# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""Tests for the MOE layers.

Run `pytest tests/kernels/test_moe.py`.
"""

import functools
import importlib
import sys
from collections.abc import Callable
from dataclasses import dataclass
from typing import Any

import pytest
import torch
from torch.nn import Parameter
from torch.nn import functional as F
from transformers import MixtralConfig
from transformers.models.mixtral.modeling_mixtral import MixtralSparseMoeBlock

import vllm.model_executor.layers.fused_moe  # noqa
from tests.kernels.moe.utils import fused_moe
from tests.kernels.utils import opcheck, stack_and_dev, torch_experts, torch_moe
from vllm._aiter_ops import rocm_aiter_ops
from vllm.config import VllmConfig, set_current_vllm_config
from vllm.distributed.parallel_state import init_distributed_environment
from vllm.forward_context import set_forward_context
from vllm.model_executor.layers.fused_moe.config import (
    FUSED_MOE_UNQUANTIZED_CONFIG,
    int4_w4a16_moe_quant_config,
    int8_w8a16_moe_quant_config,
)
from vllm.model_executor.layers.fused_moe.fused_marlin_moe import (
    batched_fused_marlin_moe,
    fused_marlin_moe,
)
from vllm.model_executor.layers.fused_moe.fused_moe import (
    fused_topk,
    modular_triton_fused_moe,
)
from vllm.model_executor.layers.fused_moe.moe_torch_iterative import (
    fused_moe as iterative_moe,
)
from vllm.model_executor.layers.quantization.utils.marlin_utils import (
    marlin_permute_bias,
)
from vllm.model_executor.layers.quantization.utils.marlin_utils_fp4 import (
    rand_marlin_weight_mxfp4_like,
    rand_marlin_weight_nvfp4_like,
)
from vllm.model_executor.layers.quantization.utils.marlin_utils_fp8 import (
    marlin_quant_fp8_torch,
)
from vllm.model_executor.layers.quantization.utils.marlin_utils_test import (
    awq_marlin_quantize,
    marlin_quantize,
)
from vllm.model_executor.layers.quantization.utils.quant_utils import quantize_weights
from vllm.model_executor.models.mixtral import MixtralMoE
from vllm.platforms import current_platform
from vllm.scalar_type import ScalarType, scalar_types

NUM_EXPERTS = [8, 64, 192]
EP_SIZE = [1, 4]
TOP_KS = [2, 6]

MOE_MARLIN_QUANT_TEST_CONFIGS = [
    # AWQ-INT4
    {"b_type": scalar_types.uint4, "group_blocks": [-1, 2, 4, 8]},
    # GPTQ-INT4
    {
        "b_type": scalar_types.uint4b8,
        "support_act_order": True,
        "group_blocks": [-1, 2, 4, 8],
    },
    # GPTQ-INT8
    {
        "b_type": scalar_types.uint8b128,
        "support_act_order": True,
        "group_blocks": [-1, 2, 4, 8],
    },
    # FP8
    {"b_type": scalar_types.float8_e4m3fn, "group_blocks": [-1, 8]},
    # NVFP4
    {"b_type": scalar_types.float4_e2m1f, "group_blocks": [1]},
    # MXFP4
    {
        "a_type": [scalar_types.bfloat16],
        "b_type": scalar_types.float4_e2m1f,
        "group_blocks": [2],
    },
    # AWQ-INT4 with INT8 activation
    {
        "a_type": [scalar_types.int8],
        "b_type": scalar_types.uint4,
        "group_blocks": [-1, 2, 4, 8],
    },
    # GPTQ-INT4 with INT8 activation
    {
        "a_type": [scalar_types.int8],
        "b_type": scalar_types.uint4b8,
        "group_blocks": [-1, 2, 4, 8],
    },
    # GPTQ-INT4 with FP8 activation
    {
        "a_type": [scalar_types.float8_e4m3fn],
        "b_type": scalar_types.uint4b8,
        "group_blocks": [-1, 2, 4, 8],
    },
    # AWQ-INT4 with FP8 activation
    {
        "a_type": [scalar_types.float8_e4m3fn],
        "b_type": scalar_types.uint4,
        "group_blocks": [-1, 2, 4, 8],
    },
    # MXFP4 with FP8 activation
    {
        "a_type": [scalar_types.float8_e4m3fn],
        "b_type": scalar_types.float4_e2m1f,
        "c_type": [scalar_types.bfloat16],
        "group_blocks": [2],
    },
]

FUSED_MOE_MNK_FACTORS = [
    (1, 128, 128),
    (1, 2048, 128),
    (33, 2048, 128),
    (32768, 2048, 511),
    (40000, 1024, 1024),
]

FUSED_MOE_WN16_MNK_FACTORS = [
    (1, 128, 128),
    (1, 1024, 1024),
    (32, 2048, 128),
    (222, 2048, 1024),
]

vllm_config = VllmConfig()


def run_moe_test(
    baseline: Callable | torch.Tensor,
    moe_fn: Callable,
    a: torch.Tensor,
    w1: torch.Tensor,
    w2: torch.Tensor,
    score: torch.Tensor,
    topk: int,
    global_num_experts: int = -1,
    expert_map: torch.Tensor | None = None,
    padding: bool = False,
    use_compile: bool = False,
    use_cudagraph: bool = False,
    atol: float = 2e-2,
    rtol: float = 0,
) -> torch.Tensor:
    if isinstance(baseline, torch.Tensor):
        baseline_output = baseline
    else:
        baseline_output = baseline(
            a,
            w1,
            w2,
            score,
            topk,
            global_num_experts=global_num_experts,
            expert_map=expert_map,
        )

