-- coding: utf-8 --

"""
批量编码转换，用于批量转换文件的编码，支持utf-8,utf-8-bom,gb2312,gbk编码之间的转化，其他编码暂时没有测试

src_dir = "../" -->  指定要转换的文件夹路径，支持当前路径
tag_type = "utf-8-sig" --> 指定目标转换格式
type_filter = [".cpp", ".h"] --> 指定需要转换的文件类型

注意：utf-8-bom请写成utf-8-sig
"""

import os
import codecs
import chardet

def utf8_conversion(f_context, code_type):

if code_type.lower() == "utf-8":
    return f_context
elif code_type.lower() == "utf-8-bom" or code_type.lower() == "utf-8-sig":
    return codecs.BOM_UTF8 + f_context
else:
    return f_context.decode("utf-8").encode(code_type)

def conversion_to_utf8(f_context, code_type):

if code_type.lower() == "utf-8":
    return f_context
elif code_type.lower() == "utf-8-bom" or code_type.lower() == "utf-8-sig":
    return f_context[3:]
else:
    return f_context.decode(code_type).encode("utf-8")

def file_code_conversion(file_name, tag_code_type):

src_file = open(file_name, "rb")
file_context = src_file.read()
src_file.close()

if file_context == "":
    print (file_name + "  --  empty file")
    return

code_type = chardet.detect(file_context)["encoding"]
if code_type.lower() == tag_code_type.lower():
    print (file_name + "  --  escape file")
    return
else:
    print (file_name + ("  --  converted from %s into %s" % (code_type, tag_code_type)))
    tag_utf8_context = conversion_to_utf8(file_context, code_type)
    tag_context = utf8_conversion(tag_utf8_context, tag_code_type)
    tag_file = open(file_name, "wb")
    tag_file.write(tag_context)
    tag_file.close()

if name == "__main__":

src_dir = "."
tag_type = "utf-8"
type_filter = [".cpp", ".h", ".hpp", ".cxx"]

for dir_path, dirs, files in os.walk(src_dir):
    for name in files:
        if os.path.splitext(name)[1] in type_filter:
            file_code_conversion(os.path.join(dir_path, name), tag_type)