using System.Collections.Generic;
using System.Linq;
using Godot;
using Learn.Models;

public partial class ItemInfoPanel : Tree
{
	private IEnumerable<TreeNode> _nodes;
	private ItemGroup _itemGroup;

	#region Columns Definitions
	private const int EmptyColumn = 0;
	private const int KeyColumn = 1;
	private const int ValueColumn = 2;
	#endregion
	
	public override void _Ready()
	{
		Columns = 3;
		SetColumnTitlesVisible(true);
		
		SetColumnCustomMinimumWidth(EmptyColumn, 30);
		SetColumnExpand(EmptyColumn, false);
		
		SetColumnTitle(KeyColumn, "键");
		SetColumnCustomMinimumWidth(KeyColumn, 100);
		SetColumnExpand(KeyColumn, false);
		
		SetColumnTitle(ValueColumn, "值");
		SetColumnExpand(ValueColumn, true);

		ItemEdited += OnItemEdited;
	}

	private readonly Godot.Collections.Dictionary<TreeItem, string> _nodeKeys = new ();
	
	private void OnItemEdited()
	{
		var node = GetEdited();
		var prevKey = _nodeKeys[node];
		var currentKey = node.GetText(KeyColumn);
		var value = node.GetText(ValueColumn);
		if (prevKey != currentKey)
		{
			_itemGroup.Remove(prevKey);
		}
		_itemGroup.SetValue(currentKey, value);
	}

	public void SetSelectedNodes(IEnumerable<TreeNode> nodes)
	{
		if (nodes == null)
		{
			_nodes = null;
			_itemGroup = null;
		}
		else
		{
			_nodes = nodes;
			_itemGroup = new ItemGroup(_nodes.Select(node => node.Info).ToList());
		}
		OnCurrentItemChanged();
	}
	
	private void OnCurrentItemChanged()
	{
		Clear();
		_nodeKeys.Clear();
		if (_itemGroup == null) return;
		var root = CreateItem();
		foreach (var key in _itemGroup.GetKeys())
		{
			if(!_itemGroup.TryGetValue(key, out var value, out var isSame)) continue;
			var node = CreateItem(root);
			
			node.SetText(KeyColumn, key);
			node.SetText(ValueColumn, isSame ? value : "-");
			node.SetEditable(KeyColumn, true);
			node.SetEditable(ValueColumn, true);
			_nodeKeys.Add(node, key);
		}
	}

	private void AddKeyValue()
	{
		if(_itemGroup == null) return;
		var newFieldName = "newField";
		int index = 0;
		while (!_itemGroup.TryAdd(newFieldName + (index == 0 ? "" : index.ToString()), ""))
		{
			index += 1;
		}
		OnCurrentItemChanged();
	}

	private void RemoveKeyValue()
	{
		if(_itemGroup == null) return;

		var node = GetSelected();
		var root = GetRoot();
		while (node != null)
		{
			_itemGroup.Remove(_nodeKeys[node]);
			_nodeKeys.Remove(node);
			var next = GetNextSelected(node);
			root.RemoveChild(node);
			node = next;
		}
	}
}