    # Pad the weight if moe padding is enabled
    if padding:
        w1 = F.pad(w1, (0, 128), "constant", 0)[..., 0:-128]
        w2 = F.pad(w2, (0, 128), "constant", 0)[..., 0:-128]

    if use_compile:
        moe_fn = torch.compile(moe_fn, backend="inductor", fullgraph=True)
        torch._dynamo.mark_dynamic(a, 0)
        torch._dynamo.mark_dynamic(score, 0)

    test_output = moe_fn(
        a,
        w1,
        w2,
        score,
        topk,
        global_num_experts=global_num_experts,
        expert_map=expert_map,
    )

    if use_cudagraph:
        test_output.fill_(0)
        stream = torch.cuda.Stream()
        graph = torch.cuda.CUDAGraph()
        with torch.cuda.graph(graph, stream=stream):
            test_output = moe_fn(
                a,
                w1,
                w2,
                score,
                topk,
                global_num_experts=global_num_experts,
                expert_map=expert_map,
            )
        torch.cuda.synchronize()
        graph.replay()
        torch.cuda.synchronize()

    torch.testing.assert_close(test_output, baseline_output, atol=atol, rtol=rtol)

    return baseline_output


@pytest.mark.parametrize("m,n,k", FUSED_MOE_MNK_FACTORS)
@pytest.mark.parametrize("e", NUM_EXPERTS)
@pytest.mark.parametrize("topk", TOP_KS)
@pytest.mark.parametrize("ep_size", EP_SIZE)
@pytest.mark.parametrize("dtype", [torch.bfloat16])
@pytest.mark.parametrize("padding", [True, False])
@pytest.mark.parametrize("chunk_size", [8192])
def test_fused_moe(
    m: int,
    n: int,
    k: int,
    e: int,
    topk: int,
    ep_size: int,
    dtype: torch.dtype,
    padding: bool,
    chunk_size: int,
    monkeypatch,
):
    current_platform.seed_everything(7)

    monkeypatch.setenv("VLLM_FUSED_MOE_CHUNK_SIZE", str(chunk_size))

    #
    # Setup test data
    #

    #
    # Setup test data
    #

    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10

    score = torch.randn((m, e), device="cuda", dtype=dtype)

    if ep_size > 1:
        local_e = e // ep_size
        e_ids = torch.randint(0, e, (local_e,), device="cuda", dtype=torch.int32)
        e_map = torch.full((e,), -1, device="cuda", dtype=torch.int32)
        e_map[e_ids] = torch.arange(local_e, device="cuda", dtype=torch.int32)
        w1 = w1[e_ids]
        w2 = w2[e_ids]
    else:
        e_map = None

    #
    # Setup test functions
    #
    quant_config = FUSED_MOE_UNQUANTIZED_CONFIG

    m_fused_moe_fn = modular_triton_fused_moe(quant_config)

    def m_fused_moe(
        a: torch.Tensor,
        w1: torch.Tensor,
        w2: torch.Tensor,
        score: torch.Tensor,
        topk: int,
        global_num_experts: int = -1,
        expert_map: torch.Tensor | None = None,
    ) -> torch.Tensor:
        topk_weights, topk_ids, _ = fused_topk(a, score, topk, False)
        return m_fused_moe_fn(
            a,
            w1,
            w2,
            topk_weights,
            topk_ids,
            global_num_experts=global_num_experts,
            expert_map=expert_map,
        )

    fused_moe_fn = functools.partial(fused_moe, renormalize=False)

    #
    # Run tests
    #
    runner = functools.partial(
        run_moe_test,
        a=a,
        w1=w1,
        w2=w2,
        score=score,
        topk=topk,
        global_num_experts=e,
        expert_map=e_map,
        padding=padding,
    )

    # Note: for now use_compile will error out if the problem size is
    # large enough to trigger chunking. I'm leaving the flag and
    # setup code in case we are able to revisit this later.
    use_compile = False

    use_cudagraph = n >= 1024 and k >= 1024 and current_platform.is_cuda_alike()

    with set_current_vllm_config(vllm_config):
        baseline_output = runner(torch_moe, iterative_moe)
        runner(
            baseline_output,
            fused_moe_fn,
            use_compile=use_compile,
            use_cudagraph=use_cudagraph,
        )
        runner(
            baseline_output,
            m_fused_moe,
            use_compile=use_compile,
            use_cudagraph=use_cudagraph,
        )


@pytest.mark.parametrize("m,n,k", FUSED_MOE_WN16_MNK_FACTORS)
@pytest.mark.parametrize("e", NUM_EXPERTS)
@pytest.mark.parametrize("topk", TOP_KS)
@pytest.mark.parametrize("ep_size", EP_SIZE)
@pytest.mark.parametrize("dtype", [torch.bfloat16])
@pytest.mark.parametrize("group_size", [64, 128])
@pytest.mark.parametrize("has_zp", [True, False])
@pytest.mark.parametrize("weight_bits", [4, 8])
def test_fused_moe_wn16(
    m: int,
    n: int,
    k: int,
    e: int,
    topk: int,
    ep_size: int,
    dtype: torch.dtype,
    group_size: int,
    has_zp: bool,
    weight_bits: int,
):
    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10
    score = torch.randn((m, e), device="cuda", dtype=dtype)

