using OpenNest.Engine.Fill;
using OpenNest.Math;
using System.Collections.Generic;

namespace OpenNest.Engine.Strategies
{
    public class ExtentsFillStrategy : IFillStrategy
    {
        public string Name => "Extents";
        public NestPhase Phase => NestPhase.Extents;
        public int Order => 300;

        public List<Part> Fill(FillContext context)
        {
            var filler = new FillExtents(context.WorkArea, context.Plate.PartSpacing);

            var bestRotation = context.SharedState.TryGetValue("BestRotation", out var rot)
                ? (double)rot
                : RotationAnalysis.FindBestRotation(context.Item);

            var angles = new[] { bestRotation, bestRotation + Angle.HalfPI };

            List<Part> best = null;
            var comparer = context.Policy?.Comparer ?? new DefaultFillComparer();

            foreach (var angle in angles)
            {
                context.Token.ThrowIfCancellationRequested();
                var result = filler.Fill(context.Item.Drawing, angle,
                    context.PlateNumber, context.Token, context.Progress);
                if (result != null && result.Count > 0)
                {
                    if (best == null || comparer.IsBetter(result, best, context.WorkArea))
                        best = result;
                }
            }

            return best ?? new List<Part>();
        }
    }
}