using System;
using System.Collections.Generic;
using AspClassic.Scripting.Utils;

namespace AspClassic.Scripting.Runtime;

public sealed class DlrConfiguration
{
	private bool _frozen;

	private readonly bool _debugMode;

	private readonly bool _privateBinding;

	private readonly IDictionary<string, object> _options;

	public static readonly StringComparer FileExtensionComparer = StringComparer.OrdinalIgnoreCase;

	public static readonly StringComparer LanguageNameComparer = StringComparer.OrdinalIgnoreCase;

	public static readonly StringComparer OptionNameComparer = StringComparer.Ordinal;

	private readonly Dictionary<string, LanguageConfiguration> _languageNames;

	private readonly Dictionary<string, LanguageConfiguration> _languageExtensions;

	private readonly Dictionary<AssemblyQualifiedTypeName, LanguageConfiguration> _languageConfigurations;

	private readonly Dictionary<Type, LanguageConfiguration> _loadedProviderTypes;

	public bool DebugMode => _debugMode;

	public bool PrivateBinding => _privateBinding;

	internal IDictionary<string, object> Options => _options;

	internal IDictionary<AssemblyQualifiedTypeName, LanguageConfiguration> Languages => _languageConfigurations;

	public DlrConfiguration(bool debugMode, bool privateBinding, IDictionary<string, object> options)
	{
		ContractUtils.RequiresNotNull(options, "options");
		_debugMode = debugMode;
		_privateBinding = privateBinding;
		_options = options;
		_languageNames = new Dictionary<string, LanguageConfiguration>(LanguageNameComparer);
		_languageExtensions = new Dictionary<string, LanguageConfiguration>(FileExtensionComparer);
		_languageConfigurations = new Dictionary<AssemblyQualifiedTypeName, LanguageConfiguration>();
		_loadedProviderTypes = new Dictionary<Type, LanguageConfiguration>();
	}

	public void AddLanguage(string languageTypeName, string displayName, IList<string> names, IList<string> fileExtensions, IDictionary<string, object> options)
	{
		AddLanguage(languageTypeName, displayName, names, fileExtensions, options, null);
	}

	internal void AddLanguage(string languageTypeName, string displayName, IList<string> names, IList<string> fileExtensions, IDictionary<string, object> options, string paramName)
	{
		ContractUtils.Requires(!_frozen, "Configuration cannot be modified once the runtime is initialized");
		ContractUtils.Requires(names.TrueForAll((string id) => !string.IsNullOrEmpty(id) && !_languageNames.ContainsKey(id)), paramName ?? "names", "Language name should not be null, empty or duplicated between languages");
		ContractUtils.Requires(fileExtensions.TrueForAll((string ext) => !string.IsNullOrEmpty(ext) && !_languageExtensions.ContainsKey(ext)), paramName ?? "fileExtensions", "File extension should not be null, empty or duplicated between languages");
		ContractUtils.RequiresNotNull(displayName, paramName ?? "displayName");
		if (string.IsNullOrEmpty(displayName))
		{
			ContractUtils.Requires(names.Count > 0, paramName ?? "displayName", "Must have a non-empty display name or a a non-empty list of language names");
			displayName = names[0];
		}
		AssemblyQualifiedTypeName assemblyQualifiedTypeName = AssemblyQualifiedTypeName.ParseArgument(languageTypeName, paramName ?? "languageTypeName");
		if (_languageConfigurations.ContainsKey(assemblyQualifiedTypeName))
		{
			throw new ArgumentException($"Duplicate language with type name '{assemblyQualifiedTypeName}'", "languageTypeName");
		}
		Dictionary<string, object> dictionary = new Dictionary<string, object>(_options);
		foreach (KeyValuePair<string, object> option in options)
		{
			dictionary[option.Key] = option.Value;
		}
		LanguageConfiguration value = new LanguageConfiguration(assemblyQualifiedTypeName, displayName, dictionary);
		_languageConfigurations.Add(assemblyQualifiedTypeName, value);
		foreach (string name in names)
		{
			_languageNames[name] = value;
		}
		foreach (string fileExtension in fileExtensions)
		{
			_languageExtensions[NormalizeExtension(fileExtension)] = value;
		}
	}