    if weight_bits == 4:
        pack_factor = 2
        quant_type = scalar_types.uint4 if has_zp else scalar_types.uint4b8
    elif weight_bits == 8:
        pack_factor = 1
        quant_type = scalar_types.uint8 if has_zp else scalar_types.uint8b128

    w1_ref = w1.clone()
    w2_ref = w2.clone()
    w1_qweight = torch.empty(
        (e, 2 * n, k // pack_factor), device="cuda", dtype=torch.uint8
    )
    w2_qweight = torch.empty((e, k, n // pack_factor), device="cuda", dtype=torch.uint8)
    w1_scales = torch.empty((e, 2 * n, k // group_size), device="cuda", dtype=dtype)
    w2_scales = torch.empty((e, k, n // group_size), device="cuda", dtype=dtype)
    w1_qzeros = torch.empty(
        (e, 2 * n // pack_factor, k // group_size), device="cuda", dtype=torch.uint8
    )
    w2_qzeros = torch.empty(
        (e, k // pack_factor, n // group_size), device="cuda", dtype=torch.uint8
    )

    for i in range(e * 2):
        expert_id = i % e
        if i // e == 0:
            w, w_ref, w_qweight, w_scales, w_qzeros = (
                w1,
                w1_ref,
                w1_qweight,
                w1_scales,
                w1_qzeros,
            )
        else:
            w, w_ref, w_qweight, w_scales, w_qzeros = (
                w2,
                w2_ref,
                w2_qweight,
                w2_scales,
                w2_qzeros,
            )
        weight, qweight, scales, qzeros = quantize_weights(
            w[expert_id].T, quant_type, group_size, has_zp, False
        )
        weight = weight.T
        qweight = qweight.T.contiguous().to(torch.uint8)
        scales = scales.T
        if has_zp:
            qzeros = qzeros.T.contiguous().to(torch.uint8)
        if weight_bits == 4:
            qweight = qweight[:, 1::2] * 16 + qweight[:, ::2]
            if has_zp:
                qzeros = qzeros[1::2, :] * 16 + qzeros[::2, :]

        w_ref[expert_id] = weight
        w_qweight[expert_id] = qweight
        w_scales[expert_id] = scales
        if has_zp:
            w_qzeros[expert_id] = qzeros

    if ep_size > 1:
        local_e = e // ep_size
        e_ids = torch.randint(0, e, (local_e,), device="cuda", dtype=torch.int32)
        e_map = torch.full((e,), -1, device="cuda", dtype=torch.int32)
        e_map[e_ids] = torch.arange(local_e, device="cuda", dtype=torch.int32)
        w1_ref = w1_ref[e_ids]
        w2_ref = w2_ref[e_ids]
        w1_qweight = w1_qweight[e_ids]
        w2_qweight = w2_qweight[e_ids]
        w1_scales = w1_scales[e_ids]
        w2_scales = w2_scales[e_ids]
        w1_qzeros = w1_qzeros[e_ids]
        w2_qzeros = w2_qzeros[e_ids]
    else:
        e_map = None

    if weight_bits == 4:
        quant_config_builder = int4_w4a16_moe_quant_config
    else:
        assert weight_bits == 8
        quant_config_builder = int8_w8a16_moe_quant_config

    quant_config = quant_config_builder(
        w1_scale=w1_scales,
        w2_scale=w2_scales,
        w1_zp=w1_qzeros if has_zp else None,
        w2_zp=w2_qzeros if has_zp else None,
        block_shape=[0, group_size],
    )

    with set_current_vllm_config(vllm_config):
        triton_output = fused_moe(
            a,
            w1_qweight,
            w2_qweight,
            score,
            topk,
            renormalize=False,
            global_num_experts=e,
            expert_map=e_map,
            quant_config=quant_config,
        )
        torch_output = torch_moe(a, w1_ref, w2_ref, score, topk, expert_map=e_map)

    torch.testing.assert_close(triton_output, torch_output, atol=2e-2, rtol=0)


@pytest.mark.parametrize("dtype", [torch.bfloat16])
@pytest.mark.parametrize("padding", [True, False])
@pytest.mark.parametrize(
    "use_rocm_aiter", [True, False] if current_platform.is_rocm() else [False]
)
@torch.inference_mode()
def test_mixtral_moe(
    dist_init, dtype: torch.dtype, padding: bool, use_rocm_aiter: bool, monkeypatch
):
    """Make sure our Mixtral MoE implementation agrees with the one from
    huggingface."""

    # clear the cache before every test
    # Force reload aiter_ops to pick up the new environment variables.
    if "rocm_aiter_ops" in sys.modules:
        importlib.reload(rocm_aiter_ops)

    if use_rocm_aiter:
        monkeypatch.setenv("VLLM_ROCM_USE_AITER", "1")
        if dtype == torch.float32:
            pytest.skip("AITER ROCm test skip for float32")

    monkeypatch.setenv("RANK", "0")
    monkeypatch.setenv("LOCAL_RANK", "0")
    monkeypatch.setenv("WORLD_SIZE", "1")
    monkeypatch.setenv("MASTER_ADDR", "localhost")
    monkeypatch.setenv("MASTER_PORT", "12345")
    init_distributed_environment()

