#!/usr/bin/env python3

import feedparser
import subprocess
import os
import sys
import time
import json
import uuid
import errno
import signal
import transmissionrpc
import requests
import urllib.parse

from domain import url_extract_domain
import episode

from lxml import etree
from datetime import datetime

script_dir = os.path.dirname(os.path.realpath(sys.argv[0]))

config_dir = os.path.expanduser("~/.config/automedia")
rss_config_dir = os.path.join(config_dir, "rss")
html_config_dir = os.path.join(config_dir, "html")
automedia_pid_path = "/tmp/automedia.pid"

only_show_finished_notification = True

class TrackedRss:
    title = None
    link = None
    json_data = None

    def __init__(self, title, link, json_data):
        self.title = title
        self.link = link
        self.json_data = json_data

class TrackedHtml:
    title = None
    link = None
    plugin = None
    json_data = None

    def __init__(self, title, link, plugin, json_data):
        self.title = title
        self.link = link
        self.plugin = plugin
        self.json_data = json_data

class TorrentProgress:
    id = None
    name = None
    progress = None

    def __init__(self, id, name, progress):
        self.id = id
        self.name = name
        self.progress = progress

class HtmlItemProgress:
    name = None
    finished = None

    def __init__(self, name, finished):
        self.name = name
        self.finished = finished

def get_file_content_or_none(path):
    try:
        with open(path, "r") as file:
            return file.read()
    except FileNotFoundError:
        return None

def get_tracked_rss_by_title(tracked_rss, title):
    for t in tracked_rss:
        if t.title == title:
            return t
    return None

def get_tracked_rss(rss_tracked_dir, existing_tracked_rss):
    try:
        tracked_rss = []
        for title in os.listdir(rss_tracked_dir):
            # Check if we already have the data for the title
            #if get_tracked_rss_by_title(existing_tracked_rss, title):
            #    continue

            in_progress = get_file_content_or_none(os.path.join(rss_tracked_dir, title, ".in_progress"))
            if in_progress:
                print("Skipping in-progress rss %s" % title)
                continue
            link = get_file_content_or_none(os.path.join(rss_tracked_dir, title, "link"))
            json_data = get_file_content_or_none(os.path.join(rss_tracked_dir, title, "data"))
            if json_data:
                json_data = json.loads(json_data)
            else:
                updated = str(time.time())
                json_data = {
                    "link": link,
                    "updated": updated,
                    "downloaded": []
                }
            if not link or not json_data:
                print("Rss corrupt, link or data missing for rss %s" % title)
                continue
            tracked_rss.append(TrackedRss(title, link, json_data))
        return tracked_rss
    except FileNotFoundError:
        return []

def rss_update_latest(rss_tracked_dir, rss, latest, url, filename):
    updated = str(time.time())
    with open(os.path.join(rss_tracked_dir, rss.title, "updated"), "w") as file:
        file.write(updated)

    rss.json_data["updated"] = updated
    rss.json_data["downloaded"].append({ "title": latest, "filename": filename, "time": updated, "url": url })
    with open(os.path.join(rss_tracked_dir, rss.title, "data"), "w") as file:
        json.dump(rss.json_data, file, indent=4)

def html_update_latest(html_tracked_dir, html, latest, url):
    updated = str(time.time())
    with open(os.path.join(html_tracked_dir, html.title, "updated"), "w") as file:
        file.write(updated)

    html.json_data["updated"] = updated
    html.json_data["downloaded"].append({ "title": latest, "time": updated, "url": url })
    with open(os.path.join(html_tracked_dir, html.title, "data"), "w") as file:
        json.dump(html.json_data, file, indent=4)