	internal static string NormalizeExtension(string extension)
	{
		if (extension[0] != '.')
		{
			return "." + extension;
		}
		return extension;
	}

	internal void Freeze()
	{
		_frozen = true;
	}

	internal bool TryLoadLanguage(ScriptDomainManager manager, AssemblyQualifiedTypeName providerName, out LanguageContext language)
	{
		if (_languageConfigurations.TryGetValue(providerName, out var value))
		{
			language = LoadLanguageContext(manager, value);
			return true;
		}
		language = null;
		return false;
	}

	internal bool TryLoadLanguage(ScriptDomainManager manager, string str, bool isExtension, out LanguageContext language)
	{
		Dictionary<string, LanguageConfiguration> dictionary = (isExtension ? _languageExtensions : _languageNames);
		if (dictionary.TryGetValue(str, out var value))
		{
			language = LoadLanguageContext(manager, value);
			return true;
		}
		language = null;
		return false;
	}

	private LanguageContext LoadLanguageContext(ScriptDomainManager manager, LanguageConfiguration config)
	{
		bool alreadyLoaded;
		LanguageContext languageContext = config.LoadLanguageContext(manager, out alreadyLoaded);
		if (!alreadyLoaded)
		{
			lock (_loadedProviderTypes)
			{
				Type type = languageContext.GetType();
				if (_loadedProviderTypes.TryGetValue(type, out var value))
				{
					throw new InvalidOperationException($"Language implemented by type '{config.ProviderName}' has already been loaded using name '{value.ProviderName}'");
				}
				_loadedProviderTypes.Add(type, config);
				return languageContext;
			}
		}
		return languageContext;
	}

	public string[] GetLanguageNames(LanguageContext context)
	{
		ContractUtils.RequiresNotNull(context, "context");
		List<string> list = new List<string>();
		foreach (KeyValuePair<string, LanguageConfiguration> languageName in _languageNames)
		{
			if (languageName.Value.LanguageContext == context)
			{
				list.Add(languageName.Key);
			}
		}
		return list.ToArray();
	}

	internal string[] GetLanguageNames(LanguageConfiguration config)
	{
		List<string> list = new List<string>();
		foreach (KeyValuePair<string, LanguageConfiguration> languageName in _languageNames)
		{
			if (languageName.Value == config)
			{
				list.Add(languageName.Key);
			}
		}
		return list.ToArray();
	}

	public string[] GetLanguageNames()
	{
		return ArrayUtils.MakeArray(_languageNames.Keys);
	}

	public string[] GetFileExtensions(LanguageContext context)
	{
		List<string> list = new List<string>();
		foreach (KeyValuePair<string, LanguageConfiguration> languageExtension in _languageExtensions)
		{
			if (languageExtension.Value.LanguageContext == context)
			{
				list.Add(languageExtension.Key);
			}
		}
		return list.ToArray();
	}

	internal string[] GetFileExtensions(LanguageConfiguration config)
	{
		List<string> list = new List<string>();
		foreach (KeyValuePair<string, LanguageConfiguration> languageExtension in _languageExtensions)
		{
			if (languageExtension.Value == config)
			{
				list.Add(languageExtension.Key);
			}
		}
		return list.ToArray();
	}

	public string[] GetFileExtensions()
	{
		return ArrayUtils.MakeArray(_languageExtensions.Keys);
	}

	internal LanguageConfiguration GetLanguageConfig(LanguageContext context)
	{
		foreach (LanguageConfiguration value in _languageConfigurations.Values)
		{
			if (value.LanguageContext == context)
			{
				return value;
			}
		}
		return null;
	}
}