import numpy as np
import torch
from torch.utils.serialization import load_lua
import os
import scipy.io as sio
import cv2
import math
from math import cos, sin

def softmax_temperature(tensor, temperature):
    result = torch.exp(tensor / temperature)
    result = torch.div(result, torch.sum(result, 1).unsqueeze(1).expand_as(result))
    return result

def get_pose_params_from_mat(mat_path):
    # This functions gets the pose parameters from the .mat
    # Annotations that come with the Pose_300W_LP dataset.
    mat = sio.loadmat(mat_path)
    # [pitch yaw roll tdx tdy tdz scale_factor]
    pre_pose_params = mat['Pose_Para'][0]
    # Get [pitch, yaw, roll, tdx, tdy]
    pose_params = pre_pose_params[:5]
    return pose_params

def get_ypr_from_mat(mat_path):
    # Get yaw, pitch, roll from .mat annotation.
    # They are in radians
    mat = sio.loadmat(mat_path)
    # [pitch yaw roll tdx tdy tdz scale_factor]
    pre_pose_params = mat['Pose_Para'][0]
    # Get [pitch, yaw, roll]
    pose_params = pre_pose_params[:3]
    return pose_params

def get_pt2d_from_mat(mat_path):
    # Get 2D landmarks
    mat = sio.loadmat(mat_path)
    pt2d = mat['pt2d']
    return pt2d

def mse_loss(input, target):
    return torch.sum(torch.abs(input.data - target.data) ** 2)

def plot_pose_cube(img, yaw, pitch, roll, tdx=None, tdy=None, size=150.):
    # Input is a cv2 image
    # pose_params: (pitch, yaw, roll, tdx, tdy)
    # Where (tdx, tdy) is the translation of the face.
    # For pose we have [pitch yaw roll tdx tdy tdz scale_factor]

    p = pitch * np.pi / 180
    y = -(yaw * np.pi / 180)
    r = roll * np.pi / 180
    if tdx != None and tdy != None:
        face_x = tdx - 0.50 * size
        face_y = tdy - 0.50 * size
    else:
        height, width = img.shape[:2]
        face_x = width / 2 - 0.5 * size
        face_y = height / 2 - 0.5 * size

    x1 = size * (cos(y) * cos(r)) + face_x
    y1 = size * (cos(p) * sin(r) + cos(r) * sin(p) * sin(y)) + face_y
    x2 = size * (-cos(y) * sin(r)) + face_x
    y2 = size * (cos(p) * cos(r) - sin(p) * sin(y) * sin(r)) + face_y
    x3 = size * (sin(y)) + face_x
    y3 = size * (-cos(y) * sin(p)) + face_y

    # Draw base in red
    cv2.line(img, (int(face_x), int(face_y)), (int(x1),int(y1)),(0,0,255),3)
    cv2.line(img, (int(face_x), int(face_y)), (int(x2),int(y2)),(0,0,255),3)
    cv2.line(img, (int(x2), int(y2)), (int(x2+x1-face_x),int(y2+y1-face_y)),(0,0,255),3)
    cv2.line(img, (int(x1), int(y1)), (int(x1+x2-face_x),int(y1+y2-face_y)),(0,0,255),3)
    # Draw pillars in blue
    cv2.line(img, (int(face_x), int(face_y)), (int(x3),int(y3)),(255,0,0),2)
    cv2.line(img, (int(x1), int(y1)), (int(x1+x3-face_x),int(y1+y3-face_y)),(255,0,0),2)
    cv2.line(img, (int(x2), int(y2)), (int(x2+x3-face_x),int(y2+y3-face_y)),(255,0,0),2)
    cv2.line(img, (int(x2+x1-face_x),int(y2+y1-face_y)), (int(x3+x1+x2-2*face_x),int(y3+y2+y1-2*face_y)),(255,0,0),2)
    # Draw top in green
    cv2.line(img, (int(x3+x1-face_x),int(y3+y1-face_y)), (int(x3+x1+x2-2*face_x),int(y3+y2+y1-2*face_y)),(0,255,0),2)
    cv2.line(img, (int(x2+x3-face_x),int(y2+y3-face_y)), (int(x3+x1+x2-2*face_x),int(y3+y2+y1-2*face_y)),(0,255,0),2)
    cv2.line(img, (int(x3), int(y3)), (int(x3+x1-face_x),int(y3+y1-face_y)),(0,255,0),2)
    cv2.line(img, (int(x3), int(y3)), (int(x3+x2-face_x),int(y3+y2-face_y)),(0,255,0),2)

    return img

def draw_axis(img, yaw, pitch, roll, tdx=None, tdy=None, size = 100):

    pitch = pitch * np.pi / 180
    yaw = -(yaw * np.pi / 180)
    roll = roll * np.pi / 180

    if tdx != None and tdy != None:
        tdx = tdx
        tdy = tdy
    else:
        height, width = img.shape[:2]
        tdx = width / 2
        tdy = height / 2

    # X-Axis pointing to right. drawn in red
    x1 = size * (cos(yaw) * cos(roll)) + tdx
    y1 = size * (cos(pitch) * sin(roll) + cos(roll) * sin(pitch) * sin(yaw)) + tdy

    # Y-Axis | drawn in green
    #        v
    x2 = size * (-cos(yaw) * sin(roll)) + tdx
    y2 = size * (cos(pitch) * cos(roll) - sin(pitch) * sin(yaw) * sin(roll)) + tdy

    # Z-Axis (out of the screen) drawn in blue
    x3 = size * (sin(yaw)) + tdx
    y3 = size * (-cos(yaw) * sin(pitch)) + tdy

    cv2.line(img, (int(tdx), int(tdy)), (int(x1),int(y1)),(0,0,255),3)
    cv2.line(img, (int(tdx), int(tdy)), (int(x2),int(y2)),(0,255,0),3)
    cv2.line(img, (int(tdx), int(tdy)), (int(x3),int(y3)),(255,0,0),2)

    return img