#
# Copyright (c) 2021-2023, NVIDIA CORPORATION. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

import numpy as np
import tensorrt as trt
from cuda import cudart

logger = trt.Logger(trt.Logger.ERROR)
builder = trt.Builder(logger)
network = builder.create_network(1 << int(trt.NetworkDefinitionCreationFlag.EXPLICIT_BATCH))
profile = builder.create_optimization_profile()
config = builder.create_builder_config()

inputTensor = network.add_input("inputT0", trt.float32, [-1, -1, -1])
profile.set_shape(inputTensor.name, [1, 1, 1], [3, 4, 5], [6, 8, 10])
print("OptimizationProfile is available? %s" % bool(profile))  # an equivalent API: print(profile.__nonzero__())
config.add_optimization_profile(profile)

identityLayer = network.add_identity(inputTensor)
network.mark_output(identityLayer.get_output(0))

engineString = builder.build_serialized_network(network, config)
engine = trt.Runtime(logger).deserialize_cuda_engine(engineString)
nIO = engine.num_io_tensors
lTensorName = [engine.get_tensor_name(i) for i in range(nIO)]
nInput = [engine.get_tensor_mode(lTensorName[i]) for i in range(nIO)].count(trt.TensorIOMode.INPUT)

context = engine.create_execution_context()

def run(shape):
    context.set_input_shape(lTensorName[0], shape)

    for i in range(nIO):
        print("[%2d]%s->" % (i, "Input " if i < nInput else "Output"), engine.get_tensor_dtype(lTensorName[i]), engine.get_tensor_shape(lTensorName[i]), context.get_tensor_shape(lTensorName[i]), lTensorName[i])

    bufferH = []
    bufferH.append(np.ascontiguousarray(np.arange(np.prod(shape), dtype=np.float32).reshape(shape)))
    for i in range(nInput, nIO):
        bufferH.append(np.empty(context.get_tensor_shape(lTensorName[i]), dtype=trt.nptype(engine.get_tensor_dtype(lTensorName[i]))))
    bufferD = []
    for i in range(nIO):
        bufferD.append(cudart.cudaMalloc(bufferH[i].nbytes)[1])

    for i in range(nInput):
        cudart.cudaMemcpy(bufferD[i], bufferH[i].ctypes.data, bufferH[i].nbytes, cudart.cudaMemcpyKind.cudaMemcpyHostToDevice)

    for i in range(nIO):
        context.set_tensor_address(lTensorName[i], int(bufferD[i]))

    context.execute_async_v3(0)

    for i in range(nInput, nIO):
        cudart.cudaMemcpy(bufferH[i].ctypes.data, bufferD[i], bufferH[i].nbytes, cudart.cudaMemcpyKind.cudaMemcpyDeviceToHost)

    for i in range(nIO):
        print(lTensorName[i])
        print(bufferH[i])

    for b in bufferD:
        cudart.cudaFree(b)

    return

# do inference with a shape
run([3, 4, 5])

# do inference with another shape
run([6, 8, 10])
