import pytest
import torch

from colossalai.auto_parallel.tensor_shard.sharding_strategy import OperationData, OperationDataType, TrainCycleItem
from colossalai.testing.utils import clear_cache_before_run, parameterize
from tests.test_auto_parallel.test_tensor_shard.test_metainfo.utils import print_results

if torch.__version__ >= '1.12.0':
    from colossalai.auto_parallel.meta_profiler import ShardMetaInfo, meta_register


@pytest.mark.skipif(torch.__version__ < '1.12.0', reason="need pytorch 1.12.0 or higher for aten level operations")
@clear_cache_before_run()
@parameterize(
    'tensor_shapes',
    [
        [[128], [128]],    # dot product
        [[64, 128], [128]],    # mat-vec
        [[128], [128, 64]],    # vec-mat
        [[64, 64, 128], [128]],    # batched mat-vec
        [[128], [64, 128, 64]],    # vec-batched mat
        [[64, 128], [128, 192]],    # mat-mat
        [[64, 64, 128], [128, 192]],    # batched mat-mat
        [[64, 128], [64, 128, 192]],    # mat-batched mat
        [[64, 64, 128], [64, 128, 192]],    # batched mat-batched mat (matched batch dims)
        [[64, 1, 64, 128], [64, 128, 192]],    # batched mat-batched mat (unmatched batch dims)
    ])
def test_matmul_function_meta_info(tensor_shapes):
    meta_func = meta_register.get(torch.matmul)

    # construct meta tensors
    input_tensor = torch.rand(*tensor_shapes[0], device="meta")
    other_tensor = torch.rand(*tensor_shapes[1], device="meta")
    output_tensor = torch.matmul(input_tensor, other_tensor)

    # construct operation data
    input_data = OperationData(
        name="input",
        data=input_tensor,
        type=OperationDataType.ARG,
        logical_shape=input_tensor.shape,
    )
    other_data = OperationData(
        name="other",
        data=other_tensor,
        type=OperationDataType.ARG,
        logical_shape=other_tensor.shape,
    )
    output_data = OperationData(
        name="output",
        data=output_tensor,
        type=OperationDataType.OUTPUT,
        logical_shape=output_tensor.shape,
    )

    # construct args and kwargs
    args = [input_data, other_data, output_data]
    kwargs = {'inplace': False}

    # estimated results
    compute_cost, memory_cost, fwd_in, fwd_buffer, fwd_out = meta_func(*args, **kwargs)

    # actual results
    input_real_tensor = torch.rand(*tensor_shapes[0], device="cuda:0")
    other_real_tensor = torch.rand(*tensor_shapes[1], device="cuda:0")

    input_real_tensor.requires_grad = True
    other_real_tensor.requires_grad = True

    # fwd
    torch.cuda.reset_peak_memory_stats()
    mem_stamp0 = torch.cuda.memory_allocated()
    output_real_tensor = torch.matmul(input_real_tensor, other_real_tensor)
    fwd_allocated = torch.cuda.memory_allocated() - mem_stamp0
    fwd_peak = torch.cuda.max_memory_allocated() - mem_stamp0

    # bwd
    upstream_grad = torch.rand_like(output_real_tensor)
    torch.cuda.reset_peak_memory_stats()
    mem_stamp0 = torch.cuda.memory_allocated()
    torch.autograd.backward(output_real_tensor, upstream_grad)
    bwd_allocated = torch.cuda.memory_allocated() - mem_stamp0
    bwd_peak = torch.cuda.max_memory_allocated() - mem_stamp0

    compute_cost: TrainCycleItem
    memory_cost: TrainCycleItem

    print_results([input_real_tensor, other_real_tensor], [output_real_tensor], compute_cost, memory_cost,
                  fwd_allocated, fwd_peak, bwd_allocated, bwd_peak)


if __name__ == '__main__':
    test_matmul_function_meta_info()
