#!/usr/bin/env python

# Copyright (c) 2025-2026 bleach86

# 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 the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# You can download the latest version of this tool from:
# https://github.com/bleach86/mister_cloud_saves


import os
import sys
import signal
import subprocess
import configparser
import shutil
import time
import hashlib
import requests  # type: ignore

DEFAULT_SERVER_URL = "https://mister-cloud-saves.tuxprint.com"
GH_REPO_API_URL = (
    "https://api.github.com/repos/bleach86/mister_cloud_saves/releases/latest"
)

RAW_URL_BASE = "https://raw.githubusercontent.com/bleach86/mister_cloud_saves"
SCRIPT_RAW_URL = f"{RAW_URL_BASE}/refs/heads/main/scripts/cloud_saves.sh"
UPDATE_DB_RAW_URL = (
    f"{RAW_URL_BASE}_update_db/refs/heads/main/mister_cloud_saves_db.json"
)
LAUNCHER_SCRIPT_URL = f"{RAW_URL_BASE}/refs/heads/main/scripts/cloud_saves_launcher.sh"
MISTER_PATH = "/media/fat"
CLIENT_DIR = os.path.join(MISTER_PATH, "cloud_saves")
MISTER_LINUX_DIR = os.path.join(MISTER_PATH, "linux/")


def get_user_id(server_url):
    """
    Takes server_url as parameter to request a new user ID if config does not exist.

    :return: User ID
    """

    if is_config_existing():
        config = read_config()
        return config.get("User", "user_id")

    response = requests.get(f"{server_url}/generate_user_id", timeout=30)
    if response.status_code == 200:
        return response.text.strip()

    print("Error generating user ID")
    sys.exit(1)


def get_server_url():
    """
    Gets server URL from config or prompts user for it.

    :return: Server URL
    """

    if is_config_existing():

        config = read_config()
        return config.get("Server", "server_url")

    while True:
        print("The default server URL is:", DEFAULT_SERVER_URL)
        user_input = input("Enter server URL or press Enter to use default: ").strip()

        if user_input == "":
            return DEFAULT_SERVER_URL
        if is_valid_url(user_input):
            return user_input

        print("Invalid URL, please ensure the server is reachable.")


def is_valid_url(url):
    """
    Checks if the provided URL is valid by making a GET request.

    :param url: URL to validate
    :return: True if URL is valid, False otherwise
    """

    health_url = f"{url}/health"

    try:
        response = requests.get(health_url, timeout=30)
        return response.status_code == 200
    except requests.RequestException:
        return False


def create_config(user_id, server_url):
    """
    Creates configuration file with user ID and server URL.

    :param user_id: User ID to store in config
    :param server_url: Server URL to store in config
    """
    print("Creating configuration file...")

    config = configparser.ConfigParser()
    config["User"] = {"user_id": user_id}
    config["Server"] = {"server_url": server_url}

    with open(
        os.path.join(MISTER_PATH, "cloud_saves.ini"), "w", encoding="utf-8"
    ) as configfile:
        config.write(configfile)


def is_config_existing():
    """
    Checks if configuration file exists.

    :return: True if config file exists, False otherwise
    """

    return os.path.isfile(os.path.join(MISTER_PATH, "cloud_saves.ini"))


def read_config():
    """
    Reads configuration file.

    :return: ConfigParser object with loaded config
    """

    config = configparser.ConfigParser()
    config.read(os.path.join(MISTER_PATH, "cloud_saves.ini"))
    return config


def is_client_installed():
    """
    Checks if the Mister Cloud Saves Client is installed.

    :return: True if client is installed, False otherwise
    """

    client_bin = os.path.join(CLIENT_DIR, "mister_save_client")
    ini_file = os.path.join(MISTER_PATH, "cloud_saves.ini")

    return os.path.isfile(client_bin) and os.path.isfile(ini_file)


def get_tag_and_latest_release_url():
    """
    Gets the latest release download URL from GitHub.

