#!/usr/bin/env python3
# Copyright (c) Microsoft Corporation.
# SPDX-License-Identifier: Apache-2.0

# DeepSpeed Team

from __future__ import annotations
'''Copyright The Microsoft DeepSpeed Team'''
"""
Checks each file in sys.argv for the string "torch.cuda".
Modified from https://github.com/jlebar/pre-commit-hooks/blob/master/check_do_not_submit.py
"""

import subprocess
import sys


def err(s: str) -> None:
    print(s, file=sys.stderr)


# There are many ways we could search for the string "torch.cuda", but `git
# grep --no-index` is nice because
#  - it's very fast (as compared to iterating over the file in Python)
#  - we can reasonably assume it's available on all machines
#  - unlike plain grep, which is slower and has different flags on MacOS versus
#    Linux, git grep is always the same.
res = subprocess.run(
    ["git", "grep", "-Hn", "--no-index", "-e", r"torch\.cuda", "--and", "--not", "-e", "#ignore-cuda", *sys.argv[1:]],
    capture_output=True,
)
if res.returncode == 0:
    err('Error: The string "torch.cuda" was found.\nPlease replace all calls to torch.cuda with "get_accelerator()" and add the following import line:\n\n    from deepspeed.accelerator import get_accelerator\n\nIf your code is mean to be cuda specific, please add the following comment in the line with torch.cuda:\n\n    #ignore-cuda\n'
        )
    err(res.stdout.decode("utf-8"))
    sys.exit(1)
elif res.returncode == 2:
    err(f"Error invoking grep on {', '.join(sys.argv[1:])}:")
    err(res.stderr.decode("utf-8"))
    sys.exit(2)

res = subprocess.run(
    ["git", "grep", "-Hn", "--no-index", r"\.cuda()", *sys.argv[1:]],
    capture_output=True,
)
if res.returncode == 0:
    err('Error: The string ".cuda()" was found. This implies convert a tensor to cuda tensor.  Please replace all calls to tensor.cuda() with "tensor.to(get_accelerator().device_name())" and add the following import line:\nfrom deepspeed.accelerator import get_accelerator'
        )
    err(res.stdout.decode("utf-8"))
    sys.exit(1)
elif res.returncode == 2:
    err(f"Error invoking grep on {', '.join(sys.argv[1:])}:")
    err(res.stderr.decode("utf-8"))
    sys.exit(2)

files = []
for file in sys.argv[1:]:
    if not file.endswith(".cpp"):
        files.append(file)

res = subprocess.run(
    ["git", "grep", "-Hn", "--no-index", r"\.is_cuda", *files],
    capture_output=True,
)
if res.returncode == 0:
    err('''
Error: The string ".is_cuda" was found. This implies checking if a tensor is a cuda tensor.
       Please replace all calls to "tensor.is_cuda" with "get_accelerator().on_accelerator(tensor)",
       and add the following import line:
       'from deepspeed.accelerator import get_accelerator'
''')
    err(res.stdout.decode("utf-8"))
    sys.exit(1)
elif res.returncode == 2:
    err(f"Error invoking grep on {', '.join(files)}:")
    err(res.stderr.decode("utf-8"))
    sys.exit(2)