from torch.utils.data import DataLoader
import torch
from model.base.geometry import Geometry
from common.evaluation import Evaluator
from common.logger import AverageMeter
from common.logger import Logger
from data import download
from model import chmnet
from matplotlib import pyplot as plt
from matplotlib.patches import ConnectionPatch
from PIL import Image
import numpy as np
import os
import torchvision
import torchvision.transforms as transforms
import torchvision.transforms.functional as TF
import torchvision.models as models
import torch.nn as nn
import torch.nn.functional as F
import random
import gradio as gr

# Downloading the Model
torchvision.datasets.utils.download_file_from_google_drive('1zsJRlAsoOn5F0GTCprSFYwDDfV85xDy6', '.', 'pas_psi.pt')

# Model Initialization
args = dict({
    'alpha' : [0.05, 0.1], 
    'benchmark':'pfpascal', 
    'bsz':90, 
    'datapath':'../Datasets_CHM', 
    'img_size':240, 
    'ktype':'psi', 
    'load':'pas_psi.pt',
    'thres':'img'
    })

model = chmnet.CHMNet(args['ktype'])
model.load_state_dict(torch.load(args['load'], map_location=torch.device('cpu')))
Evaluator.initialize(args['alpha'])
Geometry.initialize(img_size=args['img_size'])
model.eval();

# Transforms

chm_transform = transforms.Compose(
   [transforms.Resize(args['img_size']),
    transforms.CenterCrop((args['img_size'], args['img_size'])),
    transforms.ToTensor(),
    transforms.Normalize(mean=[0.485, 0.456, 0.406],std=[0.229, 0.224, 0.225])])

chm_transform_plot = transforms.Compose(
   [transforms.Resize(args['img_size']),
    transforms.CenterCrop((args['img_size'], args['img_size']))])

# A Helper Function
to_np = lambda x: x.data.to('cpu').numpy()

# Colors for Plotting
cmap = matplotlib.cm.get_cmap('Spectral')
rgba = cmap(0.5)
colors = []
for k in range(49):
  colors.append(cmap(k/49.0))


# CHM MODEL
def run_chm(source_image, target_image, selected_points, number_src_points , chm_transform, display_transform):
      # Convert to Tensor
  src_img_tnsr = chm_transform(source_image).unsqueeze(0)
  tgt_img_tnsr = chm_transform(target_image).unsqueeze(0)

  # Selected_points = selected_points.T 
  keypoints = torch.tensor(selected_points).unsqueeze(0)
  n_pts = torch.tensor(np.asarray([number_src_points]))

  # RUN CHM ------------------------------------------------------------------------
  with torch.no_grad():
    corr_matrix = model(src_img_tnsr, tgt_img_tnsr)
    prd_kps = Geometry.transfer_kps(corr_matrix, keypoints, n_pts, normalized=False)
  
  # VISUALIZATION
  src_points = keypoints[0].squeeze(0).squeeze(0).numpy()
  tgt_points = prd_kps[0].squeeze(0).squeeze(0).cpu().numpy()

  src_points_converted  = []
  w, h = display_transform(source_image).size

  for x,y in zip(src_points[0], src_points[1]):
    src_points_converted.append([int(x*w/args['img_size']),int((y)*h/args['img_size'])])

  src_points_converted = np.asarray(src_points_converted[:number_src_points])
  tgt_points_converted  = []

  w, h = display_transform(target_image).size
  for x, y in zip(tgt_points[0], tgt_points[1]):
    tgt_points_converted.append([int(((x+1)/2.0)*w),int(((y+1)/2.0)*h)])

  tgt_points_converted = np.asarray(tgt_points_converted[:number_src_points])
  
  tgt_grid  = []
  
  for x, y in zip(tgt_points[0], tgt_points[1]):
    tgt_grid.append([int(((x+1)/2.0)*7),int(((y+1)/2.0)*7)])
  
  # PLOT
  fig, ax = plt.subplots(nrows=1, ncols=2, figsize=(12, 8))

  ax[0].imshow(display_transform(source_image))
  ax[0].scatter(src_points_converted[:, 0], src_points_converted[:, 1], c=colors[:number_src_points])
  ax[0].set_title('Source')
  ax[0].set_xticks([])
  ax[0].set_yticks([])

  ax[1].imshow(display_transform(target_image))
  ax[1].scatter(tgt_points_converted[:, 0], tgt_points_converted[:, 1], c=colors[:number_src_points])
  ax[1].set_title('Target')
  ax[1].set_xticks([])
  ax[1].set_yticks([])

  for TL in range(49):
    ax[0].text(x=src_points_converted[TL][0], y=src_points_converted[TL][1], s=str(TL), fontdict=dict(color='red', size=10))

  for TL in range(49):
    ax[1].text(x=tgt_points_converted[TL][0], y=tgt_points_converted[TL][1], s=f'{str(TL)}', fontdict=dict(color='orange', size=8))

  plt.tight_layout()
  fig.suptitle('CHM Correspondences\nUsing $\it{pas\_psi.pt}$ Weights ', fontsize=16)
  return fig


# Wrapper 
def generate_correspondences(sousrce_image, target_image, min_x=1, max_x=100, min_y=1, max_y=100):
  A = np.linspace(min_x, max_x, 7)
  B = np.linspace(min_y, max_y, 7)
  point_list = list(product(A, B))
  new_points = np.asarray(point_list, dtype=np.float64).T
  return run_chm(sousrce_image, target_image, selected_points=new_points, number_src_points=49, chm_transform=chm_transform, display_transform=chm_transform_plot)


# GRADIO APP
iface = gr.Interface(fn=generate_correspondences, 
                     inputs=[gr.inputs.Image(shape=(240, 240), type='pil'), 
                             gr.inputs.Image(shape=(240, 240), type='pil'),
                             gr.inputs.Slider(minimum=1, maximum=240, step=1, default=15, label='MinX'),
                             gr.inputs.Slider(minimum=1, maximum=240, step=1, default=215, label='MaxX'),
                             gr.inputs.Slider(minimum=1, maximum=240, step=1, default=15, label='MinY'),
                             gr.inputs.Slider(minimum=1, maximum=240, step=1, default=215, label='MaxY')], outputs="plot")
iface.launch()