using System;
using UnityEngine;

namespace Coolape
{
	public static class ArrayEx
	{
		public static int BinarySearch (this int[] array, int low, int high, int val)
		{
			while (low <= high) {
				int midpoint = (int)(((uint)high + (uint)low) >> 1);
				int v = array [midpoint];
				if (val == v) {
					return midpoint;
				} else if (val < v)
					high = midpoint - 1;
				else
					low = midpoint + 1;
			}
			return -1;
		}

		public static void Fill (this float[] array, float v)
		{
			for (int i = 0; i < array.Length; i++) {
				array [i] = v;
			}
		}

		public static void Fill (this double[] array, double v)
		{
			for (int i = 0; i < array.Length; i++) {
				array [i] = v;
			}
		}
	
		public static void Write2Matlab (this float[] array, string filename, string varname)
		{
			System.IO.StreamWriter file = new System.IO.StreamWriter (filename);
			file.WriteLine (varname + "=[");
			for (int c = 0; c < array.Length; c++) {
				file.WriteLine (array [c]); 
			}
			file.WriteLine ("];");
			file.Close ();
		}
	
		public static void CopyTo (this float[] array, float[] dest)
		{
			Array.Copy (array, dest, array.Length);
		}

		public static void CopyTo (this double[] array, double[] dest)
		{
			Array.Copy (array, dest, array.Length);
		}

		public static float Sum (this float[] array)
		{
			float sum = 0.0f;
			for (int i = 0; i < array.Length; i++) {
				sum += array [i];
			}
			return sum;
		}

		public static double Sum (this double[] array)
		{
			double sum = 0.0f;
			for (int i = 0; i < array.Length; i++) {
				sum += array [i];
			}
			return sum;
		}
	
		public static float Max (this float[] array)
		{
			float max = -float.MaxValue;
			for (int i = 0; i < array.Length; i++) {
				max = Mathf.Max (array [i], max);
			}
			return max;
		}

		public static float MaxDelta (this float[] x, float[] y)
		{
			float change = 0.0f;
			for (int i = 0; i < x.Length; i++) {
				change = Mathf.Max (Math.Abs (x [i] - y [i]), change);
			}
			return change;
		}

		public static double Max (this double[] array)
		{
			double max = -float.MaxValue;
			for (int i = 0; i < array.Length; i++) {
				max = Math.Max (array [i], max);
			}
			return max;
		}

		public static double MaxDelta (this double[] x, double[] y)
		{
			double change = 0.0f;
			for (int i = 0; i < x.Length; i++) {
				change = Math.Max (Math.Abs (x [i] - y [i]), change);
			}
			return change;
		}

		public static void MultiplyWith (this float[] x, float[] y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] *= y [i];
			}
		}

		public static void MultiplyWith (this float[] x, float y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] *= y;
			}
		}

		public static void DivideBy (this float[] x, float[] y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] /= y [i];
			}
		}

		public static float Dot (this float[] x, float[] y)
		{
			float dotProduct = 0.0f;
			for (int i = 0; i < x.Length; i++) {
				dotProduct += x [i] * y [i]; 
			}
			return dotProduct;
		}

		public static void MultiplyWith (this double[] x, double[] y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] *= y [i];
			}
		}

		public static void MultiplyWith (this double[] x, double y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] *= y;
			}
		}

		public static void DivideBy (this double[] x, double[] y)
		{
			for (int i = 0; i < x.Length; i++) {
				x [i] /= y [i];
			}
		}

		public static double Dot (this double[] x, double[] y)
		{
			double dotProduct = 0.0f;
			for (int i = 0; i < x.Length; i++) {
				dotProduct += x [i] * y [i]; 
			}
			return dotProduct;
		}

		public static string ToStringPretty (this float[] x)
		{
			string res = "[";
			for (int i = 0; i < x.Length; i++) {
				res += x [i] + ", ";
			}
			res += "]";
			return res;
		}
	}
}