    :return: Download URL string
    """

    response = requests.get(GH_REPO_API_URL, timeout=30)
    if response.status_code == 200:
        data = response.json()
        tag_name = data.get("tag_name", "unknown")

        for asset in data.get("assets", []):
            if asset.get("name") == "client.tar.xz":
                return (asset.get("browser_download_url"), tag_name)

    print("Error fetching latest release info")
    sys.exit(1)


def fetch_launcher_script():
    """
    Downloads the Mister Cloud Saves Launcher Script.
    """
    print("Downloading Mister Cloud Saves Launcher Script...")

    response = requests.get(LAUNCHER_SCRIPT_URL, timeout=30)
    if response.status_code == 200:
        with open(
            os.path.join(CLIENT_DIR, "cloud_saves_launcher.sh"),
            "wb",
        ) as file:
            file.write(response.content)
    else:
        print("Error downloading launcher script")
        sys.exit(1)


def fetch_client(download_url=None):
    """
    Downloads the Mister Cloud Saves Client.
    """
    print("Downloading Mister Cloud Saves Client...")

    if download_url is None:
        download_url, _ = get_tag_and_latest_release_url()

    response = requests.get(download_url, timeout=30)
    if response.status_code == 200:
        with open(
            os.path.join("/tmp", "client.tar.xz"),
            "wb",
        ) as file:
            file.write(response.content)
    else:
        print("Error downloading client")
        sys.exit(1)


def get_client_version():
    """
    Gets the installed Mister Cloud Saves Client version.

    :return: Version string
    """

    client_bin = os.path.join(CLIENT_DIR, "mister_save_client")

    if not os.path.isfile(client_bin):
        return "not installed"

    result = subprocess.run(
        [client_bin, "--version"],
        capture_output=True,
        text=True,
        check=True,
    )

    version = result.stdout.strip().split()[-1]

    return version


def extract_client():
    """
    Extracts the client archive to the client directory.
    """
    print("Extracting Mister Cloud Saves Client...")

    temp_archive_path = os.path.join("/tmp", "client.tar.xz")

    if os.path.isfile(temp_archive_path):
        if not os.path.isdir(CLIENT_DIR):
            os.makedirs(CLIENT_DIR)

        shutil.unpack_archive(temp_archive_path, CLIENT_DIR, format="xztar")

    else:
        print("Client archive not found")
        sys.exit(1)


def run_initial_sync():
    """
    Runs an initial one-shot sync of the Mister Cloud Saves Client.
    """
    print("Running initial sync...")

    client_bin = os.path.join(CLIENT_DIR, "mister_save_client")

    if not os.path.isfile(client_bin):
        print("Client binary not found")
        sys.exit(1)

    subprocess.run([client_bin, "--one-shot"], check=True)


def reboot_system():
    """
    Reboots the system after a countdown.
    """

    for i in range(5, 0, -1):
        print(f"Rebooting in {i} seconds...", end="\r")
        time.sleep(1)

    print("Rebooting now!            ")

    subprocess.run(["reboot"], check=True)


def update_user_scripts_install():
    """
    Updates user-startup.sh to include Mister Cloud Saves Client on startup.

    """
    print("Updating user-startup.sh to include Mister Cloud Saves Client...")

    script_path = os.path.join(MISTER_LINUX_DIR, "user-startup.sh")

    if not os.path.isfile(script_path):
        shutil.copy(
            os.path.join(MISTER_LINUX_DIR, "_user-startup.sh"),
            script_path,
        )

    with open(script_path, "a", encoding="utf-8") as file:
        file.write(f"\n{CLIENT_DIR}/cloud_saves_launcher.sh\n")


def update_user_scripts_migrate():
    """
    Migrates user-startup.sh to ensure Mister Cloud Saves Client using the current command
    """
    print(
        "Migrating user-startup.sh to ensure Mister Cloud Saves Client uses the correct command..."
    )

    script_path = os.path.join(MISTER_LINUX_DIR, "user-startup.sh")

    legacy_command = f"{CLIENT_DIR}/mister_save_client &"
    current_command = f"{CLIENT_DIR}/cloud_saves_launcher.sh"

    if os.path.isfile(script_path):
        with open(script_path, "r", encoding="utf-8") as file:
            lines = file.readlines()

        with open(script_path, "w", encoding="utf-8") as file:
            for line in lines:
                if legacy_command in line:
                    file.write(line.replace(legacy_command, current_command))
                else:
                    file.write(line)


def update_user_scripts_remove():
    """
    Updates user-startup.sh to remove Mister Cloud Saves Client on startup.
    """
    print("Updating user-startup.sh to remove Mister Cloud Saves Client...")