def get_tracked_html(html_tracked_dir):
    try:
        tracked_html = []
        for title in os.listdir(html_tracked_dir):
            in_progress = get_file_content_or_none(os.path.join(html_tracked_dir, title, ".in_progress"))
            if in_progress:
                print("Skipping in-progress html %s" % title)
                continue
            link = get_file_content_or_none(os.path.join(html_tracked_dir, title, "link"))
            if not link:
                print("html corrupt, link missing for html %s" % title)
                continue
            plugin = get_file_content_or_none(os.path.join(html_tracked_dir, title, "plugin"))
            json_data = get_file_content_or_none(os.path.join(html_tracked_dir, title, "data"))
            if json_data:
                json_data = json.loads(json_data)
            else:
                updated = str(time.time())
                json_data = {
                    "plugin": plugin,
                    "link": link,
                    "updated": updated,
                    "downloaded": []
                }
            if not plugin or not json_data:
                print("html corrupt, plugin or data missing for html %s" % title)
                continue
            tracked_html.append(TrackedHtml(title, link, plugin, json_data))
        return tracked_html
    except FileNotFoundError:
        return []

# @urgency should either be "low", "normal" or "critical"
def show_notification(title, body, urgency="normal"):
    subprocess.Popen(["notify-send", "-u", urgency, "--", title, body])

def is_torrent_daemon_running():
    process = subprocess.Popen(["transmission-remote", "-si"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    process.communicate()
    return process.returncode == 0

def start_torrent_daemon(download_dir):
    # TODO: Make seed ratio configurable
    process = subprocess.Popen(["transmission-daemon", "--global-seedratio", "2.0", "--download-dir", download_dir])
    process.communicate()
    while not is_torrent_daemon_running():
        time.sleep(0.1)
    return process.returncode == 0

def add_torrent(torrent_link, tc):
    try:
        return tc.add_torrent(torrent_link)
    except transmissionrpc.TransmissionError as e:
        show_notification("Download failed", "Failed to download torrent: {}, Error: {}".format(torrent_link, str(e)), urgency="critical")
        return None

def get_torrent_progress(tc):
    torrent_progress = []
    for torrent in tc.get_torrents():
        torrent_progress.append(TorrentProgress(torrent.id, torrent.name, torrent.progress))
    return torrent_progress

def get_finished_torrents(torrents):
    filtered_torrents = []
    for torrent in torrents:
        if abs(100.0 - torrent.progress) <= 0.001:
            filtered_torrents.append(torrent)
    return filtered_torrents

def get_unfinished_torrents(torrents):
    filtered_torrents = []
    for torrent in torrents:
        if abs(100.0 - torrent.progress) > 0.001:
            filtered_torrents.append(torrent)
    return filtered_torrents

def get_matching_torrents_by_name(torrents1, torrents2):
    matching_torrents = []
    for torrent1 in torrents1:
        for torrent2 in torrents2:
            if torrent1.id == torrent2.id:
                matching_torrents.append(torrent1.name)
    return matching_torrents

def get_rss_from_episode_info(episode_name_raw, episode_info):
    submitter_query_text = ''
    if episode_info.group_name:
        submitter_query_text = 'Enter the name of the submitter (leave empty to choose "%s", or type "anon" to choose all submitters): ' % episode_info.group_name
    else:
        submitter_query_text = 'Enter the name of the submitter (type anon to choose all submitters): '

    selected_submitter = None
    while True:
        response = input(submitter_query_text)
        if response == "anon":
            break
        elif len(response) > 0 or (len(response) == 0 and episode_info.group_name):
            if len(response) == 0:
                response = episode_info.group_name
            group_name_escaped = urllib.parse.quote(response)
            user_page_response = requests.head("https://nyaa.si/user/" + group_name_escaped)
            if user_page_response.ok:
                selected_submitter = response
                break
            else:
                print('The submitter "%s" doesn\'t exist on nyaa.si, please choose another submitter.' % response)
    
    generic_name = episode_info.get_generic_name()
    while True:
        response = input('Are you sure you want to track "%s" by %s after "%s" ? (Y)es/No: ' % (generic_name, '"%s"' % selected_submitter if selected_submitter else "all submitters", episode_name_raw))
        if len(response) > 0 and response[0].lower() == 'n':
            return None
        elif len(response) == 0 or response[0].lower() == 'y':
            break

    nyaa_rss = 'https://nyaa.si/?page=rss&q={}&c=0_0&f=0'.format(urllib.parse.quote(generic_name))
    if selected_submitter:
        nyaa_rss += '&u={}'.format(urllib.parse.quote(selected_submitter))
    return nyaa_rss

