using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
using System.Reflection;
using System.Windows;
using System.Windows.Media;
using Microsoft.Win32;

namespace BuzzGUI.Common.Settings
{
	public class Setting : INotifyPropertyChanged
	{
		Settings settings;
		PropertyInfo pi;

		public Setting(Settings settings, PropertyInfo pi)
		{
			this.settings = settings;
			this.pi = pi;
		}

		public string Value
		{
			get
			{
				if (Presets == null)
				{
					var v = pi.GetValue(settings, null);
					return v != null ? v.ToString() : "<null>";
				}
				else
				{
					var sel = Presets.FirstOrDefault(p => p.Item2.All(s => settings.Get(s.Item1).Equals(s.Item2)));
					return sel != null ? sel.Item1 : null;
				}
			}
			set
			{
				if (Presets == null)
				{
					string oldv = pi.GetValue(settings, null).ToString();
					if (value != oldv)
					{
						pi.SetValue(settings, TypeDescriptor.GetConverter(pi.PropertyType).ConvertFromString(value), null);
						IsModified = true;
						settings.OnPropertyChanged(Name);
						PropertyChanged.Raise(this, "Value");
					}
				}
				else
				{
					foreach (var s in Presets.First(i => i.Item1 == value).Item2)
						settings.Set(s.Item1, s.Item2);
				}
			}
		}

		public object ValueObject { get { return pi.GetValue(settings, null); } }

		public string Name { get; set; }
		public string[] Options { get; set; }
		public string Default { get; set; }
		public bool IsDefault { get { return Value == Default; } }
		public string Description { get; set; }
		public Tuple<string, Tuple<string, string>[]>[] Presets { get; set; }
		public bool IsModified { get; set; }

		public override string ToString() { return Name; }
		
		public event PropertyChangedEventHandler PropertyChanged;

	};

	public abstract class Settings : INotifyPropertyChanged
	{
		public event PropertyChangedEventHandler PropertyChanged;
		string registryLocation;

		IEnumerable<PropertyInfo> Properties { get { return from x in GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance) where x.DeclaringType != typeof(Settings) select x; } }
		public List<Setting> List = new List<Setting>();

		public void OnPropertyChanged(string name)
		{
			PropertyChanged.Raise(this, name);
		}

		public void Set(string name, string value)
		{
			List.First(s => s.Name == name).Value = value;
		}

		public void Set(string name, int value)
		{
			Set(name, value.ToString());
		}

		public void Set(string name, bool value)
		{
			Set(name, value ? "True" : "False");
		}

		public object Get(string name)
		{
			return List.First(s => s.Name == name).Value;
		}

		public Settings()
		{
			var t = GetType();

			foreach (var p in Properties)
			{
				var decl = p.GetCustomAttributes(false).FirstOrDefault(z => z.GetType() == typeof(BuzzSetting)) as BuzzSetting;
				if (decl != null)
					p.SetValue(this, decl.DefaultValue, null);

				Setting s = new Setting(this, p)
				{
					Name = p.Name,
					Default = decl != null && decl.DefaultValue != null ? decl.DefaultValue.ToString() : "",
					Description = decl.Description,
				};

				if (decl.Type == BuzzSettingType.FontFamily)
					s.Options = Fonts.SystemFontFamilies.Select(ff => ff.Source).OrderBy(n => n).ToArray();
				else if (decl.Type == BuzzSettingType.FontStyle)
					s.Options = typeof(FontStyles).GetProperties(BindingFlags.Public | BindingFlags.Static).Select(fi => fi.Name).ToArray();
				else if (decl.Type == BuzzSettingType.FontWeight)
					s.Options = typeof(FontWeights).GetProperties(BindingFlags.Public | BindingFlags.Static).Select(fi => fi.Name).ToArray();
				else if (decl.Type == BuzzSettingType.FontStretch)
					s.Options = typeof(FontStretches).GetProperties(BindingFlags.Public | BindingFlags.Static).Select(fi => fi.Name).ToArray();
				else if (p.PropertyType == typeof(int))
					s.Options = Enumerable.Range(decl.Minimum, decl.Maximum - decl.Minimum + 1).Select(x => x.ToString()).ToArray();
				else if (p.PropertyType == typeof(bool))
					s.Options = new[] { "True", "False" };
				else if (p.PropertyType.IsEnum)
					s.Options = p.PropertyType.GetFields(BindingFlags.Public | BindingFlags.Static).Select(fi => fi.Name).ToArray();

				if (decl.Presets != null)
				{
					s.Options = decl.Presets.Split(null).Select(ol => ol.First() as string).ToArray();
					s.Presets = decl.Presets.Split(null).Select(ol => Tuple.Create(
						ol.First() as string, 
						ol.Skip(1).SelectFromTwo((k, v) => Tuple.Create(k as string, v.ToString())).ToArray()))
						.ToArray();
				}

				List.Add(s);
			}

			registryLocation = Global.RegistryRoot + "BuzzGUI\\" + t.Name;
			Load();

		}

		public void Load()
		{
			RegistryKey key = Registry.CurrentUser.OpenSubKey(registryLocation);
			if (key == null) key = Registry.CurrentUser.CreateSubKey(registryLocation);

			foreach (var p in List)
			{
				object v = key.GetValue(p.Name);
				if (v != null)
				{
					try
					{
						p.Value = v.ToString();
						p.IsModified = false;
					}
					catch (Exception) {}

				}
				
			}
		}

		public void Save()
		{
			RegistryKey key = Registry.CurrentUser.OpenSubKey(registryLocation, true);
			if (key == null) key = Registry.CurrentUser.CreateSubKey(registryLocation);

			foreach (var p in List)
			{
				if (p.IsModified && p.ValueObject != null)
				{
					key.SetValue(p.Name, p.ValueObject);
					p.IsModified = false;
				}
			}
		}

	}
}