import torch
import torch.nn as nn
import torch.ao.nn.intrinsic as nni
import torch.nn.functional as F
import torch.ao.nn.quantized.reference as nnqr
from ._common_operator_config_utils import (
    _get_conv_configs,
    _get_linear_configs,
    _get_binary_op_configs,
    _get_bn_configs,
    _get_cat_config,
    _get_default_op_configs,
    _get_embedding_op_configs,
    _get_fixed_qparams_op_configs,
    _get_ln_configs,
    _get_rnn_op_configs,
    _get_share_qparams_op_configs,
)
from .backend_config import (
    BackendPatternConfig,
    BackendConfig,
    DTypeConfig,
    ObservationType,
)
from ..fuser_method_mappings import (
    _sequential_wrapper2,
)
import operator
from torch.ao.quantization.utils import MatchAllNode
import itertools

# ===================
# |  DTYPE CONFIGS  |
# ===================

onednn_weighted_op_int8_dtype_config = DTypeConfig(
    input_dtype=torch.quint8,
    output_dtype=torch.quint8,
    weight_dtype=torch.qint8,
    bias_dtype=torch.float,
)

onednn_op_quint8_dtype_config = DTypeConfig(
    input_dtype=torch.quint8,
    output_dtype=torch.quint8,
)

onednn_dynamic_int8_dtype_config = DTypeConfig(
    input_dtype=torch.quint8,
    output_dtype=torch.float,
    weight_dtype=torch.qint8,
    bias_dtype=torch.float,
    is_dynamic=True,
)

onednn_weight_only_qint8_dtype_config = DTypeConfig(
    input_dtype=torch.float,
    output_dtype=torch.float,
    weight_dtype=torch.qint8,
)

onednn_input_output_only_quint8_dtype_config = DTypeConfig(
    input_dtype=torch.quint8,
    output_dtype=torch.quint8,
    weight_dtype=torch.float,
    bias_dtype=torch.float,
)

# ===================
# |  FUSER METHODS  |
# ===================

def _fuse_linear_bn_leaky_relu(is_qat, linear, bn, leaky_relu):
    r"""Given the linear, bn and leaky_relu modules, fuses them and returns the fused module
    Args:
        is_qat: a flag for whether we are using quantization aware training fusion
                or post training quantization fusion
        linear: Module instance of type Linear
        bn: BatchNorm1d instance that needs to be fused with the linear layer
        leaky_relu: LeakyReLU instance that needs to be fused with the linear layer
    Examples::
        >>> # xdoctest: +SKIP(failing)
        >>> m1 = nn.Linear(20, 10)
        >>> b1 = nn.BatchNorm1d(10)
        >>> lr = nn.LeakyReLU(0.01)
        >>> m2 = _fuse_linear_bn_leaky_relu(m1, b1, lr)
    """
    assert(linear.training == bn.training and bn.training == leaky_relu.training),\
        "Linear, BN and LeakyReLU all must be in the same mode (train or eval)."

    if is_qat:
        raise NotImplementedError("Cannot fuse train modules: {}".format((linear, bn, leaky_relu)))
    else:
        map_to_fused_module_eval = {
            nn.Linear: nni.LinearLeakyReLU,
        }
        fused_module = map_to_fused_module_eval.get(type(linear), None)
        if fused_module is not None:
            fused_linear = nn.utils.fusion.fuse_linear_bn_eval(linear, bn)
            fm = fused_module(fused_linear, leaky_relu)
            return fm
        else:
            raise NotImplementedError("Cannot fuse eval modules: {}".format((linear, bn, leaky_relu)))

# ======================
# |  CONFIGS FOR CONV  |
# ======================
observation_type = ObservationType.OUTPUT_USE_DIFFERENT_OBSERVER_AS_INPUT

conv_dtype_configs = [onednn_weighted_op_int8_dtype_config]
conv_configs = _get_conv_configs(conv_dtype_configs)

# (1) Conv2d + Add

# conv2d   Y
#   \   /
#    add

# include:
# conv2d conv2d
#   \   /
#    add

def _fuse_conv_add_left(is_qat, add, conv, _):
    return nni.ConvAdd2d(conv, add)

def _conv_add_root_node_getter_left(pattern):
    _, conv, _ = pattern
    return conv

def _conv_add_extra_inputs_getter_left(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    _, conv, extra_input = pattern
    return [extra_input]