    # Instantiate our and huggingface's MoE blocks
    vllm_config.compilation_config.static_forward_context = dict()
    with set_current_vllm_config(vllm_config), set_forward_context(None, vllm_config):
        config = MixtralConfig()
        hf_moe = MixtralSparseMoeBlock(config).to(dtype).to("cuda")
        vllm_moe = MixtralMoE(
            num_experts=config.num_local_experts,
            top_k=config.num_experts_per_tok,
            hidden_size=config.hidden_size,
            intermediate_size=config.intermediate_size,
            params_dtype=dtype,
            tp_size=1,
            dp_size=1,
        ).cuda()

        # Load the weights
        vllm_moe.gate.weight.data[:] = hf_moe.gate.weight.data
        for i in range(config.num_local_experts):
            weights = (
                hf_moe.experts[i].w1.weight.data,
                hf_moe.experts[i].w3.weight.data,
            )
            vllm_moe.experts.w13_weight[i][:] = torch.cat(weights, dim=0)
            vllm_moe.experts.w2_weight[i][:] = hf_moe.experts[i].w2.weight.data

        # Generate input batch of dimensions [batch_size, seq_len, hidden_dim]
        hf_inputs = torch.randn((1, 64, config.hidden_size)).to(dtype).to("cuda")
        # vLLM uses 1D query [num_tokens, hidden_dim]
        vllm_inputs = hf_inputs.flatten(0, 1)

        # Pad the weight if moe padding is enabled
        if padding:
            vllm_moe.experts.w13_weight = Parameter(
                F.pad(vllm_moe.experts.w13_weight, (0, 128), "constant", 0)[
                    ..., 0:-128
                ],
                requires_grad=False,
            )
            vllm_moe.experts.w2_weight = Parameter(
                F.pad(vllm_moe.experts.w2_weight, (0, 128), "constant", 0)[..., 0:-128],
                requires_grad=False,
            )
            torch.cuda.synchronize()
            torch.cuda.empty_cache()

        # Run forward passes for both MoE blocks
        hf_states, _ = hf_moe.forward(hf_inputs)
        vllm_states = vllm_moe.forward(vllm_inputs)

    mixtral_moe_tol = {
        torch.float32: 1e-3,
        torch.float16: 1e-3,
        torch.bfloat16: 1e-2,
    }

    if use_rocm_aiter:
        # The values of rtol and atol are set based on the tests in ROCM AITER package.
        # https://github.com/ROCm/aiter/blob/dfed377f4be7da96ca2d75ac0761f569676f7240/op_tests/test_moe.py#L174
        torch.testing.assert_close(
            hf_states.flatten(0, 1), vllm_states, rtol=0.01, atol=100
        )
    else:
        torch.testing.assert_close(
            hf_states.flatten(0, 1),
            vllm_states,
            rtol=mixtral_moe_tol[dtype],
            atol=mixtral_moe_tol[dtype],
        )


def marlin_moe_generate_valid_test_cases():
    import itertools

    m_list = [1, 123, 666]
    n_list = [128, 1024]
    k_list = [256, 2048]
    e_list = [5, 12]
    topk_list = [2, 3]
    ep_size_list = [1, 4]
    act_order_list = [True, False]
    is_k_full_list = [True, False]

    all_combinations = itertools.product(
        MOE_MARLIN_QUANT_TEST_CONFIGS,
        m_list,
        n_list,
        k_list,
        e_list,
        topk_list,
        ep_size_list,
        act_order_list,
        is_k_full_list,
    )

    def is_invalid(
        a_type,
        b_type,
        c_type,
        group_blocks,
        m,
        n,
        k,
        e,
        topk,
        ep_size,
        act_order,
        is_k_full,
    ):
        group_size = group_blocks if group_blocks <= 0 else group_blocks * 16
        if group_size > 0 and k % group_size != 0:
            return False

        if act_order and group_size in [-1, k, n]:
            return False
        if group_size in [k, n]:
            return False
        if not act_order and is_k_full:
            return False

        return a_type.size_bits < 16 or a_type is c_type

    cases = []
    for case in all_combinations:
        quant_test_config, m, n, k, _, _, _, act_order, *_ = case
        if act_order and not quant_test_config.get("support_act_order", False):
            continue

        f16_types = [scalar_types.float16]
        inner_combinations = itertools.product(
            quant_test_config.get("a_type", f16_types),
            [quant_test_config["b_type"]],
            quant_test_config.get("c_type", f16_types),
            quant_test_config["group_blocks"],
        )

        for sub_case in inner_combinations:
            if (
                sub_case[0] == scalar_types.float8_e4m3fn
                and current_platform.get_device_capability() not in [89, 120]
            ):
                continue
            args = sub_case + (m, n, k) + case[4:]
            if is_invalid(*args):
                cases.append(args)
    return cases


@dataclass
class MarlinMoEWeightData:
    w_ref: torch.Tensor
    qweight: torch.Tensor
    scales: torch.Tensor
    global_scale: torch.Tensor | None
    a_scales_factor: torch.Tensor | None
    g_idx: torch.Tensor | None
    zeros: torch.Tensor | None
    sort_indices: torch.Tensor | None
    marlin_bias: torch.Tensor | None

