import torch
import torch.backends
import tilelang
from tilelang import tvm as tvm
import tilelang.testing
import tilelang.language as T
from tilelang.intrinsics import (
    make_mma_swizzle_layout as make_swizzle_layout,)

from tilelang.intrinsics.mma_macro_generator import (
    INT4TensorCoreIntrinEmitter,
    INT4TensorCoreIntrinEmitterWithLadderTransform,
)
from tilelang.transform import simplify_prim_func

tilelang.testing.set_random_seed(42)
tilelang.disable_cache()


# @simplify_prim_func
def tl_matmul(
    M,
    N,
    K,
    in_dtype,
    out_dtype,
    accum_dtype,
):
    assert in_dtype in [
        "float16",
        "int8",
    ], "Currently only float16 and int8 are supported"
    assert out_dtype in [
        "float16",
        "float32",
        "int32",
    ], "Currently only float16, float32 and int32 are supported"

    K = K // 2

    micro_size_x = micro_size_y = micro_size_k = 16

    if accum_dtype == "int32":
        micro_size_k = 32

    # This is a debug config
    block_row_warps = 2
    block_col_warps = 2
    warp_row_tiles = 64
    warp_col_tiles = 64
    chunk = 32 if in_dtype == "float16" else 64
    shared_scope = "shared.dyn"

    # Pipeline Stage
    stage = 2

    block_M = block_row_warps * warp_row_tiles
    block_N = block_col_warps * warp_col_tiles
    block_K = chunk

    A_shape = (M, K)  # int8 storage represents int4*2
    B_shape = (N, K)  # int8 storage represents int4*2
    A_shared_shape = (block_M, block_K)
    B_shared_shape = (block_N, block_K)
    C_shared_shape = (
        block_M // micro_size_x,
        block_N // micro_size_y,
        micro_size_x,
        micro_size_y,
    )

    warp_size = 32
    threads = warp_size * (block_row_warps * block_col_warps)
    local_size_a = (micro_size_x * micro_size_k) // warp_size
    local_size_b = (micro_size_y * micro_size_k) // warp_size
    local_size_c = (micro_size_x * micro_size_y) // warp_size
    warp_rows = warp_row_tiles // micro_size_x
    warp_cols = warp_col_tiles // micro_size_y

    # MMA Wrapper to Auto Generate Code for MMA
    mma_emitter = INT4TensorCoreIntrinEmitter(
        a_dtype=in_dtype,
        b_dtype=in_dtype,
        accum_dtype=accum_dtype,
        a_transposed=False,
        b_transposed=True,
        block_row_warps=block_row_warps,
        block_col_warps=block_col_warps,
        warp_row_tiles=warp_row_tiles,
        warp_col_tiles=warp_col_tiles,
        chunk=chunk,
    )

    @T.prim_func
    def main(
            A: T.Tensor(A_shape, in_dtype),
            B: T.Tensor(B_shape, in_dtype),
            C: T.Tensor((M, N), out_dtype),
    ):
        with T.Kernel(T.ceildiv(N, block_N), T.ceildiv(M, block_M), threads=threads) as (bx, by):

            A_shared = T.alloc_shared(A_shared_shape, in_dtype, scope=shared_scope)
            B_shared = T.alloc_shared(B_shared_shape, in_dtype, scope=shared_scope)
            C_shared = T.alloc_shared(C_shared_shape, out_dtype, scope=shared_scope)
            A_local = T.alloc_local((warp_rows * local_size_a), in_dtype)
            B_local = T.alloc_local((warp_cols * local_size_b), in_dtype)
            C_local = T.alloc_local((warp_rows * warp_cols * local_size_c), accum_dtype)

            T.annotate_layout({
                A_shared: make_swizzle_layout(A_shared),
                B_shared: make_swizzle_layout(B_shared),
            })

            # Improve L2 Cache
            T.use_swizzle(panel_size=10)

            T.clear(C_local)

            for ko in T.Pipelined(T.ceildiv(K, block_K), num_stages=stage):

                # Load A into shared memory
                for i, k in T.Parallel(block_M, block_K):
                    A_shared[i, k] = A[by * block_M + i, ko * block_K + k]

                # Load B into shared memory
                for j, k in T.Parallel(block_N, block_K):
                    B_shared[j, k] = B[bx * block_N + j, ko * block_K + k]

                for ki in T.serial(0, (block_K // micro_size_k)):

                    # Load A into fragment
                    mma_emitter.ldmatrix_a(
                        A_local,
                        A_shared,
                        ki,
                    )

                    # Load B into fragment
                    mma_emitter.ldmatrix_b(
                        B_local,
                        B_shared,
                        ki,
                    )