# conv2d
#  \
#  bn   Y
#   \   /
#    add

def _fuse_conv_bn_add_left(is_qat, add, bn_conv, _):
    bn, conv = bn_conv
    if is_qat:
        raise NotImplementedError("Cannot fuse train modules: {}".format((conv, bn, add)))
    else:
        fused_conv = nn.utils.fusion.fuse_conv_bn_eval(conv, bn)
        return nni.ConvAdd2d(fused_conv, add)

def _conv_bn_add_root_node_getter_left(add_pattern):
    _, bn_conv, _ = add_pattern
    bn, conv = bn_conv
    return conv

def _conv_bn_add_extra_inputs_getter_left(add_pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    _, bn_conv, extra_input = add_pattern
    bn, conv = bn_conv
    return [extra_input]

conv_add_left_optioins = itertools.product(
    [True, False],  # with_bn
    [torch.add, operator.add],  # add_op
)

for with_bn, add_op in conv_add_left_optioins:
    if with_bn:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((add_op, (nn.BatchNorm2d, nn.Conv2d), MatchAllNode))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_bn_add_left)
                ._set_root_node_getter(_conv_bn_add_root_node_getter_left)
                ._set_extra_inputs_getter(_conv_bn_add_extra_inputs_getter_left)
                .set_fused_module(nni.ConvAdd2d))
    else:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((add_op, nn.Conv2d, MatchAllNode))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_add_left)
                ._set_root_node_getter(_conv_add_root_node_getter_left)
                ._set_extra_inputs_getter(_conv_add_extra_inputs_getter_left)
                .set_fused_module(nni.ConvAdd2d))

#  Y   conv2d
#   \   /
#    add

def _fuse_conv_add_right(is_qat, add, _, conv):
    return nni.ConvAdd2d(conv, add)

def _conv_add_root_node_getter_right(pattern):
    add, _, conv = pattern
    return conv

def _conv_add_extra_inputs_getter_right(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    _, extra_input, conv = pattern
    return [extra_input]

#      conv2d
#        /
#  Y    bn
#   \   /
#    add

def _fuse_conv_bn_add_right(is_qat, add, _, bn_conv):
    bn, conv = bn_conv
    if is_qat:
        raise NotImplementedError("Cannot fuse train modules: {}".format((conv, bn, add)))
    else:
        fused_conv = nn.utils.fusion.fuse_conv_bn_eval(conv, bn)
        return nni.ConvAdd2d(fused_conv, add)

def _conv_bn_add_root_node_getter_right(pattern):
    add, _, bn_conv = pattern
    bn, conv = bn_conv
    return conv

def _conv_bn_add_extra_inputs_getter_right(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    _, extra_input, bn_conv = pattern
    bn, conv = bn_conv
    return [extra_input]

conv_add_optioins = itertools.product(
    [True, False],  # with_bn
    [torch.add, operator.add],  # add_op
)

for with_bn, add_op in conv_add_optioins:
    if with_bn:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((add_op, MatchAllNode, (nn.BatchNorm2d, nn.Conv2d)))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_bn_add_right)
                ._set_root_node_getter(_conv_bn_add_root_node_getter_right)
                ._set_extra_inputs_getter(_conv_bn_add_extra_inputs_getter_right)
                .set_fused_module(nni.ConvAdd2d))
    else:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((add_op, MatchAllNode, nn.Conv2d))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_add_right)
                ._set_root_node_getter(_conv_add_root_node_getter_right)
                ._set_extra_inputs_getter(_conv_add_extra_inputs_getter_right)
                .set_fused_module(nni.ConvAdd2d))

conv_configs.append(
    BackendPatternConfig(nni.ConvAdd2d)
        .set_observation_type(observation_type)  # noqa: E131
        .set_dtype_configs(conv_dtype_configs)
        .set_root_module(nn.Conv2d)
        .set_reference_quantized_module(nnqr.Conv2d))

# (2) Conv2d + Add + Relu

# conv2d Y
#   \   /
#    add
#     \
#     relu

def _fuse_conv_add_relu_left(is_qat, relu, add_pattern):
    add, conv, _ = add_pattern
    return nni.ConvAddReLU2d(conv, add, relu)

def _conv_add_relu_root_node_getter_left(pattern):
    relu, add_pattern = pattern
    _, conv, _ = add_pattern
    return conv

def _conv_add_relu_extra_inputs_getter_left(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    relu, add_pattern = pattern
    _, conv, extra_input = add_pattern
    return [extra_input]

