GameJamDungeon/Zennysoft.Game.Ma/src/items/ItemDatabase.cs

using Godot;
using System;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using Zennysoft.Ma.Adapter;

namespace Zennysoft.Game.Ma;

public class ItemDatabase
{
  private static readonly Lazy<ItemDatabase> lazy =
      new Lazy<ItemDatabase>(() => new ItemDatabase());

  public static ItemDatabase Instance { get { return lazy.Value; } }

  public ImmutableList<InventoryItem> Items { get; set; }

  public T PickItem<T>(T itemToExclude = null)
    where T : InventoryItem
  {
    var itemsToSelectFrom = Items;
    return PickItemInternal(itemsToSelectFrom, itemToExclude);
  }

  public T PickRareItem<T>(T itemToExclude = null)
    where T : InventoryItem
  {
    var getRareItems = Items.Where(x => x.SpawnRate < 0.1f);
    return PickItemInternal(getRareItems, itemToExclude);
  }

  public T PickBasicItem<T>(T itemToExclude = null)
    where T : InventoryItem
  {
    var getBasicItems = Items.Where(x => x.SpawnRate > 0.5f);
    return PickItemInternal(getBasicItems, itemToExclude);
  }

  private T PickItemInternal<T>(IEnumerable<InventoryItem> itemsToSelectFrom, T itemToExclude = null)
      where T : InventoryItem
  {
    var rng = new RandomNumberGenerator();
    rng.Randomize();

    if (itemToExclude is not null)
      itemsToSelectFrom = [.. itemsToSelectFrom.OfType<T>().Where(x => x.ItemName != itemToExclude.ItemName)];

    var weights = itemsToSelectFrom.Select(x => x.SpawnRate).ToArray();
    var selectedItem = itemsToSelectFrom.ToArray()[rng.RandWeighted(weights)];

    if (selectedItem is ThrowableItem throwableItem)
      throwableItem.SetCount(rng.RandiRange(throwableItem.Stats.MinimumCount, throwableItem.Stats.MaximumCount));

    return (T)selectedItem;
  }

  private ItemDatabase()
  {
    var database = new List<InventoryItem>();
    var armorResources = DirAccess.GetFilesAt("res://src/items/armor/resources/");
    var weaponResources = DirAccess.GetFilesAt("res://src/items/weapons/resources/");
    var accessoryResources = DirAccess.GetFilesAt("res://src/items/accessory/resources/");
    var throwableResources = DirAccess.GetFilesAt("res://src/items/throwable/resources/");
    var consumableResources = DirAccess.GetFilesAt("res://src/items/consumable/resources/");
    var effectResources = DirAccess.GetFilesAt("res://src/items/effect/resources/");

    foreach (var armor in armorResources)
    {
      var armorInfo = GD.Load<ArmorStats>($"res://src/items/armor/resources/{armor}");
      var armorScene = ResourceLoader.Load<PackedScene>("res://src/items/armor/Armor.tscn").Instantiate<Armor>();
      armorScene.Stats = armorInfo;
      if (!database.Contains(armorScene))
        database.Add(armorScene);
    }

    foreach (var weapon in weaponResources)
    {
      var weaponInfo = GD.Load<WeaponStats>($"res://src/items/weapons/resources/{weapon}");
      var weaponScene = ResourceLoader.Load<PackedScene>("res://src/items/weapons/Weapon.tscn").Instantiate<Weapon>();
      weaponScene.Stats = weaponInfo;
      if (!database.Contains(weaponScene))
        database.Add(weaponScene);
    }

    foreach (var accessory in accessoryResources)
    {
      var accessoryInfo = GD.Load<AccessoryStats>($"res://src/items/accessory/resources/{accessory}");
      var accessoryScene = ResourceLoader.Load<PackedScene>("res://src/items/accessory/Accessory.tscn").Instantiate<Accessory>();
      accessoryScene.Stats = accessoryInfo;
      if (!database.Contains(accessoryScene))
        database.Add(accessoryScene);
    }

    foreach (var throwable in throwableResources)
    {
      var throwableItemInfo = GD.Load<ThrowableItemStats>($"res://src/items/throwable/resources/{throwable}");
      var throwableItemScene = ResourceLoader.Load<PackedScene>("res://src/items/throwable/ThrowableItem.tscn").Instantiate<ThrowableItem>();
      throwableItemScene.Stats = throwableItemInfo;
      if (!database.Contains(throwableItemScene))
        database.Add(throwableItemScene);
    }

    foreach (var consumable in consumableResources)
    {
      var consumableItemInfo = GD.Load<ConsumableItemStats>($"res://src/items/consumable/resources/{consumable}");
      var consumableItemScene = ResourceLoader.Load<PackedScene>("res://src/items/consumable/ConsumableItem.tscn").Instantiate<ConsumableItem>();
      consumableItemScene.Stats = consumableItemInfo;
      if (!database.Contains(consumableItemScene))
        database.Add(consumableItemScene);
    }

    foreach (var effectItem in effectResources)
    {
      var effectItemInfo = GD.Load<EffectItemStats>($"res://src/items/effect/resources/{effectItem}");
      var effectItemScene = ResourceLoader.Load<PackedScene>("res://src/items/effect/EffectItem.tscn").Instantiate<EffectItem>();
      effectItemScene.Stats = effectItemInfo;
      if (!database.Contains(effectItemScene))
        database.Add(effectItemScene);
    }

    Items = [.. database];
  }
}