#coding:utf-8

import os
import math
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.nn.utils import weight_norm, spectral_norm
# from Utils.ASR.models import ASRCNN
from Utils.JDC.model import JDCNet
from Modules.hifigan import _tile, AdainResBlk1d
import yaml


class LearnedDownSample(nn.Module):
    def __init__(self, layer_type, dim_in):
        super().__init__()
        self.layer_type = layer_type

        if self.layer_type == 'none':
            raise ValueError
            # self.conv = nn.Identity()
        elif self.layer_type == 'timepreserve':
            raise ValueError
            # self.conv = spectral_norm(nn.Conv2d(dim_in, dim_in, kernel_size=(3, 1), stride=(2, 1), groups=dim_in, padding=(1, 0)))
        elif self.layer_type == 'half':
            self.conv = spectral_norm(nn.Conv2d(dim_in, dim_in, kernel_size=(3, 3), stride=(2, 2), groups=dim_in, padding=1))
        else:
            raise RuntimeError('Got unexpected donwsampletype %s, expected is [none, timepreserve, half]' % self.layer_type)

    def forward(self, x):
        return self.conv(x)


class DownSample(nn.Module):
    def __init__(self, layer_type):
        super().__init__()
        self.layer_type = layer_type

    def forward(self, x):
        if self.layer_type == 'none':
            return x
        elif self.layer_type == 'timepreserve':
            return F.avg_pool2d(x, (2, 1))
        elif self.layer_type == 'half':
            if x.shape[-1] % 2 != 0:
                x = torch.cat([x, x[..., -1].unsqueeze(-1)], dim=-1)
            return F.avg_pool2d(x, 2)
        else:
            raise RuntimeError('Got unexpected donwsampletype %s, expected is [none, timepreserve, half]' % self.layer_type)





class ResBlk(nn.Module):
    def __init__(self, dim_in, dim_out, actv=nn.LeakyReLU(0.2),
                 normalize=False, downsample='none'):
        super().__init__()
        self.actv = actv
        self.normalize = normalize
        self.downsample = DownSample(downsample)
        self.downsample_res = LearnedDownSample(downsample, dim_in)
        self.learned_sc = dim_in != dim_out
        self._build_weights(dim_in, dim_out)

    def _build_weights(self, dim_in, dim_out):
        self.conv1 = spectral_norm(nn.Conv2d(dim_in, dim_in, 3, 1, 1))
        self.conv2 = spectral_norm(nn.Conv2d(dim_in, dim_out, 3, 1, 1))
        if self.normalize:
            self.norm1 = nn.InstanceNorm2d(dim_in, affine=True)
            self.norm2 = nn.InstanceNorm2d(dim_in, affine=True)
        if self.learned_sc:
            self.conv1x1 = spectral_norm(nn.Conv2d(dim_in, dim_out, 1, 1, 0, bias=False))

    def _shortcut(self, x):
        if self.learned_sc:
            x = self.conv1x1(x)
        if self.downsample:
            x = self.downsample(x)
        return x

    def _residual(self, x):
        if self.normalize:
            x = self.norm1(x)
        x = self.actv(x)
        x = self.conv1(x)
        x = self.downsample_res(x)
        if self.normalize:
            x = self.norm2(x)
        x = self.actv(x)
        x = self.conv2(x)
        return x

    def forward(self, x):
        x = self._shortcut(x) + self._residual(x)
        return x / math.sqrt(2)  # unit variance


class StyleEncoder(nn.Module):

    #  for both acoustic & prosodic ref_s/p

    def __init__(self, dim_in=48, style_dim=48, max_conv_dim=384):
        super().__init__()
        blocks = []
        blocks += [spectral_norm(nn.Conv2d(1, dim_in, 3, 1, 1))]

        repeat_num = 4
        for _ in range(repeat_num):
            dim_out = min(dim_in*2, max_conv_dim)
            blocks += [ResBlk(dim_in, dim_out, downsample='half')]
            dim_in = dim_out

        blocks += [nn.LeakyReLU(0.2)]
        blocks += [spectral_norm(nn.Conv2d(dim_out, dim_out, 5, 1, 0))]
        
        # blocks += [nn.AdaptiveAvgPool2d(1)]   # THIS AVERAGES THE TIME-FRAMES OF SPEAKER STYLE
        
        blocks += [nn.LeakyReLU(0.2)]
        self.shared = nn.Sequential(*blocks)

        self.unshared = nn.Linear(dim_out, style_dim)

    def forward(self, x):
        h = self.shared(x)  # [bs, 512, 1, 11]
        
        h = h.mean(3, keepdims=True)  # UN COMMENT FOR TIME INVARIANT GLOBAL SPEAKER STYLE
        # h = .7 * h + .25 * h.mean(3, keepdims=True)
        h = h.transpose(1, 3)
        s = self.unshared(h)
        
        
        return s


class LinearNorm(torch.nn.Module):
    def __init__(self, in_dim, out_dim, bias=True, w_init_gain='linear'):
        super(LinearNorm, self).__init__()
        self.linear_layer = torch.nn.Linear(in_dim, out_dim, bias=bias)

