using UnityEngine;
using UnityEditor;
using System;
using System.Text.RegularExpressions;
using System.IO;
using System.Collections.Generic;

namespace AmplifyShaderEditor
{
	[CustomEditor( typeof( AmplifyShaderFunction ) )]
	public class AmplifyShaderFunctionEditor : Editor
	{
		class FunctionDependency
		{
			public string AssetName;
			public string AssetPath;
			public FunctionDependency(string name, string path)
			{
				AssetName = name;
				AssetPath = path;
			}
		}

		AmplifyShaderFunction m_target;
		List<FunctionDependency> m_dependencies = new List<FunctionDependency>();

		void OnEnable()
		{
			m_target = ( target as AmplifyShaderFunction );
		}

		public override void OnInspectorGUI()
		{
			//base.OnInspectorGUI();
			//base.serializedObject.Update();
			if( GUILayout.Button( "Open in Shader Editor" ) )
			{
#if UNITY_2018_3_OR_NEWER
				ASEPackageManagerHelper.SetupLateShaderFunction( m_target );
#else
				AmplifyShaderEditorWindow.LoadShaderFunctionToASE( m_target, false );
#endif
			}
			//EditorGUILayout.Separator();
			//m_target.FunctionInfo = EditorGUILayout.TextArea( m_target.FunctionInfo );

			if( m_target.Description.Length > 0 )
			{
				EditorGUILayout.HelpBox( m_target.Description, MessageType.Info );
			}

			EditorGUILayout.Space();
			if( GUILayout.Button( "Search Direct Dependencies" ) )
			{
				m_dependencies.Clear();
				string guid = AssetDatabase.AssetPathToGUID( AssetDatabase.GetAssetPath( m_target ) );

				string[] allSFs = AssetDatabase.FindAssets( "t:AmplifyShaderFunction", null );
				foreach( string guid1 in allSFs )
				{
					string sfPath = AssetDatabase.GUIDToAssetPath( guid1 );
					bool found = SearchForGUID( guid, sfPath );
					if( found )
					{
						//string n = Regex.Replace( sfPath, @"(\.\w+|[\w\d\/]+\/)", "" );
						string n = Regex.Replace( sfPath, @"[\w\d\/]+\/", "" );
						m_dependencies.Add(new FunctionDependency( n, sfPath ) );
					}
				}

				string[] allSHs = AssetDatabase.FindAssets( "t:Shader", null );
				foreach( string guid1 in allSHs )
				{
					string shPath = AssetDatabase.GUIDToAssetPath( guid1 );
					bool found = SearchForGUID( guid, shPath );
					if( found )
					{
						string n = Regex.Replace( shPath, @"[\w\d\/]+\/", "" );
						m_dependencies.Add( new FunctionDependency( n, shPath ) );
					}
				}
			}
			EditorGUILayout.Space();
			for( int i = 0; i < m_dependencies.Count; i++ )
			{
				EditorGUILayout.BeginHorizontal();
				if( GUILayout.Button( m_dependencies[ i ].AssetName, "minibuttonleft" ) )
				{
					SelectAtPath( m_dependencies[ i ].AssetPath );
				}
				if( GUILayout.Button( "edit", "minibuttonright", GUILayout.Width(100) ) )
				{
					if( m_dependencies[ i ].AssetName.EndsWith( ".asset" ) )
					{
						var obj = AssetDatabase.LoadAssetAtPath<AmplifyShaderFunction>( m_dependencies[ i ].AssetPath );
						AmplifyShaderEditorWindow.LoadShaderFunctionToASE( obj, false );
					} 
					else
					{
						var obj = AssetDatabase.LoadAssetAtPath<Shader>( m_dependencies[ i ].AssetPath );
						AmplifyShaderEditorWindow.ConvertShaderToASE( obj );
					}
				}
				EditorGUILayout.EndHorizontal();
			}
		}

		public void SelectAtPath( string path )
		{
			var obj = AssetDatabase.LoadAssetAtPath<UnityEngine.Object>( path );
			EditorGUIUtility.PingObject( obj );
		}

		public static bool SearchForGUID( string guid, string pathName )
		{
			bool result = false;
			int count = 0;
			if( !string.IsNullOrEmpty( pathName ) && File.Exists( pathName ) )
			{
				StreamReader fileReader = null;
				try
				{
					fileReader = new StreamReader( pathName );

					string line;
					int index = -1;
					while( ( line = fileReader.ReadLine() ) != null )
					{
						index = line.IndexOf( guid );
						count++;

						if( index > -1 )
						{
							result = true;
							break;
						}
					}
				}
				catch( Exception e )
				{
					Debug.LogException( e );
				}
				finally
				{
					if( fileReader != null )
						fileReader.Close();
				}
			}
			return result;
		}
	}
}