def add_rss(name, url, rss_config_dir, start_after):
    feed = feedparser.parse(url)
    if feed.bozo == 1:
        episode_info = episode.episode_extract_info(url)
        if not episode_info.group_name or not episode_info.anime_name:
            print("Failed to add rss, error: {}".format(str(feed.bozo_exception)))
            return False

        start_after = url
        url = get_rss_from_episode_info(url, episode_info)
        if not url:
            return True

        feed = feedparser.parse(url)
        if feed.bozo == 1:
            print("Failed to add rss, error: {}".format(str(feed.bozo_exception)))
            return False
        
    if not name:
        name = feed["channel"]["title"].replace("/", "_").strip()

    if not name or len(name) == 0:
        print("Name not provided and name in rss is empty")
        return False

    start_after_url = None
    found_start_after = False
    for item in feed["items"]:
        title = item["title"].replace("/", "_").strip()
        if start_after and title == start_after:
            found_start_after = True
            start_after_url = item["link"]
            break
    
    if start_after and not found_start_after:
        print("Failed to find %s in rss %s" % (start_after, url))
        return False

    name = name.replace("/", "_")
    rss_dir = os.path.join(rss_config_dir, "tracked", name)
    os.makedirs(rss_dir)

    # Create an ".in_progress" file to prevent periodic sync from reading rss data
    # before we have finished adding all the data.
    # Timestamp is added to it to make it possible to automatically cleanup rss that is corrupted
    # (for example if the computer crashes before the in_progress file is removed).
    in_progress_filepath = os.path.join(rss_dir, ".in_progress")
    with open(in_progress_filepath, "w") as file:
        file.write(str(time.time()))

    with open(os.path.join(rss_dir, "link"), "w") as file:
        file.write(url)

    updated = str(time.time())
    with open(os.path.join(rss_dir, "updated"), "w") as file:
        file.write(updated)

    data = {
        "link": url,
        "updated": updated,
        "downloaded": []
    }
    if start_after:
        data["downloaded"].append({ "title": start_after, "time": updated, "url": start_after_url })

    with open(os.path.join(rss_dir, "data"), "w") as file:
        json.dump(data, file, indent=4)
    
    os.remove(in_progress_filepath)
    return True

def add_html(name, url, html_config_dir, start_after):
    domain = url_extract_domain(url)
    if len(domain) == 0:
        print("Invalid url: {}".format(url))
        return False
    domain_plugin_path = os.path.join(script_dir, "plugins", domain)
    domain_plugin_py_path = os.path.join(script_dir, "plugins", domain + ".py")

    plugin_path = None
    if os.path.isfile(domain_plugin_path):
        plugin_path = domain_plugin_path
    elif os.path.isfile(domain_plugin_py_path):
        plugin_path = domain_plugin_py_path
    else:
        print("Plugin doesn't exist: {}".format(domain))
        return False

    if not name or len(name) == 0:
        print("Name not provided or empty")
        return False
 
    start_after_url = None
    if start_after:
        items = plugin_list(plugin_path, url, None)
        if items is None:
            return False

        found_start_after = False
        for item in reversed(items):
            title = item["name"].replace("/", "_").strip()
            if start_after and title == start_after:
                found_start_after = True
                start_after_url = item["url"]
                break

        if not found_start_after:
            print("Failed to find %s in html %s" % (start_after, url))
            return False

    name = name.replace("/", "_")
    html_dir = os.path.join(html_config_dir, "tracked", name)
    os.makedirs(html_dir)

