import argparse
import base64
import io
import json
import os
import pickle
import urllib.parse as urlparse
import uuid
from functools import wraps

import waitress
from flask import jsonify, make_response, request, redirect, render_template, send_file, session
from requests import exceptions

from app import app
from app.models.config import Config
from app.request import Request
from app.utils.misc import valid_user_session
from app.utils.routing_utils import *


def auth_required(f):
    @wraps(f)
    def decorated(*args, **kwargs):
        auth = request.authorization

        # Skip if username/password not set
        whoogle_user = os.getenv('WHOOGLE_USER', '')
        whoogle_pass = os.getenv('WHOOGLE_PASS', '')
        if (not whoogle_user or not whoogle_pass) or \
                (auth and whoogle_user == auth.username and whoogle_pass == auth.password):
            return f(*args, **kwargs)
        else:
            return make_response('Not logged in', 401, {'WWW-Authenticate': 'Basic realm="Login Required"'})
    return decorated


@app.before_request
def before_request_func():
    g.request_params = request.args if request.method == 'GET' else request.form
    g.cookies_disabled = False

    # Generate session values for user if unavailable
    if not valid_user_session(session):
        session['config'] = json.load(open(app.config['DEFAULT_CONFIG'])) \
            if os.path.exists(app.config['DEFAULT_CONFIG']) else {'url': request.url_root}
        session['uuid'] = str(uuid.uuid4())
        session['fernet_keys'] = generate_user_keys(True)

        # Flag cookies as possibly disabled in order to prevent against
        # unnecessary session directory expansion
        g.cookies_disabled = True

    if session['uuid'] not in app.user_elements:
        app.user_elements.update({session['uuid']: 0})

    # Always redirect to https if HTTPS_ONLY is set (otherwise default to False)
    https_only = os.getenv('HTTPS_ONLY', False)

    if https_only and request.url.startswith('http://'):
        return redirect(request.url.replace('http://', 'https://', 1), code=308)

    g.user_config = Config(**session['config'])

    if not g.user_config.url:
        g.user_config.url = request.url_root.replace('http://', 'https://') if https_only else request.url_root

    g.user_request = Request(request.headers.get('User-Agent'), language=g.user_config.lang)
    g.app_location = g.user_config.url


@app.after_request
def after_request_func(response):
    if app.user_elements[session['uuid']] <= 0 and '/element' in request.url:
        # Regenerate element key if all elements have been served to user
        session['fernet_keys']['element_key'] = '' if not g.cookies_disabled else app.default_key_set['element_key']
        app.user_elements[session['uuid']] = 0

    # Check if address consistently has cookies blocked, in which case start removing session
    # files after creation.
    # Note: This is primarily done to prevent overpopulation of session directories, since browsers that
    # block cookies will still trigger Flask's session creation routine with every request.
    if g.cookies_disabled and request.remote_addr not in app.no_cookie_ips:
        app.no_cookie_ips.append(request.remote_addr)
    elif g.cookies_disabled and request.remote_addr in app.no_cookie_ips:
        session_list = list(session.keys())
        for key in session_list:
            session.pop(key)

    return response


@app.errorhandler(404)
def unknown_page(e):
    return redirect(g.app_location)


@app.route('/', methods=['GET'])
@auth_required
def index():
    # Reset keys
    session['fernet_keys'] = generate_user_keys(g.cookies_disabled)

    return render_template('index.html',
                           languages=Config.LANGUAGES,
                           countries=Config.COUNTRIES,
                           config=g.user_config,
                           version_number=app.config['VERSION_NUMBER'])


@app.route('/opensearch.xml', methods=['GET'])
@auth_required
def opensearch():
    opensearch_url = g.app_location
    if opensearch_url.endswith('/'):
        opensearch_url = opensearch_url[:-1]

    template = render_template('opensearch.xml',
                               main_url=opensearch_url,
                               request_type='get' if g.user_config.get_only else 'post')
    response = make_response(template)
    response.headers['Content-Type'] = 'application/xml'
    return response


@app.route('/autocomplete', methods=['GET', 'POST'])
def autocomplete():
    q = g.request_params.get('q')

    if not q and not request.data:
        return jsonify({'?': []})
    elif request.data:
        q = urlparse.unquote_plus(request.data.decode('utf-8').replace('q=', ''))

    return jsonify([q, g.user_request.autocomplete(q)])


@app.route('/search', methods=['GET', 'POST'])
@auth_required
def search():
    # Reset element counter
    app.user_elements[session['uuid']] = 0

    search_util = RoutingUtils(request, g.user_config, session, cookies_disabled=g.cookies_disabled)
    query = search_util.new_search_query()

