import torch
from torch import nn
from torch.nn import functional as F
import modules.attentions as attentions
import modules.commons as commons
import modules.modules as modules

from torch.nn import Conv1d, ConvTranspose1d, AvgPool1d, Conv2d
from torch.nn.utils import weight_norm, remove_weight_norm, spectral_norm

import utils
from modules.commons import init_weights, get_padding
from vdecoder.hifigan.models import Generator
from utils import f0_to_coarse


class ResidualCouplingBlock(nn.Module):
    def __init__(self,
                 channels,
                 hidden_channels,
                 kernel_size,
                 dilation_rate,
                 n_layers,
                 n_flows=4,
                 gin_channels=0):
        super().__init__()
        self.channels = channels
        self.hidden_channels = hidden_channels
        self.kernel_size = kernel_size
        self.dilation_rate = dilation_rate
        self.n_layers = n_layers
        self.n_flows = n_flows
        self.gin_channels = gin_channels

        self.flows = nn.ModuleList()
        for i in range(n_flows):
            self.flows.append(
                modules.ResidualCouplingLayer(channels, hidden_channels, kernel_size, dilation_rate, n_layers,
                                              gin_channels=gin_channels, mean_only=True))
            self.flows.append(modules.Flip())

    def forward(self, x, x_mask, g=None, reverse=False):
        if not reverse:
            for flow in self.flows:
                x, _ = flow(x, x_mask, g=g, reverse=reverse)
        else:
            for flow in reversed(self.flows):
                x = flow(x, x_mask, g=g, reverse=reverse)
        return x


class Encoder(nn.Module):
    def __init__(self,
                 in_channels,
                 out_channels,
                 hidden_channels,
                 kernel_size,
                 dilation_rate,
                 n_layers,
                 gin_channels=0):
        super().__init__()
        self.in_channels = in_channels
        self.out_channels = out_channels
        self.hidden_channels = hidden_channels
        self.kernel_size = kernel_size
        self.dilation_rate = dilation_rate
        self.n_layers = n_layers
        self.gin_channels = gin_channels

        self.pre = nn.Conv1d(in_channels, hidden_channels, 1)
        self.enc = modules.WN(hidden_channels, kernel_size, dilation_rate, n_layers, gin_channels=gin_channels)
        self.proj = nn.Conv1d(hidden_channels, out_channels * 2, 1)

    def forward(self, x, x_lengths, g=None):
        # print(x.shape,x_lengths.shape)
        x_mask = torch.unsqueeze(commons.sequence_mask(x_lengths, x.size(2)), 1).to(x.dtype)
        x = self.pre(x) * x_mask
        x = self.enc(x, x_mask, g=g)
        stats = self.proj(x) * x_mask
        m, logs = torch.split(stats, self.out_channels, dim=1)
        z = (m + torch.randn_like(m) * torch.exp(logs)) * x_mask
        return z, m, logs, x_mask


class TextEncoder(nn.Module):
    def __init__(self,
                 out_channels,
                 hidden_channels,
                 kernel_size,
                 n_layers,
                 gin_channels=0,
                 filter_channels=None,
                 n_heads=None,
                 p_dropout=None):
        super().__init__()
        self.out_channels = out_channels
        self.hidden_channels = hidden_channels
        self.kernel_size = kernel_size
        self.n_layers = n_layers
        self.gin_channels = gin_channels
        self.proj = nn.Conv1d(hidden_channels, out_channels * 2, 1)
        self.f0_emb = nn.Embedding(256, hidden_channels)

        self.enc_ = attentions.Encoder(
            hidden_channels,
            filter_channels,
            n_heads,
            n_layers,
            kernel_size,
            p_dropout)

    def forward(self, x, x_mask, f0=None, z=None):
        x = x + self.f0_emb(f0).transpose(1, 2)
        x = self.enc_(x * x_mask, x_mask)
        stats = self.proj(x) * x_mask
        m, logs = torch.split(stats, self.out_channels, dim=1)
        z = (m + z * torch.exp(logs)) * x_mask
        return z, m, logs, x_mask