    @staticmethod
    def make(
        w: torch.Tensor,
        quant_type: ScalarType,
        group_size: int,
        act_order: bool | None = None,
        bias: torch.Tensor | None = None,
        input_type: ScalarType = None,
    ) -> "MarlinMoEWeightData":
        assert w.ndim == 3

        has_zp = quant_type in [scalar_types.uint4, scalar_types.uint8]
        k = w.shape[-1]

        if input_type == scalar_types.int8:
            input_dtype = torch.int8
        elif input_type == scalar_types.float8_e4m3fn:
            input_dtype = torch.float8_e4m3fn
        else:
            input_dtype = w.dtype

        w_ref_l: list[torch.Tensor] = []
        qweight_l: list[torch.Tensor] = []
        scales_l: list[torch.Tensor] = []
        global_scale_l: list[torch.Tensor] = []
        zeros_l: list[torch.Tensor] = []
        g_idx_l: list[torch.Tensor] = []
        sort_indices_l: list[torch.Tensor] = []
        bias_l: list[torch.Tensor] = []

        for i in range(w.shape[0]):
            if quant_type == scalar_types.float4_e2m1f:
                if group_size == 16:
                    w_ref, qweight, scales, global_scale = (
                        rand_marlin_weight_nvfp4_like(
                            w[i], group_size, input_dtype=input_dtype
                        )
                    )
                else:
                    w_ref, qweight, scales = rand_marlin_weight_mxfp4_like(
                        w[i], group_size, input_dtype=input_dtype
                    )
                    global_scale = None

                w_ref_l.append(w_ref.T)
                qweight_l.append(qweight)
                scales_l.append(scales)
                if global_scale is not None:
                    global_scale_l.append(global_scale)
            elif quant_type == scalar_types.float8_e4m3fn:
                w_ref, qweight, scales = marlin_quant_fp8_torch(
                    w[i], group_size, input_dtype=input_dtype
                )
                w_ref_l.append(w_ref.T)
                qweight_l.append(qweight)
                scales_l.append(scales)
            elif has_zp:
                w_ref, qweight, scales, zeros = awq_marlin_quantize(
                    w[i].transpose(1, 0),
                    quant_type,
                    group_size,
                    input_dtype=input_dtype,
                )

                w_ref_l.append(w_ref.T)
                qweight_l.append(qweight)
                scales_l.append(scales)
                zeros_l.append(zeros)
            else:
                test_perm = torch.randperm(k)
                w_ref, qweight, scales, g_idx, sort_indices, _ = marlin_quantize(
                    w[i].transpose(1, 0),
                    quant_type,
                    group_size,
                    act_order,
                    test_perm,
                    input_dtype=input_dtype,
                )

                w_ref_l.append(w_ref.T)
                qweight_l.append(qweight)
                scales_l.append(scales)
                g_idx_l.append(g_idx)
                sort_indices_l.append(sort_indices)

            if bias is not None:
                bias_l.append(marlin_permute_bias(bias[i]))

        w_ref = stack_and_dev(w_ref_l)
        qweight = stack_and_dev(qweight_l).contiguous()
        scales = stack_and_dev(scales_l)
        global_scale = stack_and_dev(global_scale_l) if global_scale_l else None
        g_idx = stack_and_dev(g_idx_l) if g_idx_l else None
        zeros = stack_and_dev(zeros_l) if zeros_l else None
        sort_indices = stack_and_dev(sort_indices_l) if sort_indices_l else None
        marlin_bias = stack_and_dev(bias_l) if bias_l else None

        a_scales_factor = None
        if input_type == scalar_types.int8 and group_size != -1:
            a_scales_factor = 1 / 4096 * scales.max().float()
            scales = scales / scales.max() * 4096
            scales = scales.round().to(torch.int16).view(w.dtype)

        return MarlinMoEWeightData(
            w_ref=w_ref,
            qweight=qweight,
            scales=scales,
            global_scale=global_scale,
            a_scales_factor=a_scales_factor,
            g_idx=g_idx,
            zeros=zeros,
            sort_indices=sort_indices,
            marlin_bias=marlin_bias,
        )


@pytest.mark.flaky(reruns=2)
@pytest.mark.parametrize(
    (
        "a_type, b_type, c_type, group_blocks,"
        "m, n, k, e, topk, ep_size, act_order, is_k_full"
    ),
    marlin_moe_generate_valid_test_cases(),
)
@pytest.mark.skipif(current_platform.is_rocm(), reason="Skip for rocm")
def test_fused_marlin_moe(
    a_type,
    b_type,
    c_type,
    group_blocks,
    m,
    n,
    k,
    e,
    topk,
    ep_size,
    act_order,
    is_k_full,
):
    torch.cuda.manual_seed(1)
    group_size = group_blocks if group_blocks <= 0 else group_blocks * 16

    if c_type == scalar_types.float16:
        dtype = torch.float16
    elif c_type == scalar_types.bfloat16:
        dtype = torch.bfloat16
    else:
        raise RuntimeError("unsupported c_type")

    if a_type == scalar_types.int8:
        a_dtype = torch.int8
    elif a_type == scalar_types.float8_e4m3fn:
        a_dtype = torch.float8_e4m3fn
    else:
        a_dtype = dtype

