using Cryville.Common.Unity.UI;
using Cryville.Crtr.Browsing.Actions;
using Cryville.Crtr.UI;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using TMPro;
using UnityEngine;
using UnityEngine.UI;

namespace Cryville.Crtr.Browsing.UI {
	internal class PathedResourceBrowser : ResourceBrowser {
		[SerializeField]
		Button[] m_writeTools;
		[SerializeField]
		TextMeshProUGUI m_pathText;
		[SerializeField]
		ScrollableItemGrid m_itemContainer;
		[SerializeField]
		DetailPanel m_detailPanel;
		[SerializeField]
		ActionBar m_actionBar;

		[SerializeField]
		Sprite m_readonlyIcon;
		public override Sprite Icon {
			get {
				return _manager.IsReadOnly ? m_readonlyIcon : base.Icon;
			}
		}

		IPathedResourceManager<IResourceMeta> _manager;
		IResourceAction _importAction;
		readonly IResourceAction[] _importActionArray = new IResourceAction[1];

		readonly HashSet<int> _selectedItems = new HashSet<int>();
		readonly Dictionary<int, BrowserItem> _items = new Dictionary<int, BrowserItem>();

		bool _destroyed;
		protected virtual void Start() {
			m_itemContainer.LoadItem = LoadItem;
		}
		void OnDestroy() {
			_destroyed = true;
			UnregisterManager();
		}
		void UnregisterManager() {
			if (_importAction != null) Master.Actions.Unregister(_importAction);
			_manager.ItemChanged -= OnItemChanged;
			_manager.DirectoryChanged -= OnDirectoryChanged;
		}

		void OnEnable() {
			if (_manager != null) _manager.Activate();
		}
		void OnDisable() {
			if (_manager != null) _manager.Deactivate();
		}

		public void Init(IPathedResourceManager<IResourceMeta> manager) {
			if (_manager != null) {
				OnDisable();
				UnregisterManager();
			}
			_manager = manager;
			_manager.ItemChanged += OnItemChanged;
			_manager.DirectoryChanged += OnDirectoryChanged;
			if (!_manager.IsReadOnly) {
				Master.Actions.Register(_importAction = _manager.GetImportAction());
				_importActionArray[0] = _importAction;
			}
			foreach (var tool in m_writeTools) tool.interactable = !_manager.IsReadOnly;

			OnEnable();
			OnItemChanged();
			OnDirectoryChanged();
		}

		bool _itemChanged;
		void OnItemChanged() {
			_itemChanged = true;
		}
		void OnDirectoryChanged() {
			if (_manager.CurrentDirectory.Count == 0) m_pathText.text = "(Home)";
			else m_pathText.text = string.Join(Path.DirectorySeparatorChar, _manager.CurrentDirectory);
		}
		void Update() {
			if (_itemChanged) {
				_itemChanged = false;
				_selectedItems.Clear();
				_items.Clear();
				m_itemContainer.ItemCount = _manager.Count;
				m_detailPanel.Clear();
				m_actionBar.Clear();
			}
		}

		private bool LoadItem(int id, GameObject obj) {
			var bi = obj.GetComponent<BrowserItem>();
			_items[id] = bi;
			try {
				var item = _manager[id];
				bi.Load(this, id, _manager.IsDirectory(id), item, _selectedItems.Contains(id));
			}
			catch (Exception) {
				bi.Load(this, id, _manager.IsDirectory(id), null, _selectedItems.Contains(id));
			}
			return true;
		}

		public override void OnItemClicked(int id) {
			if (_manager.IsDirectory(id)) {
				_manager.OpenDirectory(id);
			}
			else {
				foreach (var item in _selectedItems) _items[item].OnDeselect();
				_selectedItems.Clear();
				_items[id].OnSelect();
				_selectedItems.Add(id);
				try {
					var res = _manager[id];
					m_detailPanel.Load(res);
					if (_selectedItems.Count == 1) {
						LoadActions(_manager.GetItemUri(id), res);
					}
				}
				catch (Exception ex) {
					Popup.CreateException(ex);
				}
			}
		}
		internal override void OnActionsChanged() {
			if (_destroyed) return;
			if (_selectedItems.Count == 1) {
				int id = _selectedItems.Single();
				LoadActions(_manager.GetItemUri(id), _manager[id]);
			}
		}
		void LoadActions(Uri uri, IResourceMeta res) {
			m_actionBar.Load(this, Master.Actions.GetActions(uri, res).Except(_importActionArray));
		}

		public void OnPathClicked(int index) {
			_manager.ReturnToDirectory(index);
		}
		public void OnHomeClicked() {
			_manager.ChangeDirectory(Enumerable.Empty<string>());
		}
		public void OnParentClicked() {
			var depth = _manager.CurrentDirectory.Count;
			if (depth <= 0) return;
			_manager.ReturnToDirectory(_manager.CurrentDirectory.Count - 2);
		}
		public void OnSearch(string value) {
			_manager.ApplyFilter(value);
		}

		public void OnDeleteClicked() {
			if (_selectedItems.Count == 0) {
				Popup.Create("No item is selected.");
				return;
			}
			Dialog.Show(DeleteSelectedItems, "Are you sure to delete the selected item(s)?", "Yes", "No");
		}
		void DeleteSelectedItems(int result) {
			if (result != 0) return;
			foreach (var item in _selectedItems.OrderByDescending(i => i)) _manager.RemoveAt(item);
		}

		public override void InvokeAction(IResourceAction action) {
			if (_selectedItems.Count == 0) {
				Popup.Create("No item is selected.");
				return;
			}
			if (_selectedItems.Count > 1) {
				Popup.Create("Cannot run this action with multiple items.");
				return;
			}
			foreach (var i in _selectedItems) {
				try {
					action.Invoke(_manager.GetItemUri(i), _manager[i]);
				}
				catch (Exception ex) {
					Dialog.Show(null, ex.Message);
					Game.MainLogger.Log(4, "Config", "An error occurred while running the action: {0}", ex);
				}
			}
		}
	}
}