import json
import pathlib
import hashlib
import requests
import base64
import sys
from os import geteuid
import subprocess


def compute_file_hash(filepath):
    with open(filepath, 'rb') as file_for_hash:
        data = file_for_hash.read()
    filesize = len(data)
    # Github sha value is computed as such:
    return hashlib.sha1(b"blob " + bytes(str(filesize), 'utf-8') + b"\0" + data).hexdigest()


def get_info(repo, filepath):
    url = f"https://api.github.com/repos/{repo}/contents/{filepath}"
    r = requests.get(url)
    sha = r.json()['sha']
    content = r.json()['content']
    return sha, content


def update():
    with open("config.json", "r") as jsonfile:
        config = json.load(jsonfile)

    print("Updating...")

    for repo in config['githubfilesync']:
        for reponame, value in repo.items():
            for filepath in value:
                localfile = pathlib.Path('files').joinpath(pathlib.Path(filepath).name)
                print(f"  * {localfile} ", end='')
                lastsha, content = get_info(reponame, filepath)

                if not localfile.exists():
                    content = base64.b64decode(content)
                    with open(localfile, 'wb') as f:
                        f.write(content)
                    print('-> Installed! ;)')

                else:
                    sha = compute_file_hash(localfile)

                    if sha == lastsha:
                        print('-> Up-to-date.')
                    else:
                        content = base64.b64decode(content)
                        with open(localfile, 'wb') as f:
                            f.write(content)
                        print('-> Updated!')


def print_menu(menu_options):
    for key in menu_options.keys():
        print(key, '->', menu_options[key])


def is_sudo():
    return True if geteuid() == 0 else False


def ask_port(default_port):
    while True:
        try:
            choice = input(f'What port would you like to listen on ? [{default_port}]: ')
            if choice == '':
                port = default_port
            else:
                port = int(choice)
            break
        except ValueError:
            print('Wrong input. Please enter a number ...')
    return port


def listen_http(files_dir):
    port = ask_port(80)
    ips = get_ips()

    print('The HTTP server is about to start.\nAvailable endpoints:')
    for iname in ips:
        if port == 80:
            print(f'  -> {iname}: http://{ips[iname]}/')
        else:
            print(f'  -> {iname}: http://{ips[iname]}:{port}/')

    if port < 1024 and not is_sudo():
        print('Listening on any port under 1024 requires root permissions.')
        cmd = ['sudo', 'python', '-m', 'http.server', '-d', files_dir, str(port)]
    else:
        cmd = ['python', '-m', 'http.server', '-d', files_dir, str(port)]
    subprocess.call(cmd)


def listen_smb(files_dir):
    port = ask_port(445)
    ips = get_ips()

    print('The HTTP server is about to start.\nAvailable endpoints:')
    for iname in ips:
        if port == 445:
            print(f'  -> {iname}: \\\\{ips[iname]}\\share\\')
        else:
            print(f'  -> {iname}: \\\\{ips[iname]}:{port}\\share\\  # This syntax (:port) is not supported on Windows ?')

    if port < 1024 and not is_sudo():
        print('Listening on any port under 1024 requires root permissions.')
        cmd = ['sudo', 'smbserver.py', '-port', str(port), 'share', files_dir]
    else:
        cmd = ['smbserver.py', '-port', str(port), 'share', files_dir]
    subprocess.call(cmd)


def get_public_ip():
    return requests.get('https://api.ipify.org').text


def get_ips():
    ips = dict()
    try:
        ips['public'] = get_public_ip()
    except requests.exceptions.ConnectionError:
        pass

    cmd = ['ip', 'a']
    out = subprocess.run(cmd, capture_output=True).stdout.decode('utf-8')
    lines = out.split('\n')

    while("" in lines):
        lines.remove("")

    for line in lines:
        if line[0].isdigit():
            iname = line.split(' ')[1].split(':')[0]
        if 'inet ' in line:
            ip = line.split(' ')[5].split('/')[0]
            if ip != '127.0.0.1':
                ips[iname] = ip
    return ips


def menu_choice(menu_options):
    while(True):
        print_menu(menu_options)
        option = ''
        try:
            option = int(input('Enter your choice: '))
        except ValueError:
            print('Wrong input. Please enter a number ...')

        files_dir = pathlib.Path.cwd().joinpath('files')

        if option == 1:
            listen_http(files_dir)
        elif option == 2:
            listen_smb(files_dir)
        elif option == 0:
            sys.exit('Quitting')
        else:
            print('Invalid option. Please enter a valid number.')


if __name__ == '__main__':
    menu_options = {
        1: 'HTTP',
        2: 'SMB',
        0: 'Exit',
    }
    update()
    menu_choice(menu_options)