# Copyright(c) 2017, Intel Corporation
#
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import json
from . import constants
import struct
from collections import OrderedDict

"""  This is the entrypoint for generating the metadata
"""


def get_metadata(afu_json):
    ret_list = []

    ret_list.extend(list(constants.METADATA_GUID))

    if len(afu_json) != 0:
        ret_list.extend(pack_int_to_buf(len(json.dumps(afu_json))))
        ret_list.extend(list(json.dumps(afu_json)))

    else:
        ret_list.extend(pack_int_to_buf(0))

    return ret_list


def pack_int_to_buf(val):
    pack_format = "<I"
    buf = struct.pack(pack_format, val)
    return list(buf)