    script_path = os.path.join(MISTER_LINUX_DIR, "user-startup.sh")

    if os.path.isfile(script_path):
        with open(script_path, "r", encoding="utf-8") as file:
            lines = file.readlines()

        with open(script_path, "w", encoding="utf-8") as file:
            for line in lines:
                if CLIENT_DIR not in line:
                    file.write(line)


def get_downloader_ini():
    """
    Reads the downloader.ini file

    :return: ConfigParser object with loaded downloader config
    """

    config = configparser.ConfigParser()
    config.read(os.path.join(MISTER_PATH, "downloader.ini"))
    return config


def add_to_updater_if_needed():
    """
    Adds Mister Cloud Saves database update to downloader.ini if not already present.
    """

    config = get_downloader_ini()

    if "mister_cloud_saves" not in config.sections():
        print("Adding Mister Cloud Saves database update to downloader.ini...")

        config["mister_cloud_saves"] = {}
        config["mister_cloud_saves"]["db_url"] = UPDATE_DB_RAW_URL

        with open(
            os.path.join(MISTER_PATH, "downloader.ini"),
            "w",
            encoding="utf-8",
        ) as configfile:
            config.write(configfile)


def remove_from_updater():
    """
    Removes Mister Cloud Saves database update from downloader.ini if present.
    """

    config = get_downloader_ini()

    if "mister_cloud_saves" in config.sections():
        print("Removing Mister Cloud Saves database update from downloader.ini...")

        config.remove_section("mister_cloud_saves")

        with open(
            os.path.join(MISTER_PATH, "downloader.ini"),
            "w",
            encoding="utf-8",
        ) as configfile:
            config.write(configfile)


def create_updates_dir_if_needed():
    """
    Creates the updates directory if it does not exist.
    """

    updates_dir = os.path.join(CLIENT_DIR, "updates")
    if not os.path.isdir(updates_dir):
        os.makedirs(updates_dir)


def save_client_pid():
    """
    Retrieves the PID of the running Mister Cloud Saves Client.

    :return: PID as integer
    """

    pid_path = os.path.join("/var/run", "mister_save_client.pid")

    if not os.path.isfile(pid_path):
        return 0

    with open(pid_path, "r", encoding="utf-8") as pid_file:
        pid = pid_file.read().strip()
    return int(pid)


def stop_client_process():
    """
    Stops the running Mister Cloud Saves Client process.
    """

    pid = save_client_pid()
    if pid == 0:
        print("Mister Cloud Saves Client is not running.")
        return
    print(f"Stopping Mister Cloud Saves Client with PID {pid}...")

    try:
        os.kill(pid, signal.SIGTERM)
    except ProcessLookupError:
        pass


def change_server():
    """
    Changes the server URL in the configuration file.
    """

    stop_client_process()

    if is_config_existing():
        config_path = os.path.join(MISTER_PATH, "cloud_saves.ini")
        os.remove(config_path)

    server_url = get_server_url()
    user_id = get_user_id(server_url)
    create_config(user_id, server_url)

    run_initial_sync()
    reboot_system()


def install():
    """
    The installer function for Mister Cloud Saves Client.
    """
    print("Installing Mister Cloud Saves Client...")

    stop_client_process()
    fetch_launcher_script()
    fetch_client()
    extract_client()

    if not is_config_existing():
        server_url = get_server_url()
        user_id = get_user_id(server_url)
        create_config(user_id, server_url)
    else:
        print("Configuration file already exists. Skipping creation.")

