import torch

import torch.nn as nn

import torch.nn.functional as F

from inpainting.model.basemodel import BaseModel

from inpainting.model.basenet import BaseNet

from inpainting.model.loss import WGANLoss, IDMRFLoss

from inpainting.model.layer import init_weights, PureUpsampling, ConfidenceDrivenMaskLayer, SpectralNorm

import numpy as np

# generative multi-column convolutional neural net

class GMCNN(BaseNet):

    def __init__(self, in_channels, out_channels, cnum=32, act=F.elu, norm=F.instance_norm, using_norm=False):

        super(GMCNN, self).__init__()

        self.act = act

        self.using_norm = using_norm

        if using_norm is True:

            self.norm = norm

        else:

            self.norm = None

        ch = cnum

        # network structure

        self.EB1 = []

        self.EB2 = []

        self.EB3 = []

        self.decoding_layers = []

        self.EB1_pad_rec = []

        self.EB2_pad_rec = []

        self.EB3_pad_rec = []

        self.EB1.append(nn.Conv2d(in_channels, ch, kernel_size=7, stride=1))

        self.EB1.append(nn.Conv2d(ch, ch * 2, kernel_size=7, stride=2))

        self.EB1.append(nn.Conv2d(ch * 2, ch * 2, kernel_size=7, stride=1))

        self.EB1.append(nn.Conv2d(ch * 2, ch * 4, kernel_size=7, stride=2))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1, dilation=2))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1, dilation=4))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1, dilation=8))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1, dilation=16))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1))

        self.EB1.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=7, stride=1))

        self.EB1.append(PureUpsampling(scale=4))

        self.EB1_pad_rec = [3, 3, 3, 3, 3, 3, 6, 12, 24, 48, 3, 3, 0]

        self.EB2.append(nn.Conv2d(in_channels, ch, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch, ch * 2, kernel_size=5, stride=2))

        self.EB2.append(nn.Conv2d(ch * 2, ch * 2, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch * 2, ch * 4, kernel_size=5, stride=2))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1, dilation=2))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1, dilation=4))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1, dilation=8))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1, dilation=16))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, stride=1))

        self.EB2.append(PureUpsampling(scale=2, mode='nearest'))

        self.EB2.append(nn.Conv2d(ch * 4, ch * 2, kernel_size=5, stride=1))

        self.EB2.append(nn.Conv2d(ch * 2, ch * 2, kernel_size=5, stride=1))

        self.EB2.append(PureUpsampling(scale=2))

        self.EB2_pad_rec = [2, 2, 2, 2, 2, 2, 4, 8, 16, 32, 2, 2, 0, 2, 2, 0]

        self.EB3.append(nn.Conv2d(in_channels, ch, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch, ch * 2, kernel_size=3, stride=2))

        self.EB3.append(nn.Conv2d(ch * 2, ch * 2, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch * 2, ch * 4, kernel_size=3, stride=2))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1, dilation=2))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1, dilation=4))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1, dilation=8))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1, dilation=16))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=3, stride=1))

        self.EB3.append(PureUpsampling(scale=2, mode='nearest'))

        self.EB3.append(nn.Conv2d(ch * 4, ch * 2, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch * 2, ch * 2, kernel_size=3, stride=1))

        self.EB3.append(PureUpsampling(scale=2, mode='nearest'))

        self.EB3.append(nn.Conv2d(ch * 2, ch, kernel_size=3, stride=1))

        self.EB3.append(nn.Conv2d(ch, ch, kernel_size=3, stride=1))

        self.EB3_pad_rec = [1, 1, 1, 1, 1, 1, 2, 4, 8, 16, 1, 1, 0, 1, 1, 0, 1, 1]

        self.decoding_layers.append(nn.Conv2d(ch * 7, ch // 2, kernel_size=3, stride=1))

        self.decoding_layers.append(nn.Conv2d(ch // 2, out_channels, kernel_size=3, stride=1))

        self.decoding_pad_rec = [1, 1]

        self.EB1 = nn.ModuleList(self.EB1)

        self.EB2 = nn.ModuleList(self.EB2)

        self.EB3 = nn.ModuleList(self.EB3)

        self.decoding_layers = nn.ModuleList(self.decoding_layers)