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
        self.use_spectral_norm = use_spectral_norm
        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(kernel_size, 1), 0))),
            norm_f(Conv2d(32, 128, (kernel_size, 1), (stride, 1), padding=(get_padding(kernel_size, 1), 0))),
            norm_f(Conv2d(128, 512, (kernel_size, 1), (stride, 1), padding=(get_padding(kernel_size, 1), 0))),
            norm_f(Conv2d(512, 1024, (kernel_size, 1), (stride, 1), padding=(get_padding(kernel_size, 1), 0))),
            norm_f(Conv2d(1024, 1024, (kernel_size, 1), 1, padding=(get_padding(kernel_size, 1), 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, modules.LRELU_SLOPE)
            fmap.append(x)
        x = self.conv_post(x)
        fmap.append(x)
        x = torch.flatten(x, 1, -1)

        return x, fmap


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, 16, 15, 1, padding=7)),
            norm_f(Conv1d(16, 64, 41, 4, groups=4, padding=20)),
            norm_f(Conv1d(64, 256, 41, 4, groups=16, padding=20)),
            norm_f(Conv1d(256, 1024, 41, 4, groups=64, padding=20)),
            norm_f(Conv1d(1024, 1024, 41, 4, groups=256, 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, modules.LRELU_SLOPE)
            fmap.append(x)
        x = self.conv_post(x)
        fmap.append(x)
        x = torch.flatten(x, 1, -1)

        return x, fmap


class F0Decoder(nn.Module):
    def __init__(self,
                 out_channels,
                 hidden_channels,
                 filter_channels,
                 n_heads,
                 n_layers,
                 kernel_size,
                 p_dropout,
                 spk_channels=0):
        super().__init__()
        self.out_channels = out_channels
        self.hidden_channels = hidden_channels
        self.filter_channels = filter_channels
        self.n_heads = n_heads
        self.n_layers = n_layers
        self.kernel_size = kernel_size
        self.p_dropout = p_dropout
        self.spk_channels = spk_channels

        self.prenet = nn.Conv1d(hidden_channels, hidden_channels, 3, padding=1)
        self.decoder = attentions.FFT(
            hidden_channels,
            filter_channels,
            n_heads,
            n_layers,
            kernel_size,
            p_dropout)
        self.proj = nn.Conv1d(hidden_channels, out_channels, 1)
        self.f0_prenet = nn.Conv1d(1, hidden_channels, 3, padding=1)
        self.cond = nn.Conv1d(spk_channels, hidden_channels, 1)

    def forward(self, x, norm_f0, x_mask, spk_emb=None):
        x = torch.detach(x)
        if spk_emb is not None:
            x = x + self.cond(spk_emb)
        x += self.f0_prenet(norm_f0)
        x = self.prenet(x) * x_mask
        x = self.decoder(x * x_mask, x_mask)
        x = self.proj(x) * x_mask
        return x


class SynthesizerTrn(nn.Module):
    """
  Synthesizer for Training
  """

    def __init__(self,
                 spec_channels,
                 segment_size,
                 inter_channels,
                 hidden_channels,
                 filter_channels,
                 n_heads,
                 n_layers,
                 kernel_size,
                 p_dropout,
                 resblock,
                 resblock_kernel_sizes,
                 resblock_dilation_sizes,
                 upsample_rates,
                 upsample_initial_channel,
                 upsample_kernel_sizes,
                 gin_channels,
                 ssl_dim,
                 n_speakers,
                 sampling_rate=44100,
                 **kwargs):
        super().__init__()
        self.spec_channels = spec_channels
        self.inter_channels = inter_channels
        self.hidden_channels = hidden_channels
        self.filter_channels = filter_channels
        self.n_heads = n_heads
        self.n_layers = n_layers
        self.kernel_size = kernel_size
        self.p_dropout = p_dropout
        self.resblock = resblock
        self.resblock_kernel_sizes = resblock_kernel_sizes
        self.resblock_dilation_sizes = resblock_dilation_sizes
        self.upsample_rates = upsample_rates
        self.upsample_initial_channel = upsample_initial_channel
        self.upsample_kernel_sizes = upsample_kernel_sizes
        self.segment_size = segment_size
        self.gin_channels = gin_channels
        self.ssl_dim = ssl_dim
        self.emb_g = nn.Embedding(n_speakers, gin_channels)

