import torch
import torch.nn.functional as F
import torch.nn as nn
from torch.nn import Conv1d, ConvTranspose1d, AvgPool1d, Conv2d
from torch.nn.utils import weight_norm, remove_weight_norm, spectral_norm
from models.mossformer2_sr.utils import init_weights, get_padding
from models.mossformer2_sr.mossformer2 import MossFormer_MaskNet
from models.mossformer2_sr.snake import Snake1d
from typing import Optional, List, Union, Dict, Tuple
from models.mossformer2_sr.env import AttrDict
import typing
from torchaudio.transforms import Spectrogram, Resample

LRELU_SLOPE = 0.1


class ResBlock1(torch.nn.Module):
    def __init__(self, h, channels, kernel_size=3, dilation=(1, 3, 5)):
        super(ResBlock1, self).__init__()
        self.h = h
        self.convs1 = nn.ModuleList([
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=dilation[0],
                               padding=get_padding(kernel_size, dilation[0]))),
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=dilation[1],
                               padding=get_padding(kernel_size, dilation[1]))),
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=dilation[2],
                               padding=get_padding(kernel_size, dilation[2])))
            #Snake1d(channels)
        ])        
        self.convs1.apply(init_weights)
        self.convs1_activates = nn.ModuleList([
             Snake1d(channels),
             Snake1d(channels),
             Snake1d(channels)
        ])
        self.convs2 = nn.ModuleList([
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=1,
                               padding=get_padding(kernel_size, 1))),
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=1,
                               padding=get_padding(kernel_size, 1))),
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=1,
                               padding=get_padding(kernel_size, 1)))
            #Snake1d(channels)
        ])
        self.convs2.apply(init_weights)
        #self.convs2_activate = Snake1d(channels)
        self.convs2_activates = nn.ModuleList([
             Snake1d(channels),
             Snake1d(channels),
             Snake1d(channels)
        ])

    def forward(self, x):
        for c1, c2, act1, act2 in zip(self.convs1, self.convs2, self.convs1_activates, self.convs2_activates):
            #xt = F.leaky_relu(x, LRELU_SLOPE)
            #print(f'xt: {xt.shape}')
            xt = act1(x)
            xt = c1(xt)
            #xt = F.leaky_relu(xt, LRELU_SLOPE)
            xt = act2(xt)
            xt = c2(xt)
            x = xt + x
        return x

    def remove_weight_norm(self):
        for l in self.convs1:
            remove_weight_norm(l)
        for l in self.convs2:
            remove_weight_norm(l)


class ResBlock2(torch.nn.Module):
    def __init__(self, h, channels, kernel_size=3, dilation=(1, 3)):
        super(ResBlock2, self).__init__()
        self.h = h
        self.convs = nn.ModuleList([
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=dilation[0],
                               padding=get_padding(kernel_size, dilation[0]))),
            weight_norm(Conv1d(channels, channels, kernel_size, 1, dilation=dilation[1],
                               padding=get_padding(kernel_size, dilation[1])))
            #Snake1d(channels)
        ])
        self.convs.apply(init_weights)
        #self.convs_activate = Snake1d(channels)
        self.convs_activates = nn.ModuleList([
             Snake1d(channels),
             Snake1d(channels)
        ])
    def forward(self, x):
        for c, act in zip(self.convs, self.convs_activates):
            #xt = F.leaky_relu(x, LRELU_SLOPE)
            xt = act(x)
            xt = c(xt)
            x = xt + x
        return x

    def remove_weight_norm(self):
        for l in self.convs:
            remove_weight_norm(l)


class Generator(torch.nn.Module):
    def __init__(self, h):
        super(Generator, self).__init__()
        self.h = h
        self.num_kernels = len(h.resblock_kernel_sizes)
        self.num_upsamples = len(h.upsample_rates)
        self.conv_pre = weight_norm(Conv1d(80, h.upsample_initial_channel, 7, 1, padding=3))
        resblock = ResBlock1 if h.resblock == '1' else ResBlock2

        self.ups = nn.ModuleList()
        self.snakes = nn.ModuleList()
        for i, (u, k) in enumerate(zip(h.upsample_rates, h.upsample_kernel_sizes)):
            self.snakes.append(Snake1d(h.upsample_initial_channel//(2**i)))
            self.ups.append(weight_norm(
                ConvTranspose1d(h.upsample_initial_channel//(2**i), h.upsample_initial_channel//(2**(i+1)),
                                k, u, padding=(k-u)//2)))

