using System;
using System.Collections.Generic;

namespace Learn.Models;

public class TreeNode(Item item)
{
    public class KeyValueInfo
    {
        public string Key { get; set; }
        public string Value { get; set; }
        public bool IsInherited { get; set; }
    }
    
    public TreeNode Parent => _parent;
    public IEnumerable<TreeNode> Children => _children;
    public Item Info => item;
    
    private TreeNode _parent;
    private readonly List<TreeNode> _children = new();

    public void AddNode(TreeNode node)
    {
        if (_children.Contains(node)) return;
        _children.Add(node);
        node._parent = this;
    }

    public IEnumerable<KeyValueInfo> GetKeyValueInfos()
    {
        var result = new List<KeyValueInfo>();
        var keys = new HashSet<string>();
        var curr = this;

        while (curr.Info != null)
        {
            foreach (var kv in curr.Info.Info)
            {
                if(!keys.Add(kv.Key)) continue;
                var keyValueInfo = new KeyValueInfo();
                
                if (curr != this)
                {
                    keyValueInfo.IsInherited = true;
                }
                
                keyValueInfo.Key = kv.Key;
                keyValueInfo.Value = kv.Value;
                result.Add(keyValueInfo);
            }
            curr = curr.Parent;
        }
        return result;
    }
}