    update_user_scripts_install()
    create_updates_dir_if_needed()
    add_to_updater_if_needed()

    run_initial_sync()
    reboot_system()


def uninstall():
    """
    Uninstalls the Mister Cloud Saves Client.
    """
    print("Uninstalling Mister Cloud Saves Client...")

    update_user_scripts_remove()
    remove_from_updater()
    stop_client_process()

    if os.path.isdir(CLIENT_DIR):
        shutil.rmtree(CLIENT_DIR)

    config_path = os.path.join(MISTER_PATH, "cloud_saves.ini")
    if os.path.isfile(config_path):
        os.remove(config_path)

    print("Mister Cloud Saves Client uninstalled.")

    reboot_system()


def update_self():
    """
    Updates the Mister Cloud Saves installer script (this one).
    """
    print("Checking for installer script updates...")

    tmp_dir = os.path.abspath("/media/fat/cloud_saves/tmp/")
    tmp_path = os.path.join(tmp_dir, "cloud_saves.sh")
    if not os.path.isdir(tmp_dir):
        os.makedirs(tmp_dir)

    response = requests.get(SCRIPT_RAW_URL, timeout=30)
    installer_path = os.path.join("/media/fat/Scripts", "cloud_saves.sh")

    if response.status_code == 200:
        tmp_hash = hashlib.sha256(response.content).hexdigest()

        with open(installer_path, "rb") as current_file:
            current_hash = hashlib.sha256(current_file.read()).hexdigest()

        if tmp_hash == current_hash:
            print("Script is already up to date.")
            return

        print("Updating script...")
        with open(
            tmp_path,
            "wb",
        ) as file:
            file.write(response.content)

        shutil.move(
            tmp_path,
            os.path.join("/media/fat/Scripts", "cloud_saves.sh"),
        )

        print("Installer script updated successfully.")
        print("Restarting installer...")

        os.execv(installer_path, [installer_path, "--update-client-only"])

    else:
        print("Error updating script")
        sys.exit(1)


def update():
    """
    Updates the Mister Cloud Saves Client.
    """

    print("Checking for Mister Cloud Saves Client updates...")

    current_version = get_client_version()
    client_download_url, latest_version = get_tag_and_latest_release_url()
    print(f"Current installed version: {current_version}")
    print(f"Latest available version: {latest_version}")

    # Ensure the updates directory exists and the updater is configured
    add_to_updater_if_needed()
    create_updates_dir_if_needed()
    update_user_scripts_migrate()

    fetch_launcher_script()

    if current_version == latest_version:
        print("Mister Cloud Saves Client is already up to date.")
        return

    print("Updating to the latest version...")

    stop_client_process()

    fetch_client(client_download_url)
    extract_client()

    run_initial_sync()

    reboot_system()


if __name__ == "__main__":
    ACTION = None

    if len(sys.argv) >= 2:
        ACTION = sys.argv[1]
    else:
        print("Mister Cloud Saves Script")
        print("=========================")

        if not is_client_installed():
            print("Client is not installed.")
            ACTION = "--install"
        else:
            while True:
                print("please choose an action:")
                print("1. Install")
                print("2. Update")
                print("3. Uninstall")
                print("4. Change Server")
                print("5. Exit")

                choice = input("Enter choice (1|2|3|4|5): ").strip()

                if choice == "1":
                    ACTION = "--install"
                elif choice == "2":
                    ACTION = "--update"
                elif choice == "3":
                    ACTION = "--uninstall"
                elif choice == "4":
                    ACTION = "--change-server"
                elif choice == "5":
                    print("Exiting.")
                    sys.exit(0)
                else:
                    print("Invalid choice. Please enter 1, 2, 3, 4, or 5.")
                    continue
                break

    if ACTION.lower() == "--install":
        install()
    elif ACTION.lower() == "--update":
        update_self()
        update()
    elif ACTION.lower() == "--update-client-only":
        update()
    elif ACTION.lower() == "--uninstall":
        uninstall()
    elif ACTION.lower() == "--change-server":
        change_server()
    else:
        print(
            "Invalid action. Use '--install', '--update', '--uninstall', or '--change-server'."
        )
        sys.exit(1)