    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10

    if ep_size > 1:
        local_e = e // ep_size
        e_ids = torch.randperm(e, device="cuda", dtype=torch.int32)[:local_e]
        e_map = torch.full((e,), -1, device="cuda", dtype=torch.int32)
        e_map[e_ids] = torch.arange(local_e, device="cuda", dtype=torch.int32)
        w1 = w1[e_ids]
        w2 = w2[e_ids]
    else:
        e_map = None

    w1_data = MarlinMoEWeightData.make(
        w=w1,
        quant_type=b_type,
        group_size=group_size,
        act_order=act_order,
        input_type=a_type,
    )

    w2_data = MarlinMoEWeightData.make(
        w=w2,
        quant_type=b_type,
        group_size=group_size,
        act_order=act_order,
        input_type=a_type,
    )

    score = torch.randn((m, e), device="cuda", dtype=dtype)

    topk_weights, topk_ids, _ = fused_topk(a, score, topk, False)

    with set_current_vllm_config(vllm_config):
        score = torch.softmax(score, dim=-1, dtype=torch.float32)
        topk_weight, topk_ids = torch.topk(score, topk)
        torch_output = torch_experts(
            a,
            w1_data.w_ref,
            w2_data.w_ref,
            topk_weight=topk_weight,
            topk_ids=topk_ids,
            global_num_experts=e,
            expert_map=e_map,
            quant_dtype=a_dtype,
            per_act_token_quant=True,
        )

    marlin_output = fused_marlin_moe(
        a,
        w1_data.qweight,
        w2_data.qweight,
        None,
        None,
        w1_data.scales,
        w2_data.scales,
        score,
        topk_weights,
        topk_ids,
        global_num_experts=e,
        expert_map=e_map,
        global_scale1=w1_data.global_scale,
        global_scale2=w2_data.global_scale,
        g_idx1=w1_data.g_idx,
        g_idx2=w2_data.g_idx,
        input_global_scale1=w1_data.a_scales_factor,
        input_global_scale2=w2_data.a_scales_factor,
        sort_indices1=w1_data.sort_indices,
        sort_indices2=w2_data.sort_indices,
        w1_zeros=w1_data.zeros,
        w2_zeros=w2_data.zeros,
        input_dtype=a_dtype,
        quant_type_id=b_type.id,
        is_k_full=is_k_full,
    )

    torch.testing.assert_close(marlin_output, torch_output, atol=4e-2, rtol=0)


@pytest.mark.flaky(reruns=2)
@pytest.mark.skipif(current_platform.is_rocm(), reason="Skip for rocm")
@pytest.mark.parametrize("m", [1, 256])
def test_fused_marlin_moe_with_bias(m):
    torch.cuda.manual_seed(0)

    e, topk = 32, 4
    n, k = 2048, 2048
    group_size = 128
    act_order = False
    is_k_full = True
    quant_type = scalar_types.uint4b8
    dtype = torch.half

    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10
    b_bias1 = torch.randn((e, 2 * n), device="cuda", dtype=dtype) / 10
    b_bias2 = torch.randn((e, k), device="cuda", dtype=dtype) / 10

    w1_data = MarlinMoEWeightData.make(
        w=w1,
        quant_type=quant_type,
        group_size=group_size,
        act_order=act_order,
        bias=b_bias1,
    )

    w2_data = MarlinMoEWeightData.make(
        w=w2,
        quant_type=quant_type,
        group_size=group_size,
        act_order=act_order,
        bias=b_bias2,
    )

    score = torch.randn((m, e), device="cuda", dtype=dtype)

    topk_weights, topk_ids, _ = fused_topk(a, score, topk, False)

    with set_current_vllm_config(vllm_config):
        torch_output = torch_moe(
            a, w1_data.w_ref, w2_data.w_ref, score, topk, b_bias1, b_bias2
        )

    marlin_output = fused_marlin_moe(
        a,
        w1_data.qweight,
        w2_data.qweight,
        w1_data.marlin_bias,
        w2_data.marlin_bias,
        w1_data.scales,
        w2_data.scales,
        score,
        topk_weights,
        topk_ids,
        global_num_experts=e,
        expert_map=None,
        global_scale1=w1_data.global_scale,
        global_scale2=w2_data.global_scale,
        g_idx1=w1_data.g_idx,
        g_idx2=w2_data.g_idx,
        sort_indices1=w1_data.sort_indices,
        sort_indices2=w2_data.sort_indices,
        w1_zeros=w1_data.zeros,
        w2_zeros=w2_data.zeros,
        quant_type_id=quant_type.id,
        is_k_full=is_k_full,
    )

    torch.testing.assert_close(marlin_output, torch_output, atol=5e-2, rtol=0)


def test_moe_align_block_size_opcheck():
    num_experts = 4
    block_size = 4
    topk_ids = torch.randint(0, num_experts, (3, 4), dtype=torch.int32, device="cuda")

    max_num_tokens_padded = topk_ids.numel() + num_experts * (block_size - 1)
    sorted_ids = torch.empty(
        (max_num_tokens_padded,), dtype=torch.int32, device=topk_ids.device
    )
    sorted_ids.fill_(topk_ids.numel())
    max_num_m_blocks = max_num_tokens_padded // block_size
    expert_ids = torch.empty(
        (max_num_m_blocks,), dtype=torch.int32, device=topk_ids.device
    )
    num_tokens_post_pad = torch.empty((1), dtype=torch.int32, device=topk_ids.device)

    opcheck(
        torch.ops._moe_C.moe_align_block_size,
        (
            topk_ids,
            num_experts,
            block_size,
            sorted_ids,
            expert_ids,
            num_tokens_post_pad,
        ),
    )


def test_batched_moe_align_block_size_opcheck():
    max_tokens_per_batch = 512
    num_experts = 4
    block_size = 16

    expert_num_tokens = torch.randint(
        low=0,
        high=max_tokens_per_batch,
        size=(num_experts,),
        dtype=torch.int32,
        device="cuda",
    )

    max_num_tokens_padded = num_experts * max(max_tokens_per_batch, block_size)
    sorted_ids = torch.empty((max_num_tokens_padded,), dtype=torch.int32, device="cuda")

    assert max_num_tokens_padded % block_size == 0
    max_num_m_blocks = max_num_tokens_padded // block_size
    expert_ids = torch.empty((max_num_m_blocks,), dtype=torch.int32, device="cuda")

    num_tokens_post_pad = torch.empty((1), dtype=torch.int32, device="cuda")

    opcheck(
        torch.ops._moe_C.batched_moe_align_block_size,
        (
            max_tokens_per_batch,
            block_size,
            expert_num_tokens,
            sorted_ids,
            expert_ids,
            num_tokens_post_pad,
        ),
    )


