// XAML Map Control - https://github.com/ClemensFischer/XAML-Map-Control
// Copyright © Clemens Fischer
// Licensed under the Microsoft Public License (Ms-PL)

using System;
using System.Globalization;

namespace MapControl
{
    /// <summary>
    /// A geographic bounding box with south and north latitude and west and east longitude values in degrees.
    /// </summary>
#if UWP || WINUI
    [Windows.Foundation.Metadata.CreateFromString(MethodName = "Parse")]
#else
    [System.ComponentModel.TypeConverter(typeof(BoundingBoxConverter))]
#endif
    public class BoundingBox
    {
        protected BoundingBox()
        {
        }

        public BoundingBox(double latitude1, double longitude1, double latitude2, double longitude2)
        {
            South = Math.Min(Math.Max(Math.Min(latitude1, latitude2), -90d), 90d);
            North = Math.Min(Math.Max(Math.Max(latitude1, latitude2), -90d), 90d);
            West = Math.Min(longitude1, longitude2);
            East = Math.Max(longitude1, longitude2);
        }

        public BoundingBox(Location location1, Location location2)
            : this(location1.Latitude, location1.Longitude, location2.Latitude, location2.Longitude)
        {
        }

        public double South { get; }
        public double North { get; }
        public double West { get; }
        public double East { get; }

        public virtual double Width => East - West;
        public virtual double Height => North - South;

        public virtual Location Center => new Location((South + North) / 2d, (West + East) / 2d);

        /// <summary>
        /// Creates a BoundingBox instance from a string containing a comma-separated sequence of four or five floating point numbers.
        /// </summary>
        public static BoundingBox Parse(string boundingBox)
        {
            string[] values = null;

            if (!string.IsNullOrEmpty(boundingBox))
            {
                values = boundingBox.Split(new char[] { ',' });
            }

            if (values == null || values.Length != 4 && values.Length != 5)
            {
                throw new FormatException($"{nameof(BoundingBox)} string must contain a comma-separated sequence of four or five floating point numbers.");
            }

            var rotation = values.Length == 5
                ? double.Parse(values[4], NumberStyles.Float, CultureInfo.InvariantCulture)
                : 0d;

            // always return a LatLonBox, i.e. a BoundingBox with optional rotation, as used by GeoImage and GroundOverlay
            //
            return new LatLonBox(
                double.Parse(values[0], NumberStyles.Float, CultureInfo.InvariantCulture),
                double.Parse(values[1], NumberStyles.Float, CultureInfo.InvariantCulture),
                double.Parse(values[2], NumberStyles.Float, CultureInfo.InvariantCulture),
                double.Parse(values[3], NumberStyles.Float, CultureInfo.InvariantCulture),
                rotation);
        }
    }
}