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

public enum VisualTheme
{
    Default,
    EyeComfort
}

[Serializable]
public class VisualSpriteVariantPair
{
    public string Group;
    public Sprite Source;
    public Sprite EyeComfort;
}

[CreateAssetMenu(fileName = "VisualSpriteVariantMap", menuName = "TH1 Game Data/Visual Sprite Variant Map")]
public class VisualSpriteVariantMapAsset : ScriptableObject
{
    public List<VisualSpriteVariantPair> Pairs = new();

    [NonSerialized] private Dictionary<Sprite, Sprite> _eyeComfortDict;

    public Sprite Resolve(Sprite source, VisualTheme theme)
    {
        if (source == null || theme == VisualTheme.Default)
            return source;

        BuildDictIfNeeded();

        return _eyeComfortDict.TryGetValue(source, out var replacement) && replacement != null
            ? replacement
            : source;
    }

    public int CountMappedPairs(VisualTheme theme)
    {
        if (theme == VisualTheme.Default)
            return 0;

        int count = 0;
        foreach (var pair in Pairs)
        {
            if (pair?.Source != null && pair.EyeComfort != null)
                count++;
        }

        return count;
    }

    public void RebuildCache()
    {
        _eyeComfortDict = null;
        BuildDictIfNeeded();
    }

    private void BuildDictIfNeeded()
    {
        if (_eyeComfortDict != null)
            return;

        _eyeComfortDict = new Dictionary<Sprite, Sprite>();
        foreach (var pair in Pairs)
        {
            if (pair?.Source == null || pair.EyeComfort == null)
                continue;

            _eyeComfortDict[pair.Source] = pair.EyeComfort;
        }
    }

    private void OnValidate()
    {
        _eyeComfortDict = null;
    }
}