using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Serialization;

namespace TransportGame.Model
{
    [XmlRoot("map")]
    public class Map
    {
        private float[,] grid;

        /// <summary>
        /// Gets or sets the water level
        /// </summary>
        [XmlElement("waterLevel")]
        public float WaterLevel { get; set; }

        /// <summary>
        /// Gets or sets the biome
        /// </summary>
        [XmlElement("biome")]
        public Biome Biome { get; set; }

        /// <summary>
        /// Gets the heights array in range [0,1]
        /// </summary>
        [XmlIgnore()]
        public float[,] Heights
        {
            get
            {
                return grid;
            }
        }

        /// <summary>
        /// Gets or sets the heights as raw bytes
        /// </summary>
        /// <remarks>
        /// Bytes are stored as such:
        /// 
        ///     Offset  Size    Content
        ///     ------------------------
        ///     0       4       Width
        ///     4       8       Height
        ///     8       var     32bit floating point values    
        ///     
        /// </remarks>
        [XmlElement("heights")]
        public byte[] HeightsRaw
        {
            get
            {
                List<byte> bytes = new List<byte>();

                bytes.AddRange(BitConverter.GetBytes(Width));
                bytes.AddRange(BitConverter.GetBytes(Height));

                for (int x = 0; x < Width; x++)
                    for (int y = 0; y < Height; y++)
                        bytes.AddRange(BitConverter.GetBytes(grid[x, y]));
                
                return bytes.ToArray();
            }
            set
            {
                int pos = 0;
                int w = BitConverter.ToInt32(value, pos); pos += sizeof(int);
                int h = BitConverter.ToInt32(value, pos); pos += sizeof(int);

                grid = new float[w, h];

                for (int x = 0; x < w; x++)
                    for (int y = 0; y < h; y++)
                    {
                        grid[x, y] = BitConverter.ToSingle(value, pos);
                        pos += sizeof(float);
                    }
            }
        }

        /// <summary>
        /// Initializes the map
        /// </summary>
        /// <remarks>
        /// Warning: heights array will be null.
        /// </remarks>
        public Map()
        {
        }

        /// <summary>
        /// Initializes the map
        /// </summary>
        /// <param name="width"></param>
        /// <param name="height"></param>
        public Map(int width, int height)
        {
            grid = new float[width, height];
        }

        /// <summary>
        /// Gets or sets the cell at specified position in range [0, Biome.Height]
        /// </summary>
        /// <param name="x">X</param>
        /// <param name="y">Y</param>
        /// <returns>Cell</returns>
        [XmlIgnore]
        public float this[int x, int y]
        {
            get
            {
                return grid[x, y] * Biome.Height;
            }
            set
            {
                grid[x, y] = value / Biome.Height;
            }
        }

        /// <summary>
        /// Gets width of map
        /// </summary>
        [XmlIgnore]
        public int Width { get { return grid.GetLength(0); } }

        /// <summary>
        /// Gets height of map
        /// </summary>
        [XmlIgnore]
        public int Height { get { return grid.GetLength(1); } }

        /// <summary>
        /// Returns true if specified cell is a water cell
        /// </summary>
        /// <param name="x">X</param>
        /// <param name="y">Y</param>
        /// <returns></returns>
        public bool IsWater(int x, int y)
        {
            return this[x, y] <= WaterLevel;
        }

        /// <summary>
        /// Returns true if given coordinates is inside the map
        /// </summary>
        /// <param name="x">X</param>
        /// <param name="y">Y</param>
        /// <returns>True if coordinates are inside the map</returns>
        public bool IsInside(int x, int y)
        {
            return x >= 0 && y >= 0 && x < Width && y < Height;
        }
    }
}