        torch.nn.init.xavier_uniform_(
            self.linear_layer.weight,
            gain=torch.nn.init.calculate_gain(w_init_gain))

    def forward(self, x):
        return self.linear_layer(x)


class ResBlk1d(nn.Module):
    def __init__(self, dim_in, dim_out, actv=nn.LeakyReLU(0.2),
                 normalize=False, downsample='none', dropout_p=0.2):
        super().__init__()
        self.actv = actv
        self.normalize = normalize
        self.downsample_type = downsample
        self.learned_sc = dim_in != dim_out
        self._build_weights(dim_in, dim_out)
        self.dropout_p = dropout_p
        
        if self.downsample_type == 'none':
            self.pool = nn.Identity()
        else:
            self.pool = weight_norm(nn.Conv1d(dim_in, dim_in, kernel_size=3, stride=2, groups=dim_in, padding=1))

    def _build_weights(self, dim_in, dim_out):
        self.conv1 = weight_norm(nn.Conv1d(dim_in, dim_in, 3, 1, 1))
        self.conv2 = weight_norm(nn.Conv1d(dim_in, dim_out, 3, 1, 1))
        if self.normalize:
            self.norm1 = nn.InstanceNorm1d(dim_in, affine=True)
            self.norm2 = nn.InstanceNorm1d(dim_in, affine=True)
        if self.learned_sc:
            self.conv1x1 = weight_norm(nn.Conv1d(dim_in, dim_out, 1, 1, 0, bias=False))

    def downsample(self, x):
        if self.downsample_type == 'none':
            return x
        else:
            if x.shape[-1] % 2 != 0:
                x = torch.cat([x, x[..., -1].unsqueeze(-1)], dim=-1)
            return F.avg_pool1d(x, 2)

    def _shortcut(self, x):
        if self.learned_sc:
            x = self.conv1x1(x)
        x = self.downsample(x)
        return x

    def _residual(self, x):
        if self.normalize:
            x = self.norm1(x)
        x = self.actv(x)
        x = F.dropout(x, p=self.dropout_p, training=self.training)
        
        x = self.conv1(x)
        x = self.pool(x)
        if self.normalize:
            x = self.norm2(x)
            
        x = self.actv(x)
        x = F.dropout(x, p=self.dropout_p, training=self.training)
        
        x = self.conv2(x)
        return x

    def forward(self, x):
        x = self._shortcut(x) + self._residual(x)
        return x / math.sqrt(2)  # unit variance


class LayerNorm(nn.Module):
    def __init__(self, channels, eps=1e-5):
        super().__init__()
        self.channels = channels
        self.eps = eps

        self.gamma = nn.Parameter(torch.ones(channels))
        self.beta = nn.Parameter(torch.zeros(channels))

    def forward(self, x):
        x = x.transpose(1, -1)
        x = F.layer_norm(x, (self.channels,), self.gamma, self.beta, self.eps)
        return x.transpose(1, -1)

class TextEncoder(nn.Module):
    def __init__(self, channels, kernel_size, depth, n_symbols, actv=nn.LeakyReLU(0.2)):
        super().__init__()
        self.embedding = nn.Embedding(n_symbols, channels)

        padding = (kernel_size - 1) // 2
        self.cnn = nn.ModuleList()
        for _ in range(depth):
            self.cnn.append(nn.Sequential(
                weight_norm(nn.Conv1d(channels, channels, kernel_size=kernel_size, padding=padding)),
                LayerNorm(channels),
                actv,
                nn.Dropout(0.2),
            ))
        # self.cnn = nn.Sequential(*self.cnn)

        self.lstm = nn.LSTM(channels, channels//2, 1, batch_first=True, bidirectional=True)

    def forward(self, x, input_lengths):
        x = self.embedding(x)  # [B, T, emb]
        x = x.transpose(1, 2)  # [B, emb, T]
        for c in self.cnn:
            x = c(x)    
        x = x.transpose(1, 2)  # [B, T, chn]
        input_lengths = input_lengths.cpu().numpy()
        x = nn.utils.rnn.pack_padded_sequence(
            x, input_lengths,
            batch_first=True,
            enforce_sorted=False)
        self.lstm.flatten_parameters()
        x, _ = self.lstm(x)
        x, _ = nn.utils.rnn.pad_packed_sequence(
            x, batch_first=True)
        x = x.transpose(-1, -2)
        return x
    
class AdaLayerNorm(nn.Module):
    
