using System;
using System.Windows.Forms;
using System.Xml;
using System.Xml.Linq;
using System.Linq;
using System.Globalization;

namespace CurrencyInfo
{
  public partial class Form1 : Form
  {
    public Form1()
    {
      InitializeComponent();
    }

    /// <summary>Tägliche Währungskurse (Mo-Fr) der Europäischen Zentralbank</summary>
    string uriDailyXml = "http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml";
    
    private void Form1_Load(object sender, EventArgs e)
    {
      XElement cubes = XElement.Load(uriDailyXml);
      var cubs =
        from el in cubes.Descendants()
        where el.Name.LocalName == "Cube" &&
              el.Attribute("time") != null
        select new
        {
          Datum = DateTime.Parse(el.Attribute("time").Value),
          Raten =
            from d in el.Descendants()
            select new
            {
              Name = CurrencyName(d.Attribute("currency").Value),
              ISOCode = d.Attribute("currency").Value,
              Rate = XmlConvert.ToDouble(d.Attribute("rate").Value)
            }
        };

      var kurse = cubs.ToList()[0];

      FlowLayoutPanel fp = new FlowLayoutPanel();
      fp.Dock = DockStyle.Fill; Controls.Add(fp);
      Label lbl = new Label(); lbl.Text = "Währungskurse vom:";
      lbl.AutoSize = true; lbl.Margin = lblPadding;
      fp.Controls.Add(lbl);

      TextBox tb = new TextBox(); tb.Width = txtWidth;
      tb.Text = kurse.Datum.ToLongDateString();
      fp.Controls.Add(tb);

      DataGridView dgv = new DataGridView();
      dgv.DataSource = kurse.Raten.ToList();
      dgv.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;
      fp.Controls.Add(dgv); dgv.Width = Width - widthAbzug;
      dgv.Height = Height - heightAbzug; 
    }

    const int heightAbzug = 70;
    const int widthAbzug = 20;
    const int txtWidth = 140;
    Padding lblPadding = new Padding(5, 6, 0, 0);

    CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.SpecificCultures);

    protected string CurrencyName(string isoCode)
    {
      // .NET Codes sind hier nicht 100% aktuell:
      // http://www.oanda.com/site/help/iso_code.shtml
      switch (isoCode)
      {
        case "BGN": isoCode = "BGL"; break;
        case "RON": isoCode = "ROL"; break;
        case "RUB": isoCode = "RUR"; break;
        default: break;
      }
      foreach (CultureInfo ci in cultures)
      {
        RegionInfo ri = new RegionInfo(ci.LCID);
        if (ri.ISOCurrencySymbol == isoCode) return ri.CurrencyEnglishName;
      }
      return null;
    }
  }
}