function GroupList() {

  lastChange=0;
  
  this.loadFromLocalStorage=function() {
    if (jQuery.type(localStorage.groups)!='undefined') {
      try {
        var data=JSON.parse(localStorage.groups);
        this.lastChange=data.lastChange;
        for (el in data.groups) {
          this[el]=new Group(el,false,data.groups[el]);
        }
      }
      catch(e) {
        for (el in this) {
          if (this.isGroup(this[el])) {
            delete this[el];
          }
        }
        myconfirm('Erreur en chargeant les données locales. On les purges ?',
          function(data) {
            delete localStorage.groups;
            location.reload();
          }
        );
      }
    }
  }

  this.export=function() {
    return {
      'lastChange': this.lastChange,
      'groups': this.each(function(idx,group) {
        return group.export();
      })
    };
  }

  this.import=function(groups) {
    ret={};
    for (el in this) {
      if (this.isGroup(this[el])) {
        delete ret[el];
      }
    }
    this.lastChange=groups.lastChange;
    for (el in groups.groups) {
      this[el]=new Group(el,false,groups.groups[el]);
    }
    return true;
  }


  this.save=function() {
    localStorage.groups=JSON.stringify(this.export());
  }

  this.each=function(fct) {
    var idx=0;
    var ret={};
    for (el in this) {
      if(this.isGroup(this[el])) {
        ret[el]=fct(idx++,this[el]);
      }
    }
    return ret;
  }

  this.count=function() {
    len=0;
    this.each(function(idx,group) {
      len=len+1;
    });
    return len;
  }

  this.isGroup=function(el) {
    return (jQuery.type(el)=='object' && jQuery.type(el.isGroup)=='function' && el.isGroup());
  }

  this.byName=function(name) {
    for (el in this) {
      if(this.isGroup(this[el])) {
        if (this[el].name==name) {
          return this[el];
        }
      }
    }
    return false;
  }


  this.removeGroup=function(uuid) {
    if (this.isGroup(this[uuid])) {
      delete this[uuid];
      return true;
    }
    return false;
  }

  this.balances=function(fct) {
    return this.each(function(idx,group) {
      bal=group.balance();
      bal.name=group.name;
      return bal;
    });
  }

  this.newGroup=function(name,uuid) {
    var uuid=uuid||generate_uuid();
    this[uuid]=new Group(uuid,name);
    return uuid;
  }

}

function Group(uuid,name,data) {
  this.uuid=uuid || generate_uuid();
  this.name=name || false;
  this.contributors={};
  this.contributions={};
  this.deletedContributions={};


  this.isGroup=function() {
    return true;
  }

  this.export=function() {
    var contributors={};
    for (email in this.contributors) {
      contributors[email]=this.contributors[email].export();
    }
    var contributions={}
    for (uuid in this.contributions) {
      contributions[uuid]=this.contributions[uuid].export();
    }
    return {
      'uuid': this.uuid,
      'name': encodeURIComponent(this.name),
      'contributors': contributors,
      'contributions': contributions,
      'deletedContributions': this.deletedContributions
    };
  }

  /*
   * Contributors
   */
  this.removeContributor=function(c) {
    delete this.contributors[c.email];
  }

  this.contributorByName=function(name) {
    for (email in this.contributors) {
      if (this.contributors[email].name == name) return this.contributors[email];
    }
    return undefined;
  }

  this.contributorByEmail=function(email) {
    if (jQuery.type(this.contributors[email])!='undefined') {
      return this.contributors[email];
    }
    return undefined;
  }

  this.addContributor=function(c) {
    this.contributors[c.email]=c;
  }

  this.replaceContributor=function(email,c) {
    delete this.contributors[email];
    this.contributors[c.email]=c;
  }

  /*
   * Contributions
   */
  this.contributionsByContributorEmail=function(email) {
    var ret=[];
    for (uuid in this.contributions) {
      if (this.contributions[uuid].contributor.email==email) {
        ret.push(this.contributions[uuid]);
      }
    }
    ret.sort(function(a,b) {
      if (a.date==b.date) {
        return 0;
      }
      else if(a.date<b.date) {
        return -1;
      }
      else {
        return 1;
      }
    });
    return ret;
  }

  this.addContribution=function(c) {
    this.contributions[c.uuid]=c;
  }

  this.updateContribution=function(uuid,c) {
    c.uuid=uuid;
    this.contributions[uuid]=c;
  }

  this.deleteContribution=function(uuid) {
    this.contributions[uuid].lastChange=new Date().getTime();
    this.deletedContributions[uuid]=this.contributions[uuid].export();
    delete this.contributions[uuid];
  }


