using System;
using System.Diagnostics;
using Server.Items;
using Server.PathAlgorithms;
using Server.Spells;
using Server.Targeting;

namespace Server;

public sealed class MovementPath
{
    public MovementPath(Mobile m, Point3D goal)
    {
        var start = m.Location;
        var map = m.Map;

        Map = map;
        Start = start;
        Goal = goal;

        if (map == null || map == Map.Internal)
        {
            return;
        }

        if (Utility.InRange(start, goal, 1))
        {
            return;
        }

        try
        {
            var alg = OverrideAlgorithm ?? BitmapAStarAlgorithm.Instance;

            if (alg?.CheckCondition(m, map, start, goal) == true)
            {
                Directions = alg.Find(m, map, start, goal);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine("Warning: {0}: Pathing error from {1} to {2}", e.GetType().Name, start, goal);
        }
    }

    public Map Map { get; }

    public Point3D Start { get; }

    public Point3D Goal { get; }

    public Direction[] Directions { get; }

    public bool Success => Directions?.Length > 0;

    public static PathAlgorithm OverrideAlgorithm { get; set; }

    public static void Configure()
    {
        CommandSystem.Register("Path", AccessLevel.GameMaster, Path_OnCommand);
    }

    [Usage("Path")]
    [Description("Draws a path from your current location to a targeted location.")]
    public static void Path_OnCommand(CommandEventArgs e)
    {
        e.Mobile.BeginTarget(-1, true, TargetFlags.None, Path_OnTarget);
        e.Mobile.SendMessage("Target a location and a path will be drawn there.");
    }

    private static void Path(Mobile from, IPoint3D p, PathAlgorithm alg, string name, int zOffset)
    {
        OverrideAlgorithm = alg;

        var watch = new Stopwatch();
        watch.Start();
        var path = new MovementPath(from, new Point3D(p));
        watch.Stop();

        if (!path.Success)
        {
            from.SendMessage($"{name} path failed: {watch.ElapsedMilliseconds}ms");
        }
        else
        {
            from.SendMessage($"{name} path success: {watch.ElapsedMilliseconds}ms");

            var x = from.X;
            var y = from.Y;
            var z = from.Z;

            WayPoint waypoint = null;

            for (var i = 0; i < path.Directions.Length; ++i)
            {
                Movement.Movement.Offset(path.Directions[i], ref x, ref y);

                waypoint = new WayPoint(waypoint);
                waypoint.MoveToWorld(new Point3D(x, y, z + zOffset), from.Map);
            }
        }
    }

    public static void Path_OnTarget(Mobile from, object targeted)
    {
        if (targeted is not IPoint3D p)
        {
            return;
        }

        SpellHelper.GetSurfaceTop(ref p);

        Path(from, p, BitmapAStarAlgorithm.Instance, "Bitmap", 0);
        OverrideAlgorithm = null;
    }
}