config = {
    "ssh": {
        "user": "timelapse",
        "host": "10.0.0.69",
        "path": "~/"
    },
    # Interval in seconds at which images are taken
    "interval": 5,
    # Amount of images allowed in buffer. If the device were to lose connection they would be kept in buffer until connected again. Max size depends on ram available
    "buffer_size": 200
}

import datetime
import logging
import subprocess
import threading
import time

# Images are appended to this list before being uploaded, we store them in a variable to reduce disk writes
image_buffer = []


def main():
    logging.basicConfig(level=logging.DEBUG, format='[%(asctime)s] %(levelname)s: %(message)s', datefmt='%Y-%m-%d %H:%M:%S')
    logging.info("Started")

    t_image_handler = threading.Thread(target=image_handler)
    t_image_handler.start()
    t_image_uploader = threading.Thread(target=image_uploader)
    t_image_uploader.start()

    while True:
        logging.debug(f"[Buffer entries: {len(image_buffer)}] [Active threads: {threading.active_count()}]")

        if len(image_buffer) >= config["buffer_size"]:
            logging.error("Image buffer limit exceeded!!! Connection lost?")
        else:
            subprocess.Popen("termux-camera-photo -c 0 image_buffer_pipe", shell=True)

        time.sleep(config["interval"])


# Appends image recieved from fifo into image_buffer
def image_handler():
    while True:
        # Wait for data to arrive
        with open("image_buffer_pipe", "rb") as binary_file:
            binary_file = binary_file.read()

            # For each file we recieve one that is empty, idk why but we skip it
            if not binary_file:
                continue

            image_buffer.append(
                [
                    datetime.datetime.now(),
                    binary_file
                ]
            )

# Uploads image to remote server then removes image from image_buffer
def image_uploader():
    while True:
        time.sleep(config["interval"])

        while image_buffer:
            # WARNING: I HAVE NO IDEA WHAT I'M DOING
            # Here we pipe the image binary data into ssh and run a remote command. In this case, the remote command is 'cat >filename' which will copy stdin into the 'filename' file
            proc = subprocess.run(
                f"ssh '{config['ssh']['user']}@{config['ssh']['host']}' 'cat >{config['ssh']['path']}{image_buffer[0][0].strftime('%Y%m%d_%H%M%S_%f')}.jpg'",
                stdout=subprocess.PIPE,
                input=image_buffer[0][1],
                encoding=None,
                shell=True
            )
            if proc.returncode == 0:
                image_buffer.pop(0)
            else:
                logging.error(f"Command 'SSH' returned non-zero exit status {proc.returncode}")
                break


if __name__ == "__main__":
    main()