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


def get_last_release_info(repo, credz):
    url = f"https://api.github.com/repos/{repo}/releases"
    r = requests.get(url, auth=credz)
    for release in r.json():
        if not release['draft'] and not release['prerelease']:
            return release['tag_name']


def githubmastersync(reponame, filepaths, credz):
    for filepath in filepaths:
        localfile = pathlib.Path('files').joinpath(pathlib.Path(filepath).name)
        print(f"  * {localfile} ", end='')
        lastsha, content = get_master_info(reponame, filepath, credz)

        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 githubreleasesync(reponame, repoinfo, credz):
    local_version = repoinfo['local_version']
    last_version = get_last_release_info(reponame, credz)

    filenames = repoinfo['files']

    for filename in filenames:
        localfile = pathlib.Path('files').joinpath(pathlib.Path(filename).name)
        urldl = f'https://github.com/{reponame}/releases/download/{last_version}/{filename}'
        print(f"  * {localfile} ", end='')

        if not localfile.exists():
            content = requests.get(urldl, auth=credz).content
            with open(localfile, 'wb') as f:
                f.write(content)

            print('-> Installed! ;)')
        else:
            if local_version == last_version:
                print('-> Up-to-date.')

            else:
                content = requests.get(urldl, auth=credz).content
                with open(localfile, 'wb') as f:
                    f.write(content)

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

                data['githubreleasesync'][reponame]['local_version'] = last_version

                with open("config.json", "w") as jsonfile:
                    json.dump(data, jsonfile, indent=4)

                print('-> Updated!')


def update(config):
    print("Updating...")
    with open("credz.json", "r") as jsonfile:
        credz = json.load(jsonfile)
    credz = (credz['username'], credz['token'])

    for reponame, filepaths in config['githubmastersync'].items():
        githubmastersync(reponame, filepaths, credz)

    for reponame, repoinfo in config['githubreleasesync'].items():
        githubreleasesync(reponame, repoinfo, credz)


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__':
    with open("config.json", "r") as jsonfile:
        config = json.load(jsonfile)

    update(config)

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