var DomWriter = function (target, namespace) {
    var instance = this;
    var template = namespace;

    var coalesce = function( value, defaultValue ) {
        return typeof(value) != 'undefined' ?
            value : defaultValue;
    };

    this.isObject = function( value ) {
        return typeof(value) === 'object';
    };

    this.addSubscription = function( path, element ) {
        postal.subscribe( "binding", path, function( msg ) {
            instance.write( path, msg );
        });
        if( _(instance[path]).isUndefined() ) {
            instance[path] = element;
        }
    };

    this.crawl = function( namespace, element, callback ) {
        _(element)
            .chain()
            .keys()
            .each( function( key ) {
                var child = element[key];
                var fqn = namespace === "" ?
                    key : namespace + "." + key;
                callback( namespace, key, child );
                if( !_.isNull( child ) && instance.isObject( child ) ) {
                    instance.crawl( fqn, child, callback );
                }
        });
    };

    this.domCrawl = function( namespace, element, callback ) {
        var id = coalesce( element["id"], "" );
        var fqn = namespace == "" ?
            id : ( id === "" ? namespace : namespace + "." + id );
        callback( fqn, id, element );
        if( element.children !== undefined &&
            element.children.length > 0 ) {
            _(element.children)
                .chain()
                .each( function( child ) {
                        instance.domCrawl(
                            fqn,
                            child,
                            callback );
                });
        }
    };

    this.domCrawl( "", target[0], function( namespace, key, child ) {
        var prefix = template + ".";
        var member = namespace === template ?
            namespace : namespace.replace( prefix, "", "gi");
        instance.addSubscription( member, child );
    });

    this.write = function( path, value ) {
        element = this[path];
        this[$(element)[0].tagName.toLowerCase()]
            ( path, element, value );
    };

    this.div = function( fqn, element, value ) {
        if( instance.isObject( value ) ) {
            instance.crawl( "", value, function( namespace, key, child ) {
                instance.write(
                    namespace === "" ? key : namespace + "." + key,
                    child );
            });
        }
        else {
            $(element).text( value );
        }
    };

    this.span = function( fqn, element, value ) {
        $(element).text( value );
    };

    this.input = function( fqn, element, value ) {
        $(element).val( value );
    };

    this.ul = function( fqn, element, value ) {
        var children = $(element).children("li");
        if( children.length < value.length ) {
            $(element).empty();
            var li = children[0];
            var indx = 0;
            _(value)
                .each( function( child ) {
                    var newLi = $(li)
                        .clone()
                        .attr( "id", indx )
                        .appendTo( element );
                    instance[ fqn + "." + indx ] = newLi[0];

                    instance.domCrawl(
                        fqn,
                        newLi[0],
                        function( namespace, key, child ) {
                            var prefix = template + ".";
                            var member = namespace === template ?
                                namespace : namespace.replace( prefix, "", "gi");
                            instance.addSubscription( member, child );
                        }
                    );

                    indx++;
                });
        }
    };

    this.li = function( fqn, element, value ) {
        $(element).text( value );
    };
};