ctac.MapService.GetMovableNeighbors C# (CSharp) Method

        public Dictionary<Vector2, Tile> GetMovableNeighbors(Tile center, int controllingPlayerId, Tile dest = null)
        {
            var ret = GetNeighbors(center.position);

            //filter tiles that are too high/low to move to & are passable
            ret = ret.Where(t => !t.Value.unpassable && isHeightPassable(t.Value, center)).ToDictionary(k => k.Key, v => v.Value);

            //filter out tiles with enemies on them that aren't the destination
            ret = ret.Where(t =>
                (dest != null && t.Key == dest.position) ||
                !pieces.Pieces.Any(m => m.tilePosition == t.Key && m.playerId != controllingPlayerId)
            ).ToDictionary(k => k.Key, v => v.Value);

            bool destinationOccupied = dest != null && pieces.Pieces.Any(p => p.tilePosition == dest.position);

            //make sure not to consider tiles that would be where the moving pieces lands when it attacks
            ret = ret.Where(t =>
                dest == null
                || dest.position == t.Key
                || !destinationOccupied
                || TileDistance(t.Key, dest.position) > 1
                || !pieces.Pieces.Any(p => p.tilePosition == t.Key)
            ).ToDictionary(k => k.Key, v => v.Value);

            return ret;
        }