using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;

#if UNITY_EDITOR
using UnityEditor; // Needed to access SceneAsset in the editor
#endif

public class LevelManager : MonoBehaviour
{
    // A serializable structure that holds a UI button and its corresponding scene
    [System.Serializable]
    public class LevelEntry
    {
        public Button levelButton; // UI Button assigned in the inspector

#if UNITY_EDITOR
        public SceneAsset levelScene; // Reference to a .unity file, editable in the Inspector (Editor only)
#endif

        [HideInInspector]
        public string sceneName; // Runtime scene name used for loading (stored automatically)
    }

    // A list of LevelEntry objects that can be filled in the inspector
    public List<LevelEntry> levels = new List<LevelEntry>();

    // Called when the GameObject is first initialized (before Start)
    private void Awake()
    {
#if UNITY_EDITOR
        // In the editor, we convert SceneAsset references into usable scene names
        foreach (var entry in levels)
        {
            if (entry.levelScene != null)
            {
                // Get the full path to the scene asset
                entry.sceneName = AssetDatabase.GetAssetPath(entry.levelScene);

                // Extract only the scene name (e.g., "Level1" from "Assets/Scenes/Level1.unity")
                entry.sceneName = System.IO.Path.GetFileNameWithoutExtension(entry.sceneName);
            }
        }
#endif

        // Loop through each level entry and hook up the button to load the correct scene
        foreach (var entry in levels)
        {
            // Check if both the button and scene name are set
            if (entry.levelButton != null && !string.IsNullOrEmpty(entry.sceneName))
            {
                // Store the scene name locally to avoid closure issues in the lambda
                string sceneToLoad = entry.sceneName;

                // Add an onClick listener that loads the correct scene when the button is clicked
                entry.levelButton.onClick.AddListener(() => LoadLevel(sceneToLoad));
            }
        }
    }

    // This method is called when a button is clicked, and loads the given scene by name
    public void LoadLevel(string sceneName)
    {
        SceneManager.LoadScene(sceneName); // Load the scene using Unity’s SceneManager
    }
}