    # only instantianted in DurationPredictor()
    
    def __init__(self, style_dim, channels=None, eps=1e-5):
        super().__init__()
        self.eps = eps
        self.fc = nn.Linear(style_dim, 1024)

    def forward(self, x, s):
        h = self.fc(s.transpose(1, 2))  # has to be transposed due to interpolate needing the last dim to be frames
        gamma = h[:, :, :512]
        beta = h[:, :, 512:1024]
        
        x = F.layer_norm(x.transpose(1, 2), (512, ), eps=self.eps)
        x = (1 + gamma) * x + beta
        return x  # [1, 75, 512]

class ProsodyPredictor(nn.Module):

    def __init__(self, style_dim, d_hid, nlayers, max_dur=50, dropout=0.1):
        super().__init__() 
        
        self.text_encoder = DurationEncoder(sty_dim=style_dim, 
                                            d_model=d_hid,
                                            nlayers=nlayers, 
                                            dropout=dropout)

        self.lstm = nn.LSTM(d_hid + style_dim, d_hid // 2, 1, batch_first=True, bidirectional=True)
        self.duration_proj = LinearNorm(d_hid, max_dur)
        
        self.shared = nn.LSTM(d_hid + style_dim, d_hid // 2, 1, batch_first=True, bidirectional=True)
        self.F0 = nn.ModuleList()
        self.F0.append(AdainResBlk1d(d_hid, d_hid, style_dim, dropout_p=dropout))
        self.F0.append(AdainResBlk1d(d_hid, d_hid // 2, style_dim, upsample=True, dropout_p=dropout))
        self.F0.append(AdainResBlk1d(d_hid // 2, d_hid // 2, style_dim, dropout_p=dropout))

        self.N = nn.ModuleList()
        self.N.append(AdainResBlk1d(d_hid, d_hid, style_dim, dropout_p=dropout))
        self.N.append(AdainResBlk1d(d_hid, d_hid // 2, style_dim, upsample=True, dropout_p=dropout))
        self.N.append(AdainResBlk1d(d_hid // 2, d_hid // 2, style_dim, dropout_p=dropout))
        
        self.F0_proj = nn.Conv1d(d_hid // 2, 1, 1, 1, 0)
        self.N_proj = nn.Conv1d(d_hid // 2, 1, 1, 1, 0)
    
    def F0Ntrain(self, x, s):
        print(x.shape, s.shape, 'F)N T T T')
        x, _ = self.shared(x.transpose(1, 2))  # [bs, time, ch] LSTM

        x = x.transpose(1, 2)  # [bs, ch, time]
        
        
        F0 = x
        
        for block in self.F0:
            print(f'LOOP {F0.shape=} {s.shape=}\n')
            # )N F0.shape=torch.Size([1, 512, 147]) s.shape=torch.Size([1, 128])
            F0 = block(F0, s)  # This is an AdainResBlk1d expects conv1d dimensions
        F0 = self.F0_proj(F0)
        print('____________________________2nd F0Ntra')
        N = x
        
        for block in self.N:
            N = block(N, s)
        N = self.N_proj(N)
        
        return F0, N

class DurationEncoder(nn.Module):

    def __init__(self, sty_dim, d_model, nlayers, dropout=0.1):
        super().__init__()
        self.lstms = nn.ModuleList()
        for _ in range(nlayers):
            self.lstms.append(nn.LSTM(d_model + sty_dim, 
                                 d_model // 2, 
                                 num_layers=1, 
                                 batch_first=True, 
                                 bidirectional=True, 
                                 dropout=dropout))
            self.lstms.append(AdaLayerNorm(sty_dim, d_model))
        
        
        self.dropout = dropout
        self.d_model = d_model
        self.sty_dim = sty_dim

    def forward(self, x, style, text_lengths):

        # style = style[:, :, 0, :].transpose(2, 1)  # [bs, 128, 11]
        
        style = _tile(style, length=x.shape[2])  # replicate style vector to duration of txt - F.interpolate or cyclic/tile

        x = torch.cat([x, style], axis=1)  # [bs, 640, 75]

        input_lengths = text_lengths.cpu().numpy()
        
        for block in self.lstms:
            if isinstance(block, AdaLayerNorm):
                
                print(f'\n=========ENTER ADALAYNORM L479 models.py {x.shape=}, {style.shape=}')
                x = block(x, style)   # [bs, 75, 512]
                x = torch.cat([x.transpose(1, 2), style], axis=1) # [bs, 512, 75]

            else:
                # print(f'{x.shape=} ENTER LSTM')  # [bs, 640, 75]  LSTM reduce ch 640 -> 512
                x = x.transpose(-1, -2)
                x = nn.utils.rnn.pack_padded_sequence(
                    x, input_lengths, batch_first=True, enforce_sorted=False)
                block.flatten_parameters()
                x, _ = block(x)
                x, _ = nn.utils.rnn.pad_packed_sequence(
                    x, batch_first=True)
                x = F.dropout(x, p=self.dropout, training=self.training)
                x = x.transpose(-1, -2)
        return x.transpose(-1, -2)

    
    
    
def load_F0_models(path):
    # load F0 model

    F0_model = JDCNet(num_class=1, seq_len=192)
    path = path.replace('.t7', '.pth')
    params = torch.load(path, map_location='cpu')['net']
    F0_model.load_state_dict(params)
    _ = F0_model.train()
    
    return F0_model