    # Create an ".in_progress" file to prevent periodic sync from reading rss data
    # before we have finished adding all the data.
    # Timestamp is added to it to make it possible to automatically cleanup rss that is corrupted
    # (for example if the computer crashes before the in_progress file is removed).
    in_progress_filepath = os.path.join(html_dir, ".in_progress")
    with open(in_progress_filepath, "w") as file:
        file.write(str(int(time.time())))

    with open(os.path.join(html_dir, "link"), "w") as file:
        file.write(url)

    with open(os.path.join(html_dir, "plugin"), "w") as file:
        file.write(os.path.basename(plugin_path))

    updated = str(time.time())
    with open(os.path.join(html_dir, "updated"), "w") as file:
        file.write(updated)

    data = {
        "plugin": os.path.basename(plugin_path),
        "link": url,
        "updated": updated,
        "downloaded": []
    }
    if start_after:
        data["downloaded"].append({ "title": start_after, "time": updated, "url": start_after_url })

    with open(os.path.join(html_dir, "data"), "w") as file:
        json.dump(data, file, indent=4)
    
    os.remove(in_progress_filepath)
    return True

def get_downloaded_item_by_title(tracked_rss, title):
    for item in tracked_rss.json_data["downloaded"]:
        if item.title == title:
            return item
    return None

# Return the title of the newest item
def sync_rss(tracked_rss, tc):
    rss_tracked_dir = os.path.join(rss_config_dir, "tracked")
    feed = feedparser.parse(tracked_rss.link)
    if feed.bozo == 1:
        print("{}: Failed to sync rss for url {}, error: {}".format(str(datetime.today().isoformat()), tracked_rss.link, str(feed.bozo_exception)))
        if not only_show_finished_notification:
            show_notification("RSS Sync failed", "Failed to parse rss for url {}, error: {}".format(tracked_rss.link, str(feed.bozo_exception)), urgency="critical")
        return None

    seen_titles = set()
    seen_urls = set()
    for downloaded_item in tracked_rss.json_data["downloaded"]:
        seen_titles.add(downloaded_item["title"].lower().replace(" ", ""))
        seen_urls.add(downloaded_item.get("url", ""))

    items = []
    for item in feed["items"]:
        title = item["title"].replace("/", "_").strip()
        link = item["link"]
        # TODO: Goto next page in rss if supported, if we cant find our item on the first page
        #if not get_downloaded_item_by_title(tracked_rss, title):
        if title.lower().replace(" ", "") in seen_titles or link in seen_urls:
            break
        items.append(item)

    # Add torrents from the oldest to the newest, and stop when failing to add torrent.
    # If it fails, there will be an attempt to add them again after next sync cycle.
    latest = None
    for item in reversed(items):
        title = item["title"].replace("/", "_").strip()
        link = item["link"]

        torrent = add_torrent(link, tc)
        if not torrent:
            show_notification("RSS Sync failed", "Failed to add torrent: {}".format(link), urgency="critical")
            return latest

        rss_update_latest(rss_tracked_dir, tracked_rss, title, link, torrent.name)
        latest = title

        if not only_show_finished_notification:
            show_notification("Download started", latest)
    return latest

def plugin_list(plugin_path, url, latest):
    if not latest:
        latest = []

    plugin_name = os.path.basename(plugin_path)
    process = None
    try:
        process = subprocess.Popen([plugin_path, "list", url], stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
    except FileNotFoundError as e:
        print("{}: Plugin failed: Failed to launch plugin list for plugin {}, error: {}".format(str(datetime.today().isoformat()), plugin_name, str(e)))
        return None

    stdout, stderr = process.communicate(json.dumps(latest).encode())
    if process.returncode != 0:
        print("{}: Plugin failed: Failed to launch plugin list for plugin {} and url {}, error: stdout: {}, stderr: {}".format(str(datetime.today().isoformat()), plugin_name, url, stdout.decode('utf-8'), stderr.decode('utf-8')))
        if not only_show_finished_notification:
            show_notification("Plugin failed", "Failed to launch plugin list for plugin {} and url {}, error: stdout: {}, stderr: {}".format(plugin_name, url, stdout.decode('utf-8'), stderr.decode('utf-8')), urgency="critical")
        return None

    try:
        return json.loads(stdout.decode('utf-8'))
    except json.decoder.JSONDecodeError as e:
        if not only_show_finished_notification:
            show_notification("Plugin failed", "Failed to json decode response of plugin {}, error: {}".format(plugin_name, str(e)), urgency="critical")
        return None

