using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEngine.UIElements;

public class StoredResource
{
    public Resource Resource { get; private set; }
    public int Amount { get; internal set; }
    public bool Unlocked { get; internal set; }

    public StoredResource(Resource resource)
    {
        Resource = resource;
        Amount = 0;
        Unlocked = false;
    }
}

public class ResourceStorage : MonoBehaviour
{
    public static ResourceStorage Instance { get; private set; }

    private Dictionary<string, StoredResource> resources = new Dictionary<string, StoredResource>();

    private List<Action> changeCallbacks = new List<Action>();

    public static readonly Metal Metal = new Metal();
    public static readonly Electronics Electronics = new Electronics();
    public static readonly Energy Energy = new Energy();
    public static readonly Money Money = new Money();

    public static Resource[] RegisteredResources
    {
        get
        {
            var list = new List<Resource>();
            list.Add(Metal);
            list.Add(Electronics);
            list.Add(Energy);
            list.Add(Money);

            return list.ToArray();
        }
    }

    public static Type[] RegisteredResourceTypes =>
        RegisteredResources.Select(r => r.GetType()).ToArray();

    public ResourceStorage()
    {
        AddResource(Metal, true);
        AddResource(Electronics, true); // TODO lock back
        AddResource(Energy, true); // TODO lock back
        AddResource(Money, true); // TODO lock back

        Instance = this;
    }

    private void AddResource(Resource resource, bool unlocked = false)
    {
        resources.Add(resource.Name, new StoredResource(resource) { Unlocked = unlocked });
    }

    public StoredResource GetResource(Resource resource)
    {
        return resources[resource.Name];
    }

    public void AddResource(Resource resource, int amount)
    {
        var res = GetResource(resource);
        if (res != null)
        {
            res.Amount += amount;
            InvokeOnChange();
        }
    }

    public void RemoveResource(Resource resource, int amount)
    {
        var res = GetResource(resource);
        if (res != null && res.Amount >= amount)
        {
            res.Amount -= amount;
            InvokeOnChange();
        }
    }

    public void UnlockResource(Resource resource)
    {
        var res = GetResource(resource);
        if (res != null)
        {
            res.Unlocked = true;
            InvokeOnChange();
        }
    }

    private void InvokeOnChange()
    {
        // Debug.Log(
        //     $"Resources: {String.Join("; ", resources.Values.ToArray().Select(r => r.Resource.Name + "=" + r.Amount + (r.Unlocked ? "" : "(locked)")))}"
        // );

        changeCallbacks.ForEach(a =>
        {
            try
            {
                a.Invoke();
            }
            catch { }
        });
    }

    public void RegisterOnChangeCallback(Action callback)
    {
        changeCallbacks.Add(callback);
    }

    public void UnregisterOnChangeCallback(Action callback)
    {
        changeCallbacks.Remove(callback);
    }
}