import collections

import caffe2.python.hypothesis_test_util as hu
import hypothesis.strategies as st
import numpy as np
from caffe2.python import core, dyndep, workspace
from caffe2.quantization.server import utils as dnnlowp_utils
from caffe2.quantization.server.dnnlowp_test_utils import (
    avoid_vpmaddubsw_overflow_fc,
    check_quantized_results_close,
    run_conv_or_fc,
)
from hypothesis import given


dyndep.InitOpsLibrary("//caffe2/caffe2/quantization/server:dnnlowp_ops")
workspace.GlobalInit(["caffe2", "--caffe2_omp_num_threads=11"])


class DNNLowPFullyConnectedOpTest(hu.HypothesisTestCase):
    # correctness test with no quantization error in inputs
    @given(
        input_channels=st.sampled_from([3, 4, 5, 8, 16, 32]),
        output_channels=st.integers(2, 16),
        batch_size=st.integers(0, 16),
        in_quantized=st.booleans(),
        out_quantized=st.booleans(),
        weight_quantized=st.booleans(),
        prepack_weight=st.booleans(),
        preserve_activation_sparsity=st.booleans(),
        preserve_weight_sparsity=st.booleans(),
        fuse_relu=st.booleans(),
        output_packed_bias=st.booleans(),
        use_input_qparam=st.booleans(),
        **hu.gcs_cpu_only
    )
    def test_dnnlowp_fully_connected_int(
        self,
        input_channels,
        output_channels,
        batch_size,
        in_quantized,
        out_quantized,
        weight_quantized,
        prepack_weight,
        preserve_activation_sparsity,
        preserve_weight_sparsity,
        fuse_relu,
        output_packed_bias,
        use_input_qparam,
        gc,
        dc,
    ):
        # X and W have scale 1, so exactly represented after quantization
        X_min = 0 if preserve_activation_sparsity else -77
        X_max = X_min + 255
        X = np.round(
            np.random.rand(batch_size, input_channels) * (X_max - X_min) + X_min
        )
        X = X.astype(np.float32)
        # input channels 0 and 1 are all X_min to avoid overflow from vpmaddubsw
        # when multiplied with W_min and W_max
        X[:, 0] = X_min
        if batch_size != 0:
            X[0, 1] = X_max

        if preserve_weight_sparsity:
            W_min = -128
            W_max = 100
        else:
            W_min = -100
            W_max = W_min + 255
        W = np.round(
            np.random.rand(output_channels, input_channels) * (W_max - W_min) + W_min
        )
        W = W.astype(np.float32)
        W[0, 0] = W_min
        W[1, 0] = W_max

        # Make sure we won't have overflows from vpmaddubsw instruction used in
        # fbgemm
        avoid_vpmaddubsw_overflow_fc(
            batch_size,
            input_channels,
            output_channels,
            X,
            X_min,
            X_max,
            W,
            W_min,
            W_max,
        )

        b = np.random.randn(output_channels).astype(np.float32)

        Output = collections.namedtuple("Output", ["Y", "op_type", "engine"])
        outputs = []

        op_engine_list = [("FC", "")]
        if fuse_relu:
            op_engine_list += [("Int8FCRelu", "DNNLOWP")]
        else:
            op_engine_list += [
                ("FC", "DNNLOWP"),
                ("FC", "DNNLOWP_16"),
                ("Int8FC", "DNNLOWP"),
            ]

        for op_type, engine in op_engine_list:
            init_net = core.Net("test_init_net")
            net = core.Net("test_net")

            do_quantize = "DNNLOWP" in engine and in_quantized
            do_dequantize = "DNNLOWP" in engine and out_quantized
            do_quantize_weight = (
                engine == "DNNLOWP" and weight_quantized and len(outputs) > 0
            )
            do_prepack_weight = engine == "DNNLOWP" and prepack_weight

            if do_quantize:
                quantize = core.CreateOperator(
                    "Quantize",
                    ["X"],
                    ["X_q"],
                    preserve_activation_sparsity=preserve_activation_sparsity,
                    engine=engine,
                    device_option=gc,
                )
                net.Proto().op.extend([quantize])

            X_min = 0 if X.size == 0 else X.min()
            X_max = 0 if X.size == 0 else X.max()
            x_q_param = dnnlowp_utils.choose_quantization_params(
                X_min, X_max, preserve_activation_sparsity
            )
            w_q_param = None
            if do_quantize_weight:
                (
                    int8_given_tensor_fill,
                    w_q_param,
                ) = dnnlowp_utils.create_int8_given_tensor_fill(
                    W, "W_q", preserve_weight_sparsity
                )
                init_net.Proto().op.extend([int8_given_tensor_fill])

