using System;
using System.Collections.Generic;
using System.Linq;
using System.Data.Linq;
using System.Data.Linq.Mapping;
using System.Text;

namespace HeuristicLab.Modeling.SQLiteBackend {
  [Table(Name = "Variable")]
  public class Variable {
    public Variable() {
      modelsPredictingThisVariable = new EntitySet<Model>(attach_Model, detach_Model);
    }

    private int id;
    [Column(Storage = "id", DbType = "integer", IsPrimaryKey = true, IsDbGenerated = true, UpdateCheck = UpdateCheck.Never)]
    public int Id {
      get { return this.id; }
      private set { this.id = value; }
    }

    private string name;
    [Column(Storage = "name", DbType = "VarChar(50) NOT NULL", CanBeNull = false)]
    public string Name {
      get { return this.name; }
      private set { this.name = value; }
    }

    private EntitySet<Model> modelsPredictingThisVariable;
    [Association(Storage = "modelsPredictingThisVariable", ThisKey = "Id", OtherKey = "TargetVariableId")]
    public EntitySet<Model> ModelsPredictingThisVariable {
      get {
        if (modelsPredictingThisVariable.HasLoadedOrAssignedValues)
          return modelsPredictingThisVariable;
        return null;
      }
      set {
        modelsPredictingThisVariable.Assign(value);
      }
    }

    private void attach_Model(Model model) {
      model.TargetVariable = this;
    }

    private void detach_Model(Model model) {
      model.TargetVariable = null;
    }

    public IEnumerable<Model> ModelsUsingThisVariable {
      get {
        using (ModelingDataContext ctx = new ModelingDataContext()) {
          var x = from inputVariable in ctx.InputVariables
                  where inputVariable.Variable == this
                  select inputVariable.Model;
          return x.AsEnumerable();
        }
      }
    }
  }
}