import os
import torch
import torch.nn.functional as F
import librosa
import numpy as np
import importlib
import tqdm
import copy
import cv2
from scipy.spatial.transform import Rotation


def load_img_to_512_hwc_array(img_name):
    img = cv2.imread(img_name)
    img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
    img = cv2.resize(img, (512, 512))
    return img

def load_img_to_normalized_512_bchw_tensor(img_name):
    img = load_img_to_512_hwc_array(img_name)
    img = ((torch.tensor(img) - 127.5)/127.5).float().unsqueeze(0).permute(0, 3, 1,2) # [b,c,h,w]
    return img

def mirror_index(index, len_seq):
    """
    get mirror index when indexing a sequence and the index is larger than len_pose
    args:
        index: int
        len_pose: int
    return:
        mirror_index: int
    """
    turn = index // len_seq
    res = index % len_seq
    if turn % 2 == 0:
        return res # forward indexing
    else:
        return len_seq - res - 1 # reverse indexing
    
def smooth_camera_sequence(camera, kernel_size=7):
    """
    smooth the camera trajectory (i.e., rotation & translation)...
    args:
        camera: [N, 25] or [N, 16]. np.ndarray
        kernel_size: int
    return: 
        smoothed_camera: [N, 25] or [N, 16]. np.ndarray
    """
    # poses: [N, 25], numpy array
    N = camera.shape[0]
    K = kernel_size // 2
    poses = camera[:, :16].reshape([-1, 4, 4]).copy()
    trans = poses[:, :3, 3].copy() # [N, 3]
    rots = poses[:, :3, :3].copy() # [N, 3, 3]

    for i in range(N):
        start = max(0, i - K)
        end = min(N, i + K + 1)
        poses[i, :3, 3] = trans[start:end].mean(0)
        try:
            poses[i, :3, :3] = Rotation.from_matrix(rots[start:end]).mean().as_matrix()
        except:
            if i == 0:
                poses[i, :3, :3] = rots[i]
            else:
                poses[i, :3, :3] = poses[i-1, :3, :3]
    poses = poses.reshape([-1, 16])
    camera[:, :16] = poses
    return camera

def smooth_features_xd(in_tensor, kernel_size=7):
    """
    smooth the feature maps
    args:
        in_tensor: [T, c,h,w] or [T, c1,c2,h,w]
        kernel_size: int
    return:
        out_tensor: [T, c,h,w] or [T, c1,c2,h,w]
    """
    t = in_tensor.shape[0]
    ndim = in_tensor.ndim
    pad = (kernel_size- 1)//2
    in_tensor = torch.cat([torch.flip(in_tensor[0:pad], dims=[0]), in_tensor, torch.flip(in_tensor[t-pad:t], dims=[0])], dim=0)
    if ndim == 2: # tc
        _,c = in_tensor.shape
        in_tensor = in_tensor.permute(1,0).reshape([-1,1,t+2*pad]) # [c, 1, t]
    elif ndim == 4: # tchw
        _,c,h,w = in_tensor.shape
        in_tensor = in_tensor.permute(1,2,3,0).reshape([-1,1,t+2*pad]) # [c, 1, t]
    elif ndim == 5: # tcchw, like deformation
        _,c1,c2, h,w = in_tensor.shape
        in_tensor = in_tensor.permute(1,2,3,4,0).reshape([-1,1,t+2*pad]) # [c, 1, t]
    else: raise NotImplementedError()
    avg_kernel = 1 / kernel_size * torch.Tensor([1.]*kernel_size).reshape([1,1,kernel_size]).float().to(in_tensor.device) # [1, 1, kw]
    out_tensor = F.conv1d(in_tensor, avg_kernel)
    if ndim == 2: # tc
        return out_tensor.reshape([c,t]).permute(1,0)
    elif ndim == 4: # tchw
        return out_tensor.reshape([c,h,w,t]).permute(3,0,1,2)
    elif ndim == 5: # tcchw, like deformation
        return out_tensor.reshape([c1,c2,h,w,t]).permute(4,0,1,2,3)


def extract_audio_motion_from_ref_video(video_name):
    def save_wav16k(audio_name):
        supported_types = ('.wav', '.mp3', '.mp4', '.avi')
        assert audio_name.endswith(supported_types), f"Now we only support {','.join(supported_types)} as audio source!"
        wav16k_name = audio_name[:-4] + '_16k.wav'
        extract_wav_cmd = f"ffmpeg -i {audio_name} -f wav -ar 16000 -v quiet -y {wav16k_name} -y"
        os.system(extract_wav_cmd)
        print(f"Extracted wav file (16khz) from {audio_name} to {wav16k_name}.")
        return wav16k_name
    
    def get_f0( wav16k_name):
        from data_gen.utils.process_audio.extract_mel_f0 import extract_mel_from_fname, extract_f0_from_wav_and_mel
        wav, mel = extract_mel_from_fname(wav16k_name)
        f0, f0_coarse = extract_f0_from_wav_and_mel(wav, mel)
        f0 = f0.reshape([-1,1])
        f0 = torch.tensor(f0)
        return f0
    
    def get_hubert(wav16k_name):
        from data_gen.utils.process_audio.extract_hubert import get_hubert_from_16k_wav
        hubert = get_hubert_from_16k_wav(wav16k_name).detach().numpy()
        len_mel = hubert.shape[0]
        x_multiply = 8
        if len_mel % x_multiply == 0:
            num_to_pad = 0
        else:
            num_to_pad = x_multiply - len_mel % x_multiply
        hubert = np.pad(hubert, pad_width=((0,num_to_pad), (0,0)))
        hubert = torch.tensor(hubert)
        return hubert

    def get_exp(video_name):
        from data_gen.utils.process_video.fit_3dmm_landmark import fit_3dmm_for_a_video
        drv_motion_coeff_dict = fit_3dmm_for_a_video(video_name, save=False)
        exp = torch.tensor(drv_motion_coeff_dict['exp'])
        return exp
    
    wav16k_name = save_wav16k(video_name)
    f0 = get_f0(wav16k_name)
    hubert = get_hubert(wav16k_name)
    os.system(f"rm {wav16k_name}")
    exp = get_exp(video_name)
    target_length = min(len(exp), len(hubert)//2, len(f0)//2)
    exp = exp[:target_length]
    f0 = f0[:target_length*2]
    hubert = hubert[:target_length*2]
    return exp.unsqueeze(0), hubert.unsqueeze(0), f0.unsqueeze(0)


if __name__ == '__main__':
    extract_audio_motion_from_ref_video('data/raw/videos/crop_0213.mp4')