        # padding operations

        padlen = 49

        self.pads = [0] * padlen

        for i in range(padlen):

            self.pads[i] = nn.ReflectionPad2d(i)

        self.pads = nn.ModuleList(self.pads)

    def forward(self, x):

        x1, x2, x3 = x, x, x

        for i, layer in enumerate(self.EB1):

            pad_idx = self.EB1_pad_rec[i]

            x1 = layer(self.pads[pad_idx](x1))

            if self.using_norm:

                x1 = self.norm(x1)

            if pad_idx != 0:

                x1 = self.act(x1)

        for i, layer in enumerate(self.EB2):

            pad_idx = self.EB2_pad_rec[i]

            x2 = layer(self.pads[pad_idx](x2))

            if self.using_norm:

                x2 = self.norm(x2)

            if pad_idx != 0:

                x2 = self.act(x2)

        for i, layer in enumerate(self.EB3):

            pad_idx = self.EB3_pad_rec[i]

            x3 = layer(self.pads[pad_idx](x3))

            if self.using_norm:

                x3 = self.norm(x3)

            if pad_idx != 0:

                x3 = self.act(x3)

        x_d = torch.cat((x1, x2, x3), 1)

        x_d = self.act(self.decoding_layers[0](self.pads[self.decoding_pad_rec[0]](x_d)))

        x_d = self.decoding_layers[1](self.pads[self.decoding_pad_rec[1]](x_d))

        x_out = torch.clamp(x_d, -1, 1)

        return x_out

# return one dimensional output indicating the probability of realness or fakeness

class Discriminator(BaseNet):

    def __init__(self, in_channels, cnum=32, fc_channels=8 * 8 * 32 * 4, act=F.elu, norm=None, spectral_norm=True):

        super(Discriminator, self).__init__()

        self.act = act

        self.norm = norm

        self.embedding = None

        self.logit = None

        ch = cnum

        self.layers = []

        if spectral_norm:

            self.layers.append(SpectralNorm(nn.Conv2d(in_channels, ch, kernel_size=5, padding=2, stride=2)))

            self.layers.append(SpectralNorm(nn.Conv2d(ch, ch * 2, kernel_size=5, padding=2, stride=2)))

            self.layers.append(SpectralNorm(nn.Conv2d(ch * 2, ch * 4, kernel_size=5, padding=2, stride=2)))

            self.layers.append(SpectralNorm(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, padding=2, stride=2)))

            self.layers.append(SpectralNorm(nn.Linear(fc_channels, 1)))

        else:

            self.layers.append(nn.Conv2d(in_channels, ch, kernel_size=5, padding=2, stride=2))

            self.layers.append(nn.Conv2d(ch, ch * 2, kernel_size=5, padding=2, stride=2))

            self.layers.append(nn.Conv2d(ch * 2, ch * 4, kernel_size=5, padding=2, stride=2))

            self.layers.append(nn.Conv2d(ch * 4, ch * 4, kernel_size=5, padding=2, stride=2))

            self.layers.append(nn.Linear(fc_channels, 1))

        self.layers = nn.ModuleList(self.layers)

    def forward(self, x):

        for layer in self.layers[:-1]:

            x = layer(x)

            if self.norm is not None:

                x = self.norm(x)

            x = self.act(x)

        self.embedding = x.view(x.size(0), -1)

        self.logit = self.layers[-1](self.embedding)

        return self.logit

class GlobalLocalDiscriminator(BaseNet):

    def __init__(self, in_channels, cnum=32, g_fc_channels=16 * 16 * 32 * 4, l_fc_channels=8 * 8 * 32 * 4, act=F.elu,

                 norm=None,

                 spectral_norm=True):

        super(GlobalLocalDiscriminator, self).__init__()

        self.act = act

        self.norm = norm

        self.global_discriminator = Discriminator(in_channels=in_channels, fc_channels=g_fc_channels, cnum=cnum,

