using System;
using OpenNest.CNC;

namespace OpenNest;

/// <summary>Explicit-ID input mapping and exact supported-geometry reconstruction. Never retains caller objects.</summary>
public static class DrawingJobMapper
{
    public static NestJobPart FromDrawing(string partId, Drawing drawing, int quantity)
    {
        ArgumentNullException.ThrowIfNull(drawing);
        var constraints = drawing.Constraints;
        return new NestJobPart(partId, PartGeometrySnapshot.FromProgram(drawing.Program), quantity, drawing.Priority,
            constraints == null ? RotationPolicy.Automatic :
                RotationPolicy.FromLegacy(constraints.StepAngle, constraints.StartAngle, constraints.EndAngle));
    }

    public static NestJobPart FromItem(string partId, NestItem item)
    {
        ArgumentNullException.ThrowIfNull(item);
        ArgumentNullException.ThrowIfNull(item.Drawing);
        return new NestJobPart(partId, PartGeometrySnapshot.FromProgram(item.Drawing.Program), item.Quantity,
            item.Priority, RotationPolicy.FromLegacy(item.StepAngle, item.RotationStart, item.RotationEnd));
    }

    /// <summary>Available stock is explicit; the legacy plate repeat count is not inventory.</summary>
    public static NestPlateStock FromPlate(string stockId, Plate plate, int? quantity)
    {
        ArgumentNullException.ThrowIfNull(plate);
        return new NestPlateStock(stockId, plate.Size, quantity, plate.PartSpacing, plate.EdgeSpacing, plate.Quadrant);
    }

    public static Program ToProgram(PartGeometrySnapshot geometry)
    {
        ArgumentNullException.ThrowIfNull(geometry);
        var program = new Program(geometry.Mode);
        foreach (var motion in geometry.Motions)
        {
            var code = motion.Type switch
            {
                CodeType.RapidMove => (Motion)new RapidMove(motion.X, motion.Y),
                CodeType.LinearMove => new LinearMove(motion.X, motion.Y) { Layer = motion.Layer },
                CodeType.ArcMove => new ArcMove(motion.X, motion.Y, motion.CenterX, motion.CenterY, motion.Rotation)
                    { Layer = motion.Layer },
                _ => throw new NotSupportedException("Unsupported snapshot motion.")
            };
            code.Suppressed = motion.Suppressed;
            program.Codes.Add(code);
        }
        return program;
    }

    internal static Drawing CreateDrawing(NestJobPart part)
    {
        var drawing = new Drawing(part.Id, ToProgram(part.Geometry)) { Priority = part.Priority };
        drawing.Quantity.Required = part.Quantity;
        drawing.Constraints = new NestConstraints
        {
            StepAngle = LegacyStep(part.Rotation),
            StartAngle = part.Rotation.Start,
            EndAngle = part.Rotation.End
        };
        return drawing;
    }

    // A fixed angle needs a nonzero legacy step so it is not misread as automatic.
    internal static double LegacyStep(RotationPolicy policy) => policy.Kind == RotationPolicyKind.Fixed
        ? OpenNest.Math.Angle.TwoPI : policy.Step;

    internal static Plate CreatePlate(NestPlateStock stock) => new(stock.Size)
    {
        Quantity = 1,
        PartSpacing = stock.PartSpacing,
        EdgeSpacing = stock.EdgeSpacing,
        Quadrant = stock.Quadrant
    };
}