using InnovEnergy.Lib.Utils;

namespace InnovEnergy.Lib.Protocols.Modbus.Util;

public static class ArraySegmentExtensions
{
    public static ArraySegment<T> ToArraySegment<T>(this IEnumerable<T> enumerable) => enumerable switch
    {
        ArraySegment<T>  ars => ars,
        IReadOnlyList<T> rol => rol.ToArray(),
        _                    => enumerable.ToArray()
    };

    public static ArraySegment<T> Skip<T>(this ArraySegment<T> seg, Int32 count)
    {
        var skip = Math.Min(count, seg.Count);
        var take = seg.Count - skip;

        return new ArraySegment<T>(seg.Array!,seg.Offset+skip, take);
    }

    public static ArraySegment<T> Take<T>(this ArraySegment<T> seg, Int32 count)
    {
        var take = Math.Min(count, seg.Count);
        return new ArraySegment<T>(seg.Array!, seg.Offset, take);
    }

    public static ArraySegment<T> SkipLast<T>(this ArraySegment<T> seg, Int32 count)
    {
        var take = Math.Max(seg.Count - count, 0);
        return new ArraySegment<T>(seg.Array!, seg.Offset, take);
    }

    public static ArraySegment<T> SkipWhile<T>(this ArraySegment<T> seg, Func<T,Boolean> predicate)
    {
        var skip = Enumerable.TakeWhile(seg, predicate).Count();
        var take = seg.Count - skip;
        return new ArraySegment<T>(seg.Array!, seg.Offset, take);
    }

    public static ArraySegment<T> TakeWhile<T>(this ArraySegment<T> seg, Func<T,Boolean> predicate)
    {
        var take = Enumerable.TakeWhile(seg, predicate).Count();
        return new ArraySegment<T>(seg.Array!, seg.Offset, take);
    }


    public static ArraySegment<T> TakeLast<T>(this ArraySegment<T> seg, Int32 count)
    {
        var skip = Math.Max(seg.Count - count, 0);
        var take = seg.Count - skip;

        return new ArraySegment<T>(seg.Array!, seg.Offset+skip, take);
    }
}