#!/usr/bin/python3

import PIL.Image
import sys, io, os
import datetime
import asyncio
import aiohttp
import json

# how many frames to skip
#  1 means none
#  2 means that every second frame gets captured
#  3 means every third
#  [...]
frameskip = 1

canvases = [
        {
            "canvas_name": "earth",
            "canvas_size": 256*256,
            "canvas_id": 0,
            "bkg": (202, 227, 255),
        },
        {
            "canvas_name": "moon",
            "canvas_size": 4096,
            "canvas_id": 1,
            "bkg": (49, 46, 47),
        },
        {
        }   ,
        {
            "canvas_name": "corona",
            "canvas_size": 256,
            "canvas_id": 3,
            "bkg": (33, 28, 15),
        },
        {
            "canvas_name": "compass",
            "canvas_size": 1024,
            "canvas_id": 4,
            "bkg": (196, 196, 196),
        },
        {
        },
        {
        },
        {
            "canvas_name": "1bit",
            "canvas_size": 4096,
            "canvas_id": 7,
            "bkg": (0, 0, 0),
        },
    ]

async def fetch(session, url, offx, offy, image, bkg, needed = False):
    attempts = 0
    while True:
        try:
            async with session.get(url) as resp:
                if resp.status == 404:
                    if needed:
                        img = PIL.Image.new('RGB', (256, 256), color=bkg)
                        image.paste(img, (offx, offy))
                        img.close()
                    return
                if resp.status != 200:
                    if needed:
                        continue
                    return
                data = await resp.read()
                img = PIL.Image.open(io.BytesIO(data)).convert('RGBA')
                image.paste(img, (offx, offy), img)
                img.close()
                return
        except:
            if attempts > 3:
                raise
            attempts += 1
            pass

async def get_area(canvas, x, y, w, h, start_date, end_date):
    canvas_data = canvases[canvas]
    canvas_id = canvas_data["canvas_id"]
    canvas_size = canvas_data["canvas_size"]
    bkg = canvas_data["bkg"]

    offset = int(-canvas_size / 2)
    xc = (x - offset) // 256
    wc = (x + w - offset) // 256
    yc = (y - offset) // 256
    hc = (y + h - offset) // 256
    print("Load from %s / %s to %s / %s" % (xc, yc, wc + 1, hc + 1))
    delta = datetime.timedelta(days=1)
    end_date = end_date.strftime("%Y%m%d")
    iter_date = None
    cnt = 0
    #frames = []
    previous_day = PIL.Image.new('RGB', (w, h), color=bkg)
    while iter_date != end_date:
        iter_date = start_date.strftime("%Y%m%d")
        print('------------------------------------------------')
        print('Getting frames for date %s' % (iter_date))
        start_date = start_date + delta
        tasks = []
        async with aiohttp.ClientSession() as session:
            image = PIL.Image.new('RGBA', (w, h))
            for iy in range(yc, hc + 1):
                for ix in range(xc, wc + 1):
                    url = 'https://storage.pixelplanet.fun/%s/%s/tiles/%s/%s.png' % (iter_date, canvas_id, ix, iy)
                    offx = ix * 256 + offset - x
                    offy = iy * 256 + offset - y
                    tasks.append(fetch(session, url, offx, offy, image, bkg, True))
            await asyncio.gather(*tasks)
            print('Got start of day')
            # check if image is all just one color to lazily detect if whole full backup was 404
            clr = image.getcolors(1)
            if clr is not None:
                print("Got faulty full-backup frame, using last frame from previous day instead.")
                image = previous_day.copy()
            cnt += 1
            #frames.append(image.copy())
            image.save('./timelapse/t%s.png' % (cnt))
            while True:
                async with session.get('https://pixelplanet.fun/api/history?day=%s&id=%s' % (iter_date, canvas_id)) as resp:
                    try:
                        time_list = json.loads(await resp.text())
                        break
                    except:
                        print('Couldn\'t decode json for day %s, trying again' % (iter_date))
            i = 0
            for time in time_list:
                i += 1
                if (i % frameskip) != 0:
                    continue
                if time == '0000':
                    # 0000 incremential backups are faulty
                    continue
                tasks = []
                image_rel = image.copy()
                for iy in range(yc, hc + 1):
                    for ix in range(xc, wc + 1):
                        url = 'https://storage.pixelplanet.fun/%s/%s/%s/%s/%s.png' % (iter_date, canvas_id, time, ix, iy)
                        offx = ix * 256 + offset - x
                        offy = iy * 256 + offset - y
                        tasks.append(fetch(session, url, offx, offy, image_rel, bkg))
                await asyncio.gather(*tasks)
                print('Got time %s' % (time))
                cnt += 1
                #frames.append(image.copy())
                image_rel.save('./timelapse/t%s.png' % (cnt))
                if time == time_list[-1]:
                    # if last element of day, copy it to previous_day to reuse it when needed
                    print("Remembering last frame of day.")
                    previous_day.close()
                    previous_day = image_rel.copy();
                image_rel.close()
            image.close()
    previous_day.close()
    # this would save a gif right out of the script, but giffs are huge and not good
    #frames[0].save('timelapse.png', save_all=True, append_images=frames[1:], duration=100, loop=0, default_image=False, blend=1)


if __name__ == "__main__":
    if len(sys.argv) != 5 and len(sys.argv) != 6:
        print("Download history of an area of pixelplanet - useful for timelapses")
        print("")
        print("Usage:    historyDownload.py canvasId startX_startY endX_endY start_date [end_date]")
        print("")
        print("→start_date and end_date are in YYYY-MM-dd formate")
        print("→user R key on pixelplanet to copy coordinates)")
        print("→images will be saved into timelapse folder)")
        print("-----------")
        print("You can create a timelapse from the resulting files with ffmpeg like that:")
        print("ffmpeg -framerate 15 -f image2 -i timelapse/t%d.png -c:v libvpx-vp9 -pix_fmt yuva420p output.webm")
        print("or lossless example:")
        print("ffmpeg -framerate 15 -f image2 -i timelapse/t%d.png -c:v libvpx-vp9 -pix_fmt yuv444p -qmin 0 -qmax 0 -lossless 1 -an output.webm")
    else:
        canvas = int(sys.argv[1])
        start = sys.argv[2].split('_')
        end = sys.argv[3].split('_')
        start_date = datetime.date.fromisoformat(sys.argv[4])
        if len(sys.argv) == 6:
            end_date = datetime.date.fromisoformat(sys.argv[5])
        else:
            end_date = datetime.date.today()
        x = int(start[0])
        y = int(start[1])
        w = int(end[0]) - x + 1
        h = int( end[1]) - y + 1
        loop = asyncio.get_event_loop()
        if not os.path.exists('./timelapse'):
            os.mkdir('./timelapse')
        loop.run_until_complete(get_area(canvas, x, y, w, h, start_date, end_date))
        print("Done!")
        print("to create a timelapse from it:")
        print("ffmpeg -framerate 15 -f image2 -i timelapse/t%d.png -c:v libvpx-vp9 -pix_fmt yuva420p output.webm")
        print("example with scaling *3 and audio track:")
        print("ffmpeg -i ./audio.mp3 -framerate 8 -f image2 -i timelapse/t%d.png -map 0:a -map 1:v -vf scale=iw*3:-1 -shortest -c:v libvpx-vp9 -c:a libvorbis -pix_fmt yuva420p output.webm")
        print("lossless example:")
        print("ffmpeg -framerate 15 -f image2 -i timelapse/t%d.png -c:v libvpx-vp9 -pix_fmt yuv444p -qmin 0 -qmax 0 -lossless 1 -an output.webm")