using System;
using System.Collections.Generic;
using System.Linq;
using PkmnLibSharp.FFI;
using PkmnLibSharp.Utils;
using Interface = PkmnLibSharp.FFI.StaticData.Item;

namespace PkmnLibSharp.StaticData
{
    /// <summary>
    /// An item category defines which bag slot items are stored in.
    /// </summary>
    public enum ItemCategory : byte
    {
        /// <summary>
        /// This is where most items should go.
        /// </summary>
        MiscItem,

        /// <summary>
        /// Pokeballs are used for capturing Pokemons.
        /// </summary>
        Pokeball,

        /// <summary>
        /// Medicine is used for healing HP, PP, and status effects
        /// </summary>
        Medicine,

        /// <summary>
        /// Berry is used for all berries.
        /// </summary>
        Berry,

        /// <summary>
        /// TMHM is used for Technical and Hidden Machines.
        /// </summary>
        TMHM,

        /// <summary>
        /// Form Changer is used for items that change forms, such as mega stones.
        /// </summary>
        FormChanger,

        /// <summary>
        /// Key Items are single stored items, generally used for story progression.
        /// </summary>
        KeyItem,

        /// <summary>
        /// Mail is used for mail items.
        /// </summary>
        Mail,
    }

    /// <summary>
    /// A battle item category defines how the item is categorized when in battle.
    /// </summary>
    public enum BattleItemCategory : byte
    {
        /// <summary>
        /// This item can't be used in battle.
        /// </summary>
        None,

        /// <summary>
        /// This item is used for healing Pokemon.
        /// </summary>
        Healing,

        /// <summary>
        /// This item is used for healing Pokemon from a status.
        /// </summary>
        StatusHealing,

        /// <summary>
        /// This item is used for capturing Pokemon.
        /// </summary>
        Pokeball,

        /// <summary>
        /// This item does not belong in above categories, but is still a battle item.
        /// </summary>
        MiscBattleItem,
    }

    public class Item : ExternPointer<Item.CacheData>
    {
        public class CacheData
        {
            public string? Name { get; internal set; }
            public ItemCategory? Category { get; internal set; }
            public BattleItemCategory? BattleCategory { get; internal set; }
            public int? Price { get; internal set; }
        }

        public Item(string name, ItemCategory category, BattleItemCategory battleItemCategory, int price,
            IEnumerable<string> flags)
        {
            var ptrArray = flags.Select(x => x.ToPtr()).ToArray();
            var ptrToPtrArray = ptrArray.ArrayPtr();
            var ptr = Interface.item_new(name.ToPtr(), category, battleItemCategory, price, ptrToPtrArray,
                (ulong)ptrArray.Length);
            InitializePointer(ptr, true);
        }

        internal Item(IdentifiablePointer ptr) : base(ptr, true)
        {
        }

        public string Name => Cache.Name ??= Interface.item_name(Ptr).PtrString()!;
        public ItemCategory Category => Cache.Category ??= Interface.item_category(Ptr);
        public BattleItemCategory BattleCategory => Cache.BattleCategory ??= Interface.item_battle_category(Ptr);
        public int Price => Cache.Price ??= Interface.item_price(Ptr);

        public bool HasFlag(string flag) => Interface.item_has_flag(Ptr, flag.ToPtr()) == 1;

        protected override CacheData CreateCache() => new CacheData();
        protected override void Destructor() => Interface.item_drop(Ptr);
        
        ~Item()
        {
            Dispose();
        }
    }
}