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

namespace ProGrids
{
	public static class pg_Util
	{
		public static Color ColorWithString(string value)
		{
			string valid = "01234567890.,";
	        value = new string(value.Where(c => valid.Contains(c)).ToArray());
	        string[] rgba = value.Split(',');

	        // BRIGHT pink
	        if(rgba.Length < 4)
	        	return new Color(1f, 0f, 1f, 1f);

			return new Color(
				float.Parse(rgba[0]),
				float.Parse(rgba[1]),
				float.Parse(rgba[2]),
				float.Parse(rgba[3]));
		}

		private static Vector3 VectorToMask(Vector3 vec)
		{
			return new Vector3( Mathf.Abs(vec.x) > Mathf.Epsilon ? 1f : 0f,
								Mathf.Abs(vec.y) > Mathf.Epsilon ? 1f : 0f,
								Mathf.Abs(vec.z) > Mathf.Epsilon ? 1f : 0f );
		}

		private static Axis MaskToAxis(Vector3 vec)
		{
			Axis axis = Axis.None;
			if( Mathf.Abs(vec.x) > 0 ) axis |= Axis.X;
			if( Mathf.Abs(vec.y) > 0 ) axis |= Axis.Y;
			if( Mathf.Abs(vec.z) > 0 ) axis |= Axis.Z;
			return axis;
		}

		private static Axis BestAxis(Vector3 vec)
		{
			float x = Mathf.Abs(vec.x);
			float y = Mathf.Abs(vec.y);
			float z = Mathf.Abs(vec.z);

			return (x > y && x > z) ? Axis.X : ((y > x && y > z) ? Axis.Y : Axis.Z);
		}

		public static Axis CalcDragAxis(Vector3 movement, Camera cam)
		{
			Vector3 mask = VectorToMask(movement);

			if(mask.x + mask.y + mask.z == 2)
			{
				return MaskToAxis(Vector3.one - mask);
			}
			else
			{
				switch( MaskToAxis(mask) )
				{
					case Axis.X:
						if( Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.up)) < Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.forward)))
							return Axis.Z;
						else
							return Axis.Y;

					case Axis.Y:
						if( Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.right)) < Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.forward)))
							return Axis.Z;
						else
							return Axis.X;

					case Axis.Z:
						if( Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.right)) < Mathf.Abs(Vector3.Dot(cam.transform.forward, Vector3.up)))
							return Axis.Y;
						else
							return Axis.X;
					default:

						return Axis.None;
				}
			}
		}

		public static float ValueFromMask(Vector3 val, Vector3 mask)
		{
			if(Mathf.Abs(mask.x) > .0001f)
				return val.x;
			else if(Mathf.Abs(mask.y) > .0001f)
				return val.y;
			else
				return val.z;
		}

		public static Vector3 SnapValue(Vector3 val, float snapValue)
		{
			float _x = val.x, _y = val.y, _z = val.z;
			return new Vector3(
				Snap(_x, snapValue),
				Snap(_y, snapValue),
				Snap(_z, snapValue)
				);
		}

		/**
		 *	Fetch a type with name and optional assembly name.  `type` should include namespace.
		 */
		private static Type GetType(string type, string assembly = null)
		{
			Type t = Type.GetType(type);

			if(t == null)
			{
				IEnumerable<Assembly> assemblies = AppDomain.CurrentDomain.GetAssemblies();

				if(assembly != null)
					assemblies = assemblies.Where(x => x.FullName.Contains(assembly));

				foreach(Assembly ass in assemblies)
				{
					t = ass.GetType(type);

					if(t != null)
						return t;
				}
			}

			return t;
		}

		public static void SetUnityGridEnabled(bool isEnabled)
		{
			try
			{
				Type annotationUtility = GetType("UnityEditor.AnnotationUtility");
				PropertyInfo pi = annotationUtility.GetProperty("showGrid", BindingFlags.NonPublic | BindingFlags.Static);
				pi.SetValue(null, isEnabled, BindingFlags.NonPublic | BindingFlags.Static, null, null, null);
			}
			catch
			{}
		}

		public static bool GetUnityGridEnabled()
		{
			try
			{
				Type annotationUtility = GetType("UnityEditor.AnnotationUtility");
				PropertyInfo pi = annotationUtility.GetProperty("showGrid", BindingFlags.NonPublic | BindingFlags.Static);
				return (bool) pi.GetValue(null, null);
			}
			catch
			{}

			return false;
		}

		const float EPSILON = .0001f;
		public static Vector3 SnapValue(Vector3 val, Vector3 mask, float snapValue)
		{

			float _x = val.x, _y = val.y, _z = val.z;
			return new Vector3(
				( Mathf.Abs(mask.x) < EPSILON ? _x : Snap(_x, snapValue) ),
				( Mathf.Abs(mask.y) < EPSILON ? _y : Snap(_y, snapValue) ),
				( Mathf.Abs(mask.z) < EPSILON ? _z : Snap(_z, snapValue) )
				);
		}

		public static Vector3 SnapToCeil(Vector3 val, Vector3 mask, float snapValue)
		{
			float _x = val.x, _y = val.y, _z = val.z;
			return new Vector3(
				( Mathf.Abs(mask.x) < EPSILON ? _x : SnapToCeil(_x, snapValue) ),
				( Mathf.Abs(mask.y) < EPSILON ? _y : SnapToCeil(_y, snapValue) ),
				( Mathf.Abs(mask.z) < EPSILON ? _z : SnapToCeil(_z, snapValue) )
				);
		}

