# vim: set encoding=utf-8

#  Copyright (c) 2016 Intel Corporation 
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#


def drop_rows(self, predicate):

    """
    Drop the rows of dicom metadata and pixeldata frames using  given predicate

    Parameters
    ----------

    :param predicate: predicate to apply on filter


    Examples
    --------

        >>> dicom_path = "../datasets/dicom_uncompressed"

        >>> dicom = tc.dicom.import_dcm(dicom_path)

        >>> dicom.metadata.count()
        3

        >>> dicom.metadata.inspect(truncate=30)
        [#]  id  metadata
        =======================================
        [0]   0  
            
                AAE=
                1.2.840.10008.5.1.4.1.1.4
                1.3.6.1.4.1.14519.5.2.1.7308.2101.234736319276602547946349519685
                ...

        >>> import xml.etree.ElementTree as ET

        #sample custom filter function
        >>> def drop_meta(tag_name, tag_value):
        ...    def _drop_meta(row):
        ...        root = ET.fromstring(row["metadata"])
        ...        for attribute in root.findall('DicomAttribute'):
        ...            keyword = attribute.get('keyword')
        ...            if attribute.get('keyword') is not None:
        ...                if attribute.find('Value') is not None:
        ...                    value = attribute.find('Value').text
        ...                    if keyword == tag_name and value == tag_value:
        ...                        return True
        ...    return _drop_meta

        >>> tag_name = "SOPInstanceUID"

        >>> tag_value = "1.3.6.1.4.1.14519.5.2.1.7308.2101.234736319276602547946349519685"

        >>> dicom.drop_rows(drop_meta(tag_name, tag_value))

        >>> dicom.metadata.count()
        2

        #After filter
        >>> dicom.metadata.inspect(truncate=30)
        [#]  id  metadata
        =======================================
        [0]   1  >> dicom.pixeldata.inspect(truncate=30)
        [#]  id  imagematrix
        ===========================================================
        [0]   1  [[   0.    0.    0. ...,    0.    0.    0.]
        [   0.   70.   85. ...,  215.  288.  337.]
        [   0.   63.   72. ...,  228.  269.  317.]
        ...,
        [   0.   42.   40. ...,  966.  919.  871.]
        [   0.   42.   33. ...,  988.  887.  860.]
        [   0.   46.   38. ...,  983.  876.  885.]]
        [1]   2  [[    0.     0.     0. ...,     0.     0.     0.]
        [    0.   111.   117. ...,   159.   148.   135.]
        [    0.   116.   111. ...,   152.   138.   139.]
        ...,
        [    0.    49.    18. ...,  1057.   965.   853.]
        [    0.    42.    20. ...,  1046.   973.   891.]
        [    0.    48.    26. ...,  1041.   969.   930.]]

    """

    def inverted_predicate(row):
        return not predicate(row)

    self.metadata.filter(inverted_predicate)
    filtered_id_frame = self.metadata.copy(columns= "id")
    self._pixeldata = filtered_id_frame.join_inner(self.pixeldata, "id")