                                                  act=act, norm=norm, spectral_norm=spectral_norm)

        self.local_discriminator = Discriminator(in_channels=in_channels, fc_channels=l_fc_channels, cnum=cnum,

                                                 act=act, norm=norm, spectral_norm=spectral_norm)

    def forward(self, x_g, x_l):

        x_global = self.global_discriminator(x_g)

        x_local = self.local_discriminator(x_l)

        return x_global, x_local

from inpainting.util.utils import generate_mask

class InpaintingModel_GMCNN(BaseModel):

    def __init__(self, in_channels, act=F.elu, norm=None, opt=None):

        super(InpaintingModel_GMCNN, self).__init__()

        self.opt = opt

        self.init(opt)

        self.confidence_mask_layer = ConfidenceDrivenMaskLayer()

        self.netGM = GMCNN(in_channels, out_channels=3, cnum=opt.g_cnum, act=act, norm=norm).cuda()

        init_weights(self.netGM)

        self.model_names = ['GM']

        if self.opt.phase == 'test':

            return

        self.netD = None

        self.optimizer_G = torch.optim.Adam(self.netGM.parameters(), lr=opt.lr, betas=(0.5, 0.9))

        self.optimizer_D = None

        self.wganloss = None

        self.recloss = nn.L1Loss()

        self.aeloss = nn.L1Loss()

        self.mrfloss = None

        self.lambda_adv = opt.lambda_adv

        self.lambda_rec = opt.lambda_rec

        self.lambda_ae = opt.lambda_ae

        self.lambda_gp = opt.lambda_gp

        self.lambda_mrf = opt.lambda_mrf

        self.G_loss = None

        self.G_loss_reconstruction = None

        self.G_loss_mrf = None

        self.G_loss_adv, self.G_loss_adv_local = None, None

        self.G_loss_ae = None

        self.D_loss, self.D_loss_local = None, None

        self.GAN_loss = None

        self.gt, self.gt_local = None, None

        self.mask, self.mask_01 = None, None

        self.rect = None

        self.im_in, self.gin = None, None

        self.completed, self.completed_local = None, None

        self.completed_logit, self.completed_local_logit = None, None

        self.gt_logit, self.gt_local_logit = None, None

        self.pred = None

        if self.opt.pretrain_network is False:

            self.netD = GlobalLocalDiscriminator(3, cnum=opt.d_cnum, act=act,

                                                 spectral_norm=self.opt.spectral_norm,

                                                 g_fc_channels=opt.img_shapes[0] // 16 * opt.img_shapes[

                                                     1] // 16 * opt.d_cnum * 4,

                                                 l_fc_channels=opt.img_shapes[0] // 16 * opt.img_shapes[

                                                     1] // 16 * opt.d_cnum * 4).cuda()

            init_weights(self.netD)

            self.optimizer_D = torch.optim.Adam(filter(lambda x: x.requires_grad, self.netD.parameters()), lr=opt.lr,

                                                betas=(0.5, 0.9))

            self.wganloss = WGANLoss()

            self.mrfloss = IDMRFLoss()

    def initVariables(self):

        self.gt = self.img

        mask = self.mask

        # mask, rect = generate_mask(self.opt.mask_type, self.opt.img_shapes, self.opt.mask_shapes)

        # self.mask_01 = torch.from_numpy(mask).cuda().repeat([self.opt.batch_size, 1, 1, 1])

        self.mask = self.confidence_mask_layer(mask)

        self.gt_local = self.gt

        self.im_in = self.gt * (1 - self.mask_01)

        self.gin = torch.cat((self.im_in, self.mask_01), 1)

    def forward_G(self):