        self.pre = nn.Conv1d(ssl_dim, hidden_channels, kernel_size=5, padding=2)

        self.enc_p = TextEncoder(
            inter_channels,
            hidden_channels,
            filter_channels=filter_channels,
            n_heads=n_heads,
            n_layers=n_layers,
            kernel_size=kernel_size,
            p_dropout=p_dropout
        )
        hps = {
            "sampling_rate": sampling_rate,
            "inter_channels": inter_channels,
            "resblock": resblock,
            "resblock_kernel_sizes": resblock_kernel_sizes,
            "resblock_dilation_sizes": resblock_dilation_sizes,
            "upsample_rates": upsample_rates,
            "upsample_initial_channel": upsample_initial_channel,
            "upsample_kernel_sizes": upsample_kernel_sizes,
            "gin_channels": gin_channels,
        }
        self.dec = Generator(h=hps)
        self.enc_q = Encoder(spec_channels, inter_channels, hidden_channels, 5, 1, 16, gin_channels=gin_channels)
        self.flow = ResidualCouplingBlock(inter_channels, hidden_channels, 5, 1, 4, gin_channels=gin_channels)
        self.f0_decoder = F0Decoder(
            1,
            hidden_channels,
            filter_channels,
            n_heads,
            n_layers,
            kernel_size,
            p_dropout,
            spk_channels=gin_channels
        )
        self.emb_uv = nn.Embedding(2, hidden_channels)
        self.predict_f0 = False
        self.speaker_map = []
        self.export_mix = False

    def export_chara_mix(self, n_speakers_mix):
        spkmap = []
        for i in range(n_speakers_mix):
            spkmap.append(self.emb_g(torch.LongTensor([[i]])).transpose(1, 2).detach().numpy())
        self.speaker_map = torch.tensor(spkmap)
        self.export_mix = True

    def forward(self, c, f0, mel2ph, uv, noise=None, g=None, cluster_infer_ratio=0.1):

        decoder_inp = F.pad(c, [0, 0, 1, 0])
        mel2ph_ = mel2ph.unsqueeze(2).repeat([1, 1, c.shape[-1]])
        c = torch.gather(decoder_inp, 1, mel2ph_).transpose(1, 2)  # [B, T, H]

        c_lengths = (torch.ones(c.size(0)) * c.size(-1)).to(c.device)

        if self.export_mix:
            spk_mix = spk_mix.unsqueeze(-1).unsqueeze(-1).unsqueeze(-1)
            g = torch.sum(spk_mix * self.speaker_map, dim=0).transpose(1, 2)
        else:
            g = g.unsqueeze(0)
            g = self.emb_g(g).transpose(1, 2)


        x_mask = torch.unsqueeze(commons.sequence_mask(c_lengths, c.size(2)), 1).to(c.dtype)
        x = self.pre(c) * x_mask + self.emb_uv(uv.long()).transpose(1, 2)

        if self.predict_f0:
            lf0 = 2595. * torch.log10(1. + f0.unsqueeze(1) / 700.) / 500
            norm_lf0 = utils.normalize_f0(lf0, x_mask, uv, random_scale=False)
            pred_lf0 = self.f0_decoder(x, norm_lf0, x_mask, spk_emb=g)
            f0 = (700 * (torch.pow(10, pred_lf0 * 500 / 2595) - 1)).squeeze(1)

        z_p, m_p, logs_p, c_mask = self.enc_p(x, x_mask, f0=f0_to_coarse(f0), z=noise)
        z = self.flow(z_p, c_mask, g=g, reverse=True)
        o = self.dec(z * c_mask, g=g, f0=f0)
        return o