#!/usr/bin/env python

#
# Copyright (c) 2011 Brian House
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# 
# See <http://www.gnu.org/licenses/gpl.html> for details.
# 

""" http://blog.brianhouse.net/post/7359294387
    http://openpaths.cc/api    
"""    

import os, oauth2, time, urllib, urllib2, json
from PIL import Image

ACCESS = "YOURACCESSKEYHERE"
SECRET = "YOURSECRETKEYHERE"
URL = "https://openpaths.cc/api" 

def get_points():
    """Download JSON data from OpenPaths"""    
    
    def build_request(url, method):
        params = {                                            
            'oauth_version': "1.0",
            'oauth_nonce': oauth2.generate_nonce(),
            'oauth_timestamp': int(time.time()),
        }
        consumer = oauth2.Consumer(key=ACCESS, secret=SECRET)
        params['oauth_consumer_key'] = consumer.key 
        request = oauth2.Request(method=method, url=url, parameters=params)
        signature_method = oauth2.SignatureMethod_HMAC_SHA1()
        request.sign_request(signature_method, consumer, None)
        return request

    now = time.time()
    params = {'start_time': 0, 'end_time': now}
    params.update(build_request(URL, 'GET'))
    query = "%s?%s" % (URL, urllib.urlencode(params))
    print(query)
    try:
        connection = urllib2.urlopen(query)
        points = json.loads(''.join(connection.readlines()))
        # print(json.dumps(points, indent=4))
    except Exception as e:
        print(e)
    return points

def get_streetviews(points):
    """For each lat/lon pair, pull Google Streetview panorama data and stitch together the choice tiles"""

    if not os.path.isdir("sv_images"):
        os.mkdir("sv_images")    
    for i, point in enumerate(points):    
        print("----------")        
        panoid_url = "http://cbk0.google.com/cbk?output=json&ll=%s,%s" % (point['loc']['lat'], point['loc']['lon'])
        try:
            connection = urllib2.urlopen(panoid_url)
            json_data = json.loads(''.join(connection.readlines()))
            panoid = json_data['Location']['panoId']
        except Exception as e:
            print("JSON download failed: %s" % panoid_url)
            continue            
        url_left = "http://cbk0.google.com/cbk?output=tile&panoid=%s&zoom=3&x=2&y=1" % panoid
        url_right = "http://cbk0.google.com/cbk?output=tile&panoid=%s&zoom=3&x=3&y=1" % panoid
        filepath_left = "sv_images/%s_left.jpg" % i
        filepath_right = "sv_images/%s_right.jpg" % i
        try:
            urllib.urlretrieve(url_left, filepath_left)
            urllib.urlretrieve(url_right, filepath_right)        
        except Exception as e:
            print("Image download failed")
            continue    
        image_left = Image.open(filepath_left)        
        image_right = Image.open(filepath_right)    
        image = Image.new('RGB', (1024, 512))
        image.paste(image_left, (0, 0))
        image.paste(image_right, (512, 0))        
        os.remove(filepath_left)
        os.remove(filepath_right)
        filepath = "sv_images/%s.png" % i
        image.save(filepath, 'PNG')
        print(panoid_url)
        print(url_left)
        print(url_right)                                    
    if not len(points):
        print("No points!")
        exit()                                    
        
def generate_video():
    """Generate a video from the image sequence, using OpenCV"""

    import cv     
    from cv import CV_FOURCC    

    FPS = 30
    IMAGE_FPS = 10
    SIZE = 1024, 512
    FILENAME = "streetview.mov"
    CODEC = CV_FOURCC('M', 'P', '4', '2')
    COLOR = True

    writer = cv.CreateVideoWriter(FILENAME, CODEC, FPS, SIZE, COLOR)
    files = []
    for filename in os.listdir("sv_images"):
        if filename[-4:] != ".png":
            continue
        files.append(filename)
    files.sort(key=alphanum_key)    
    for filename in files:        
        path = "sv_images/%s" % filename
        print(path)
        image = Image.open(path)
        image = pil_to_ipl(image)
        for i in xrange(FPS / IMAGE_FPS):
            cv.WriteFrame(writer, image)
        
def pil_to_ipl(pil_image):
    """Convert a PIL image to ipl (OpenCV)"""    
    import cv
    cv_image = cv.CreateImageHeader(pil_image.size, cv.IPL_DEPTH_8U, 3)
    cv.SetData(cv_image, pil_image.rotate(180).tostring()[::-1])
    return cv_image

def alphanum_key(s):
    """Turn a string into a list of string and number chunks"""
    import re
    return [tryint(c) for c in re.split('([0-9]+)', s)]

def tryint(s):
    try:
        return int(s)
    except:
        return s


if __name__ == "__main__":
    points = get_points()    
    get_streetviews(points)
    generate_video()