/*
  Cassowary.net: an incremental constraint solver for .NET
  (http://lumumba.uhasselt.be/jo/projects/cassowary.net/)
  
  Copyright (C) 2005  Jo Vermeulen (jo.vermeulen@uhasselt.be)
  
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public License
  as published by the Free Software Foundation; either version 2.1
  of  the License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

using System;

namespace Cassowary
{
  public class ClLinearEquation : ClLinearConstraint
  {
    public ClLinearEquation(ClLinearExpression cle,
                            ClStrength strength,
                            double weight) : base(cle, strength, weight)
    {}

    public ClLinearEquation(ClLinearExpression cle,
                            ClStrength strength) : base(cle, strength)
    {}

    public ClLinearEquation(ClLinearExpression cle) : base(cle)
    {}

    public ClLinearEquation(ClAbstractVariable clv,
                            ClLinearExpression cle,
                            ClStrength strength,
                            double weight) : base(cle, strength, weight)
    {
      _expression.AddVariable(clv, -1.0);
    }

    public ClLinearEquation(ClAbstractVariable clv,
                            ClLinearExpression cle,
                            ClStrength strength) : this(clv, cle, strength, 1.0)
    {}

    public ClLinearEquation(ClAbstractVariable clv, 
                            ClLinearExpression cle) : this(clv, cle, ClStrength.Required, 1.0)
    {}

    public ClLinearEquation(ClAbstractVariable clv, 
                            double val, 
                            ClStrength strength, 
                            double weight) : base(new ClLinearExpression(val), strength, weight)
    {
      _expression.AddVariable(clv, -1.0);
    }

    public ClLinearEquation(ClAbstractVariable clv,
                            double val,
                            ClStrength strength) : this(clv, val, strength, 1.0)
    {}

    public ClLinearEquation(ClAbstractVariable clv,
                            double val) : this(clv, val, ClStrength.Required, 1.0)
    {}

    public ClLinearEquation(ClLinearExpression cle,
                            ClAbstractVariable clv,
                            ClStrength strength,
                            double weight) : base((ClLinearExpression) cle.Clone(), strength, weight)
    {
      _expression.AddVariable(clv, -1.0);
    }

    public ClLinearEquation(ClLinearExpression cle,
                            ClAbstractVariable clv,
                            ClStrength strength) : this(cle, clv, strength, 1.0)
    {}

    public ClLinearEquation(ClLinearExpression cle, ClAbstractVariable clv) : this(cle, clv, ClStrength.Required, 1.0)
    {}

    public ClLinearEquation(ClLinearExpression cle1,
                            ClLinearExpression cle2,
                            ClStrength strength,
                            double weight) : base((ClLinearExpression) cle1.Clone(), strength, weight)
    {
      _expression.AddExpression(cle2, -1.0);
    }

    public ClLinearEquation(ClLinearExpression cle1,
                            ClLinearExpression cle2,
                            ClStrength strength) : this(cle1, cle2, strength, 1.0)
    {}
        
    public ClLinearEquation(ClLinearExpression cle1, 
                            ClLinearExpression cle2) : this(cle1, cle2, ClStrength.Required, 1.0)
    {}

    public override string ToString()
    {
      return base.ToString() + " = 0)";
    }
  }
}