ScoreManager.cs

 I've created a complete score management system for Unity! Here's what's included:

ScoreManager.cs - The main system featuring:

• Current score tracking
• Automatic high score saving (uses PlayerPrefs)
• Previous score storage
• Singleton pattern for easy access
• Event system for UI updates

ScoreUI.cs - UI display script that:

• Automatically updates when scores change
• Works with both TextMeshPro and legacy Unity Text
• Customizable text prefixes

GameExample.cs - Example implementation showing how to use the system in your game

using UnityEngine;
using System;

public class ScoreManager : MonoBehaviour
{
    // Singleton instance
    public static ScoreManager Instance { get; private set; }

    // Current game session scores
    private int currentScore = 0;
    private int previousScore = 0;

    // High score (persisted)
    private int highScore = 0;

    // Events for UI updates
    public event Action OnScoreChanged;
    public event Action OnHighScoreChanged;

    // PlayerPrefs keys
    private const string HIGH_SCORE_KEY = "HighScore";

    private void Awake()
    {
        // Singleton pattern
        if (Instance == null)
        {
            Instance = this;
            DontDestroyOnLoad(gameObject);
            LoadHighScore();
        }
        else
        {
            Destroy(gameObject);
        }
    }

    /// 

    /// Add points to the current score
    /// 
    public void AddScore(int points)
    {
        currentScore += points;
        OnScoreChanged?.Invoke(currentScore);
        CheckHighScore();
    }

    /// 

    /// Set the score to a specific value
    /// 
    public void SetScore(int score)
    {
        currentScore = score;
        OnScoreChanged?.Invoke(currentScore);
        CheckHighScore();
    }

    /// 

    /// Reset the current score (call this at the start of a new game)
    /// 
    public void ResetScore()
    {
        previousScore = currentScore;
        currentScore = 0;
        OnScoreChanged?.Invoke(currentScore);
    }

    /// 

    /// Check if current score is a new high score and update if needed
    /// 
    private void CheckHighScore()
    {
        if (currentScore > highScore)
        {
            highScore = currentScore;
            SaveHighScore();
            OnHighScoreChanged?.Invoke(highScore);
        }
    }

    /// 

    /// Save high score to PlayerPrefs
    /// 
    private void SaveHighScore()
    {
        PlayerPrefs.SetInt(HIGH_SCORE_KEY, highScore);
        PlayerPrefs.Save();
    }

    /// 

    /// Load high score from PlayerPrefs
    /// 
    private void LoadHighScore()
    {
        highScore = PlayerPrefs.GetInt(HIGH_SCORE_KEY, 0);
    }

    /// 

    /// Manually reset the high score (useful for testing or reset button)
    /// 
    public void ResetHighScore()
    {
        highScore = 0;
        SaveHighScore();
        OnHighScoreChanged?.Invoke(highScore);
    }

    // Getters
    public int GetCurrentScore() => currentScore;
    public int GetHighScore() => highScore;
    public int GetPreviousScore() => previousScore;

    /// 

    /// Check if the current score is a new high score
    /// 
    public bool IsNewHighScore()
    {
        return currentScore >= highScore && currentScore > 0;
    }
}