# TODO: Make asynchronous?
def plugin_download(plugin_path, url, download_dir):
    process = subprocess.Popen([plugin_path, "download", url, download_dir], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    process.communicate()
    return process.returncode == 0

def resume_tracked_html(plugin_entry, download_dir, tracked_html, session_id):
    # TODO: Instead of redownloading, add resuming. This could be done by adding the files that have been downloaded to a file.
    # Redownload items we can detect have stopped. This can happen if the computer crashes or loses connection while downloading.
    title_dir = os.path.join(download_dir, tracked_html.title)
    try:
        for item in os.listdir(title_dir):
            item_dir = os.path.join(title_dir, item)
            if os.path.isfile(os.path.join(item_dir, ".finished")):
                continue
            
            in_progress_path = os.path.join(item_dir, ".in_progress")
            url = get_file_content_or_none(in_progress_path)
            # Item has finished downloading
            if not url:
                continue

            invalid_session = False
            try:
                with open(os.path.join(item_dir, ".session_id"), "r") as file:
                    item_session_id = file.read()
                    if item_session_id != session_id:
                        invalid_session = True
            except FileNotFoundError as e:
                invalid_session = True
            
            if invalid_session:
                #if not only_show_finished_notification:
                show_notification("Resuming", "Resuming download for item {} with plugin {}".format(os.path.join(tracked_html.title, item), tracked_html.plugin))
                with open(os.path.join(item_dir, ".session_id"), "w") as file:
                    file.write(session_id)
                plugin_download(plugin_entry, url, item_dir)

    except FileNotFoundError as e:
        pass

def build_plugin_list_input(tracked_html):
    result = []
    for downloaded_item in tracked_html.json_data["downloaded"]:
        result.append({ "title": downloaded_item["title"], "url": downloaded_item.get("url", "") })
    return result

# Return the title of the newest item
def sync_html(tracked_html, download_dir, session_id):
    plugin_entry = os.path.join(script_dir, "plugins", tracked_html.plugin)
    resume_tracked_html(plugin_entry, download_dir, tracked_html, session_id)
    html_tracked_dir = os.path.join(html_config_dir, "tracked")

    # The program takes and index starting from 1, which is the chapter number

    # Program should print the names of each item (chapter for manga) after "latest", sorted by newest to oldest
    # along with the urls to them.
    # Only get the items before the one called @latest. The printed data should be in this json format:
    #   [
    #     {
    #       "name": "Example name",
    #       "url": "https://example.com"
    #     },
    #     {
    #       "name": "Another item",
    #       "url": "https://another.url.com"
    #     }
    #   ]
    # ./program list url latest
    # Note: @latest argument here is optional
    items = plugin_list(plugin_entry, tracked_html.link, build_plugin_list_input(tracked_html))
    if not items:
        return None

    # A file called ".in_progress" should be added to the download directory when the download is in progress.
    # The ".in_progress" file should contain the url that was used to download the item.
    # A file called ".finished" should be added to the download directory when the download has finished.
    # ./program download url download_dir
    latest = None
    for item in reversed(items):
        url = item["url"]
        name = item["name"].replace("/", "_").strip()
        item_dir = os.path.join(download_dir, tracked_html.title, name)
        os.makedirs(item_dir, exist_ok=True)

        with open(os.path.join(item_dir, ".session_id"), "w") as file:
            file.write(session_id)

        if not plugin_download(plugin_entry, url, item_dir):
            return latest

        html_update_latest(html_tracked_dir, tracked_html, name, url)

        latest = name
        show_notification("Download finished", "{}/{}".format(tracked_html.title, name))
    return latest

def sync(rss_config_dir, html_config_dir, download_dir, sync_rate_sec):
    os.makedirs(download_dir, exist_ok=True)
    if not is_torrent_daemon_running():
        if not start_torrent_daemon(download_dir):
            print("Failed to start torrent daemon")
            exit(2)
        print("Started torrent daemon with download directory {}".format(download_dir))

    rss_tracked_dir = os.path.join(rss_config_dir, "tracked")
    html_tracked_dir = os.path.join(html_config_dir, "tracked")
    # This is also check rate for html items
    check_torrent_status_rate_sec = 15
    unfinished_torrents = []

