using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Facepunch.Steamworks.Data;

namespace Facepunch.Steamworks
{
	/// <summary>
	/// A structured description of an item exchange
	/// </summary>
	public struct InventoryRecipe : IEquatable<InventoryRecipe>
	{
		public struct Ingredient
		{
			/// <summary>
			/// The definition ID of the ingredient.
			/// </summary>
			public int DefinitionId;

			/// <summary>
			/// If we don't know about this item definition this might be null.
			/// In which case, DefinitionId should still hold the correct id.
			/// </summary>
			public InventoryDef Definition;

			/// <summary>
			/// The amount of this item needed. Generally this will be 1.
			/// </summary>
			public int Count;

			internal static Ingredient FromString( string part )
			{
				var i = new Ingredient();
				i.Count = 1;

				try
				{
					if ( part.Contains( "x" ) )
					{
						var idx = part.IndexOf( 'x' );

						int count = 0;
						if ( int.TryParse( part.Substring( idx + 1 ), out count ) )
							i.Count = count;

						part = part.Substring( 0, idx );
					}

					i.DefinitionId = int.Parse( part );
					i.Definition = SteamInventory.FindDefinition( i.DefinitionId );

				}
				catch ( System.Exception )
				{
					return i;
				}

				return i;
			}
		}

		/// <summary>
		/// The item that this will create.
		/// </summary>
		public InventoryDef Result;

		/// <summary>
		/// The items, with quantity required to create this item.
		/// </summary>
		public Ingredient[] Ingredients;

		public string Source;

		internal static InventoryRecipe FromString( string part, InventoryDef Result )
		{
			var r = new InventoryRecipe
			{
				Result = Result,
				Source = part
			};

			var parts = part.Split( new[] { ',' }, StringSplitOptions.RemoveEmptyEntries );

			r.Ingredients = parts.Select( x => Ingredient.FromString( x ) ).Where( x => x.DefinitionId != 0 ).ToArray();
			return r;
		}

		internal bool ContainsIngredient( InventoryDef inventoryDef )
		{
			return Ingredients.Any( x => x.DefinitionId == inventoryDef.Id );
		}

		public static bool operator ==( InventoryRecipe a, InventoryRecipe b ) => a.GetHashCode() == b.GetHashCode();
		public static bool operator !=( InventoryRecipe a, InventoryRecipe b ) => a.GetHashCode() != b.GetHashCode();
		public override bool Equals( object p ) => this.Equals( (InventoryRecipe)p );
		public override int GetHashCode()
		{
			return Source.GetHashCode();
		}

		public bool Equals( InventoryRecipe p ) => p.GetHashCode() == GetHashCode();
	}
}