--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Stocks/Stocks.Common/Models/Price.cs	Mon Feb 20 13:52:35 2012 +0700
@@ -0,0 +1,129 @@
+using Stocks.Common.Core;
+using System.Collections;
+using System;
+using System.Collections.Generic;
+
+namespace Stocks.Common.Models
+{
+  public class Price : IEquatable<Price>, IComparable<Price>, IComparable
+  {
+    public string Symbol { get; set; }
+    public decimal CurrentPrice { get; set; }
+    public decimal PreviousPrice { get; set; }
+
+    public Price()
+    {
+    }
+
+    public Price(string symbol, decimal currentPrice, decimal previousPrice)
+      : this()
+    {
+      Symbol = symbol;
+      CurrentPrice = currentPrice;
+      PreviousPrice = previousPrice;
+    }
+
+    public override bool Equals(object obj)
+    {
+      if (obj is Price)
+        return Equals(obj as Price);
+      else
+        return false;
+    }
+
+    public bool Equals(Price other)
+    {
+      return (Symbol == other.Symbol
+        && CurrentPrice == other.CurrentPrice
+        && PreviousPrice == other.PreviousPrice);
+    }
+
+    public int CompareTo(Price other)
+    {
+      return Symbol.CompareTo(other.Symbol);
+    }
+
+    public int CompareTo(Price other, PriceComparisonType comparisonType)
+    {
+      switch (comparisonType)
+      {
+        case PriceComparisonType.NotSet:
+        case PriceComparisonType.Symbol:
+          return Symbol.CompareTo(other.Symbol);
+        case PriceComparisonType.CurrentPrice:
+          return CurrentPrice.CompareTo(other.CurrentPrice);
+        case PriceComparisonType.PreviousPrice:
+          return PreviousPrice.CompareTo(other.PreviousPrice);
+        default:
+          throw new Exception("Unknown comparison type");
+      }
+    }
+
+    public int CompareTo(object obj)
+    {
+      Price other;
+      if (obj is Price)
+        other = obj as Price;
+      else
+        throw new ArgumentException("obj is not a Price");
+
+      return CompareTo(other);
+    }
+    public override int GetHashCode()
+    {
+      int hash = 13;
+      hash = (hash * 7) + Symbol.GetHashCode();
+      hash = (hash * 7) + CurrentPrice.GetHashCode();
+      hash = (hash * 7) + PreviousPrice.GetHashCode();
+      return hash;
+    }
+
+    public static bool operator ==(Price lhs, Price rhs)
+    {
+      if (System.Object.ReferenceEquals(lhs, rhs))
+        return true;
+
+      if (((object)lhs == null) || ((object)rhs == null))
+        return false;
+
+      return lhs.Symbol == rhs.Symbol
+        && lhs.CurrentPrice == rhs.CurrentPrice
+        && lhs.PreviousPrice == rhs.PreviousPrice;
+    }
+
+    public static bool operator !=(Price lhs, Price rhs)
+    {
+      return !(lhs == rhs);
+    }
+
+
+    public class PriceComparer : IComparer<Price>, IComparer
+    {
+      public PriceComparisonType ComparisonMethod { get; set; }
+
+      public int Compare(Price x, Price y)
+      {
+        return x.CompareTo(y, ComparisonMethod);
+      }
+
+      public int Compare(object x, object y)
+      {
+        Price lhs, rhs;
+
+        if (x is Price)
+          lhs = x as Price;
+        else
+          throw new ArgumentException("x is not a Price");
+
+        if (y is Price)
+          rhs = y as Price;
+        else
+          throw new ArgumentException("y is not a Price");
+
+        return lhs.CompareTo(rhs, ComparisonMethod);
+      }
+    }
+  }
+
+  public enum PriceComparisonType { NotSet = 0, Symbol, CurrentPrice, PreviousPrice }
+}