import os
import signal
import subprocess
import sqlite3
import time
import json

get_active_video_sql = r'''
SELECT video_url, video_arguments, button_name FROM buttons
WHERE is_active = 1
LIMIT 1
'''

def play_video(previous_process, video_player_path, player_arguments, video_url, env):
    if not previous_process is None:
        os.killpg(os.getpgid(previous_process.pid), signal.SIGTERM)

    return subprocess.Popen(
        "{video_player} {arguments} {video_url}".format(
            video_player = video_player_path,
            arguments = player_arguments,
            video_url = video_url
        ),
        stdout = subprocess.PIPE,
        stderr = subprocess.PIPE,
        shell = True,
        preexec_fn = os.setsid,
        env = env
    )

def get_active_video(db):
    cursor = db.execute(get_active_video_sql)
    return cursor.fetchall()[0]

with open("config.json", "r") as config_file:
    config_json = json.loads(config_file.read())

my_env = os.environ.copy()
my_env["DISPLAY"] = config_json["display_config"]

current_process = None
current_video = None
db = sqlite3.connect(config_json["db_name"])

while True:
    active_video = get_active_video(db)

    if current_video is None or current_video[2] != active_video[2]:
        current_video = active_video

        if current_video[2] == config_json["disabled_name"] and not current_process is None:
            os.killpg(os.getpgid(current_process.pid), signal.SIGTERM)
            current_process = None
        else:
            current_process = play_video(
                current_process,
                config_json["video_tool"],
                current_video[0],
                current_video[1],
                my_env
            )

    time.sleep(1)