# Copyright 2016 The TensorFlow Authors. All Rights Reserved.
#
# 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.
# ==============================================================================
"""A simple script for inspect checkpoint files."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import argparse
import sys

import numpy as np

from tensorflow.python import pywrap_tensorflow
from tensorflow.python.platform import app
from tensorflow.python.platform import flags

FLAGS = None


def print_tensors_in_checkpoint_file(file_name, tensor_name, all_tensors):
    """Prints tensors in a checkpoint file.

    If no `tensor_name` is provided, prints the tensor names and shapes
    in the checkpoint file.

    If `tensor_name` is provided, prints the content of the tensor.

    Args:
        file_name: Name of the checkpoint file.
        tensor_name: Name of the tensor in the checkpoint file to print.
        all_tensors: Boolean indicating whether to print all tensors.
    """
    try:
        reader = pywrap_tensorflow.NewCheckpointReader(file_name)
        if all_tensors:
            var_to_shape_map = reader.get_variable_to_shape_map()
            for key in var_to_shape_map:
                print("tensor_name: ", key)
                print(reader.get_tensor(key))
        elif not tensor_name:
            print(reader.debug_string().decode("utf-8"))
        else:
            print("tensor_name: ", tensor_name)
            print(reader.get_tensor(tensor_name))
    except Exception as e:  # pylint: disable=broad-except
        print(str(e))
        if "corrupted compressed block contents" in str(e):
            print("It's likely that your checkpoint file has been compressed "
                  "with SNAPPY.")


def parse_numpy_printoption(kv_str):
    """Sets a single numpy printoption from a string of the form 'x=y'.

    See documentation on numpy.set_printoptions() for details about what values
    x and y can take. x can be any option listed there other than 'formatter'.

    Args:
        kv_str: A string of the form 'x=y', such as 'threshold=100000'

    Raises:
        argparse.ArgumentTypeError: If the string couldn't be used to set any
                nump printoption.
    """
    k_v_str = kv_str.split("=", 1)
    if len(k_v_str) != 2 or not k_v_str[0]:
        raise argparse.ArgumentTypeError("'%s' is not in the form k=v." % kv_str)
    k, v_str = k_v_str
    printoptions = np.get_printoptions()
    if k not in printoptions:
        raise argparse.ArgumentTypeError("'%s' is not a valid printoption." % k)
    v_type = type(printoptions[k])
    if v_type is type(None):
        raise argparse.ArgumentTypeError(
                "Setting '%s' from the command line is not supported." % k)
    try:
        v = (v_type(v_str) if v_type is not bool
             else flags.BooleanParser().Parse(v_str))
    except ValueError as e:
        raise argparse.ArgumentTypeError(e.message)
    np.set_printoptions(**{k: v})


def main(unused_argv):
    if not FLAGS.file_name:
        print("Usage: inspect_checkpoint --file_name=checkpoint_file_name "
              "[--tensor_name=tensor_to_print]")
        sys.exit(1)
    else:
        print_tensors_in_checkpoint_file(FLAGS.file_name, FLAGS.tensor_name,
                                         FLAGS.all_tensors)


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.register("type", "bool", lambda v: v.lower() == "true")
    parser.add_argument(
            "--file_name", type=str, default="", help="Checkpoint filename. "
                                        "Note, if using Checkpoint V2 format, file_name is the "
                                        "shared prefix between all files in the checkpoint.")
    parser.add_argument(
            "--tensor_name",
            type=str,
            default="",
            help="Name of the tensor to inspect")
    parser.add_argument(
            "--all_tensors",
            nargs="?",
            const=True,
            type="bool",
            default=False,
            help="If True, print the values of all the tensors.")
    parser.add_argument(
            "--printoptions",
            nargs="*",
            type=parse_numpy_printoption,
            help="Argument for numpy.set_printoptions(), in the form 'k=v'.")
    FLAGS, unparsed = parser.parse_known_args()
    app.run(main=main, argv=[sys.argv[0]] + unparsed)