    # TODO: Remove this and keep a list of "in progress" html items in memory instead.
    session_id = uuid.uuid4().hex

    tc = transmissionrpc.Client("127.0.0.1")
    
    running = True
    tracked_rss = []
    while running:
        tracked_rss = get_tracked_rss(rss_tracked_dir, tracked_rss)
        for rss in tracked_rss:
            print("{}: rss: Syncing {}".format(str(datetime.today().isoformat()), rss.title))
            sync_rss(rss, tc)
            # Add last synced timestamp. This together with "updated" file is used to remove series
            # that haven't updated in a long time (either finished series or axes series)

            # TODO: Fix. This will fail if the path is removed while its running,
            # same with other places.
            # To fix, add a command to remove tracked items safely
            with open(os.path.join(rss_tracked_dir, rss.title, "synced"), "w") as file:
                file.write(str(time.time()))
            #else:
            #    print("No 'latest' item found for rss (maybe we already have the latest item?) %s" % rss.title)
            #time.sleep(0.5) # Sleep between fetching rss so we don't get banned for spamming

        tracked_html = get_tracked_html(html_tracked_dir)
        for html in tracked_html:
            print("{}: html({}): Syncing {}".format(str(datetime.today().isoformat()), html.plugin, html.title))
            sync_html(html, download_dir, session_id)
            # Add last synced timestamp. This together with "updated" file is used to remove series
            # that haven't updated in a long time (either finished series or axes series)
            with open(os.path.join(html_tracked_dir, html.title, "synced"), "w") as file:
                file.write(str(time.time()))
            #else:
            #    print("No 'latest' item found for html (maybe we already have the latest item?) %s" % html.title)
            #time.sleep(0.5) # Sleep between fetching html so we don't get banned for spamming
        
        # Check torrent status with sleeping until it's time to sync rss
        count = 0
        while count < sync_rate_sec/check_torrent_status_rate_sec:
            torrents = get_torrent_progress(tc)
            finished_torrents = get_finished_torrents(torrents)
            newly_finished_torrents = get_matching_torrents_by_name(finished_torrents, unfinished_torrents)
            for newly_finished_torrent in newly_finished_torrents:
                show_notification("Download finished", newly_finished_torrent)
            unfinished_torrents = get_unfinished_torrents(torrents)

            time.sleep(check_torrent_status_rate_sec)
            count += 1

def usage():
    print("usage: automedia.py COMMAND")
    print("")
    print("COMMANDS")
    print("  add           Add media to track")
    print("  sync          Start syncing tracked media")
    print("  downloaded    List downloaded media")
    exit(1)

def usage_add():
    print("usage: automedia.py add <type> <url|filename> [--name name] [--start-after start_after]")
    print("OPTIONS")
    print("  type             The type should be either rss or html")
    print("  url              The url to the rss or html")
    print("  filename         The filename of an episode of an existing serie to start track. Currently only works with rss on https://nyaa.si")
    print("  --name           The display name to be used for the media. Optional for rss, in which case the name will be retries from rss TITLE, required for html")
    print("  --start-after    The sync should start downloading media after this item. This --start-after value should be the title of the episode/chapter (Optional, default is to start from the first item)")
    print("EXAMPLES")
    print("  automedia.py add rss 'https://nyaa.si/?page=rss&q=Tejina-senpai+1080p&c=0_0&f=0&u=HorribleSubs'")
    print("  automedia.py add html 'https://manganelo.com/manga/read_naruto_manga_online_free3' --name Naruto")
    print("  automedia.py add rss '[Erai-raws] Saiki Kusuo no Psi Nan - Kanketsu-hen - 01 [1080p][Multiple Subtitle].mkv'")
    exit(1)

def usage_sync():
    print("usage: automedia.py sync <download_dir>")
    print("OPTIONS")
    print("  download_dir    The path where media should be downloaded to")
    print("EXAMPLES")
    print("  automedia.py sync /home/adam/Downloads/automedia")
    exit(1)