		public static Vector3 SnapToFloor(Vector3 val, float snapValue)
		{
			float _x = val.x, _y = val.y, _z = val.z;
			return new Vector3(
				SnapToFloor(_x, snapValue),
				SnapToFloor(_y, snapValue),
				SnapToFloor(_z, snapValue)
				);
		}

		public static Vector3 SnapToFloor(Vector3 val, Vector3 mask, float snapValue)
		{
			float _x = val.x, _y = val.y, _z = val.z;
			return new Vector3(
				( Mathf.Abs(mask.x) < EPSILON ? _x : SnapToFloor(_x, snapValue) ),
				( Mathf.Abs(mask.y) < EPSILON ? _y : SnapToFloor(_y, snapValue) ),
				( Mathf.Abs(mask.z) < EPSILON ? _z : SnapToFloor(_z, snapValue) )
				);
		}

		public static float Snap(float val, float round)
		{
			return round * Mathf.Round(val / round);
		}

		public static float SnapToFloor(float val, float snapValue)
		{
			return snapValue * Mathf.Floor(val / snapValue);
		}

		public static float SnapToCeil(float val, float snapValue)
		{
			return snapValue * Mathf.Ceil(val / snapValue);
		}

		public static Vector3 CeilFloor(Vector3 v)
		{
			v.x = v.x < 0 ? -1 : 1;
			v.y = v.y < 0 ? -1 : 1;
			v.z = v.z < 0 ? -1 : 1;

			return v;
		}

		abstract class SnapEnabledOverride
		{
			public abstract bool IsEnabled();
		}

		class SnapIsEnabledOverride : SnapEnabledOverride
		{
			bool m_SnapIsEnabled;

			public SnapIsEnabledOverride(bool snapIsEnabled)
			{
				m_SnapIsEnabled = snapIsEnabled;
			}

			public override bool IsEnabled() { return m_SnapIsEnabled; }
		}

		class ConditionalSnapOverride : SnapEnabledOverride
		{
			public System.Func<bool> m_IsEnabledDelegate;

			public ConditionalSnapOverride(System.Func<bool> d)
			{
				m_IsEnabledDelegate = d;
			}

			public override bool IsEnabled() { return m_IsEnabledDelegate(); }
		}

		private static Dictionary<Transform, SnapEnabledOverride> m_SnapOverrideCache = new Dictionary<Transform, SnapEnabledOverride>();
		private static Dictionary<Type, bool> m_NoSnapAttributeTypeCache = new Dictionary<Type, bool>();
		private static Dictionary<Type, MethodInfo> m_ConditionalSnapAttributeCache = new Dictionary<Type, MethodInfo>();

		public static void ClearSnapEnabledCache()
		{
			m_SnapOverrideCache.Clear();
		}

		public static bool SnapIsEnabled(Transform t)
		{
			SnapEnabledOverride so;

			if(m_SnapOverrideCache.TryGetValue(t, out so))
				return so.IsEnabled();

			object[] attribs = null;

			foreach(Component c in t.GetComponents<MonoBehaviour>())
			{
				Type type = c.GetType();

				bool hasNoSnapAttrib;

				if(m_NoSnapAttributeTypeCache.TryGetValue(type, out hasNoSnapAttrib))
				{
					if(hasNoSnapAttrib)
					{
						m_SnapOverrideCache.Add(t, new SnapIsEnabledOverride(!hasNoSnapAttrib));
						return true;
					}
				}
				else
				{
					attribs = type.GetCustomAttributes(true);
					hasNoSnapAttrib = attribs.Any(x => x != null && x.ToString().Contains("ProGridsNoSnap"));
					m_NoSnapAttributeTypeCache.Add(type, hasNoSnapAttrib);

					if(hasNoSnapAttrib)
					{
						m_SnapOverrideCache.Add(t, new SnapIsEnabledOverride(!hasNoSnapAttrib));
						return true;
					}
				}

				MethodInfo mi;

				if(m_ConditionalSnapAttributeCache.TryGetValue(type, out mi))
				{
					if(mi != null)
					{
						m_SnapOverrideCache.Add(t, new ConditionalSnapOverride(() => { return (bool) mi.Invoke(c, null); }));
						return (bool) mi.Invoke(c, null);
					}
				}
				else
				{
					if( attribs.Any(x => x != null && x.ToString().Contains("ProGridsConditionalSnap")) )
					{
						mi = type.GetMethod("IsSnapEnabled", BindingFlags.Instance | BindingFlags.FlattenHierarchy | BindingFlags.NonPublic | BindingFlags.Public);

						m_ConditionalSnapAttributeCache.Add(type, mi);

						if(mi != null)
						{
							m_SnapOverrideCache.Add(t, new ConditionalSnapOverride(() => { return (bool) mi.Invoke(c, null); }));
							return (bool) mi.Invoke(c, null);
						}
					}
					else
					{
						m_ConditionalSnapAttributeCache.Add(type, null);
					}
				}
			}

			m_SnapOverrideCache.Add(t, new SnapIsEnabledOverride(true));

			return true;
		}
	}

	public static class PGExtensions
	{
		public static bool Contains(this Transform[] t_arr, Transform t)
		{
			for(int i = 0; i < t_arr.Length; i++)
				if(t_arr[i] == t)
					return true;
			return false;
		}

		public static float Sum(this Vector3 v)
		{
			return v[0] + v[1] + v[2];
		}

		public static bool InFrustum(this Camera cam, Vector3 point)
		{
			Vector3 p = cam.WorldToViewportPoint(point);
			return  (p.x >= 0f && p.x <= 1f) &&
					(p.y >= 0f && p.y <= 1f) &&
					p.z >= 0f;
		}
	}

}