  /*
   * Balance
   */
  this.balance=function() {
    total={}
    min=-1;
    max=0;
    for (email in this.contributors) {
      var sum=0;
      cl=this.contributionsByContributorEmail(email);
      for (idx in cl) {
        sum+=cl[idx].cost;
      }
      if (min==-1 || min>sum) {
          min=sum;
        }
      if(max<sum) {
        max=sum;
      }
      total[email]=sum;
    }
    balance={}
    var sum=0;
    for (email in total) {
      balance[email]={
        'name': this.contributors[email].name,
        'total': total[email],
        'diff': total[email]-max,
      }
      sum=sum+total[email];
    }
    return {
      'balance': balance,
      'sum': sum,
      'min': min,
      'max': max
    };
  }

  /*
   * Contructor
   */
  if (jQuery.type(data)=='object') {
    try {
      this.uuid=data.uuid;
      this.name=data.name;
      if (jQuery.type(data.contributors) == 'object') {
        for (email in data.contributors) {
          this.contributors[email]=new Contributor(
            decodeURIComponent(data.contributors[email].name),
            data.contributors[email].email
          );
        }
      }
      if (jQuery.type(data.contributions) == 'object') {
        for (uuid in data.contributions) {
          this.contributions[uuid]=new Contribution(
            this.contributorByEmail(data.contributions[uuid].contributor),
            data.contributions[uuid].cost,
            decodeURIComponent(data.contributions[uuid].title),
            data.contributions[uuid].date,
            uuid,
            data.contributions[uuid].lastChange
          );
        }
      }
      if (jQuery.type(data.deletedContributions) == 'object') {
        for (uuid in data.deletedContributions) {
          this.deletedContributions[uuid]=data.deletedContributions[uuid];
        }
      }
    }
    catch (e) {
      alert('Une erreur est survenue en chargeant le groupe '+this.name+' depuis le cache');
    }
  }
}

function Contributor(name,email) {
  this.name=name;
  this.email=email;
  this.export=function() {
    return {
      'name': encodeURIComponent(this.name),
      'email': this.email
    };
  }
}

function Contribution(contributor,cost,title,date,uuid,lastChange) {
  this.contributor=contributor;
  this.cost=cost;
  this.title=title;
  if (jQuery.type(date)!='date') {
    date=moment(date).toDate();
  }
  this.date=date;
  this.uuid=uuid || generate_uuid();
  this.lastChange=lastChange || new Date().getTime();
  this.export=function() {
    return {
      'contributor': this.contributor.email,
      'uuid': this.uuid,
      'cost': this.cost,
      'title': encodeURIComponent(this.title),
      'date': this.date.getTime(),
      'lastChange': this.lastChange,
    };
  }

  this.getTitle=function() {
    if (jQuery.type(this.title)=='string') {
      return this.title;
    }
    return '';
  }
}

function SyncServer() {
  this.url=false;
  this.email=false;
  this.password=false;
  this.logged=false;

  this.login=function(url,email,password,onsuccess,onerror) {
    this.url=url;
    this.email=email;
    this.password=password;

    try {
      jQuery.getJSON(
        this.url+'/login',
        {'email':email,'password':password},
        function(data, textStatus) {
          console.log(data);
          if (textStatus=='success') {
            if(jQuery.type(data.email) != 'undefined' && jQuery.type(data.name) != 'undefined') {
              console.log('Login success return');
              console.log(onsuccess);
              onsuccess(data);
              return true;
            }
          }
          onerror(data);
        }
      ).fail(onerror);
    }
    catch(e) {
      if(jQuery.type(onerror)=='function') {
        onerror();
      }
    }
  }

  this.subscribe=function(url,email,name,password,onsuccess,onerror) {
    this.url=url;
    this.email=email;
    this.name=name;
    this.password=password;

    try {
      jQuery.getJSON(
        this.url+'/subscribe',
        {'email':email,'name': name,'password':password},
        function(data, textStatus) {
          console.log(data);
          if (textStatus=='success') {
            if(jQuery.type(data.email) != 'undefined' && jQuery.type(data.name) != 'undefined') {
              onsuccess(data);
              return true;
            }
          }
          onerror(data);
          return false;
        }
      ).fail(onerror);
    }
    catch(e) {
      if(jQuery.type(onerror)=='function') {
        onerror();
      }
    }
  }


  this.sync=function(url,email,password,groups,onsuccess,onerror) {
    this.url=url;
    this.email=email;
    this.password=password;
    try {
      jQuery.getJSON(
        this.url+'/sync',
        {
          'email':email,
          'password':password,
          'groups': JSON.stringify(groups)
        },
        function(data, textStatus) {
          console.log(data);
          if (textStatus=='success') {
            if(jQuery.type(data.groups)) {
              console.log('Sync success return');
              onsuccess(data);
              return true;
            }
          }
          onerror(data);
        }
      ).fail(onerror);
    }
    catch(e) {
      if(jQuery.type(onerror)=='function') {
        onerror();
      }
    }
  }

}