//GetObjectMeta calls the OpenStack retrieve object metadata API using
//previously obtained token.
func GetObjectMeta(session *openstack.Session, url string) (http.Header, error) {
	resp, err := session.Head(url, nil, nil)
	if err != nil {
		return nil, err
	}
	return resp.Header, util.CheckHTTPResponseStatusCode(resp)
}

//ListObjects calls the OpenStack list object API using previously
//obtained token. "Limit", "marker", "prefix", "path", "delim" corresponds
//to the API's "limit", "marker", "prefix", "path", and "delimiter".
func ListObjects(session *openstack.Session, limit int64,
	marker, prefix, path, delim, conURL string) ([]byte, error) {
	var query url.Values = url.Values{}
	query.Add("format", "json")
	if limit > 0 {
		query.Add("limit", strconv.FormatInt(limit, 10))
	}
	if marker != "" {
		query.Add("marker", url.QueryEscape(marker))
	}
	if prefix != "" {
		query.Add("prefix", url.QueryEscape(prefix))
	}
	if path != "" {
		query.Add("path", url.QueryEscape(path))
	}
	if delim != "" {
		query.Add("delimiter", url.QueryEscape(delim))
	}
	resp, err := session.Get(conURL, &query, nil)
	if err != nil {
		return nil, err
	}
	if err = util.CheckHTTPResponseStatusCode(resp); err != nil {
		return nil, err
	}
	body, err := ioutil.ReadAll(resp.Body)
	defer resp.Body.Close()
	if err != nil {
		return []byte{}, err
	}
	return body, nil
}

//DeleteObject calls the OpenStack delete object API using
//previously obtained token.
//
//Note from API doc: "A DELETE to a versioned object removes the current version
//of the object and replaces it with the next-most current version, moving it
//from the non-current container to the current." .. "If you want to completely
//remove an object and you have five total versions of it, you must DELETE it
//five times."
func DeleteObject(session *openstack.Session, url string) (err error) {
	resp, err := session.Delete(url, nil, nil)
	if err != nil {
		return err
	}
	return util.CheckHTTPResponseStatusCode(resp)
}

//PutObject calls the OpenStack create object API using previously
//obtained token.
//url can be regular storage or CDN-enabled storage URL.
func PutObject(session *openstack.Session, fContent *[]byte, url string, headers http.Header) (err error) {
	resp, err := session.Put(url, nil, &headers, fContent)
	if err != nil {
		return err
	}
	return util.CheckHTTPResponseStatusCode(resp)
}

//SetObjectMeta calls the OpenStack API to create/update meta data for
//object using previously obtained token.
func SetObjectMeta(session *openstack.Session, url string, headers http.Header) (err error) {
	// headers.Add("X-Auth-Token", token)
	resp, err := session.Post(url, nil, &headers, zeroByte)
	if err != nil {
		return err
	}
	return util.CheckHTTPResponseStatusCode(resp)
}

//CopyObject calls the OpenStack copy object API using previously obtained
//token.  Note from API doc: "The destination container must exist before
//attempting the copy."
func CopyObject(session *openstack.Session, srcURL, destURL string) (err error) {
	var headers http.Header = http.Header{}
	headers.Add("Destination", destURL)
	resp, err := session.Request("COPY", srcURL, nil, &headers, zeroByte)
	if err != nil {
		return err
	}
	return util.CheckHTTPResponseStatusCode(resp)
}

//GetObject calls the OpenStack retrieve object API using previously
//obtained token. It returns http.Header, object / file content downloaded
//from the server, and err.
//
//Since this implementation of GetObject retrieves header info, it
//effectively executes GetObjectMeta also in addition to getting the
//object content.
func GetObject(session *openstack.Session, url string) (http.Header, []byte, error) {
	resp, err := session.Get(url, nil, nil)
	if err != nil {
		return nil, nil, err
	}
	if err = util.CheckHTTPResponseStatusCode(resp); err != nil {
		return nil, nil, err
	}
	var body []byte
	if body, err = ioutil.ReadAll(resp.Body); err != nil {
		return nil, nil, err
	}
	resp.Body.Close()
	return resp.Header, body, nil
}