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

namespace OpenNest.Engine.Strategies
{
    public class LinearFillStrategy : IFillStrategy
    {
        public string Name => "Linear";
        public NestPhase Phase => NestPhase.Linear;
        public int Order => 400;

        public List<Part> Fill(FillContext context)
        {
            var angles = context.SharedState.TryGetValue("AngleCandidates", out var cached)
                ? (List<double>)cached
                : new List<double> { 0, Angle.HalfPI };

            var workArea = context.WorkArea;
            var comparer = context.Policy?.Comparer ?? new DefaultFillComparer();
            var preferred = context.Policy?.PreferredDirection;

            return FillHelpers.BestOverAngles(
                context,
                angles,
                angle =>
                {
                    var engine = new FillLinear(workArea, context.Plate.PartSpacing)
                    {
                        Label = "Linear",
                    };
                    var result = FillHelpers.FillWithDirectionPreference(
                        dir => engine.Fill(context.Item.Drawing, angle, dir),
                        preferred,
                        comparer,
                        workArea
                    );

                    if (result != null && result.Count > 0)
                    {
                        context.AngleResults.Add(
                            new AngleResult
                            {
                                AngleDeg = Angle.ToDegrees(angle),
                                Direction = preferred ?? NestDirection.Horizontal,
                                PartCount = result.Count,
                            }
                        );
                    }

                    return result;
                },
                "Linear"
            );
        }
    }
}