using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text.RegularExpressions;
using UnityEngine;

namespace UnityTest
{
	[Serializable]
	public class PropertyResolver
	{
		public string[] ExcludedFieldNames { get; set; }
		public Type[] ExcludedTypes { get; set; }
		public Type[] AllowedTypes { get; set; }

		public PropertyResolver ()
		{
			ExcludedFieldNames = new string[] {};
			ExcludedTypes = new Type[] {};
			AllowedTypes = new Type[] {};
		}

		public IList<string> GetFieldsAndPropertiesUnderPath(GameObject go, string propertPath)
		{
			propertPath = propertPath.Trim ();
			if (!PropertyPathIsValid (propertPath))
			{
				throw new ArgumentException("Incorrent property path: " + propertPath);
			}

			var idx = propertPath.LastIndexOf('.');

			if (idx < 0)
			{
				var components = GetFieldsAndPropertiesFromGameObject(go, 2, null);
				return components;
			}

			var propertyToSearch = propertPath;
			Type type = null;
			try
			{
				type = GetPropertyTypeFromString(go, propertyToSearch);
				idx = propertPath.Length-1;

			}
			catch(ArgumentException)
			{
				try
				{
					propertyToSearch = propertPath.Substring(0, idx);
					type = GetPropertyTypeFromString(go, propertyToSearch);
				}
				catch (NullReferenceException)
				{
					var components = GetFieldsAndPropertiesFromGameObject(go, 2, null);
					return components.Where(s => s.StartsWith(propertPath.Substring(idx + 1))).ToArray();
				}
			}

			var resultList = new List<string>();
			var path = "";
			if(propertyToSearch.EndsWith("."))
				propertyToSearch = propertyToSearch.Substring(0, propertyToSearch.Length-1);
			foreach(var c in propertyToSearch)
			{
				if(c == '.')
					resultList.Add(path);
				path += c;
			}
			resultList.Add(path);
			foreach (var prop in type.GetProperties())
			{
				if (prop.Name.StartsWith(propertPath.Substring(idx + 1)))
					resultList.Add(propertyToSearch + "." + prop.Name);
			}
			foreach (var prop in type.GetFields())
			{
				if (prop.Name.StartsWith(propertPath.Substring(idx + 1)))
					resultList.Add(propertyToSearch + "." + prop.Name);
			}
			return resultList.ToArray();
		}

		private bool PropertyPathIsValid ( string propertPath )
		{
			if (propertPath.StartsWith ("."))
				return false;
			if (propertPath.IndexOf ("..") >= 0)
				return false;
			if (Regex.IsMatch (propertPath,
								@"\s"))
				return false;
			return true;
		}

		public IList<string> GetFieldsAndPropertiesFromGameObject ( GameObject gameObject, int depthOfSearch, string extendPath )
		{
			if(depthOfSearch<1) throw new ArgumentOutOfRangeException("depthOfSearch need to be greater than 0");

			var goVals = GetPropertiesAndFieldsFromType(typeof(GameObject),
														depthOfSearch - 1).Select(s => "gameObject." + s);

			var result = new List<string>();
			if (AllowedTypes == null || !AllowedTypes.Any() || AllowedTypes.Contains(typeof(GameObject)))
				result.Add("gameObject");
			result.AddRange (goVals);

			foreach (var componentType in GetAllComponents(gameObject))
			{
				if (AllowedTypes == null || !AllowedTypes.Any() || AllowedTypes.Contains(componentType))
					result.Add(componentType.Name);

				if (depthOfSearch > 1)
				{
					var vals = GetPropertiesAndFieldsFromType (componentType,
																depthOfSearch - 1 );
					var valsFullName = vals.Select (s => componentType.Name + "." + s);
					result.AddRange (valsFullName);
				}
			}

			if (!string.IsNullOrEmpty (extendPath))
			{
				var pathType = GetPropertyTypeFromString (gameObject,
														extendPath);
				var vals = GetPropertiesAndFieldsFromType (pathType,
																depthOfSearch - 1);
				var valsFullName = vals.Select (s => extendPath + "." + s);
				result.AddRange (valsFullName);
			}