def command_add(args):
    if len(args) < 2:
        usage_add()

    media_type = args[0]
    media_url = args[1]
    media_name = None
    start_after = None

    option = None
    for arg in args[2:]:
        if arg in [ "--name", "--start-after"]:
            if option:
                usage_add()
            option = arg
        else:
            if not option:
                usage_add()

            if option == "--name":
                media_name = arg
            elif option == "--start-after":
                start_after = arg
            else:
                print("Invalid option %s" % option)
                usage_add()
            option = None

    if start_after:
        start_after = start_after.replace("/", "_").strip()

    media_url = media_url.strip()

    if media_type == "rss":
        os.makedirs(rss_config_dir, exist_ok=True)
        result = add_rss(media_name, media_url, rss_config_dir, start_after)
        if not result:
            exit(2)
    elif media_type == "html":
        if not media_name:
            print("missing --name for media of type 'html'")
            usage_add()

        os.makedirs(html_config_dir, exist_ok=True)
        result = add_html(media_name, media_url, html_config_dir, start_after)
        if not result:
            exit(2)
    else:
        print("type should be either rss or html")
        usage_add()

def command_sync(args):
    if len(args) < 1:
        usage_sync()

    download_dir = args[0]
    if not download_dir:
        usage_sync()

    pid_file = None
    while True:
        try:
            pid_file = os.open(automedia_pid_path, os.O_CREAT | os.O_EXCL | os.O_WRONLY)
            break
        except OSError as e:
            if e.errno != errno.EEXIST:
                raise

            running_automedia_pid = get_file_content_or_none(automedia_pid_path)
            if running_automedia_pid:
                cmdline = get_file_content_or_none("/proc/%s/cmdline" % running_automedia_pid)
                if cmdline and "automedia.py" in cmdline and "sync" in cmdline:
                    print("AutoMedia is already running with sync")
                    exit(0)
            os.remove(automedia_pid_path)

    def signal_handler(signum, frame):
        os.unlink(automedia_pid_path)
        exit(1)
    signal.signal(signal.SIGINT, signal_handler)

    os.write(pid_file, ("%s" % os.getpid()).encode())
    os.close(pid_file)

    os.makedirs(rss_config_dir, exist_ok=True)
    os.makedirs(html_config_dir, exist_ok=True)

    sync_rate_sec = 15 * 60 # every 15 min
    sync(rss_config_dir, html_config_dir, download_dir, sync_rate_sec)

def data_file_get_downloaded(data_filepath):
    downloaded = []
    try:
        with open(data_filepath, "r") as file:
            for item in json.loads(file.read())["downloaded"]:
                downloaded.append(item)
    except OSError:
        pass
    return downloaded

def get_downloaded_items(tracked_dir, is_html):
    downloaded_items = []
    try:
        downloaded_items = []
        for name in os.listdir(tracked_dir):
            data_filepath = os.path.join(tracked_dir, name, "data")
            downloaded = data_file_get_downloaded(data_filepath)
            for item in downloaded:
                if item.get("time"):
                    if is_html:
                        item["title"] = os.path.join(name, item["title"])
                    filename = item.get("filename")
                    if filename:
                        item["title"] = filename
                    downloaded_items.append(item)
    except OSError:
        pass
    return downloaded_items

def command_downloaded():
    downloaded_items = []
    downloaded_items.extend(get_downloaded_items(os.path.join(rss_config_dir, "tracked"), False))
    downloaded_items.extend(get_downloaded_items(os.path.join(html_config_dir, "tracked"), True))
    downloaded_items = sorted(downloaded_items, key=lambda item: float(item["time"]))
    for item in downloaded_items:
        print(item["title"])

def main():
    if len(sys.argv) < 2:
        usage()

    command = sys.argv[1]
    if command == "add":
        command_add(sys.argv[2:])
    elif command == "sync":
        command_sync(sys.argv[2:])
    elif command == "downloaded":
        command_downloaded()
    else:
        usage()

if __name__ == "__main__":
    main()