using UnityEngine;
using System.Collections.Generic;
using System;

/// <summary>
/// ScriptableObject representing a single puzzle step, its display info, and which steps it unlocks.
/// </summary>
[CreateAssetMenu(fileName = "PuzzleStepSO", menuName = "AppleHills/Items & Puzzles/Step")]
public class PuzzleStepSO : ScriptableObject
{
    /// <summary>
    /// Unique identifier for this puzzle step.
    /// </summary>
    public string stepId;
    /// <summary>
    /// Display name for this step.
    /// </summary>
    public string displayName;
    /// <summary>
    /// Description of this step.
    /// </summary>
    [TextArea]
    public string description;
    /// <summary>
    /// Icon for this step.
    /// </summary>
    public Sprite icon;
    /// <summary>
    /// List of steps that this step unlocks when completed.
    /// </summary>
    [Header("Unlocks")]
    public List<PuzzleStepSO> unlocks = new List<PuzzleStepSO>();
    
    /// <summary>
    /// Override Equals to compare by stepId rather than reference equality.
    /// This ensures consistent behavior across different platforms (Editor vs Mobile).
    /// </summary>
    /// <param name="obj">Object to compare to</param>
    /// <returns>True if the objects represent the same puzzle step</returns>
    public override bool Equals(object obj)
    {
        if (obj == null) return false;
        
        // Check if the object is actually a PuzzleStepSO
        PuzzleStepSO other = obj as PuzzleStepSO;
        if (other == null) return false;
        
        // Compare by stepId instead of reference
        return string.Equals(stepId, other.stepId, StringComparison.Ordinal);
    }
    
    /// <summary>
    /// Override GetHashCode to be consistent with the Equals method.
    /// This is crucial for HashSet and Dictionary to work properly.
    /// </summary>
    /// <returns>Hash code based on stepId</returns>
    public override int GetHashCode()
    {
        // Generate hash code from stepId to ensure consistent hashing
        return stepId != null ? stepId.GetHashCode() : 0;
    }
    
    /// <summary>
    /// Override == operator to use our custom equality logic
    /// </summary>
    public static bool operator ==(PuzzleStepSO a, PuzzleStepSO b)
    {
        // Check if both are null or if they're the same instance
        if (ReferenceEquals(a, b))
            return true;
            
        // Check if either is null (but not both, as that's handled above)
        if (((object)a == null) || ((object)b == null))
            return false;
            
        // Use our custom Equals method
        return a.Equals(b);
    }
    
    /// <summary>
    /// Override != operator to be consistent with == operator
    /// </summary>
    public static bool operator !=(PuzzleStepSO a, PuzzleStepSO b)
    {
        return !(a == b);
    }
}