        self.G_loss_reconstruction = self.recloss(self.completed * self.mask, self.gt.detach() * self.mask)

        self.G_loss_reconstruction = self.G_loss_reconstruction / torch.mean(self.mask_01)

        self.G_loss_ae = self.aeloss(self.pred * (1 - self.mask_01), self.gt.detach() * (1 - self.mask_01))

        self.G_loss_ae = self.G_loss_ae / torch.mean(1 - self.mask_01)

        self.G_loss = self.lambda_rec * self.G_loss_reconstruction + self.lambda_ae * self.G_loss_ae

        self.completed_logit, self.completed_local_logit = self.netD(self.completed, self.completed_local)

        self.G_loss_mrf = self.mrfloss((self.completed_local + 1) / 2.0, (self.gt_local.detach() + 1) / 2.0)

        self.G_loss = self.G_loss + self.lambda_mrf * self.G_loss_mrf

        self.G_loss_adv = -self.completed_logit.mean()

        self.G_loss_adv_local = -self.completed_local_logit.mean()

        self.G_loss = self.G_loss + self.lambda_adv * (self.G_loss_adv + self.G_loss_adv_local)

    def forward_D(self):

        self.completed_logit, self.completed_local_logit = self.netD(self.completed.detach(),

                                                                     self.completed_local.detach())

        self.gt_logit, self.gt_local_logit = self.netD(self.gt, self.gt_local)

        # hinge loss

        self.D_loss_local = nn.ReLU()(1.0 - self.gt_local_logit).mean() + nn.ReLU()(

            1.0 + self.completed_local_logit).mean()

        self.D_loss = nn.ReLU()(1.0 - self.gt_logit).mean() + nn.ReLU()(1.0 + self.completed_logit).mean()

        self.D_loss = self.D_loss + self.D_loss_local

    def backward_G(self):

        self.G_loss.backward()

    def backward_D(self):

        self.D_loss.backward(retain_graph=True)

    def optimize_parameters(self):

        self.initVariables()

        self.pred = self.netGM(self.gin)

        self.completed = self.pred * self.mask_01 + self.gt * (1 - self.mask_01)

        self.completed_local = self.completed

        for i in range(self.opt.D_max_iters):

            self.optimizer_D.zero_grad()

            self.optimizer_G.zero_grad()

            self.forward_D()

            self.backward_D()

            self.optimizer_D.step()

        self.optimizer_G.zero_grad()

        self.forward_G()

        self.backward_G()

        self.optimizer_G.step()

    def get_current_losses(self):

        l = {'G_loss': self.G_loss.item(), 'G_loss_rec': self.G_loss_reconstruction.item(),

             'G_loss_ae': self.G_loss_ae.item()}

        if self.opt.pretrain_network is False:

            l.update({'G_loss_adv': self.G_loss_adv.item(),

                      'G_loss_adv_local': self.G_loss_adv_local.item(),

                      'D_loss': self.D_loss.item(),

                      'G_loss_mrf': self.G_loss_mrf.item()})

        return l

    def get_current_visuals(self):

        return {'input': self.im_in.cpu().detach().numpy(), 'gt': self.gt.cpu().detach().numpy(),

                'completed': self.completed.cpu().detach().numpy()}

    def get_current_visuals_tensor(self):

        return {'input': self.im_in.cpu().detach(), 'gt': self.gt.cpu().detach(),

                'completed': self.completed.cpu().detach()}

    def evaluate(self, im_in, mask):

        im_in = torch.from_numpy(im_in).type(torch.FloatTensor).cuda() / 127.5 - 1

        mask = torch.from_numpy(mask).type(torch.FloatTensor).cuda()

        im_in = im_in * (1 - mask)

        xin = torch.cat((im_in, mask), 1)

        ret = self.netGM(xin) * mask + im_in * (1 - mask)

        ret = (ret.cpu().detach().numpy() + 1) * 127.5

        return ret.astype(np.uint8)