using System;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Controls;
using LiveCharts;
using LiveCharts.Defaults;
using LiveCharts.Wpf;
using Wpf.Annotations;

namespace Wpf.CartesianChart.StackedArea
{
    /// <summary>
    /// Interaction logic for StackedLine.xaml
    /// </summary>
    public partial class StackedAreaExample : INotifyPropertyChanged
    {
        private Func<double, string> _yFormatter;

        public StackedAreaExample()
        {
            InitializeComponent();

            SeriesCollection = new SeriesCollection
            {
                new StackedAreaSeries
                {
                    Title = "Africa",
                    Values = new ChartValues<DateTimePoint>
                    {
                        new DateTimePoint(new DateTime(1950, 1, 1), .228),
                        new DateTimePoint(new DateTime(1960, 1, 1), .285),
                        new DateTimePoint(new DateTime(1970, 1, 1), .366),
                        new DateTimePoint(new DateTime(1980, 1, 1), .478),
                        new DateTimePoint(new DateTime(1990, 1, 1), .629),
                        new DateTimePoint(new DateTime(2000, 1, 1), .808),
                        new DateTimePoint(new DateTime(2010, 1, 1), 1.031),
                        new DateTimePoint(new DateTime(2013, 1, 1), 1.110)
                    },
                    LineSmoothness = 0
                },
                new StackedAreaSeries
                {
                    Title = "N & S America",
                    Values = new ChartValues<DateTimePoint>
                    {
                        new DateTimePoint(new DateTime(1950, 1, 1), .339),
                        new DateTimePoint(new DateTime(1960, 1, 1), .424),
                        new DateTimePoint(new DateTime(1970, 1, 1), .519),
                        new DateTimePoint(new DateTime(1980, 1, 1), .618),
                        new DateTimePoint(new DateTime(1990, 1, 1), .727),
                        new DateTimePoint(new DateTime(2000, 1, 1), .841),
                        new DateTimePoint(new DateTime(2010, 1, 1), .942),
                        new DateTimePoint(new DateTime(2013, 1, 1), .972)
                    },
                    LineSmoothness = 0
                },
                new StackedAreaSeries
                {
                    Title = "Asia",
                    Values = new ChartValues<DateTimePoint>
                    {
                        new DateTimePoint(new DateTime(1950, 1, 1), 1.395),
                        new DateTimePoint(new DateTime(1960, 1, 1), 1.694),
                        new DateTimePoint(new DateTime(1970, 1, 1), 2.128),
                        new DateTimePoint(new DateTime(1980, 1, 1), 2.634),
                        new DateTimePoint(new DateTime(1990, 1, 1), 3.213),
                        new DateTimePoint(new DateTime(2000, 1, 1), 3.717),
                        new DateTimePoint(new DateTime(2010, 1, 1), 4.165),
                        new DateTimePoint(new DateTime(2013, 1, 1), 4.298)
                    },
                    LineSmoothness = 0
                },
                new StackedAreaSeries
                {
                    Title = "Europe",
                    Values = new ChartValues<DateTimePoint>
                    {
                        new DateTimePoint(new DateTime(1950, 1, 1), .549),
                        new DateTimePoint(new DateTime(1960, 1, 1), .605),
                        new DateTimePoint(new DateTime(1970, 1, 1), .657),
                        new DateTimePoint(new DateTime(1980, 1, 1), .694),
                        new DateTimePoint(new DateTime(1990, 1, 1), .723),
                        new DateTimePoint(new DateTime(2000, 1, 1), .729),
                        new DateTimePoint(new DateTime(2010, 1, 1), .740),
                        new DateTimePoint(new DateTime(2013, 1, 1), .742)
                    },
                    LineSmoothness = 0
                }
            };

            XFormatter = val => new DateTime((long) val).ToString("yyyy");
            YFormatter = val => val.ToString("N") + " M";

            DataContext = this;
        }

        public SeriesCollection SeriesCollection { get; set; }
        public Func<double, string> XFormatter { get; set; }

        public Func<double, string> YFormatter
        {
            get { return _yFormatter; }
            set
            {
                _yFormatter = value;
                OnPropertyChanged();
            }
        }

        public StackMode StackMode { get; set; }

        private void ChangeStackModeOnClick(object sender, RoutedEventArgs e)
        {
            foreach (var series in SeriesCollection.Cast<StackedAreaSeries>())
            {
                series.StackMode = series.StackMode == StackMode.Percentage
                    ? StackMode.Values
                    : StackMode.Percentage;
            }

            if (((StackedAreaSeries) SeriesCollection[0]).StackMode == StackMode.Values)
            {
                YFormatter = val => val.ToString("N") + " M";
            }
            else
            {
                YFormatter = val => val.ToString("P");
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged(string propertyName = null)
        {
            if (PropertyChanged != null) PropertyChanged.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}