@pytest.mark.parametrize("m", [1, 33, 222])
@pytest.mark.parametrize("topk", TOP_KS)
@pytest.mark.parametrize("k", [128, 511, 1024])
@pytest.mark.parametrize("dtype", [torch.float32, torch.bfloat16])
@pytest.mark.skipif(current_platform.is_rocm(), reason="Skip for rocm")
def test_moe_sum(m: int, topk: int, k: int, dtype: torch.dtype):
    input = torch.randn((m, topk, k), device="cuda", dtype=dtype)
    actual = torch.empty((m, k), device="cuda", dtype=dtype)

    expected = input.sum(dim=1)
    torch.ops._moe_C.moe_sum(input, actual)

    torch.testing.assert_close(actual, expected, atol=2e-2, rtol=0)

    opcheck(torch.ops._moe_C.moe_sum, (input, actual))


@pytest.mark.parametrize("m", [1, 33])
@pytest.mark.parametrize("n,k", [(128, 128)])
@pytest.mark.parametrize("e", [8])
@pytest.mark.parametrize("topk", [2])
@pytest.mark.parametrize("dtype", [torch.float32, torch.bfloat16])
@pytest.mark.parametrize("with_bias", [False, True])
@pytest.mark.parametrize("activation", ["silu"])
@pytest.mark.skipif(not current_platform.is_cpu(), reason="CPU only test")
def test_cpu_fused_moe_basic(m, n, k, e, topk, dtype, with_bias, activation):
    from vllm.model_executor.layers.fused_moe.cpu_fused_moe import CPUFusedMOE

    device = "cpu"
    torch.manual_seed(7)

    a = torch.randn((m, k), device=device, dtype=dtype) / 10
    w13 = torch.randn((e, 2 * n, k), device=device, dtype=dtype) / 10
    w2 = torch.randn((e, k, n), device=device, dtype=dtype) / 10
    router_logits = torch.randn((m, e), device=device, dtype=dtype)

    b1 = b2 = None
    if with_bias:
        b1 = torch.randn((e, 2 * n), device=device, dtype=dtype) / 10
        b2 = torch.randn((e, k), device=device, dtype=dtype) / 10

    ref = (
        torch_moe(a, w13, w2, router_logits, topk, b1, b2)
        if with_bias
        else torch_moe(a, w13, w2, router_logits, topk)
    )

    class _Dummy(torch.nn.Module):
        def __init__(self, w13, w2, b1=None, b2=None):
            super().__init__()
            self.w13_weight = torch.nn.Parameter(w13, requires_grad=False)
            self.w2_weight = torch.nn.Parameter(w2, requires_grad=False)
            if b1 is not None:
                self.w13_bias = torch.nn.Parameter(b1, requires_grad=False)
            if b2 is not None:
                self.w2_bias = torch.nn.Parameter(b2, requires_grad=False)

    layer = _Dummy(w13, w2, b1, b2).to(dtype)
    fused = CPUFusedMOE(layer)
    out = fused(
        layer=layer,
        x=a,
        use_grouped_topk=False,
        top_k=topk,
        router_logits=router_logits,
        renormalize=False,
        global_num_experts=e,
        expert_map=None,
        custom_routing_function=None,
        scoring_func="softmax",
        routed_scaling_factor=1.0,
        e_score_correction_bias=None,
        apply_router_weight_on_input=False,
        activation=activation,
    )

    # Tolerances: fp32 tight; bf16 looser (esp. with bias)
    if dtype == torch.float32:
        atol = 1e-3
    elif with_bias:
        atol = 8e-2
    else:
        atol = 5e-2
    torch.testing.assert_close(out, ref, atol=atol, rtol=0)


@pytest.mark.parametrize("m", [16, 32, 64])
@pytest.mark.parametrize("n", [128])
@pytest.mark.parametrize("k", [128])
@pytest.mark.parametrize("e", [8, 12, 16, 32])
@pytest.mark.parametrize("topk", [2, 4])
@pytest.mark.parametrize("max_tokens_per_batch", [16, 32, 64])
@pytest.mark.skipif(current_platform.is_rocm(), reason="Skip for rocm")
def test_batched_fused_marlin_moe(
    m: int, n: int, k: int, e: int, topk: int, max_tokens_per_batch: int
):
    print(
        f"testing m={m}, n={n}, k={k}, e={e}, "
        f"topk={topk}, "
        f"max_tokens_per_batch={max_tokens_per_batch}"
    )
    torch.cuda.manual_seed(0)

    dtype = torch.bfloat16
    quant_dtype = scalar_types.float4_e2m1f
    group_size = 32

    a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
    w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 20
    w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 20

