import functools
import torch.nn as nn


from ..basic import ActNorm, CircularConv2d


class NLayerDiscriminator(nn.Module):
    """Defines a PatchGAN discriminator as in Pix2Pix
        --> see https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/blob/master/models/networks.py
    """
    def __init__(self, input_nc=1, output_nc=1, ndf=64, n_layers=3, use_actnorm=False):
        """Construct a PatchGAN discriminator
        Parameters:
            input_nc (int)  -- the number of channels in input images
            ndf (int)       -- the number of filters in the last conv layer
            n_layers (int)  -- the number of conv layers in the discriminator
            norm_layer      -- normalization layer
        """
        super(NLayerDiscriminator, self).__init__()
        if not use_actnorm:
            norm_layer = nn.BatchNorm2d
        else:
            norm_layer = ActNorm
        if type(norm_layer) == functools.partial:  # no need to use bias as BatchNorm2d has affine parameters
            use_bias = norm_layer.func != nn.BatchNorm2d
        else:
            use_bias = norm_layer != nn.BatchNorm2d

        kw = 4
        padw = 1
        sequence = [nn.Conv2d(input_nc, ndf, kernel_size=kw, stride=2, padding=padw), nn.LeakyReLU(0.2, True)]
        nf_mult = 1
        for n in range(1, n_layers):  # gradually increase the number of filters
            nf_mult_prev = nf_mult
            nf_mult = min(2 ** n, 8)
            sequence += [
                nn.Conv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=2, padding=padw, bias=use_bias),
                norm_layer(ndf * nf_mult),
                nn.LeakyReLU(0.2, True)
            ]

        nf_mult_prev = nf_mult
        nf_mult = min(2 ** n_layers, 8)
        sequence += [
            nn.Conv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=1, padding=padw, bias=use_bias),
            norm_layer(ndf * nf_mult),
            nn.LeakyReLU(0.2, True)
        ]

        sequence += [
            nn.Conv2d(ndf * nf_mult, output_nc, kernel_size=kw, stride=1, padding=padw)]  # output 1 channel prediction map
        self.main = nn.Sequential(*sequence)

    def forward(self, input):
        """Standard forward."""
        return self.main(input)


class LiDARNLayerDiscriminator(nn.Module):
    """Modified PatchGAN discriminator from Pix2Pix
        --> see https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/blob/master/models/networks.py
    """
    def __init__(self, input_nc=1, output_nc=1, ndf=64, n_layers=3, use_actnorm=False):
        """Construct a PatchGAN discriminator
        Parameters:
            input_nc (int)  -- the number of channels in input images
            ndf (int)       -- the number of filters in the last conv layer
            n_layers (int)  -- the number of conv layers in the discriminator
            norm_layer      -- normalization layer
        """
        super(LiDARNLayerDiscriminator, self).__init__()
        if not use_actnorm:
            norm_layer = nn.BatchNorm2d
        else:
            norm_layer = ActNorm
        if type(norm_layer) == functools.partial:  # no need to use bias as BatchNorm2d has affine parameters
            use_bias = norm_layer.func != nn.BatchNorm2d
        else:
            use_bias = norm_layer != nn.BatchNorm2d

        kw = (4, 4)
        sequence = [CircularConv2d(input_nc, ndf, kernel_size=kw, stride=(1, 2), padding=(1, 2, 1, 2)), nn.LeakyReLU(0.2, True)]
        nf_mult = 1
        nf_mult_prev = 1
        for n in range(1, n_layers):  # gradually increase the number of filters
            nf_mult_prev = nf_mult
            nf_mult = min(2 ** n, 8)
            sequence += [
                CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=(1, 2), bias=use_bias, padding=(1, 2, 1, 2)),
                norm_layer(ndf * nf_mult),
                nn.LeakyReLU(0.2, True)
            ]

        nf_mult_prev = nf_mult
        nf_mult = min(2 ** n_layers, 8)
        sequence += [
            CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=1, bias=use_bias, padding=(1, 2, 1, 2)),
            norm_layer(ndf * nf_mult),
            nn.LeakyReLU(0.2, True)
        ]

        sequence += [
            CircularConv2d(ndf * nf_mult, output_nc, kernel_size=kw, stride=1, padding=(1, 2, 1, 2))]  # output 1 channel prediction map
        self.main = nn.Sequential(*sequence)

    def forward(self, input):
        """Standard forward."""
        return self.main(input)