			return result;
		}

		private string[] GetPropertiesAndFieldsFromType ( Type type, int level )
		{
			level--;

			var result = new List<string>();
			var fields = new List<MemberInfo>();
			fields.AddRange(type.GetFields());
			fields.AddRange(type.GetProperties());

			foreach (var member in fields)
			{
				var memberType = GetMemberFieldType(member);
				var memberTypeName = memberType.Name;

				if (AllowedTypes == null 
				    ||!AllowedTypes.Any()
					|| (AllowedTypes.Contains(memberType) && !ExcludedFieldNames.Contains(memberTypeName))
					)
				{
					result.Add(member.Name);
				}

				if (level > 0 && IsTypeOrNameNotExcluded(memberType, memberTypeName))
				{
					var vals = GetPropertiesAndFieldsFromType(memberType,
														level);
					var valsFullName = vals.Select(s => member.Name + "." + s);
					result.AddRange(valsFullName);
				}
			}
			return result.ToArray();
		}

		private Type GetMemberFieldType ( MemberInfo info )
		{
			if (info.MemberType == MemberTypes.Property)
				return (info as PropertyInfo).PropertyType;
			if (info.MemberType == MemberTypes.Field)
				return (info as FieldInfo).FieldType;
			throw new Exception("Only properties and fields are allowed");
		}

		private Type[] GetAllComponents ( GameObject gameObject )
		{
			var result = new List<Type>();
			var components = gameObject.GetComponents(typeof(Component));
			foreach (var component in components)
			{
				var componentType = component.GetType();
				if (IsTypeOrNameNotExcluded(componentType, null))
				{
					result.Add(componentType);
				}
			}
			return result.ToArray();
		}

		private bool IsTypeOrNameNotExcluded(Type memberType, string memberTypeName)
		{
			return !ExcludedTypes.Contains(memberType)
					&& !ExcludedFieldNames.Contains(memberTypeName);
		}

		#region Static helpers

		public static object GetPropertyValueFromString(GameObject gameObj, string propertyPath)
		{
			if (propertyPath == "")
				return gameObj;

			var propsQueue = new Queue<string>(propertyPath.Split('.').Where(s => !string.IsNullOrEmpty(s)));

			if (propsQueue == null) throw new ArgumentException("Incorrent property path");

			object result;
			if (char.IsLower(propsQueue.Peek()[0]))
			{
				result = gameObj;
			}
			else
			{
				result = gameObj.GetComponent(propsQueue.Dequeue());
			}
			Type type = result.GetType();

			while (propsQueue.Count != 0)
			{
				var nameToFind = propsQueue.Dequeue();

				var property = type.GetProperty(nameToFind);
				if (property != null)
				{
					result = property.GetGetMethod().Invoke(result,
															null);
				}
				else
				{
					var field = type.GetField(nameToFind);
					result = field.GetValue(result);
				}
				type = result.GetType();
			}
			return result;
		}

		private static Type GetPropertyTypeFromString(GameObject gameObj, string propertyPath)
		{
			if (propertyPath == "")
				return gameObj.GetType();

			var propsQueue = new Queue<string>(propertyPath.Split('.').Where(s => !string.IsNullOrEmpty(s)));

			if (propsQueue == null) throw new ArgumentException("Incorrent property path");

			Type result;
			if (char.IsLower(propsQueue.Peek()[0]))
			{
				result = gameObj.GetType();
			}
			else
			{
				var component = gameObj.GetComponent(propsQueue.Dequeue());

				if (component == null) throw new ArgumentException("Incorrent property path");

				result = component.GetType();
			}
			while (propsQueue.Count != 0)
			{
				var nameToFind = propsQueue.Dequeue();

				var property = result.GetProperty(nameToFind);
				if (property != null)
				{
					result = property.PropertyType;
				}
				else
				{
					var field = result.GetField(nameToFind);
					if (field == null) throw new ArgumentException("Incorrent property path");
					result = field.FieldType;
				}
			}
			return result;
		}

		#endregion
	}
}