                # Bias
                int8_bias_tensor_fill = dnnlowp_utils.create_int8_bias_tensor_fill(
                    b, "b_q", x_q_param, w_q_param
                )
                init_net.Proto().op.extend([int8_bias_tensor_fill])

            if do_prepack_weight:
                inputs = ["W_q" if do_quantize_weight else "W"]
                if do_dequantize:
                    inputs += ["b_q" if do_quantize_weight else "b"]
                pack = core.CreateOperator(
                    "Int8FCPackWeight",
                    inputs,
                    ["W_packed", "B_q32"]
                    if do_dequantize and output_packed_bias
                    else ["W_packed"],
                    preserve_weight_sparsity=preserve_weight_sparsity,
                    in_scale=x_q_param.scale,
                    engine=engine,
                )
                init_net.Proto().op.extend([pack])

            if use_input_qparam and do_dequantize and op_type != "FC":
                fc = core.CreateOperator(
                    op_type,
                    [
                        "X_q" if do_quantize else "X",
                        "W_packed"
                        if do_prepack_weight
                        else ("W_q" if do_quantize_weight else "W"),
                        "b_q" if do_quantize_weight else "b",
                        "quant_param",
                    ],
                    ["Y_q" if do_dequantize else "Y"],
                    dequantize_output=not do_dequantize,
                    preserve_activation_sparsity=preserve_activation_sparsity,
                    preserve_weight_sparsity=preserve_weight_sparsity,
                    engine=engine,
                    device_option=gc,
                )
            else:
                fc = core.CreateOperator(
                    op_type,
                    [
                        "X_q" if do_quantize else "X",
                        "W_packed"
                        if do_prepack_weight
                        else ("W_q" if do_quantize_weight else "W"),
                        "b_q" if do_quantize_weight else "b",
                    ],
                    ["Y_q" if do_dequantize else "Y"],
                    dequantize_output=not do_dequantize,
                    preserve_activation_sparsity=preserve_activation_sparsity,
                    preserve_weight_sparsity=preserve_weight_sparsity,
                    engine=engine,
                    device_option=gc,
                )
            if do_quantize_weight or do_prepack_weight:
                # When quantized weight is provided, we can't rescale the
                # output dynamically by looking at the range of output of each
                # batch, so here we provide the range of output observed from
                # fp32 reference implementation
                dnnlowp_utils.add_quantization_param_args(
                    fc, outputs[0][0], preserve_activation_sparsity
                )

            net.Proto().op.extend([fc])
            if fuse_relu and "DNNLOWP" not in engine:
                net.Relu(["Y"], "Y")

            if do_dequantize:
                dequantize = core.CreateOperator(
                    "Dequantize", ["Y_q"], ["Y"], engine=engine, device_option=gc
                )
                net.Proto().op.extend([dequantize])

            if use_input_qparam and do_dequantize and op_type != "FC":
                ref_output = outputs[0][0]
                ref_output_min = 0 if ref_output.size == 0 else ref_output.min()
                ref_output_max = 0 if ref_output.size == 0 else ref_output.max()

                q_param = dnnlowp_utils.choose_quantization_params(
                    ref_output_min, ref_output_max, preserve_activation_sparsity
                )
                run_conv_or_fc(
                    self,
                    init_net,
                    net,
                    X,
                    W,
                    b,
                    op_type,
                    engine,
                    None,
                    gc,
                    outputs,
                    q_param.scale,
                    q_param.zero_point,
                )
            else:
                run_conv_or_fc(
                    self, init_net, net, X, W, b, op_type, engine, None, gc, outputs
                )

            if output_packed_bias and do_prepack_weight and do_dequantize:
                bias_int32 = self.ws.blobs["B_q32"].fetch()
                if do_quantize_weight:
                    np.testing.assert_equal(
                        bias_int32[0], np.round(b / (x_q_param.scale * w_q_param.scale))
                    )
                np.testing.assert_equal(bias_int32[0].dtype, np.int32)

            shapes, types = workspace.InferShapesAndTypes(
                [init_net, net],
                blob_dimensions={
                    "X": [batch_size, input_channels],
                    "W": [output_channels, input_channels],
                    "b": [output_channels],
                    "quant_param": [1],
                },
                blob_types={
                    "X": core.DataType.FLOAT,
                    "W": core.DataType.FLOAT,
                    "b": core.DataType.FLOAT,
                    "quant_param": core.DataType.FLOAT,
                },
            )
            assert (
                "Y" in shapes and "Y" in types
            ), "Failed to infer the shape or type of Y"
            self.assertEqual(shapes["Y"], [batch_size, output_channels])
            self.assertEqual(types["Y"], core.DataType.FLOAT)
        check_quantized_results_close(outputs, symmetric=preserve_activation_sparsity)