    # Redirect to home if invalid/blank search
    if not query:
        return redirect('/')

    # Generate response and number of external elements from the page
    response, elements = search_util.generate_response()
    if search_util.feeling_lucky:
        return redirect(response, code=303)

    # Keep count of external elements to fetch before element key can be regenerated
    app.user_elements[session['uuid']] = elements

    return render_template(
        'display.html',
        query=urlparse.unquote(query),
        search_type=search_util.search_type,
        dark_mode=g.user_config.dark,
        response=response,
        search_header=render_template(
            'header.html',
            dark_mode=g.user_config.dark,
            query=urlparse.unquote(query),
            search_type=search_util.search_type,
            mobile=g.user_request.mobile) if 'isch' not in search_util.search_type else '')


@app.route('/config', methods=['GET', 'POST', 'PUT'])
@auth_required
def config():
    if request.method == 'GET':
        return json.dumps(g.user_config.__dict__)
    elif request.method == 'PUT':
        if 'name' in request.args:
            config_pkl = os.path.join(app.config['CONFIG_PATH'], request.args.get('name'))
            session['config'] = pickle.load(open(config_pkl, 'rb')) if os.path.exists(config_pkl) else session['config']
            return json.dumps(session['config'])
        else:
            return json.dumps({})
    else:
        config_data = request.form.to_dict()
        if 'url' not in config_data or not config_data['url']:
            config_data['url'] = g.user_config.url

        # Save config by name to allow a user to easily load later
        if 'name' in request.args:
            pickle.dump(config_data, open(os.path.join(app.config['CONFIG_PATH'], request.args.get('name')), 'wb'))

        # Overwrite default config if user has cookies disabled
        if g.cookies_disabled:
            open(app.config['DEFAULT_CONFIG'], 'w').write(json.dumps(config_data, indent=4))

        session['config'] = config_data
        return redirect(config_data['url'])


@app.route('/url', methods=['GET'])
@auth_required
def url():
    if 'url' in request.args:
        return redirect(request.args.get('url'))

    q = request.args.get('q')
    if len(q) > 0 and 'http' in q:
        return redirect(q)
    else:
        return render_template('error.html', query=q)


@app.route('/imgres')
@auth_required
def imgres():
    return redirect(request.args.get('imgurl'))


@app.route('/element')
@auth_required
def element():
    cipher_suite = Fernet(session['fernet_keys']['element_key'])
    src_url = cipher_suite.decrypt(request.args.get('url').encode()).decode()
    src_type = request.args.get('type')

    try:
        file_data = g.user_request.send(base_url=src_url).content
        app.user_elements[session['uuid']] -= 1
        tmp_mem = io.BytesIO()
        tmp_mem.write(file_data)
        tmp_mem.seek(0)

        return send_file(tmp_mem, mimetype=src_type)
    except exceptions.RequestException:
        pass

    empty_gif = base64.b64decode('R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==')
    return send_file(io.BytesIO(empty_gif), mimetype='image/gif')


@app.route('/window')
@auth_required
def window():
    get_body = g.user_request.send(base_url=request.args.get('location')).text
    get_body = get_body.replace('src="/', 'src="' + request.args.get('location') + '"')
    get_body = get_body.replace('href="/', 'href="' + request.args.get('location') + '"')

    results = BeautifulSoup(get_body, 'html.parser')

    try:
        for script in results('script'):
            script.decompose()
    except Exception:
        pass

    return render_template('display.html', response=results)


def run_app():
    parser = argparse.ArgumentParser(description='Whoogle Search console runner')
    parser.add_argument('--port', default=5000, metavar='<port number>',
                        help='Specifies a port to run on (default 5000)')
    parser.add_argument('--host', default='127.0.0.1', metavar='<ip address>',
                        help='Specifies the host address to use (default 127.0.0.1)')
    parser.add_argument('--debug', default=False, action='store_true',
                        help='Activates debug mode for the server (default False)')
    parser.add_argument('--https-only', default=False, action='store_true',
                        help='Enforces HTTPS redirects for all requests')
    parser.add_argument('--userpass', default='', metavar='<username:password>',
                        help='Sets a username/password basic auth combo (default None)')
    args = parser.parse_args()

    if args.userpass:
        user_pass = args.userpass.split(':')
        os.environ['WHOOGLE_USER'] = user_pass[0]
        os.environ['WHOOGLE_PASS'] = user_pass[1]

    os.environ['HTTPS_ONLY'] = '1' if args.https_only else ''

    if args.debug:
        app.run(host=args.host, port=args.port, debug=args.debug)
    else:
        waitress.serve(app, listen="{}:{}".format(args.host, args.port))