#!/usr/bin/env python3
#
# Copyright (c) 2014 10X Genomics, Inc. All rights reserved.
#

"""Martian stage code API and common utility methods.

This module contains an API for python stage code to use to interact
with the higher-level martian logic, plus common utility methods.
"""

from __future__ import absolute_import, division, print_function

import json
import math
import os
import resource
import subprocess
import sys
from pathlib import PurePath


from typing import (  # pylint: disable=import-error, unused-import
    Any,
    Dict,
    NoReturn,
    Union,
)


# Singleton instance object.
if not "_INSTANCE" in globals():
    _INSTANCE = None


class StageException(Exception):
    """Base exception type for stage code."""


class Record:
    """An object with a set of attributes generated from a dictioanry."""

    def __init__(self, f_dict):
        # type: (Dict[str, Any]) -> None
        """Initializes the object from a dictionary."""
        self.slots = f_dict.keys()
        for field_name in self.slots:
            setattr(self, field_name, f_dict[field_name])

    def items(self):
        """Returns the a dictionary with the elements which were in the keys in
        dictionary used to initialize the record."""
        return {
            field_name: getattr(self, field_name) for field_name in self.slots
        }

    def __str__(self):
        """Formats the object as a string."""
        return str(self.items())

    def __iter__(self):
        """Iterate through the values of the object corresponding to keys in
        the dictionary used to initialize the object."""
        for field_name in self.slots:
            yield getattr(self, field_name)

    def __getitem__(self, index):
        # type: (int) -> Any
        """Get the value associated with the Nth key in the source
        dictionary."""
        return getattr(self, self.slots[index])

    def coerce_strings(self):
        """This exists only for backwards compatibility."""


def clear(outs):
    # type: (Record) -> None
    """Set all of the outs to None."""
    for field_name in outs.slots:
        setattr(outs, field_name, None)


def json_sanitize(data):
    """Converts NaN values into None values, and decode raw bytes."""
    retval = data
    if isinstance(data, float):
        # Handle exceptional floats.
        if math.isnan(data) or data == float("+Inf") or data == float("-Inf"):
            retval = None
    elif isinstance(data, dict):
        # Recurse on dictionaries.
        retval = {}
        for k in data.keys():
            retval[k] = json_sanitize(data[k])
    elif isinstance(data, str):
        # This branch is required to prevent the __iter__ branch from
        # processing strings.
        pass
    elif isinstance(data, bytes):
        retval = data.decode("utf-8", errors="ignore")
    elif isinstance(data, PurePath):
        retval = str(data)
    elif hasattr(data, "__iter__"):
        # Recurse on lists.
        retval = [json_sanitize(d) for d in data]
    return retval


def json_dumps_safe(data, indent=None):
    """Returns a formatted json string of the data, with NaN values converted
    to None."""
    return json.dumps(json_sanitize(data), indent=indent)


def get_mem_kb():
    # type: () -> int
    """Get the current max rss memory for this process and completed child
    processes."""
    return max(
        resource.getrusage(resource.RUSAGE_SELF).ru_maxrss,
        resource.getrusage(resource.RUSAGE_CHILDREN).ru_maxrss,
    )


def convert_gb_to_kb(mem_gb):
    # type: (float) -> float
    """Convert from gb to kb."""
    return mem_gb * 1024 * 1024


def padded_print(field_name, value):
    # type: (str, ...) -> str
    """Pad a string with leading spaces to be the same length as field_name."""
    offset = len(field_name) - len(str(value))
    if offset > 0:
        return (" " * offset) + str(value)
    return str(value)


def profile(func):
    """Add a function to the set of functions to be covered by the line profiler."""
    assert _INSTANCE is not None
    _INSTANCE.funcs.append(func)
    return func


# On linux, provide a method to set PDEATHSIG on child processes.
if sys.platform.startswith("linux"):
    import ctypes
    import ctypes.util
    from signal import SIGKILL

    _LIBC = ctypes.CDLL(ctypes.util.find_library("c"))

