using System;
using System.Text.Json;
using Server.Json;
using Server.Regions;

namespace Server.Engines.Spawners
{
    public class RegionSpawner : Spawner
    {
        private BaseRegion m_SpawnRegion;

        [Constructible(AccessLevel.Developer)]
        public RegionSpawner()
        {
        }

        [Constructible(AccessLevel.Developer)]
        public RegionSpawner(string spawnedName) : base(spawnedName)
        {
        }

        [Constructible(AccessLevel.Developer)]
        public RegionSpawner(
            int amount, int minDelay, int maxDelay, int team, int homeRange,
            params string[] spawnedNames
        ) : this(
            amount,
            TimeSpan.FromMinutes(minDelay),
            TimeSpan.FromMinutes(maxDelay),
            team,
            homeRange,
            spawnedNames
        )
        {
        }

        [Constructible(AccessLevel.Developer)]
        public RegionSpawner(
            int amount, TimeSpan minDelay, TimeSpan maxDelay, int team, int homeRange,
            params string[] spawnedNames
        ) : base(amount, minDelay, maxDelay, team, homeRange, spawnedNames)
        {
        }

        public RegionSpawner(DynamicJson json, JsonSerializerOptions options) : base(json, options)
        {
            json.GetProperty("map", options, out Map map);
            json.GetProperty("region", options, out string spawnRegion);

            m_SpawnRegion = Region.Find(spawnRegion, map) as BaseRegion;
            m_SpawnRegion?.InitRectangles();
        }

        public RegionSpawner(Serial serial) : base(serial)
        {
        }

        [CommandProperty(AccessLevel.Developer)]
        public BaseRegion SpawnRegion
        {
            get => m_SpawnRegion;
            set
            {
                m_SpawnRegion = value;
                m_SpawnRegion?.InitRectangles();

                InvalidateProperties();
            }
        }

        public override void GetSpawnerProperties(ObjectPropertyList list)
        {
            base.GetSpawnerProperties(list);

            if (Running && m_SpawnRegion != null)
            {
                list.Add(1076228, "region:\t{0}", m_SpawnRegion.Name); // ~1_DUMMY~ ~2_DUMMY~
            }
        }

        public override Point3D GetSpawnPosition(ISpawnable spawned, Map map)
        {
            if (m_SpawnRegion == null || map == null || map == Map.Internal || map != m_SpawnRegion.Map ||
                m_SpawnRegion.TotalWeight <= 0)
            {
                return Location;
            }

            bool waterMob, waterOnlyMob;

            if (spawned is Mobile mob)
            {
                waterMob = mob.CanSwim;
                waterOnlyMob = mob.CanSwim && mob.CantWalk;
            }
            else
            {
                waterMob = false;
                waterOnlyMob = false;
            }

            // Try 10 times to find a valid location.
            for (var i = 0; i < 10; i++)
            {
                var rand = Utility.Random(m_SpawnRegion.TotalWeight);

                var x = int.MinValue;
                var y = int.MinValue;

                for (var j = 0; j < m_SpawnRegion.RectangleWeights.Length; j++)
                {
                    var curWeight = m_SpawnRegion.RectangleWeights[j];

                    if (rand < curWeight)
                    {
                        var rect = m_SpawnRegion.Rectangles[j];

                        x = rect.Start.X + rand % rect.Width;
                        y = rect.Start.Y + rand / rect.Width;

                        break;
                    }

                    rand -= curWeight;
                }

                var mapZ = map.GetAverageZ(x, y);

                if (waterMob)
                {
                    if (IsValidWater(map, x, y, Z))
                    {
                        return new Point3D(x, y, Z);
                    }

                    if (IsValidWater(map, x, y, mapZ))
                    {
                        return new Point3D(x, y, mapZ);
                    }
                }

                if (!waterOnlyMob)
                {
                    if (map.CanSpawnMobile(x, y, Z))
                    {
                        return new Point3D(x, y, Z);
                    }

                    if (map.CanSpawnMobile(x, y, mapZ))
                    {
                        return new Point3D(x, y, mapZ);
                    }
                }
            }

            return HomeLocation;
        }

        public override void Deserialize(IGenericReader reader)
        {
            base.Deserialize(reader);

            var version = reader.ReadEncodedInt();

            m_SpawnRegion = Region.Find(reader.ReadString(), Map) as BaseRegion;
            m_SpawnRegion?.InitRectangles();
        }

        public override void Serialize(IGenericWriter writer)
        {
            base.Serialize(writer);

            writer.WriteEncodedInt(0); // version

            writer.Write(m_SpawnRegion?.Name);
        }
    }
}