    w1_data = MarlinMoEWeightData.make(
        w=w1, quant_type=quant_dtype, group_size=group_size, act_order=None
    )
    w2_data = MarlinMoEWeightData.make(
        w=w2, quant_type=quant_dtype, group_size=group_size, act_order=None
    )

    score = torch.randn((m, e), device="cuda", dtype=dtype)
    topk_weights, topk_ids, _ = fused_topk(a, score, topk, False)

    class BatchedRun:
        @staticmethod
        def _make_expert_num_tokens_cpu(
            e: int,  # num_experts
            topk_ids_cpu: torch.Tensor,
        ) -> torch.Tensor:
            expert_num_tokens_cpu = torch.zeros((e,), dtype=torch.int32, device="cpu")
            for topk_id in torch.flatten(topk_ids_cpu):
                expert_num_tokens_cpu[topk_id] += 1
            return expert_num_tokens_cpu

        def __init__(
            self,
            max_tokens_per_batch: int,
            num_experts: int,
            _topk_ids: torch.Tensor,
            _topk_weights: torch.Tensor,
        ):
            self.max_tokens_per_batch = max_tokens_per_batch
            self.e = num_experts
            self.topk_ids_cpu = _topk_ids.to("cpu")
            self.topk_weights_cpu = _topk_weights.to("cpu")
            self.expert_num_tokens_cpu = self._make_expert_num_tokens_cpu(
                self.e, self.topk_ids_cpu
            )

        def is_valid(self):
            """
            Return True only if the input can be represented in a Batched
            format.
            """
            return torch.all(self.expert_num_tokens_cpu <= self.max_tokens_per_batch)

        def _scatter(self, hidden_states: torch.Tensor) -> torch.Tensor:
            hidden_states_cpu = hidden_states.to("cpu")
            K = hidden_states_cpu.size(1)
            batched_hidden_states_cpu = torch.empty(
                (e, max_tokens_per_batch, K),
                dtype=hidden_states_cpu.dtype,
                device="cpu",
            )

            counter_cpu = torch.zeros_like(self.expert_num_tokens_cpu)
            for t_idx, token in enumerate(hidden_states_cpu):
                for topk_id in self.topk_ids_cpu[t_idx]:
                    pos_in_batch = counter_cpu[topk_id]
                    batched_hidden_states_cpu[topk_id, pos_in_batch] = token
                    counter_cpu[topk_id] += 1
            assert torch.allclose(counter_cpu, self.expert_num_tokens_cpu)
            return batched_hidden_states_cpu.to("cuda")

        def _gather(
            self, batched_outputs: torch.Tensor, gather_outputs: torch.Tensor
        ) -> torch.Tensor:
            batched_outputs_cpu = batched_outputs.to("cpu")
            gather_outputs_cpu = torch.zeros_like(gather_outputs)

            counter_cpu = torch.zeros((e,), device="cpu", dtype=torch.int32)
            md = gather_outputs_cpu.size(0)
            for t_idx in range(md):
                token = None
                for topk_id, topk_weight in zip(
                    self.topk_ids_cpu[t_idx], self.topk_weights_cpu[t_idx]
                ):
                    pos_in_batch = counter_cpu[topk_id]
                    t = batched_outputs_cpu[topk_id, pos_in_batch] * topk_weight
                    if token is None:
                        token = t
                    else:
                        token += t
                    counter_cpu[topk_id] += 1
                assert token is not None
                gather_outputs_cpu[t_idx] = token
            gather_outputs.copy_(gather_outputs_cpu)
            return gather_outputs

        def run(
            self, hidden_states: torch.Tensor, fused_marlin_moe_kwargs: dict[Any, Any]
        ) -> torch.Tensor:
            assert hidden_states.ndim == 2
            assert self.is_valid()

            batched_hidden_states = self._scatter(hidden_states)

            kwargs = fused_marlin_moe_kwargs | {
                "hidden_states": batched_hidden_states,
                "expert_num_tokens": self.expert_num_tokens_cpu.to("cuda"),
            }
            batched_outputs = batched_fused_marlin_moe(**kwargs)

            output = torch.zeros_like(hidden_states)
            output = self._gather(batched_outputs, output)
            return output

    kwargs = {
        "w1": w1_data.qweight,
        "w2": w2_data.qweight,
        "bias1": None,
        "bias2": None,
        "w1_scale": w1_data.scales,
        "w2_scale": w2_data.scales,
        "gating_output": score,
        "global_num_experts": e,
        "expert_map": None,
        "global_scale1": w1_data.global_scale,
        "global_scale2": w2_data.global_scale,
        "g_idx1": w1_data.g_idx,
        "g_idx2": w2_data.g_idx,
        "sort_indices1": w1_data.sort_indices,
        "sort_indices2": w2_data.sort_indices,
        "w1_zeros": w1_data.zeros,
        "w2_zeros": w2_data.zeros,
        "quant_type_id": quant_dtype.id,
        "is_k_full": True,
    }

    # Reference
    fused_marlin_moe_kwargs = kwargs | {
        "hidden_states": a,
        "topk_ids": topk_ids,
        "topk_weights": topk_weights,
    }
    ref_marlin_output = fused_marlin_moe(**fused_marlin_moe_kwargs)

    # Batched
    br = BatchedRun(max_tokens_per_batch, e, topk_ids, topk_weights)
    if not br.is_valid():
        pytest.skip("Cannot represent data in Batched Format.")
    marlin_output = br.run(a, kwargs)

    torch.testing.assert_close(marlin_output, ref_marlin_output, atol=1e-3, rtol=0)
