# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project

import pytest
import torch

from vllm._aiter_ops import rocm_aiter_ops
from vllm.config import CompilationConfig, VllmConfig, set_current_vllm_config
from vllm.model_executor.custom_op import CustomOp
from vllm.model_executor.layers.activation import (
    GeluAndMul,
    ReLUSquaredActivation,
    SiluAndMul,
)
from vllm.model_executor.layers.fused_moe.fused_moe import (
    dispatch_topk_func,
    vllm_topk_softmax,
)
from vllm.model_executor.layers.layernorm import (
    RMSNorm,
    dispatch_rocm_rmsnorm_func,
    fused_add_rms_norm,
    rms_norm,
)
from vllm.platforms import current_platform

RMS_NORM_SUPPORTED_DTYPES = [torch.float16, torch.bfloat16]


# Registered subclass for test
@CustomOp.register("relu3")
class Relu3(ReLUSquaredActivation):
    pass


@pytest.mark.parametrize(
    "env, compilation_mode, backend, ops_enabled, default_on",
    [
        # Default values based on compile level
        # - All by default (no Inductor compilation)
        (None, 0, "eager", [True] * 4, True),
        (None, 1, "eager", [True] * 4, True),
        (None, 2, "eager", [True] * 4, True),
        (None, 3, "eager", [True] * 4, True),
        # - None by default (with Inductor)
        (None, 0, "inductor", [True] * 4, True),
        # - None by default (with Inductor)
        (None, 1, "inductor", [False] * 4, False),
        (None, 2, "inductor", [False] * 4, False),
        (None, 3, "inductor", [False] * 4, False),
        # Explicitly enabling/disabling
        #
        # Default: all
        #
        # All but SiluAndMul
        ("+rms_norm,-silu_and_mul", 0, "inductor", [1, 0, 1, 1], True),
        # Only ReLU3
        ("none,-rms_norm,+relu3", 1, "eager", [0, 0, 0, 1], False),
        # All but SiluAndMul
        ("all,-silu_and_mul", 2, "inductor", [1, 0, 1, 1], True),
        # All but ReLU3 (even if ReLU2 is on)
        ("-relu3,+relu2", 3, "eager", [1, 1, 1, 0], True),
        # RMSNorm and SiluAndMul
        ("none,-relu3,+rms_norm,+silu_and_mul", 3, "eager", [1, 1, 0, 0], False),
        # All but RMSNorm
        ("-rms_norm", 3, "eager", [0, 1, 1, 1], True),
        #
        # Default: none
        #
        # Only ReLU3
        ("none,+relu3", 3, "inductor", [0, 0, 0, 1], False),
        # All but RMSNorm
        ("all,-rms_norm", 3, "inductor", [0, 1, 1, 1], True),
    ],
)
def test_enabled_ops(
    env: str | None,
    compilation_mode: int,
    backend: str,
    ops_enabled: list[int],
    default_on: bool,
):
    custom_ops = env.split(",") if env else []
    vllm_config = VllmConfig(
        compilation_config=CompilationConfig(
            backend=backend, mode=compilation_mode, custom_ops=custom_ops
        )
    )
    with set_current_vllm_config(vllm_config):
        assert CustomOp.default_on() == default_on

        ops_enabled = [bool(x) for x in ops_enabled]

        assert RMSNorm(1024).enabled() == ops_enabled[0]
        assert CustomOp.op_registry["rms_norm"].enabled() == ops_enabled[0]

        assert SiluAndMul().enabled() == ops_enabled[1]
        assert CustomOp.op_registry["silu_and_mul"].enabled() == ops_enabled[1]

        assert GeluAndMul().enabled() == ops_enabled[2]
        assert CustomOp.op_registry["gelu_and_mul"].enabled() == ops_enabled[2]

        # If registered, subclasses should follow their own name
        assert Relu3().enabled() == ops_enabled[3]
        assert CustomOp.op_registry["relu3"].enabled() == ops_enabled[3]

        # Unregistered subclass
        class SiluAndMul2(SiluAndMul):
            pass

        # Subclasses should not require registration
        assert SiluAndMul2().enabled() == SiluAndMul().enabled()


@pytest.mark.parametrize(
    "env", ["all,none", "all,+rms_norm,all", "+rms_norm,-rms_norm"]
)
def test_enabled_ops_invalid(env: str):
    with pytest.raises(Exception):  # noqa
        vllm_config = VllmConfig(
            compilation_config=CompilationConfig(custom_ops=env.split(","))
        )
        with set_current_vllm_config(vllm_config):
            RMSNorm(1024).enabled()


@pytest.mark.parametrize(
    "use_rocm_aiter", [True, False] if current_platform.is_rocm() else [False]
)
def test_topk_dispatch(use_rocm_aiter: bool):
    topk_func = dispatch_topk_func(use_rocm_aiter)

    if current_platform.is_rocm() and use_rocm_aiter:
        assert topk_func == rocm_aiter_ops.topk_softmax
    else:
        assert topk_func == vllm_topk_softmax


@pytest.mark.parametrize("add_residual", [True, False])
@pytest.mark.parametrize("dtype", [torch.float32, torch.float16, torch.bfloat16])
@pytest.mark.parametrize("use_rocm_aiter", [True, False])
@pytest.mark.skipif(
    not current_platform.is_rocm(), reason="AITER is a feature exclusive for ROCm"
)
def test_rms_norm_dispatch(
    add_residual: bool, dtype: torch.dtype, use_rocm_aiter: bool
):
    rms_norm_func = dispatch_rocm_rmsnorm_func(add_residual, dtype, use_rocm_aiter)

    should_use_rocm_aiter = (
        current_platform.is_rocm()
        and use_rocm_aiter
        and dtype in RMS_NORM_SUPPORTED_DTYPES
    )

    if add_residual and should_use_rocm_aiter:
        assert rms_norm_func == rocm_aiter_ops.rms_norm2d_with_add
    elif should_use_rocm_aiter:
        assert rms_norm_func == rocm_aiter_ops.rms_norm
    elif add_residual:
        assert rms_norm_func == fused_add_rms_norm
    else:
        assert rms_norm_func == rms_norm