'''
@Author: lrl
@Date: 2020-06-23 16:43:13
@Version: 1.0
'''
from xml.etree.ElementTree import ElementTree,Element


def read_xml(in_path):
    '''''读取并解析xml文件
       in_path: xml路径
       return: ElementTree'''
    tree = ElementTree()
    tree.parse(in_path)
    return tree

def write_xml(tree, out_path):
    '''''将xml文件写出
       tree: xml树
       out_path: 写出路径'''
    tree.write(out_path, encoding="utf-8", xml_declaration=True)

def if_match(node, kv_map):
    '''''判断某个节点是否包含所有传入参数属性
       node: 节点
       kv_map: 属性及属性值组成的map'''
    for key in kv_map:
        if node.get(key) != kv_map.get(key):
            return False
    return True

# ----------------search -----------------
def find_nodes(tree, path):
    '''''查找某个路径匹配的所有节点
       tree: xml树
       path: 节点路径'''
    return tree.findall(path)

def get_node_by_keyvalue(nodelist, kv_map):
    '''''根据属性及属性值定位符合的节点，返回节点
       nodelist: 节点列表
       kv_map: 匹配属性及属性值map'''
    result_nodes = []
    for node in nodelist:
        if if_match(node, kv_map):
            result_nodes.append(node)
    return result_nodes

# ---------------change ----------------------
def change_node_properties(nodelist, kv_map, is_delete=False):
    '''修改/增加 /删除 节点的属性及属性值
       nodelist: 节点列表
       kv_map:属性及属性值map'''
    for node in nodelist:
        for key in kv_map:
            if is_delete:
                if key in node.attrib:
                    del node.attrib[key]
            else:
                node.set(key, kv_map.get(key))

def change_node_text(nodelist, text, is_add=False, is_delete=False):
    '''''改变/增加/删除一个节点的文本
       nodelist:节点列表
       text : 更新后的文本'''
    for node in nodelist:
        if is_add:
            node.text += text
        elif is_delete:
            node.text = ""
        else:
            node.text = text

def create_node(tag, property_map=None, content=None):
    '''新造一个节点
       tag:节点标签
       property_map:属性及属性值map
       content: 节点闭合标签里的文本内容
       return 新节点'''
    if property_map is not None:
        element = Element(tag, property_map)
    if content is not None:
        element.text = content
    return element

def add_child_node(nodelist, element):
    '''''给一个节点添加子节点
       nodelist: 节点列表
       element: 子节点'''
    for node in nodelist:
        node.append(element)


def del_node_by_tagkeyvalue(nodelist, tag, kv_map):
    '''''同过属性及属性值定位一个节点，并删除之
       nodelist: 父节点列表
       tag:子节点标签
       kv_map: 属性及属性值列表'''
    for parent_node in nodelist:
        children = parent_node.getchildren()
        for child in children:
            if child.tag == tag and if_match(child, kv_map):
                parent_node.remove(child)


'''    ################ 1. 读取xml文件  ##########
    tree = read_xml("test_02.xml")

    ################ 2. 属性修改 ###############
    nodes = find_nodes(tree, "processers/processer")                   # 找到父节点
    result_nodes = get_node_by_keyvalue(nodes, {"name": "BProcesser"}) # 通过属性准确定位子节点
    change_node_properties(result_nodes, {"age": "1"})                 # 修改节点属性
    change_node_properties(result_nodes, {"value": ""}, True)          # 删除节点属性

    #################  3. 节点修改 ##############
    a = create_node("person", {"age": "15", "money": "200000"}, "this is the firest content") # 新建节点
    add_child_node(result_nodes, a) # 插入到父节点之下

    ################# 4. 删除节点 ################
    del_parent_nodes = find_nodes(tree, "processers/services/service")                            # 定位父节点
    target_del_node = del_node_by_tagkeyvalue(del_parent_nodes, "chain", {"sequency": "chain1"})  # 准确定位子节点并删除之

    ################# 5. 修改节点文本 ############
    text_nodes = get_node_by_keyvalue(find_nodes(tree, "processers/services/service/chain"), {"sequency": "chain3"}) # 定位节点
    change_node_text(text_nodes, "new text")

    ################ 6. 输出到结果文件  ##########
    write_xml(tree, "./xiugai.xml")
'''
