import torch
from torch import nn

from so_vits_svc_fork.modules import attentions as attentions
from so_vits_svc_fork.modules import commons as commons
from so_vits_svc_fork.modules import modules as modules


class SpeakerEncoder(torch.nn.Module):
    def __init__(
        self,
        mel_n_channels=80,
        model_num_layers=3,
        model_hidden_size=256,
        model_embedding_size=256,
    ):
        super().__init__()
        self.lstm = nn.LSTM(
            mel_n_channels, model_hidden_size, model_num_layers, batch_first=True
        )
        self.linear = nn.Linear(model_hidden_size, model_embedding_size)
        self.relu = nn.ReLU()

    def forward(self, mels):
        self.lstm.flatten_parameters()
        _, (hidden, _) = self.lstm(mels)
        embeds_raw = self.relu(self.linear(hidden[-1]))
        return embeds_raw / torch.norm(embeds_raw, dim=1, keepdim=True)

    def compute_partial_slices(self, total_frames, partial_frames, partial_hop):
        mel_slices = []
        for i in range(0, total_frames - partial_frames, partial_hop):
            mel_range = torch.arange(i, i + partial_frames)
            mel_slices.append(mel_range)

        return mel_slices

    def embed_utterance(self, mel, partial_frames=128, partial_hop=64):
        mel_len = mel.size(1)
        last_mel = mel[:, -partial_frames:]

        if mel_len > partial_frames:
            mel_slices = self.compute_partial_slices(
                mel_len, partial_frames, partial_hop
            )
            mels = list(mel[:, s] for s in mel_slices)
            mels.append(last_mel)
            mels = torch.stack(tuple(mels), 0).squeeze(1)

            with torch.no_grad():
                partial_embeds = self(mels)
            embed = torch.mean(partial_embeds, axis=0).unsqueeze(0)
            # embed = embed / torch.linalg.norm(embed, 2)
        else:
            with torch.no_grad():
                embed = self(last_mel)

        return embed


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, noice_scale=1):
        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 + torch.randn_like(m) * torch.exp(logs) * noice_scale) * x_mask

        return z, m, logs, x_mask