                    # Perform Matrix Multiplication
                    mma_emitter.mma(A_local, B_local, C_local)

            # Perform STMatrix
            mma_emitter.stmatrix(
                C_local,
                C_shared,
            )

            # Store shared into global
            for i, j in T.Parallel(block_M, block_N):
                C[by * block_M + i, bx * block_N + j] = C_shared[
                    i // micro_size_x,
                    j // micro_size_y,
                    i % micro_size_x,
                    j % micro_size_y,
                ]

    return main


def assert_tl_matmul_correctness(M, N, K, in_dtype, out_dtype, accum_dtype):
    matmul = tl_matmul(M, N, K, in_dtype, out_dtype, accum_dtype)
    kernel = tilelang.compile(
        matmul,
        out_idx=[2],
        pass_configs={
            tilelang.PassConfigKey.TL_DEBUG_MERGE_SHARED_MEMORY_ALLOCATIONS: True,
        })
    print(kernel.get_kernel_source())
    profiler = kernel.get_profiler()

    src_code = kernel.get_kernel_source()
    # src_code is the generated cuda source
    assert src_code is not None

    A = torch.randint(0, 4, (M, K), device="cuda", dtype=getattr(torch, in_dtype))
    B = torch.randint(0, 4, (N, K), device="cuda", dtype=getattr(torch, in_dtype))

    compressed_A = (A[:, ::2] & 0x0F) + ((A[:, 1::2] & 0x0F) << 4)
    compressed_B = (B[:, ::2] & 0x0F) + ((B[:, 1::2] & 0x0F) << 4)
    C = kernel(compressed_A, compressed_B)
    print(C)
    latency = profiler.do_bench()
    print(latency)
    # Ensure that the latency is not None
    assert latency is not None

    # Get Reference Result
    ref_c = torch.matmul(A.to(torch.float32), B.T.to(torch.float32)).to(getattr(torch, accum_dtype))

    print(ref_c)
    torch.testing.assert_close(C, ref_c, rtol=1e-2, atol=1e-2)


def test_assert_tl_matmul_correctness():
    assert_tl_matmul_correctness(128, 128, 128, "int8", "int32", "int32")
    assert_tl_matmul_correctness(128, 128, 64, "int8", "int32", "int32")


@simplify_prim_func
def tl_matmul_weight_only_transform(
    M,
    N,
    K,
    in_dtype,
    out_dtype,
    accum_dtype,
):
    K = K // 2
    assert in_dtype in [
        "float16",
        "int8",
    ], "Currently only float16 and int8 are supported"
    assert out_dtype in [
        "float16",
        "float32",
        "int32",
    ], "Currently only float16, float32 and int32 are supported"

    micro_size_x = micro_size_y = micro_size_k = 16

    if out_dtype == "int32":
        micro_size_k = 32

    transform_b = 3

    # This is a debug config
    block_row_warps = 2
    block_col_warps = 2
    warp_row_tiles = 64
    warp_col_tiles = 64
    chunk = 32 if in_dtype == "float16" else 64
    shared_scope = "shared.dyn"

    # Pipeline Stage
    stage = 2

    block_M = block_row_warps * warp_row_tiles
    block_N = block_col_warps * warp_col_tiles
    block_K = chunk

    A_shape = (M, K)
    B_shape = (N // micro_size_y, K // micro_size_k, micro_size_y, micro_size_k)
    A_shared_shape = (
        block_M,
        block_K,
    )
    B_shared_shape = (
        block_N // micro_size_y,
        block_K // micro_size_k,
        micro_size_y,
        micro_size_k,
    )
    C_shared_shape = (
        block_M // micro_size_x,
        block_N // micro_size_y,
        micro_size_x,
        micro_size_y,
    )
    warp_size = 32
    threads = warp_size * (block_row_warps * block_col_warps)
    local_size_a = (micro_size_x * micro_size_k) // warp_size
    local_size_b = (micro_size_y * micro_size_k) // warp_size
    local_size_c = (micro_size_x * micro_size_y) // warp_size
    warp_rows = warp_row_tiles // micro_size_x
    warp_cols = warp_col_tiles // micro_size_y

    # MMA Wrapper to Auto Generate Code for MMA
    mma_emitter = INT4TensorCoreIntrinEmitterWithLadderTransform(
        a_dtype=in_dtype,
        b_dtype=in_dtype,
        accum_dtype=accum_dtype,
        a_transposed=False,
        b_transposed=True,
        block_row_warps=block_row_warps,
        block_col_warps=block_col_warps,
        warp_row_tiles=warp_row_tiles,
        warp_col_tiles=warp_col_tiles,
        chunk=chunk,
        transform_kind_b=transform_b,
    )