# conv2d
#  \
#  bn   Y
#   \   /
#    add
#     \
#     relu

def _fuse_conv_bn_add_relu_left(is_qat, relu, add_pattern):
    add, bn_conv, _ = add_pattern
    bn, conv = bn_conv
    if is_qat:
        raise NotImplementedError("Cannot fuse train modules: {}".format((conv, bn, add, relu)))
    else:
        fused_conv = nn.utils.fusion.fuse_conv_bn_eval(conv, bn)
        return nni.ConvAddReLU2d(fused_conv, add, relu)

def _conv_bn_add_relu_root_node_getter_left(pattern):
    relu, add_pattern = pattern
    _, bn_conv, _ = add_pattern
    bn, conv = bn_conv
    return conv

def _conv_bn_add_relu_extra_inputs_getter_left(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    relu, add_pattern = pattern
    _, bn_conv, extra_input = add_pattern
    bn, conv = bn_conv
    return [extra_input]

conv_add_relu_left_optioins = itertools.product(
    [True, False],  # with_bn
    [torch.add, operator.add],  # add_op
)

for with_bn, add_op in conv_add_relu_left_optioins:
    if with_bn:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((nn.ReLU, (add_op, (nn.BatchNorm2d, nn.Conv2d), MatchAllNode)))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_bn_add_relu_left)
                ._set_root_node_getter(_conv_bn_add_relu_root_node_getter_left)
                ._set_extra_inputs_getter(_conv_bn_add_relu_extra_inputs_getter_left)
                .set_fused_module(nni.ConvAddReLU2d))
    else:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((nn.ReLU, (add_op, nn.Conv2d, MatchAllNode)))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_add_relu_left)
                ._set_root_node_getter(_conv_add_relu_root_node_getter_left)
                ._set_extra_inputs_getter(_conv_add_relu_extra_inputs_getter_left)
                .set_fused_module(nni.ConvAddReLU2d))

#  Y   conv2d
#   \   /
#    add
#     \
#     relu

def _fuse_conv_add_relu_right(is_qat, relu, add_pattern):
    add, _, conv = add_pattern
    return nni.ConvAddReLU2d(conv, add, relu)

def _conv_add_relu_root_node_getter_right(pattern):
    relu, add_pattern = pattern
    _, _, conv = add_pattern
    return conv

def _conv_add_relu_extra_inputs_getter_right(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    relu, add_pattern = pattern
    _, extra_input, conv = add_pattern
    return [extra_input]

#      conv2d
#        /
#  Y    bn
#   \   /
#    add
#     \
#     relu

def _fuse_conv_bn_add_relu_right(is_qat, relu, add_pattern):
    add, _, bn_conv = add_pattern
    bn, conv = bn_conv
    if is_qat:
        raise NotImplementedError("Cannot fuse train modules: {}".format((conv, bn, add, relu)))
    else:
        fused_conv = nn.utils.fusion.fuse_conv_bn_eval(conv, bn)
        return nni.ConvAddReLU2d(fused_conv, add, relu)

def _conv_bn_add_relu_root_node_getter_right(pattern):
    relu, add_pattern = pattern
    _, _, bn_conv = add_pattern
    bn, conv = bn_conv
    return conv

def _conv_bn_add_relu_extra_inputs_getter_right(pattern):
    """ get inputs pattern for extra inputs, inputs for root node
    are assumed to be copied over from root node to the fused node
    """
    relu, add_pattern = pattern
    _, extra_input, bn_conv = add_pattern
    bn, conv = bn_conv
    return [extra_input]

conv_add_relu_optioins = itertools.product(
    [True, False],  # with_bn
    [torch.add, operator.add],  # add_op
)

for with_bn, add_op in conv_add_relu_optioins:
    if with_bn:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((nn.ReLU, (add_op, MatchAllNode, (nn.BatchNorm2d, nn.Conv2d))))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_bn_add_relu_right)
                ._set_root_node_getter(_conv_bn_add_relu_root_node_getter_right)
                ._set_extra_inputs_getter(_conv_bn_add_relu_extra_inputs_getter_right)
                .set_fused_module(nni.ConvAddReLU2d))
    else:
        conv_configs.append(
            BackendPatternConfig()
                ._set_pattern_complex_format((nn.ReLU, (add_op, MatchAllNode, nn.Conv2d)))  # noqa: E131
                .set_observation_type(observation_type)
                .set_dtype_configs(conv_dtype_configs)
                .set_fuser_method(_fuse_conv_add_relu_right)
                ._set_root_node_getter(_conv_add_relu_root_node_getter_right)
                ._set_extra_inputs_getter(_conv_add_relu_extra_inputs_getter_right)
                .set_fused_module(nni.ConvAddReLU2d))

conv_configs.append(
    BackendPatternConfig(nni.ConvAddReLU2d)
        .set_observation_type(observation_type)  # noqa: E131
        .set_dtype_configs(conv_dtype_configs)
        .set_root_module(nn.Conv2d)
        .set_reference_quantized_module(nnqr.Conv2d))

