import requests
import json
import os
import asyncio
import argparse
from datetime import datetime
import writer
from model import PictureType
import sys

def parse_args(argv =None):
    parser = argparse.ArgumentParser()
    parser.add_argument('--sequence_ids', type=str, nargs='+', help='The mapillary sequence id(s) to download')
    parser.add_argument('--access_token', type=str, help='Your mapillary access token')
    parser.add_argument('--image_count', type=int, default=None, help='How many images you want to download')

    global args
    args = parser.parse_args(argv)

def background(f):
    def wrapped(*args, **kwargs):
        return asyncio.get_event_loop().run_in_executor(None, f, *args, **kwargs)
    return wrapped

#@background
def download(url, fn, metadata=None):
    r = requests.get(url, stream=True)
    image = write_exif(r.content, metadata)
    with open(str(fn), "wb") as f:
        f.write(image)

def get_single_image_data(image_id, mly_header):
    req_url = 'https://graph.mapillary.com/{}?fields=thumb_original_url,altitude,camera_type,captured_at,compass_angle,geometry,exif_orientation'.format(image_id)
    r = requests.get(req_url, headers=mly_header)
    data = r.json()
    #print(data)
    return data

def get_image_data_from_sequences(sequences_id, mly_header):
    for i,sequence_id in enumerate(sequences_id):
        url = 'https://graph.mapillary.com/image_ids?sequence_id={}'.format(sequence_id)
        r = requests.get(url, headers=header)
        data = r.json()
        image_ids = data['data']
        total_image = len(image_ids)
        print("{} images in sequence {} of {}  - id : {}".format(total_image, i+1, len(sequences_id), sequence_id))
        print('getting images data')
        for x in range(0, total_image):
            image_id = image_ids[x]['id']
            image_data = get_single_image_data(image_id, mly_header)
            image_data['sequence_id'] = sequence_id
            yield image_data

def write_exif(picture, img_metadata):
    '''
    Write exif metadata
    '''
    #{'thumb_original_url': 'https://scontent-cdg4-2.xx.fbcdn.net/m1/v/t6/An9Zy2SrH9vXJIF01QkBODyUbg7XSKfwL48UwHyvihSwvECGjVbG0vSw9uhxe2-Dq-k2eUcigb83buO6zo-7eVbykfp5aQIe1kgd-MJr66nU_H-o_mwBLZXgVbj5I_5WX-C9c6FxJruHkV962F228O0?ccb=10-5&oh=00_AfDOKD869DxL-4ZNCbVo8Rn29vsc0JyjMAU2ctx4aAFVMQ&oe=65256C25&_nc_sid=201bca',
    #  'captured_at': 1603459736644, 'geometry': {'type': 'Point', 'coordinates': [2.5174596904057, 48.777089857534]}, 'id': '485924785946693'}
    
    picture = writer.writePictureMetadata(picture, img_metadata)
    picture = writer.add_altitude(picture, img_metadata)
    picture = writer.add_direction(picture, img_metadata)

    return picture

if __name__ == '__main__':
    parse_args()

    if args.sequence_ids == None:
        print('please provide the sequence_id')
        exit()

    if args.access_token == None:
        print('please provide the access_token')
        exit()

    sequence_ids= args.sequence_ids
    access_token = args.access_token

    # create the data folder
    if not os.path.exists('data'):
            os.makedirs('data')

    images_data = []
    header = {'Authorization' : 'OAuth {}'.format(access_token)}
    # create a folder for each unique sequence ID to group images by sequence
    for sequence_id in sequence_ids:
        if not os.path.exists('data/{}'.format(sequence_id)):
            os.makedirs('data/{}'.format(sequence_id))

    for i,image_data in enumerate(get_image_data_from_sequences(sequence_ids, header)):
        if args.image_count is not None and i >= args.image_count:
            break
        images_data.append(image_data)

    print('downloading.. this process will take a while. please wait')
    for i,image_data in enumerate(images_data):
        date_time_image_filename = datetime.utcfromtimestamp(int(image_data['captured_at'])/1000).strftime('%Y-%m-%d_%HH%Mmn%S.%f')
        path = 'data/{}/{}.jpg'.format(image_data['sequence_id'], date_time_image_filename)
        print(path)
        img_metadata = writer.PictureMetadata(
                capture_time = datetime.utcfromtimestamp(int(image_data['captured_at'])/1000),
                longitude = image_data['geometry']['coordinates'][0],
                latitude = image_data['geometry']['coordinates'][1],
                picture_type = PictureType("equirectangular") if image_data['camera_type'] == 'spherical' else None,
                direction = image_data['compass_angle'],
                altitude = image_data['altitude'],
        )
        download(image_data['thumb_original_url'],path, img_metadata)