        self.resblocks = nn.ModuleList()
        for i in range(len(self.ups)):
            ch = h.upsample_initial_channel//(2**(i+1))
            for j, (k, d) in enumerate(zip(h.resblock_kernel_sizes, h.resblock_dilation_sizes)):
                self.resblocks.append(resblock(h, ch, k, d))

        self.snake_post = Snake1d(ch)
        self.conv_post = weight_norm(Conv1d(ch, 1, 7, 1, padding=3))
        self.ups.apply(init_weights)
        self.conv_post.apply(init_weights)
    def forward(self, x):
        x = self.conv_pre(x)
        for i in range(self.num_upsamples):
            #x = F.leaky_relu(x, LRELU_SLOPE)
            #print(f'x {i}: {x.shape}')
            x = self.snakes[i](x)
            x = self.ups[i](x)
            xs = None
            for j in range(self.num_kernels):
                if xs is None:
                    xs = self.resblocks[i*self.num_kernels+j](x)
                else:
                    xs += self.resblocks[i*self.num_kernels+j](x)
            x = xs / self.num_kernels
        #x = F.leaky_relu(x)
        x = self.snake_post(x)
        x = self.conv_post(x)
        x = torch.tanh(x)

        return x

    def remove_weight_norm(self):
        #print('Removing weight norm...')
        for l in self.ups:
            remove_weight_norm(l)
        for l in self.resblocks:
            l.remove_weight_norm()
        remove_weight_norm(self.conv_pre)
        remove_weight_norm(self.conv_post)


class DiscriminatorP(torch.nn.Module):
    def __init__(self, period, kernel_size=5, stride=3, use_spectral_norm=False):
        super(DiscriminatorP, self).__init__()
        self.period = period
        norm_f = weight_norm if use_spectral_norm == False else spectral_norm
        self.convs = nn.ModuleList([
            norm_f(Conv2d(1, 32, (kernel_size, 1), (stride, 1), padding=(get_padding(5, 1), 0))),
            norm_f(Conv2d(32, 128, (kernel_size, 1), (stride, 1), padding=(get_padding(5, 1), 0))),
            norm_f(Conv2d(128, 512, (kernel_size, 1), (stride, 1), padding=(get_padding(5, 1), 0))),
            norm_f(Conv2d(512, 1024, (kernel_size, 1), (stride, 1), padding=(get_padding(5, 1), 0))),
            norm_f(Conv2d(1024, 1024, (kernel_size, 1), 1, padding=(2, 0))),
        ])
        self.conv_post = norm_f(Conv2d(1024, 1, (3, 1), 1, padding=(1, 0)))

    def forward(self, x):
        fmap = []

        # 1d to 2d
        b, c, t = x.shape
        if t % self.period != 0: # pad first
            n_pad = self.period - (t % self.period)
            x = F.pad(x, (0, n_pad), "reflect")
            t = t + n_pad
        x = x.view(b, c, t // self.period, self.period)

        for l in self.convs:
            x = l(x)
            x = F.leaky_relu(x, LRELU_SLOPE)
            fmap.append(x)
        x = self.conv_post(x)
        fmap.append(x)
        x = torch.flatten(x, 1, -1)

        return x, fmap


class MultiPeriodDiscriminator(torch.nn.Module):
    def __init__(self):
        super(MultiPeriodDiscriminator, self).__init__()
        self.discriminators = nn.ModuleList([
            DiscriminatorP(2),
            DiscriminatorP(3),
            DiscriminatorP(5),
            DiscriminatorP(7),
            DiscriminatorP(11),
        ])

    def forward(self, y, y_hat):
        y_d_rs = []
        y_d_gs = []
        fmap_rs = []
        fmap_gs = []
        for i, d in enumerate(self.discriminators):
            y_d_r, fmap_r = d(y)
            y_d_g, fmap_g = d(y_hat)
            y_d_rs.append(y_d_r)
            fmap_rs.append(fmap_r)
            y_d_gs.append(y_d_g)
            fmap_gs.append(fmap_g)