    @T.prim_func
    def main(
            A: T.Tensor(A_shape, in_dtype),
            B: T.Tensor(B_shape, in_dtype),
            C: T.Tensor((M, N), out_dtype),
    ):
        with T.Kernel(T.ceildiv(N, block_N), T.ceildiv(M, block_M), threads=threads) as (bx, by):

            A_shared = T.alloc_shared(A_shared_shape, in_dtype, scope=shared_scope)
            B_shared = T.alloc_shared(B_shared_shape, in_dtype, scope=shared_scope)
            C_shared = T.alloc_shared(C_shared_shape, out_dtype, scope=shared_scope)
            A_local = T.alloc_local((warp_rows * local_size_a), in_dtype)
            B_local = T.alloc_local((warp_cols * local_size_b), in_dtype)
            C_local = T.alloc_local((warp_rows * warp_cols * local_size_c), accum_dtype)

            T.annotate_layout({
                A_shared: make_swizzle_layout(A_shared),
                B_shared: make_swizzle_layout(B_shared),
            })

            # Improve L2 Cache
            T.use_swizzle(panel_size=10)

            T.clear(C_local)

            for ko in T.Pipelined(T.ceildiv(K, block_K), num_stages=stage):

                # Load A into shared memory
                for i, k in T.Parallel(block_M, block_K):
                    A_shared[i, k] = A[by * block_M + i, ko * block_K + k]

                # Load B into shared memory
                for j, k, jj, kk in T.Parallel(block_N // micro_size_y, block_K // micro_size_k,
                                               micro_size_y, micro_size_k):
                    B_shared[j, k, jj, kk] = B[bx * (block_N // micro_size_y) + j,
                                               ko * (block_K // micro_size_k) + k, jj, kk]

                for ki in T.serial(0, (block_K // micro_size_k)):

                    # Load A into fragment
                    mma_emitter.ldmatrix_a(
                        A_local,
                        A_shared,
                        ki,
                    )

                    # Load B into fragment
                    mma_emitter.ldmatrix_b(
                        B_local,
                        B_shared,
                        ki,
                    )

                    # Perform Matrix Multiplication
                    mma_emitter.mma(A_local, B_local, C_local)

            # Perform STMatrix
            mma_emitter.stmatrix(
                C_local,
                C_shared,
            )

            # Store shared into global
            for i, j in T.Parallel(block_M, block_N):
                C[by * block_M + i, bx * block_N + j] = C_shared[
                    i // micro_size_x,
                    j // micro_size_y,
                    i % micro_size_x,
                    j % micro_size_y,
                ]

    return main


def assert_tl_matmul_weight_only_transform_correctness(M, N, K, in_dtype, out_dtype, accum_dtype):
    import bitblas
    matmul = tl_matmul_weight_only_transform(M, N, K, in_dtype, out_dtype, accum_dtype)
    kernel = tilelang.compile(matmul, out_idx=[2])
    profiler = kernel.get_profiler()

    src_code = kernel.get_kernel_source()
    # src_code is the generated cuda source
    assert src_code is not None
    transform_b = 3

    A = torch.randint(0, 4, (M, K), device="cuda", dtype=getattr(torch, in_dtype))
    B = torch.randint(0, 4, (N, K), device="cuda", dtype=getattr(torch, in_dtype))
    compressed_A = (A[:, ::2] & 0x0F) + ((A[:, 1::2] & 0x0F) << 4)
    compressed_B = (B[:, ::2] & 0x0F) + ((B[:, 1::2] & 0x0F) << 4)

    ladder_permutate_config = bitblas.ops.LadderPermutateConfig(
        M=N,
        N=(K // 2),
        datatype="int8",
        storage_dtype="int8",
        transform_kind=transform_b,
        transpose_matrix=True,
    )

    ladder_permutate = bitblas.ops.LadderPermutate(ladder_permutate_config)
    LB = ladder_permutate(compressed_B.cpu()).cuda()
    C = kernel(compressed_A, LB)

    latency = profiler.do_bench()
    print(f"Latency: {latency}")
    # Ensure that the latency is not None
    assert latency is not None

    # Get Reference Result
    ref_c = torch.matmul(A.to(torch.float32), B.T.to(torch.float32)).to(getattr(torch, accum_dtype))
    print(C)
    print(ref_c)
    torch.testing.assert_close(C, ref_c, rtol=1e-2, atol=1e-2)


@tilelang.testing.requires_package("bitblas")
@tilelang.testing.requires_llvm
def test_assert_tl_matmul_weight_only_transform():
    assert_tl_matmul_weight_only_transform_correctness(128, 128, 128, "int8", "int32", "int32")


if __name__ == "__main__":
    # tilelang.testing.main()
    assert_tl_matmul_correctness(128, 128, 128, "int8", "int32", "int32")