    _PR_SET_PDEATHSIG = ctypes.c_int(1)  # <sys/prctl.h>

    def child_preexec_set_pdeathsig():
        """When used as the preexec_fn argument for subprocess.Popen etc,
        causes the subprocess to receive SIGKILL if the parent process
        terminates."""
        zero = ctypes.c_ulong(0)
        _LIBC.prctl(
            _PR_SET_PDEATHSIG, ctypes.c_ulong(SIGKILL), zero, zero, zero
        )

else:
    child_preexec_set_pdeathsig = None  # pylint: disable=invalid-name


# pylint: disable=invalid-name,too-many-arguments
def Popen(
    args,
    bufsize=0,
    executable=None,
    stdin=None,
    stdout=None,
    stderr=None,
    preexec_fn=child_preexec_set_pdeathsig,
    close_fds=False,
    shell=False,
    cwd=None,
    env=None,
    universal_newlines=False,
    startupinfo=None,
    creationflags=0,
):
    # type: (...) -> subprocess.Popen
    """Log opening of a subprocess."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log("exec", " ".join(args))
    # pylint: disable=bad-option-value, subprocess-popen-preexec-fn, consider-using-with
    return subprocess.Popen(
        args,
        bufsize=bufsize,
        executable=executable,
        stdin=stdin,
        stdout=stdout,
        stderr=stderr,
        preexec_fn=preexec_fn,
        close_fds=close_fds,
        shell=shell,
        cwd=cwd,
        env=env,
        universal_newlines=universal_newlines,
        startupinfo=startupinfo,
        creationflags=creationflags,
    )


def check_call(args, stdin=None, stdout=None, stderr=None, shell=False):
    """Log running a given subprocess."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log("exec", " ".join(args))
    return subprocess.check_call(
        args,
        shell=shell,
        stdin=stdin,
        stdout=stdout,
        stderr=stderr,
        preexec_fn=child_preexec_set_pdeathsig,
    )


def make_path(filename):
    # type: (Union[str, bytes]) -> bytes
    """Get the file path for a named file."""
    if isinstance(filename, str):
        filename = filename.encode("utf-8")
    assert _INSTANCE is not None
    return os.path.join(_INSTANCE.metadata.files_path, filename)


def get_invocation_args():
    # type: () -> Dict[str, Any]
    """Get the args from the invocation."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.invocation["args"]


def get_invocation_call():
    # type: () -> str
    """Get the call information from the invocation."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.invocation["call"]


def get_martian_version():
    # type: () -> str
    """Get the martian version from the jobinfo."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.version["martian"]


def get_pipelines_version():
    # type: () -> str
    """Get the pipelines version from the jobinfo."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.version["pipelines"]


def get_threads_allocation():
    # type: () -> float
    """Get the number of threads allocated to this job by the runtime."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.threads


def get_memory_allocation():
    # type: () -> float
    """Get the amount of memory in GB allocated to this job by the runtime."""
    assert _INSTANCE is not None
    assert _INSTANCE.jobinfo is not None
    return _INSTANCE.jobinfo.mem_gb


def get_pipestance_uuid():
    # type: () -> str
    """Get the UUID of the top-level pipeline instance.

    Returns an empty string if the UUID is not available.
    """
    return os.getenv("MRO_UUID") or os.getenv("MRO_FORCE_UUID") or ""


def update_progress(message):
    # type: (Union[str, bytes]) -> None
    """Updates the current progress of the stage, which will be displayed to
    the user (in the mrp log) next time mrp reads the file."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.progress(message)


def log_info(message):
    # type: (Union[str, bytes]) -> None
    """Log a message."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log("info", message)


def log_warn(message):
    # type: (Union[str, bytes]) -> None
    """Log a warning."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log("warn", message)


def log_time(message):
    # type: (Union[str, bytes]) -> None
    """Log a timestamp for an action."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log("time", message)


def log_json(label, obj):
    # type: (Union[str, bytes], Any) -> None
    """Log an object in json format."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.log(
        "json", json_dumps_safe({"label": label, "object": obj})
    )


def throw(message):
    # type: (object) -> NoReturn
    """Raise a stage exception."""
    raise StageException(message)


def exit(message):  # pylint: disable=redefined-builtin
    # type: (Union[str, bytes]) -> NoReturn
    """Fail the pipeline with an assertion."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.write_assert(message)
    _INSTANCE.done()


def alarm(message):
    # type: (Union[str, bytes]) -> None
    """Add a message to the alarms."""
    assert _INSTANCE is not None
    _INSTANCE.metadata.alarm(message)


#################################################
# Initialization                                #
#################################################


def test_initialize(path):
    # type: (Union[str, bytes]) -> Any
    """Initialize with a fake test metadata."""
    # pylint: disable=bad-option-value, import-outside-toplevel
    import martian_shell as mr_shell

    # pylint: disable=global-statement
    global _INSTANCE
    _INSTANCE = mr_shell.StageWrapper(
        [None, None, "main", path, path, ""], True
    )
    return _INSTANCE