        return y_d_rs, y_d_gs, fmap_rs, fmap_gs


class DiscriminatorS(torch.nn.Module):
    def __init__(self, use_spectral_norm=False):
        super(DiscriminatorS, self).__init__()
        norm_f = weight_norm if use_spectral_norm == False else spectral_norm
        self.convs = nn.ModuleList([
            norm_f(Conv1d(1, 128, 15, 1, padding=7)),
            norm_f(Conv1d(128, 128, 41, 2, groups=4, padding=20)),
            norm_f(Conv1d(128, 256, 41, 2, groups=16, padding=20)),
            norm_f(Conv1d(256, 512, 41, 4, groups=16, padding=20)),
            norm_f(Conv1d(512, 1024, 41, 4, groups=16, padding=20)),
            norm_f(Conv1d(1024, 1024, 41, 1, groups=16, padding=20)),
            norm_f(Conv1d(1024, 1024, 5, 1, padding=2)),
        ])
        self.conv_post = norm_f(Conv1d(1024, 1, 3, 1, padding=1))

    def forward(self, x):
        fmap = []
        for l in self.convs:
            x = l(x)
            x = F.leaky_relu(x, LRELU_SLOPE)
            fmap.append(x)
        x = self.conv_post(x)
        fmap.append(x)
        x = torch.flatten(x, 1, -1)

        return x, fmap


class MultiScaleDiscriminator(torch.nn.Module):
    def __init__(self):
        super(MultiScaleDiscriminator, self).__init__()
        self.discriminators = nn.ModuleList([
            DiscriminatorS(use_spectral_norm=True),
            DiscriminatorS(),
            DiscriminatorS(),
        ])
        self.meanpools = nn.ModuleList([
            AvgPool1d(4, 2, padding=2),
            AvgPool1d(4, 2, padding=2)
        ])

    def forward(self, y, y_hat):
        y_d_rs = []
        y_d_gs = []
        fmap_rs = []
        fmap_gs = []
        for i, d in enumerate(self.discriminators):
            if i != 0:
                y = self.meanpools[i-1](y)
                y_hat = self.meanpools[i-1](y_hat)
            y_d_r, fmap_r = d(y)
            y_d_g, fmap_g = d(y_hat)
            y_d_rs.append(y_d_r)
            fmap_rs.append(fmap_r)
            y_d_gs.append(y_d_g)
            fmap_gs.append(fmap_g)

        return y_d_rs, y_d_gs, fmap_rs, fmap_gs


# Method based on descript-audio-codec: https://github.com/descriptinc/descript-audio-codec
# Modified code adapted from https://github.com/gemelo-ai/vocos under the MIT license.
#   LICENSE is in incl_licenses directory.
class DiscriminatorB(nn.Module):
    def __init__(
        self,
        window_length: int,
        channels: int = 32,
        hop_factor: float = 0.25,
        bands: Tuple[Tuple[float, float], ...] = (
            (0.0, 0.1),
            (0.1, 0.25),
            (0.25, 0.5),
            (0.5, 0.75),
            (0.75, 1.0),
        ),
    ):
        super().__init__()
        self.window_length = window_length
        self.hop_factor = hop_factor
        self.spec_fn = Spectrogram(
            n_fft=window_length,
            hop_length=int(window_length * hop_factor),
            win_length=window_length,
            power=None,
        )
        n_fft = window_length // 2 + 1
        bands = [(int(b[0] * n_fft), int(b[1] * n_fft)) for b in bands]
        self.bands = bands
        convs = lambda: nn.ModuleList(
            [
                weight_norm(nn.Conv2d(2, channels, (3, 9), (1, 1), padding=(1, 4))),
                weight_norm(
                    nn.Conv2d(channels, channels, (3, 9), (1, 2), padding=(1, 4))
                ),
                weight_norm(
                    nn.Conv2d(channels, channels, (3, 9), (1, 2), padding=(1, 4))
                ),
                weight_norm(
                    nn.Conv2d(channels, channels, (3, 9), (1, 2), padding=(1, 4))
                ),
                weight_norm(
                    nn.Conv2d(channels, channels, (3, 3), (1, 1), padding=(1, 1))
                ),
            ]
        )
        self.band_convs = nn.ModuleList([convs() for _ in range(len(self.bands))])

