using System;
using Gallery.Util.Model;

namespace Gallery.Util
{
    public static class Extensions
    {
        public static int IndexOf<T>(this T[] array, Predicate<T> predicate)
        {
            for (var i = 0; i < array.Length; i++)
            {
                if (predicate(array[i]))
                {
                    return i;
                }
            }
            return -1;
        }

        public static int LastIndexOf<T>(this T[] array, Predicate<T> predicate)
        {
            for (var i = array.Length - 1; i >= 0; i--)
            {
                if (predicate(array[i]))
                {
                    return i;
                }
            }
            return -1;
        }

        public static bool All<T>(this T[] array, Predicate<T> predicate)
        {
            for (var i = 0; i < array.Length; i++)
            {
                if (!predicate(array[i]))
                {
                    return false;
                }
            }
            return true;
        }

        public static bool AnyFor<T>(this T[] array, int from, int to, Predicate<T> predicate)
        {
            for (var i = from; i <= to; i++)
            {
                if (predicate(array[i]))
                {
                    return true;
                }
            }
            return false;
        }

        public static DateTime ToLocalTime(this long time)
        {
            //return new DateTime(1970, 1, 1, 0, 0, 0).AddMilliseconds(time).ToLocalTime();
            return new DateTime(621355968000000000L + time * 10000000).ToLocalTime();
        }

        public static long ToTimestamp(this DateTime datetime)
        {
            var ticks = datetime.Ticks;
            return (ticks - 621355968000000000L) / 10000000;
        }

        public static bool SourceEquals(this GalleryItem a, GalleryItem b)
        {
            if (a == null || b == null)
            {
                return false;
            }
            return a.Id == b.Id && a.Source == b.Source;
        }
    }
}