SaveGame.cs by Dicework Games

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System;

/*
 * SaveGame class. Replaces Unity's PlayerPrefs for saving game data.
 *
 * Uses Application.persistentDataPath for cross-platform compatibility.
 *
 * Can be used to replace PlayerPrefs directly, eg:
 * PlayerPrefs.SetInt("someInt", 1) -> SaveGame.SetInt("someInt", 1)
 *
 * © Arto Koistinen / Dicework Games 2012. Free for use.
 *
 */

public class SaveGame  {
    private static SaveGame _instance;

    private Hashtable saveData;

    private static SaveGame instance {
        get {
            if(_instance == null)
                new SaveGame();

            return _instance;
        }
    }

    private SaveGame() {
        _instance = this;
        saveData = new Hashtable();
    }

    public static void DeleteKey(string key) {
        instance.saveData.Remove(key);
    }

    public static void SetString(string key, string value) {
        if(instance.saveData[key] == null)
            instance.saveData.Add(key, value);
        else instance.saveData[key] = value;
    }

    public static void DeleteAll() {
        instance.saveData = new Hashtable();
    }

    public static void SetInt(string key, int value) {
        if(instance.saveData[key] == null)
            instance.saveData.Add(key, value);
        else instance.saveData[key] = value;
    }

    /// <summary>
    /// Loads the saveData hashtable from a file called "default.sav".
    /// </summary>
    public static void Load() {
        instance.saveData = (Hashtable) LoadFromFile("default.sav");

        if(instance.saveData == null)
            instance.saveData = new Hashtable();
    }

    /// <summary>
    /// Saves the saveData hashtable to a file called "default.sav".
    /// </summary>
    public static void Save() {
        SaveToFile(instance.saveData, "default.sav");
    }


    // if !DEBUG is just to prevent MonoDevelop from giving errors on the default value
#if !DEBUG
    public static string GetString(string key, string defaultValue = "") {
        if(instance.saveData[key] == null)
            return defaultValue;
        else return (string) instance.saveData[key];
    }

    public static int GetInt(string key, int defaultValue = 0) {
        if(instance.saveData[key] == null)
            return defaultValue;
        else return (int) instance.saveData[key];
    }
#endif

    // <summary>
    // Returns the save path. This is currently identical to Application.persistentDataPath.
    // </summary>
    // <returns>
    // A <see cref="System.String"/>
    // </returns>
    public static string GetPath() {
        string path = Application.persistentDataPath;
        // Debug.Log(path);
        return path;
    }

    // <summary>
    // Returns true if file exists in the save directory.
    // </summary>
    // <param name="filename">
    // A <see cref="System.String"/>
    // </param>
    // <returns>
    // A <see cref="System.Boolean"/>
    // </returns>
    public static bool Exists(string filename) {
        return File.Exists(GetPath() + "/" + filename);
    }

    /*
     *
     * Utility methods for SerializableDictionary. Uncomment if needed.
     *
    private static SerializableDictionary<string, SerializableDictionary<string,string>> ToSerializable( SerializableDictionary<string,  SerializableDictionary<string, string>> source) {
        SerializableDictionary<string, SerializableDictionary<string, string>> serializable = new SerializableDictionary<string, SerializableDictionary<string, string>>();

        foreach(string key in source.Keys) {
            serializable[key] = ToSerializable(source[key]);
        }

        return serializable;
    }

    private static SerializableDictionary<string, LevelData> ToSerializable( SerializableDictionary<string, LevelData> source) {
        SerializableDictionary<string, LevelData> serializable = new SerializableDictionary<string, LevelData>();

        foreach(string key in source.Keys) {
            serializable[key] = source[key];
        }

        return serializable;
    }

    private static SerializableDictionary<string, string> ToSerializable( SerializableDictionary<string, string> source) {
        SerializableDictionary<string, string> serializable = new SerializableDictionary<string, string>();

        foreach(string key in source.Keys) {
            serializable[key] = source[key];
        }

        return serializable;
    } */


    // <summary>
    // Saves a System.Object to a file. Can be used to save any (serializable) classes. Uses binary formatter to serialize the file.
    // </summary>
    // <param name="data">
    // A <see cref="System.Object"/>
    // </param>
    // <param name="filename">
    // A <see cref="System.String"/>
    // </param>
    public static void SaveToFile(System.Object data, string filename) {
        string path = GetPath();
        DirectoryInfo saveDirectory = new DirectoryInfo(path);

        if(!saveDirectory.Exists) {
            Debug.Log("Creating save directory");
            saveDirectory.Create();
        }

        Debug.Log("Saving data to: " + saveDirectory.FullName + "/" + filename);
        Stream stream = new FileStream(saveDirectory.FullName + "/" + filename, FileMode.Create, FileAccess.Write, FileShare.None);
        BinaryFormatter formatter = new BinaryFormatter();
        formatter.Serialize(stream, data);
        stream.Close();
    }

    // <summary>
    // Loads a System.Object from a file. Uses binary formatter to deserialize.
    // </summary>
    // <param name="filename">
    // A <see cref="System.String"/>
    // </param>
    // <returns>
    // A <see cref="System.Object"/>
    // </returns>

    public static System.Object LoadFromFile(string filename) {
        Debug.Log("Load From file " + filename);
        BinaryFormatter formatter = new BinaryFormatter();
        string path = GetPath();
        DirectoryInfo saveDirectory = new DirectoryInfo(path);

        if(!saveDirectory.Exists) {
            return null;
        }

        //FileInfo saveFile = saveDirectory.GetFile(filename);

        FileInfo[] files = saveDirectory.GetFiles("*.sav");
        string saveFile = null;

        foreach(FileInfo file in files) {
            if(file.Name == filename) {
                saveFile = file.FullName;
                break;
            }
        }

        if(saveFile == null) {
            Debug.LogWarning("Save file not found.");
            return null;
        }

        Stream stream = new FileStream(saveFile, FileMode.Open, FileAccess.Read, FileShare.None);

        if(stream == null) {
            return null;
        }

        if(stream.Length > 0) {
            System.Object data = formatter.Deserialize(stream);
            Debug.Log("Load successful!");
            return data;
        } else {
            Debug.LogWarning("Stream.Length = 0!");
            return null;
        }
    }
}