# ========================
# |  CONFIGS FOR LINEAR  |
# ========================

linear_dtype_configs = [
    onednn_weighted_op_int8_dtype_config,
    onednn_dynamic_int8_dtype_config,
]
linear_configs = _get_linear_configs(linear_dtype_configs)

def _add_eltwise_fusion_configs(configs, root_module, root_op, post_module, post_op,
                                dtype_configs, fuser_method, fused_module, observation_type,
                                ref_quant_module):
    # 1 base module + op module fusion config
    configs.append(
        BackendPatternConfig((root_module, post_module))
            .set_dtype_configs(dtype_configs)  # noqa: E131
            .set_fuser_method(fuser_method)
            .set_fused_module(fused_module))
    # base module + functional post op
    configs.append(
        BackendPatternConfig((root_module, post_op))
            .set_dtype_configs(dtype_configs)  # noqa: E131
            .set_fuser_method(fuser_method)
            .set_fused_module(fused_module))

    # 2 fused module configs
    configs.append(
        BackendPatternConfig(fused_module)
            .set_observation_type(observation_type)  # noqa: E131
            .set_dtype_configs(dtype_configs)
            .set_root_module(root_module)
            .set_reference_quantized_module(ref_quant_module))

    # 3 functional base op + post op configs
    configs.append(
        BackendPatternConfig((root_op, post_module))
            .set_observation_type(observation_type)  # noqa: E131
            .set_dtype_configs(dtype_configs))
    configs.append(
        BackendPatternConfig((root_op, post_op))
            .set_observation_type(observation_type)  # noqa: E131
            .set_dtype_configs(dtype_configs))

# Configs for linear + leaky_relu fusion
_add_eltwise_fusion_configs(linear_configs, nn.Linear, F.linear,
                            nn.LeakyReLU, F.leaky_relu, linear_dtype_configs,
                            _sequential_wrapper2(nni.LinearLeakyReLU),
                            nni.LinearLeakyReLU, observation_type, nnqr.Linear)

# Configs for linear module + batchnorm + leaky_relu
linear_configs.append(
    BackendPatternConfig((nn.Linear, nn.BatchNorm1d, nn.LeakyReLU))
        .set_dtype_configs(linear_dtype_configs)  # noqa: E131
        .set_fuser_method(_fuse_linear_bn_leaky_relu)
        .set_fused_module(nni.LinearLeakyReLU))

# Configs for linear + tanh fusion
_add_eltwise_fusion_configs(linear_configs, nn.Linear, F.linear,
                            nn.Tanh, torch.tanh, linear_dtype_configs,
                            _sequential_wrapper2(nni.LinearTanh),
                            nni.LinearTanh, observation_type, nnqr.Linear)

# ===========================
# |  CONFIGS FOR OTHER OPS  |
# ===========================

binary_op_dtype_configs = [onednn_op_quint8_dtype_config]
default_op_dtype_configs = [onednn_op_quint8_dtype_config]
fixed_qparams_op_dtype_configs = [onednn_op_quint8_dtype_config]
share_qparams_op_dtype_configs = [onednn_op_quint8_dtype_config]
rnn_op_dtype_configs = [onednn_dynamic_int8_dtype_config]
embedding_op_dtype_configs = [onednn_weight_only_qint8_dtype_config]
layer_norm_op_dtype_configs = [onednn_input_output_only_quint8_dtype_config]

# =====================
# |  BACKEND CONFIGS  |
# =====================

def get_onednn_backend_config() -> BackendConfig:
    """
    Return the `BackendConfig` for PyTorch's native ONEDNN backend.
    """
    return BackendConfig("onednn") \
        .set_backend_pattern_configs(conv_configs) \
        .set_backend_pattern_configs(linear_configs) \
        .set_backend_pattern_configs(_get_binary_op_configs(binary_op_dtype_configs)) \
        .set_backend_pattern_config(_get_cat_config(default_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_default_op_configs(default_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_fixed_qparams_op_configs(fixed_qparams_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_share_qparams_op_configs(share_qparams_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_bn_configs(default_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_ln_configs(layer_norm_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_rnn_op_configs(rnn_op_dtype_configs)) \
        .set_backend_pattern_configs(_get_embedding_op_configs(embedding_op_dtype_configs))

__all__ = [
    "get_onednn_backend_config",
]
