using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Xml;
using ESRI.ArcGIS.Client.Toolkit.DataSources;
using OpenEarth.DataViewer.Helpers;

namespace OpenEarth.DataViewer.Windows
{
    /// <summary>
    /// Interaction logic for LayerListBox.xaml
    /// </summary>
    public partial class KmlLayerListBox : UserControl
    {
        private readonly List<LayerWrapper> mapLayers;

        public KmlLayerListBox()
        {
            InitializeComponent();
            mapLayers = new List<LayerWrapper>();
            if (CreateDataSet())
            {
                LinkDataSet();
            }
        }

        public static DependencyProperty MessageProperty = DependencyProperty.Register("ItemsSource", typeof(Array), typeof(KmlLayerListBox));

        private bool CreateDataSet()
        {
            var doc = new XmlDocument();
            try
            {
                doc.Load("KMLLayers.xml");
                var elements = doc.SelectNodes("//layers/layer");
                if (elements != null)
                {
                    foreach (XmlElement element in elements)
                    {
                        var mapLayer = new LayerWrapper
                                           {
                                               Layer = new KmlLayer
                                                           {
                                                               Opacity = 0.5,
                                                               Visible = true
                                                           }
                                           };
                        foreach (XmlNode child in element.ChildNodes)
                        {
                            if (child.Name.ToLower() == "name")
                            {
                                mapLayer.Name = child.ChildNodes[0].Value;
                            }
                            if (child.Name.ToLower() == "id")
                            {
                                mapLayer.Layer.ID = child.ChildNodes[0].Value;
                            }
                            if (child.Name.ToLower() == "url")
                            {
                                ((KmlLayer)mapLayer.Layer).Url = new Uri(child.ChildNodes[0].Value);
                            }   
                            if (child.Name.ToLower() == "source")
                            {
                                mapLayer.Source = child.ChildNodes[0].Value;
                            }
                            if (child.Name.ToLower() == "var")
                            {
                                mapLayer.Variable = child.ChildNodes[0].Value;
                            }
                        }
                        mapLayers.Add(mapLayer);
                    }
                }
                return true;
            }
            catch (Exception ex)
            {
                textBoxError.Visibility = Visibility.Visible;
                textBoxError.Text = ex.Message;
                return false;
            }
        }

        private void LinkDataSet()
        {
            SetValue(MessageProperty, mapLayers.Select(layer => layer.Name).ToList().ToArray());
        }

        private void ListBoxSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            var selection = ((ListBox)sender).SelectedItems[0];
            if (selection != null)
            {
                LayerWrapper wrapper = null;
                foreach (var layer in mapLayers.Where(layer => layer.Name == (string)selection))
                {
                    wrapper = layer;
                }
                InvokeOverlayChanged(wrapper);
            }
        }

        public event OverlayChange OverlayChanged;

        public delegate void OverlayChange(LayerWrapper wrapper);

        public void InvokeOverlayChanged(LayerWrapper wrapper)
        {
            var handler = OverlayChanged;
            if (handler != null)
            {
                handler(wrapper);
            }
        }
    }
}