osmapi.xmlbuilder

def _XmlBuild(ElementType, ElementData, WithHeaders=True, data=None):  # noqa
    xml = ""
    if WithHeaders:
        xml += "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
        xml += "<osm version=\"0.6\" generator=\""
        xml += data._created_by + "\">\n"

    # <element attr="val">
    xml += "  <" + ElementType
    if "id" in ElementData:
        xml += " id=\"" + str(ElementData["id"]) + "\""
    if "lat" in ElementData:
        xml += " lat=\"" + str(ElementData["lat"]) + "\""
    if "lon" in ElementData:
        xml += " lon=\"" + str(ElementData["lon"]) + "\""
    if "version" in ElementData:
        xml += " version=\"" + str(ElementData["version"]) + "\""
    visible_str = str(ElementData.get("visible", True)).lower()
    xml += " visible=\"" + visible_str + "\""
    if ElementType in ["node", "way", "relation"]:
        xml += " changeset=\"" + str(data._CurrentChangesetId) + "\""
    xml += ">\n"

    # <tag... />
    for k, v in ElementData.get("tag", {}).items():
        xml += "    <tag k=\"" + _XmlEncode(k)
        xml += "\" v=\"" + _XmlEncode(v) + "\"/>\n"

    # <member... />
    for member in ElementData.get("member", []):
        xml += "    <member type=\"" + member["type"]
        xml += "\" ref=\"" + str(member["ref"])
        xml += "\" role=\"" + _XmlEncode(member["role"])
        xml += "\"/>\n"

    # <nd... />
    for ref in ElementData.get("nd", []):
        xml += "    <nd ref=\"" + str(ref) + "\"/>\n"

    # </element>
    xml += "  </" + ElementType + ">\n"

    if WithHeaders:
        xml += "</osm>\n"

    return xml.encode("utf8")


def _XmlEncode(text):
    return (
        text
        .replace("&", "&amp;")
        .replace("\"", "&quot;")
        .replace("<", "&lt;")
        .replace(">", "&gt;")
    )


def _GetXmlValue(DomElement, tag):
    try:
        elem = DomElement.getElementsByTagName(tag)[0]
        return elem.firstChild.nodeValue
    except Exception:
        return None