using System;
using System.IO;
using System.Text;
using System.Windows.Forms;
using static DSPRE.RomInfo;

namespace DSPRE.ROMFiles {
   /* ---------------------- MATRIX DATA STRUCTURE (DPPtHGSS):-----------------------------

   0x0  //  byte:       Matrix width (a.k.a row length) (x)
   0x1  //  byte:       Matrix height (a.k.a number of rows per section) (y)
   0x2  //  byte:       Headers section boolean (0 = not present, 1 = present)
   0x3  //  byte:       Altitudes section flag (0 = not present, 1 = present)
   0x4  //  byte:       Length of matrix name string
   0x5  //  string:     Matrix name string (UTF-8 Encoded)
   --   //              [Header section if applicable: y blocks of length x]
   --   //              [Altitudes section if applicable: y blocks of length x]
   --   //              [Map files section: y blocks of length x]

   -------------------------------------------------------------------------------------- */

    /// <summary>
    /// Class to store map matrix data from Pokémon NDS games
    /// </summary>
    public class GameMatrix: RomFile {
        #region Fields (8)
        public static readonly string DefaultFilter = "Game Matrix File (*.mtx)|*.mtx";


        public bool hasHeadersSection { get; set; }
        public bool hasHeightsSection { get; set; }
        public string name { get; set; }
        public byte width { get; set; }
        public byte height { get; set; }
        public int? id { get; } = null;

        public ushort[,] headers;
        public byte[,] altitudes;
        public ushort[,] maps;

        public static readonly ushort EMPTY = 65535;
        #endregion Fields

        #region Constructors(1)
        public GameMatrix(Stream data) {
            using (BinaryReader reader = new BinaryReader(data)) {
                /* Read matrix size and sections included */
                width = reader.ReadByte();
                height = reader.ReadByte();

                if (reader.ReadBoolean()) {
                    hasHeadersSection = true;
                }

                if (reader.ReadBoolean()) {
                    hasHeightsSection = true;
                }

                /* Read matrix's name */
                byte nameLength = reader.ReadByte();
                name = Encoding.UTF8.GetString(reader.ReadBytes(nameLength));

                /* Initialize section arrays */
                headers = new ushort[height, width];
                altitudes = new byte[height, width];
                maps = new ushort[height, width];

                /* Read sections */
                if (hasHeadersSection) {
                    for (int i = 0; i < height; i++) {
                        for (int j = 0; j < width; j++) {
                            headers[i, j] = reader.ReadUInt16();
                        }
                    }
                }

                if (hasHeightsSection) {
                    for (int i = 0; i < height; i++) {
                        for (int j = 0; j < width; j++) {
                            altitudes[i, j] = reader.ReadByte();
                        }
                    }
                }

                for (int i = 0; i < height; i++) {
                    for (int j = 0; j < width; j++) {
                        maps[i, j] = reader.ReadUInt16();
                    }
                }
            }
        }
        public GameMatrix(int ID) : this (new FileStream(RomInfo.gameDirs[DirNames.matrices].unpackedDir + "\\" + ID.ToString("D4"), FileMode.Open)) {
            this.id = ID;
        }

        public GameMatrix(GameMatrix copy, int newID) { 
            this.id = newID;
            this.name = copy.name;
            this.width = copy.width;
            this.height = copy.height;

            this.hasHeadersSection = copy.hasHeadersSection;
            this.hasHeightsSection = copy.hasHeightsSection;

            this.maps = (ushort[,])copy.maps.Clone();
            this.altitudes = (byte[,])copy.altitudes.Clone();
            this.headers = (ushort[,])copy.headers.Clone();
        }

        public GameMatrix() {
            this.name = "newMatrix";
            this.hasHeadersSection = false;
            this.hasHeightsSection = false;

            this.width = 1;
            this.height = 1;
            this.maps = new ushort[1, 1] { { 0 } };
        }
        #endregion

        #region Methods (6)
        public void ResizeMatrix(int newHeight, int newWidth)
        {
            /*  Initialize new arrays   */
            ushort[,] newHeaders = new ushort[newHeight, newWidth];
            byte[,] newAltitudes = new byte[newHeight, newWidth];
            ushort[,] newMaps = new ushort[newHeight, newWidth];

            /* Copy existing headers and altitudes rows into new arrays. If new matrix is greater in any dimension, new entries will be zero */
            if (hasHeadersSection) {
                for (int i = 0; i < Math.Min(height, newHeight); i++) {
                    for (int j = 0; j < Math.Min(width, newWidth); j++) {
                        newHeaders[i, j] = headers[i, j];
                    }
                }
            }

            if (hasHeightsSection) {
                for (int i = 0; i < Math.Min(height, newHeight); i++) {
                    for (int j = 0; j < Math.Min(width, newWidth); j++) {
                        newAltitudes[i, j] = altitudes[i, j];
                    }
                }
            }

            /* Copy existing map rows into new array, and fill eventual new ones with Matrix.EMPTY (FF FF) */
            for (int i = 0; i < Math.Min(height, newHeight); i++) {
                for (int j = 0; j < Math.Min(width, newWidth); j++) {
                    newMaps[i, j] = maps[i, j];
                }
            }

            if (newHeight > height) {
                for (int i = height; i < newHeight; i++) {
                    for (int j = 0; j < newWidth; j++) {
                        newMaps[i, j] = GameMatrix.EMPTY;
                    }
                }
            }

            if (newWidth > width) {
                for (int j = width; j < newWidth; j++) {
                    for (int i = 0; i < newHeight; i++) {
                        newMaps[i, j] = GameMatrix.EMPTY;
                    }
                }
            }

            /* Substitute old arrays with new arrays */
            headers = newHeaders;
            altitudes = newAltitudes;
            maps = newMaps;

            /* Set new width and height */
            height = (byte)newHeight;
            width = (byte)newWidth;
        }

        public override string ToString() {
            return (this.id == null ? "" : id.ToString()) + ": " + this.name;
        }
        public override byte[] ToByteArray() {
            MemoryStream newData = new MemoryStream();
            using (BinaryWriter writer = new BinaryWriter(newData)) {
                writer.Write(width);
                writer.Write(height);
                writer.Write(hasHeadersSection);
                writer.Write(hasHeightsSection);
                writer.Write(name);

                if (hasHeadersSection) {
                    for (int i = 0; i < height; i++) {
                        for (int j = 0; j < width; j++) {
                            writer.Write(headers[i, j]);
                        }
                    }
                }

                if (hasHeightsSection) {
                    for (int i = 0; i < height; i++) {
                        for (int j = 0; j < width; j++) {
                            writer.Write(altitudes[i, j]);
                        }
                    }
                }

                for (int i = 0; i < height; i++) {
                    for (int j = 0; j < width; j++) {
                        writer.Write(maps[i, j]);
                    }
                }

            }
            return newData.ToArray();
        }
        public void SaveToFileDefaultDir(int IDtoReplace, bool showSuccessMessage = true) {
            SaveToFileDefaultDir(DirNames.matrices, IDtoReplace, showSuccessMessage);
        }
        public void SaveToFileExplorePath(string suggestedFileName, bool showSuccessMessage = true) {
            SaveToFileExplorePath("Gen IV Matrix File", "mtx", suggestedFileName, showSuccessMessage);
        }
        #endregion
    }
}