using System;
using System.Collections.Generic;
using System.Threading;

namespace AspClassic.Scripting;

public sealed class ScopeVariableIgnoreCase : IScopeVariable, IWeakReferencable
{
	private readonly string _firstCasing;

	private readonly ScopeVariable _firstVariable;

	private WeakReference _weakref;

	private Dictionary<string, ScopeVariable> _overflow;

	public bool HasValue
	{
		get
		{
			if (_firstVariable.HasValue)
			{
				return true;
			}
			if (_overflow != null)
			{
				lock (_overflow)
				{
					foreach (KeyValuePair<string, ScopeVariable> item in _overflow)
					{
						if (item.Value.HasValue)
						{
							return true;
						}
					}
				}
			}
			return false;
		}
	}

	public WeakReference WeakReference
	{
		get
		{
			if (_weakref == null)
			{
				_weakref = new WeakReference(this);
			}
			return _weakref;
		}
	}

	internal ScopeVariableIgnoreCase(string casing)
	{
		_firstCasing = casing;
		_firstVariable = new ScopeVariable();
	}

	public bool TryGetValue(out dynamic value)
	{
		if (_firstVariable.TryGetValue(out var value2))
		{
			value = value2;
			return true;
		}
		if (_overflow != null)
		{
			lock (_overflow)
			{
				foreach (KeyValuePair<string, ScopeVariable> item in _overflow)
				{
					if (item.Value.TryGetValue(out value2))
					{
						value = value2;
						return true;
					}
				}
			}
		}
		value = null;
		return false;
	}

	public void SetValue(object value)
	{
		_firstVariable.SetValue(value);
	}

	public bool DeleteValue()
	{
		bool flag = _firstVariable.DeleteValue();
		if (_overflow != null)
		{
			lock (_overflow)
			{
				foreach (KeyValuePair<string, ScopeVariable> item in _overflow)
				{
					flag = item.Value.DeleteValue() || flag;
				}
				return flag;
			}
		}
		return flag;
	}

	internal ScopeVariable GetCaseSensitiveStorage(string name)
	{
		if (name == _firstCasing)
		{
			return _firstVariable;
		}
		return GetStorageSlow(name);
	}

	internal void AddNames(List<string> list)
	{
		if (_firstVariable.HasValue)
		{
			list.Add(_firstCasing);
		}
		if (_overflow == null)
		{
			return;
		}
		lock (_overflow)
		{
			foreach (KeyValuePair<string, ScopeVariable> item in _overflow)
			{
				if (item.Value.HasValue)
				{
					list.Add(item.Key);
				}
			}
		}
	}

	internal void AddItems(List<KeyValuePair<string, object>> list)
	{
		if (_firstVariable.TryGetValue(out var value))
		{
			list.Add(new KeyValuePair<string, object>(_firstCasing, value));
		}
		if (_overflow == null)
		{
			return;
		}
		lock (_overflow)
		{
			foreach (KeyValuePair<string, ScopeVariable> item in _overflow)
			{
				if (item.Value.TryGetValue(out value))
				{
					list.Add(new KeyValuePair<string, object>(item.Key, value));
				}
			}
		}
	}

	private ScopeVariable GetStorageSlow(string name)
	{
		if (_overflow == null)
		{
			Interlocked.CompareExchange(ref _overflow, new Dictionary<string, ScopeVariable>(), null);
		}
		lock (_overflow)
		{
			if (!_overflow.TryGetValue(name, out var value))
			{
				value = (_overflow[name] = new ScopeVariable());
			}
			return value;
		}
	}
}