using System;
using System.Collections.Generic;
using System.IO;
using IronMountain.SaveSystem;

namespace SpellBoundAR.Items.Inventories
{
    public class SavedInventory : IInventory
    {
        public event Action OnEntriesChanged;

        private string _directory = string.Empty;
        
        public string ID { get; }

        public string Directory
        {
            get => _directory;
            set
            {
                if (_directory == value) return;
                _directory = value;
                ReloadEntries();
            }
        }

        private readonly List<IInventoryEntry> _entries = new ();

        public List<IInventoryEntry> GetAllEntries() => _entries;

        public IInventoryEntry GetEntry(IItemTypeData itemTypeData)
        {
            if (itemTypeData == null) return null;
            foreach (IInventoryEntry entry in _entries)
            {
                if (entry?.ItemTypeData == null) continue;
                if (entry.ItemTypeData == itemTypeData 
                    || entry.ItemTypeData.ID == itemTypeData.ID) return entry;
            }
            return null;
        }

        public virtual void Add(IItemTypeData itemTypeData, int quantity)
        {
            if (itemTypeData == null) return;
            IInventoryEntry entry = GetEntry(itemTypeData);
            if (entry == null)
            {
                _entries.Add(new SavedInventoryEntry(
                    Path.Combine(Directory, Guid.NewGuid().ToString()),
                    itemTypeData,
                    quantity,
                    0
                ));
                OnEntriesChanged?.Invoke();
            }
            else entry.Quantity += quantity;
            IInventory.InvokeOnAnyInventoryChanged(this, itemTypeData);
        }
    
        public virtual void Remove(IItemTypeData itemTypeData, int amount) 
        {
            if (itemTypeData == null) return;
            IInventoryEntry entry = GetEntry(itemTypeData);
            if (entry == null) return;
            entry.Quantity -= amount;
            if (entry.Quantity == 0 && entry is SavedInventoryEntry savedInventoryEntry)
            {
                _entries.Remove(entry);
                SaveSystem.DeleteDirectory(savedInventoryEntry.Directory);
                OnEntriesChanged?.Invoke();
            }
            IInventory.InvokeOnAnyInventoryChanged(this, itemTypeData);
        }

        public virtual void RemoveAll(IItemTypeData itemTypeData)
        {
            if (itemTypeData == null) return;
            IInventoryEntry entry = GetEntry(itemTypeData);
            if (entry == null) return;
            entry.Quantity = 0;
            _entries.Remove(entry);
            if (entry is SavedInventoryEntry savedInventoryEntry)
            {
                SaveSystem.DeleteDirectory(savedInventoryEntry.Directory);
            }
            OnEntriesChanged?.Invoke();
            IInventory.InvokeOnAnyInventoryChanged(this, itemTypeData);
        }

        public virtual void Clear()
        {
            _entries.Clear();
            DirectoryInfo[] directoryList = SaveSystem.GetDirectoryInfo(Directory);
            foreach (DirectoryInfo directoryInfo in directoryList)
            {
                string entryPath = Path.Combine(Directory, directoryInfo.Name);
                SaveSystem.DeleteDirectory(entryPath);
            }
            OnEntriesChanged?.Invoke();        
        }

        private void ReloadEntries()
        {
            _entries.Clear();
            DirectoryInfo[] directoryList = SaveSystem.GetDirectoryInfo(Directory);
            foreach (DirectoryInfo directoryInfo in directoryList)
            {
                string entryPath = Path.Combine(Directory, directoryInfo.Name);
                _entries.Add(new SavedInventoryEntry(entryPath));
            }
            OnEntriesChanged?.Invoke();
        }

        public SavedInventory(string directory, string id)
        {
            Directory = directory;
            ID = id;
            ReloadEntries();
        }
    }
}