Source code for snake.mrd_utils.utils

"""Utils for the MRD format."""

import hashlib
import base64
import pickle
from enum import IntFlag
from typing import Any
import numpy as np
from numpy.typing import NDArray




def get_waveform_id(input_string: str) -> int:
    """
    Generate a unique id from an input string.

    The generated id is guaranteed to be bigger than 1024 and smaller than 2^16.

    Parameters
    ----------
    input_string : str
        The input string from which to generate the unique id.

    Returns
    -------
    int
       Unique id generated from the input string.

    Examples
    --------
    >>> generate_unique_id('hello_world')
    32767
    >>> generate_unique_id('this_is_a_test')
    20481
    """
    # Convert the input string to a hash digest
    hash_object = hashlib.md5(input_string.encode())
    hash_digest = int(hash_object.hexdigest(), 16)

    # Ensure the id is bigger than 1024 and smaller than 2^16
    unique_id = hash_digest % (2**16 - 1024) + 1024

    return unique_id





def obj2b64encode(f: Any) -> bytes:
    """Return the base64 encoded pickle of a python object."""
    return base64.b64encode(pickle.dumps(f))





def b64encode2obj(s: str) -> Any:
    """Load a base64 string as a python object."""
    return pickle.loads(base64.b64decode(s))





def serialize_array(arr: NDArray) -> str:
    """Serialize the array for mrd compatible format."""
    return "__".join(
        [
            base64.b64encode(arr.tobytes()).decode(),
            str(arr.shape),
            str(arr.dtype),
        ]
    )





def unserialize_array(s: str) -> NDArray:
    """Unserialize the array for mrd compatible format."""
    data, shape, dtype = s.split("__")
    shape = eval(shape)  # FIXME
    return np.frombuffer(base64.b64decode(data.encode()), dtype=dtype).reshape(*shape)



# fmt: off


class ACQ(IntFlag):
    """Acquisition flags of MRD as an IntFlags."""

    FIRST_IN_ENCODE_STEP1               = 1 << 0
    LAST_IN_ENCODE_STEP1                = 1 << 1
    FIRST_IN_ENCODE_STEP2               = 1 << 2
    LAST_IN_ENCODE_STEP2                = 1 << 3
    FIRST_IN_AVERAGE                    = 1 << 4
    LAST_IN_AVERAGE                     = 1 << 5
    FIRST_IN_SLICE                      = 1 << 6
    LAST_IN_SLICE                       = 1 << 7
    FIRST_IN_CONTRAST                   = 1 << 8
    LAST_IN_CONTRAST                    = 1 << 9
    FIRST_IN_PHASE                      = 1 << 10
    LAST_IN_PHASE                       = 1 << 11
    FIRST_IN_REPETITION                 = 1 << 12
    LAST_IN_REPETITION                  = 1 << 13
    FIRST_IN_SET                        = 1 << 14
    LAST_IN_SET                         = 1 << 15
    FIRST_IN_SEGMENT                    = 1 << 16
    LAST_IN_SEGMENT                     = 1 << 17
    IS_NOISE_MEASUREMENT                = 1 << 18
    IS_PARALLEL_CALIBRATION             = 1 << 19
    IS_PARALLEL_CALIBRATION_AND_IMAGING = 1 << 20
    IS_REVERSE                          = 1 << 21
    IS_NAVIGATION_DATA                  = 1 << 22
    IS_PHASECORR_DATA                   = 1 << 23
    LAST_IN_MEASUREMENT                 = 1 << 24
    IS_HPFEEDBACK_DATA                  = 1 << 25
    IS_DUMMYSCAN_DATA                   = 1 << 26
    IS_RTFEEDBACK_DATA                  = 1 << 27
    IS_SURFACECOILCORRECTIONSCAN_DATA   = 1 << 28
    IS_PHASE_STABILIZATION_REFERENCE    = 1 << 29
    IS_PHASE_STABILIZATION              = 1 << 30
    COMPRESSION1                        = 1 << 52
    COMPRESSION2                        = 1 << 53
    COMPRESSION3                        = 1 << 54
    COMPRESSION4                        = 1 << 55
    USER1                               = 1 << 56
    USER2                               = 1 << 57
    USER3                               = 1 << 58
    USER4                               = 1 << 59
    USER5                               = 1 << 60
    USER6                               = 1 << 61
    USER7                               = 1 << 62
    USER8                               = 1 << 63

# fmt: on