Caml Query Builder

CamlQueryBuilder.js

var CamlQueryBuilder = function() {

};
CamlQueryBuilder.prototype.withExactValues = function(fieldValues) {
    
    this.exactFieldValues = fieldValues;
    this.doExactQuery = true;
};
CamlQueryBuilder.prototype.thatContains = function(fields, values) {

    this.containsFields = fields;
    this.containsValues = values;
    this.doContainsQuery = true;
};
CamlQueryBuilder.prototype.build = function() {
    var self = this;
    var caml = '';

    if(!self.doExactQuery && !self.doContainsQuery) return '';

    caml = "<Query><Where>";

    if(self.doExactQuery && self.doContainsQuery) {
        caml += "<And>";
    }
    if(self.doExactQuery) {
        if (self.exactFieldValues === undefined || self.exactFieldValues.length === 0)  return '';
        
        if (self.exactFieldValues.length > 1) {
            caml += "<And>";
        }
        $.each(self.exactFieldValues, function (i, e) {

            caml += '<Eq><FieldRef Name="' + e.id + '" /><Value Type="Text">' + e.value + '</Value></Eq>';
        });
        if (self.exactFieldValues.length > 1) {
            caml += "</And>";
        }
    }
    if(self.doContainsQuery) {
        if (self.containsFields.length > 1 || self.containsValues.length > 1) {
            caml += "<Or>";
        }
        $.each(self.containsFields, function (i, field) {

            $.each(self.containsValues, function (i, value) {

                caml += '<Contains><FieldRef Name="' + field + '" /><Value Type="Text">' + value + '</Value></Contains>';    
            });
        });
        if (self.containsFields.length > 1 || self.containsValues.length > 1) {
            caml += "</Or>";
        }
        
    }
    if(self.doExactQuery && self.doContainsQuery) {
        caml += "</And>";
    }
    caml += "</Where></Query>";
    return caml;
};