Zero

Stable

SMLHelper Zero
Example Mod

Experimental

SMLHelper Zero
Example Mod

[MrPurple6411]

Looks useful, Builds on all branches, Example mod loads and saved player position on save, Doesnt seem to break my 136 mod loadout. I think it works 👍🏻