# Copyright (c) 2022-2025, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
#
# See LICENSE for license information.
"""JAX/TE base custom ops"""
import os
import re
from abc import ABCMeta, abstractmethod
from functools import partial
from packaging import version

from jax.extend import core
from jax.interpreters import xla, mlir
from jax.experimental.custom_partitioning import custom_partitioning
from jax._src.interpreters import batching
from jax._src import dispatch

import jax
import transformer_engine_jax

if version.parse(jax.__version__) >= version.parse("0.5.0"):
    from jax import ffi  # pylint: disable=ungrouped-imports
else:
    from jax.extend import ffi  # pylint: disable=ungrouped-imports


class BasePrimitive(metaclass=ABCMeta):
    """
    jax primitive
    """

    name = None

    @classmethod
    def enabled(cls):
        """
        A custom call is marked as disabled if the `cls.name` does not fully match the
        `NVTE_JAX_CUSTOM_CALLS_RE` pattern.
        By default, `NVTE_JAX_CUSTOM_CALLS_RE` is set to `.*`, which matches and enables all names.
        For example, set `NVTE_JAX_CUSTOM_CALLS_RE='^(?!te_act_lu$).+$'` to disable `te_act_lu`.
        """
        pattern = os.getenv("NVTE_JAX_CUSTOM_CALLS_RE", r".*")
        pattern = re.compile(pattern)
        is_enabled = pattern.fullmatch(cls.name) is not None
        return is_enabled

    @staticmethod
    @abstractmethod
    def abstract():
        """
        to describe computing graph
        """
        return NotImplemented

    @classmethod
    def outer_abstract(cls, *args, **kwargs):
        """
        optional abstract wrapper to eliminate workspace tensors
        """
        return cls.abstract(*args, **kwargs)

    @staticmethod
    @abstractmethod
    def lowering():
        """
        to describe MLIR
        """
        return NotImplemented

    @staticmethod
    @abstractmethod
    def impl():
        """
        to describe implementation
        """
        return NotImplemented

    @staticmethod
    @abstractmethod
    def batcher():
        """
        to describe batch rules for vmap
        """
        return NotImplemented

    @staticmethod
    @abstractmethod
    def infer_sharding_from_operands():
        """
        to describe infer_sharding_from_operands for custom_partitioning
        """
        return NotImplemented

    @staticmethod
    @abstractmethod
    def partition():
        """
        to describe partition for custom_partitioning
        """
        return NotImplemented

    @staticmethod
    @abstractmethod
    def shardy_sharding_rule(*args):
        """
        Returns the sharding rule for this primitive.
        """
        del args
        return "... -> ..."


def register_primitive(cls):
    """
    register jax primitive
    """

    def name_of_wrapper_p():
        return cls.name + "_wrapper"

    inner_p = core.Primitive(cls.name)
    dispatch.prim_requires_devices_during_lowering.add(inner_p)
    inner_p.multiple_results = cls.multiple_results
    inner_p.def_impl(partial(xla.apply_primitive, inner_p))
    inner_p.def_abstract_eval(cls.abstract)
    mlir.register_lowering(inner_p, cls.lowering, platform="cuda")
    cls.inner_primitive = inner_p

    outer_p = core.Primitive(name_of_wrapper_p())
    dispatch.prim_requires_devices_during_lowering.add(outer_p)
    outer_p.multiple_results = cls.multiple_results
    outer_p.def_impl(cls.impl)
    outer_p.def_abstract_eval(cls.outer_abstract)
    batching.primitive_batchers[outer_p] = cls.batcher
    outer_p_lower = custom_partitioning(cls.impl, static_argnums=cls.impl_static_args)
    outer_p_lower.def_partition(
        infer_sharding_from_operands=cls.infer_sharding_from_operands,
        partition=cls.partition,
        sharding_rule=cls.shardy_sharding_rule,
    )
    mlir.register_lowering(
        outer_p, mlir.lower_fun(outer_p_lower, multiple_results=cls.multiple_results)
    )
    cls.outer_primitive = outer_p


for _name, _value in transformer_engine_jax.registrations().items():
    ffi.register_ffi_target(_name, _value, platform="CUDA")
