Gigas002/GTiff2Tiles

using GTiff2Tiles.Core.Enums;
using GTiff2Tiles.Core.Images;
using GTiff2Tiles.Core.Localization;
using GTiff2Tiles.Core.Tiles;

// ReSharper disable MemberCanBePrivate.Global
// ReSharper disable UnusedMember.Global
// ReSharper disable MemberCanBeProtected.Global

namespace GTiff2Tiles.Core.Coordinates;

/// <summary>
/// Class for geographical coordinates
/// </summary>
public class GeoCoordinate : Coordinate
{
    #region Constructors

    /// <inheritdoc />
    protected GeoCoordinate(double x, double y) : base(x, y) { }

    #endregion

    #region Methods

    /// <inheritdoc />
    /// <exception cref="ArgumentOutOfRangeException"/>
    public override Number ToNumber(int z, Size tileSize, bool tmsCompatible)
    {
        #region Preconditions checks

        if (z < 0) throw new ArgumentOutOfRangeException(nameof(z));

        #endregion

        PixelCoordinate pixelCoordinate = ToPixelCoordinate(z, tileSize);

        return pixelCoordinate.ToNumber(z, tileSize, tmsCompatible);
    }

    /// <summary>
    /// Gets <see cref="Number"/>s for specified <see cref="GeoCoordinate"/>s
    /// </summary>
    /// <param name="minCoordinate">Minimal <see cref="GeoCoordinate"/></param>
    /// <param name="maxCoordinate">Maximal <see cref="GeoCoordinate"/></param>
    /// <param name="z">Zoom</param>
    /// <param name="tileSize"><see cref="ITile"/>'s size
    /// <remarks><para/>Must be square</remarks></param>
    /// <param name="tmsCompatible">Is <see cref="ITile"/> tms compatible?</param>
    /// <returns><see cref="ValueTuple{T1, T2}"/> of <see cref="Number"/>s</returns>
    public static (Number minNumber, Number maxNumber) GetNumbers(GeoCoordinate minCoordinate,
                                                                  GeoCoordinate maxCoordinate, int z, Size tileSize, bool tmsCompatible)
    {
        #region Preconditions checks

        if (minCoordinate == null) throw new ArgumentNullException(nameof(minCoordinate));
        if (maxCoordinate == null) throw new ArgumentNullException(nameof(maxCoordinate));
        // zoom and size are checked on lower levels

        #endregion

        Number minCoordNumber = minCoordinate.ToNumber(z, tileSize, tmsCompatible);
        Number maxCoordNumber = maxCoordinate.ToNumber(z, tileSize, tmsCompatible);

        Number minNumber = new(Math.Min(minCoordNumber.X, maxCoordNumber.X),
                               Math.Min(minCoordNumber.Y, maxCoordNumber.Y),
                               minCoordNumber.Z);
        Number maxNumber = new(Math.Max(minCoordNumber.X, maxCoordNumber.X),
                               Math.Max(minCoordNumber.Y, maxCoordNumber.Y),
                               maxCoordNumber.Z);

        return (minNumber, maxNumber);
    }

    /// <summary>
    /// Convert current <see cref="GeoCoordinate"/> to <see cref="PixelCoordinate"/>
    /// </summary>
    /// <param name="z">Zoom
    /// <remarks><para/>Must be >= 0</remarks></param>
    /// <param name="tileSize"><see cref="ITile"/>'s size
    /// <remarks><para/>Must be square</remarks></param>
    /// <returns>Converted <see cref="PixelCoordinate"/></returns>
    public virtual PixelCoordinate ToPixelCoordinate(int z, Size tileSize) => null;

    /// <summary>
    /// Resolution for given zoom level (measured at Equator)
    /// </summary>
    /// <param name="z">Zoom
    /// <remarks><para/>Must be >= 0</remarks></param>
    /// <param name="tileSize"><see cref="ITile"/>'s size
    /// <remarks><para/>Must be square</remarks></param>
    /// <param name="coordinateSystem">Coordinate system</param>
    /// <returns>Resolution value or -1.0 if something goes wrong</returns>
    /// <exception cref="NotSupportedException"/>
    public static double Resolution(int z, Size tileSize, CoordinateSystem coordinateSystem) =>
        coordinateSystem switch
        {
            CoordinateSystem.Epsg4326 => GeodeticCoordinate.Resolution(z, tileSize),
            CoordinateSystem.Epsg3857 => MercatorCoordinate.Resolution(z, tileSize),
            _ => throw new NotSupportedException(string.Format(Strings.Culture, Strings.NotSupported, coordinateSystem))
        };

    /// <summary>
    /// Calculate zoom from known pixel size
    /// </summary>
    /// <param name="pixelSize">Pixel size</param>
    /// <param name="tileSize"><see cref="ITile"/>'s size
    /// <remarks><para/>Must be square</remarks></param>
    /// <param name="coordinateSystem">Coordinate system</param>
    /// <param name="minZ">Minimal zoom
    /// <para/>Must be >= 0 and lesser or equal, than <paramref name="maxZ"/>
    /// <para/>0 by default</param>
    /// <param name="maxZ">Maximal zoom
    /// <para/>Must be >= 0 and bigger or equal, than <paramref name="minZ"/>
    /// <para/>32 by default</param>
    /// <returns>Approximate zoom value</returns>
    public static int ZoomForPixelSize(int pixelSize, Size tileSize, CoordinateSystem coordinateSystem,
                                       int minZ = 0, int maxZ = 32)
    {
        #region Preconditions checks

        if (pixelSize <= 0) throw new ArgumentOutOfRangeException(nameof(pixelSize));
        if (minZ < 0) throw new ArgumentOutOfRangeException(nameof(minZ));
        if (maxZ < minZ) throw new ArgumentOutOfRangeException(nameof(maxZ));

        #endregion

        IEnumerable<int> range = Enumerable.Range(minZ, maxZ + 1);

        foreach (int i in range.Where(i => pixelSize > Resolution(i, tileSize, coordinateSystem)))
            return Math.Max(0, i - 1);

        return maxZ - 1;
    }

    #endregion
}