        self.conv_post = weight_norm(
            nn.Conv2d(channels, 1, (3, 3), (1, 1), padding=(1, 1))
        )
    def spectrogram(self, x: torch.Tensor) -> List[torch.Tensor]:
        # Remove DC offset
        x = x - x.mean(dim=-1, keepdims=True)
        # Peak normalize the volume of input audio
        x = 0.8 * x / (x.abs().max(dim=-1, keepdim=True)[0] + 1e-9)
        x = self.spec_fn(x)
        x = torch.view_as_real(x)
        x = x.permute(0, 3, 2, 1)  # [B, F, T, C] -> [B, C, T, F]
        # Split into bands
        x_bands = [x[..., b[0] : b[1]] for b in self.bands]
        return x_bands

    def forward(self, x: torch.Tensor) -> Tuple[torch.Tensor, List[torch.Tensor]]:
        x_bands = self.spectrogram(x.squeeze(1))
        fmap = []
        x = []

        for band, stack in zip(x_bands, self.band_convs):
            for i, layer in enumerate(stack):
                band = layer(band)
                band = torch.nn.functional.leaky_relu(band, 0.1)
                if i > 0:
                    fmap.append(band)
            x.append(band)

        x = torch.cat(x, dim=-1)
        x = self.conv_post(x)
        fmap.append(x)

        return x, fmap

# Method based on descript-audio-codec: https://github.com/descriptinc/descript-audio-codec
# Modified code adapted from https://github.com/gemelo-ai/vocos under the MIT license.
#   LICENSE is in incl_licenses directory.
class MultiBandDiscriminator(nn.Module):
    def __init__(
        self,
        h,
    ):
        """
        Multi-band multi-scale STFT discriminator, with the architecture based on https://github.com/descriptinc/descript-audio-codec.
        and the modified code adapted from https://github.com/gemelo-ai/vocos.
        """
        super().__init__()
        # fft_sizes (list[int]): Tuple of window lengths for FFT. Defaults to [2048, 1024, 512] if not set in h.
        self.fft_sizes = h.get("mbd_fft_sizes", [2048, 1024, 512])
        self.discriminators = nn.ModuleList(
            [DiscriminatorB(window_length=w) for w in self.fft_sizes]
        )

    def forward(self, y: torch.Tensor, y_hat: torch.Tensor) -> Tuple[
        List[torch.Tensor],
        List[torch.Tensor],
        List[List[torch.Tensor]],
        List[List[torch.Tensor]],
    ]:

        y_d_rs = []
        y_d_gs = []
        fmap_rs = []
        fmap_gs = []

        for d in self.discriminators:
            y_d_r, fmap_r = d(x=y)
            y_d_g, fmap_g = d(x=y_hat)
            y_d_rs.append(y_d_r)
            fmap_rs.append(fmap_r)
            y_d_gs.append(y_d_g)
            fmap_gs.append(fmap_g)

        return y_d_rs, y_d_gs, fmap_rs, fmap_gs

def feature_loss(fmap_r, fmap_g):
    loss = 0
    for dr, dg in zip(fmap_r, fmap_g):
        for rl, gl in zip(dr, dg):
            loss += torch.mean(torch.abs(rl - gl))

    return loss*2


def discriminator_loss(disc_real_outputs, disc_generated_outputs):
    loss = 0
    r_losses = []
    g_losses = []
    for dr, dg in zip(disc_real_outputs, disc_generated_outputs):
        r_loss = torch.mean((1-dr)**2)
        g_loss = torch.mean(dg**2)
        loss += (r_loss + g_loss)
        r_losses.append(r_loss.item())
        g_losses.append(g_loss.item())

    return loss, r_losses, g_losses


def generator_loss(disc_outputs):
    loss = 0
    gen_losses = []
    for dg in disc_outputs:
        l = torch.mean((1-dg)**2)
        gen_losses.append(l)
        loss += l

    return loss, gen_losses

class Mossformer(nn.Module):

    def __init__(self):
        super(Mossformer, self).__init__()
        self.mossformer = MossFormer_MaskNet(in_channels=80, out_channels=512, out_channels_final=80)

    def forward(self, input):
        out = self.mossformer(input)
        return out