class LiDARNLayerDiscriminatorV2(nn.Module):
    """Modified PatchGAN discriminator from Pix2Pix (larger receptive field)
        --> see https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/blob/master/models/networks.py
    """
    def __init__(self, input_nc=1, output_nc=1, ndf=64, n_layers=3, use_actnorm=False):
        """Construct a PatchGAN discriminator
        Parameters:
            input_nc (int)  -- the number of channels in input images
            ndf (int)       -- the number of filters in the last conv layer
            n_layers (int)  -- the number of conv layers in the discriminator
            norm_layer      -- normalization layer
        """
        super(LiDARNLayerDiscriminatorV2, self).__init__()
        if not use_actnorm:
            norm_layer = nn.BatchNorm2d
        else:
            norm_layer = ActNorm
        if type(norm_layer) == functools.partial:  # no need to use bias as BatchNorm2d has affine parameters
            use_bias = norm_layer.func != nn.BatchNorm2d
        else:
            use_bias = norm_layer != nn.BatchNorm2d

        kw = (4, 4)
        sequence = [CircularConv2d(input_nc, ndf, kernel_size=kw, stride=(1, 2), padding=(1, 2, 1, 2)), nn.LeakyReLU(0.2, True),
                    CircularConv2d(ndf, ndf, kernel_size=kw, stride=(1, 2), padding=(1, 2, 1, 2)), nn.LeakyReLU(0.2, True)]
        nf_mult = 1
        nf_mult_prev = 1
        for n in range(1, n_layers):  # gradually increase the number of filters
            nf_mult_prev = nf_mult
            nf_mult = min(2 ** n, 8)
            sequence += [
                CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=(2, 2), bias=use_bias, padding=(1, 2, 1, 2)),
                norm_layer(ndf * nf_mult),
                nn.LeakyReLU(0.2, True)
            ]

        nf_mult_prev = nf_mult
        nf_mult = min(2 ** n_layers, 8)
        sequence += [
            CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=1, bias=use_bias, padding=(1, 2, 1, 2)),
            norm_layer(ndf * nf_mult),
            nn.LeakyReLU(0.2, True)
        ]

        sequence += [
            CircularConv2d(ndf * nf_mult, output_nc, kernel_size=kw, stride=1, padding=(1, 2, 1, 2))]  # output 1 channel prediction map
        self.main = nn.Sequential(*sequence)

    def forward(self, input):
        """Standard forward."""
        return self.main(input)


class LiDARNLayerDiscriminatorV3(nn.Module):
    """Modified PatchGAN discriminator from Pix2Pix (larger receptive field)
        --> see https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/blob/master/models/networks.py
    """
    def __init__(self, input_nc=1, output_nc=1, ndf=64, n_layers=3, use_actnorm=False):
        """Construct a PatchGAN discriminator
        Parameters:
            input_nc (int)  -- the number of channels in input images
            ndf (int)       -- the number of filters in the last conv layer
            n_layers (int)  -- the number of conv layers in the discriminator
            norm_layer      -- normalization layer
        """
        super(LiDARNLayerDiscriminatorV3, self).__init__()
        if not use_actnorm:
            norm_layer = nn.BatchNorm2d
        else:
            norm_layer = ActNorm
        if type(norm_layer) == functools.partial:  # no need to use bias as BatchNorm2d has affine parameters
            use_bias = norm_layer.func != nn.BatchNorm2d
        else:
            use_bias = norm_layer != nn.BatchNorm2d

        kw = (4, 4)
        sequence = [CircularConv2d(input_nc, ndf, kernel_size=(1, 4), stride=(1, 1), padding=(1, 2, 1, 2)), nn.LeakyReLU(0.2, True),
                    CircularConv2d(ndf, ndf, kernel_size=kw, stride=(2, 2), padding=(1, 2, 1, 2)), nn.LeakyReLU(0.2, True)]
        nf_mult = 1
        nf_mult_prev = 1
        for n in range(1, n_layers):  # gradually increase the number of filters
            nf_mult_prev = nf_mult
            nf_mult = min(2 ** n, 8)
            sequence += [
                CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=(2, 2), bias=use_bias, padding=(1, 2, 1, 2)),
                norm_layer(ndf * nf_mult),
                nn.LeakyReLU(0.2, True)
            ]

        nf_mult_prev = nf_mult
        nf_mult = min(2 ** n_layers, 8)
        sequence += [
            CircularConv2d(ndf * nf_mult_prev, ndf * nf_mult, kernel_size=kw, stride=1, bias=use_bias, padding=(1, 2, 1, 2)),
            norm_layer(ndf * nf_mult),
            nn.LeakyReLU(0.2, True)
        ]

        sequence += [
            CircularConv2d(ndf * nf_mult, output_nc, kernel_size=kw, stride=1, padding=(1, 2, 1, 2))]  # output 1 channel prediction map
        self.main = nn.Sequential(*sequence)

    def forward(self, input):
        """Standard forward."""
        import pdb; pdb.set_trace()
        return self.main(input)