#!/user/bin/env python

# Copyright (c) 2017 VisualDL Authors. All Rights Reserve.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# =======================================================================

import os
import time
import sys
import multiprocessing
import threading
import re
import webbrowser
import requests

from visualdl import __version__
from visualdl.utils import update_util

from flask import (Flask, Response, redirect, request, send_file, make_response)
from flask_babel import Babel

import visualdl.server
from visualdl.server.api import create_api_call
from visualdl.server.args import (ParseArgs, parse_args)
from visualdl.server.log import info
from visualdl.server.template import Template

SERVER_DIR = os.path.join(visualdl.ROOT, 'server')

support_language = ["en", "zh"]
default_language = support_language[0]

server_path = os.path.abspath(os.path.dirname(sys.argv[0]))
template_file_path = os.path.join(SERVER_DIR, "./dist")
mock_data_path = os.path.join(SERVER_DIR, "./mock_data/")

check_live_path = '/alive'


def create_app(args):
    # disable warning from flask
    cli = sys.modules['flask.cli']
    cli.show_server_banner = lambda *x: None

    app = Flask('visualdl', static_folder=None)
    app.logger.disabled = True

    # set static expires in a short time to reduce browser's memory usage.
    app.config['SEND_FILE_MAX_AGE_DEFAULT'] = 30

    app.config['BABEL_DEFAULT_LOCALE'] = default_language
    babel = Babel(app)
    api_call = create_api_call(args.logdir, args.model, args.cache_timeout)

    if args.telemetry:
        update_util.PbUpdater(args.product).start()

    public_path = args.public_path
    api_path = public_path + '/api'

    def append_query_string(url):
        query_string = ''
        if request.query_string:
            query_string = '?' + request.query_string.decode()
        return url + query_string

    @babel.localeselector
    def get_locale():
        lang = args.language
        if not lang or lang not in support_language:
            lang = request.accept_languages.best_match(support_language)
        return lang

    if not args.api_only:

        template = Template(
            os.path.join(server_path, template_file_path),
            PUBLIC_PATH=public_path.lstrip('/'),
            API_TOKEN_KEY='',
            TELEMETRY_ID='63a600296f8a71f576c4806376a9245b' if args.telemetry else ''
        )

        @app.route('/')
        def base():
            return redirect(append_query_string(public_path), code=302)

        @app.route('/favicon.ico')
        def favicon():
            icon = os.path.join(template_file_path, 'favicon.ico')
            if os.path.exists(icon):
                return send_file(icon)
            return 'file not found', 404

        @app.route(public_path + '/')
        def index():
            return redirect(append_query_string(public_path + '/index'), code=302)

        @app.route(public_path + '/<path:filename>')
        def serve_static(filename):
            is_not_page_request = re.search(r'\..+$', filename)
            response = template.render(filename if is_not_page_request else 'index.html')
            if not is_not_page_request:
                response.set_cookie('vdl_lng', get_locale(), path='/', samesite='Strict', secure=False, httponly=False)
            return response

    @app.route(api_path + '/<path:method>')
    def serve_api(method):
        data, mimetype, headers = api_call(method, request.args)
        return make_response(Response(data, mimetype=mimetype, headers=headers))

    @app.route(check_live_path)
    def check_live():
        return '', 204

    return app


def wait_until_live(args: ParseArgs):
    url = 'http://{host}:{port}'.format(host=args.host, port=args.port)
    while True:
        try:
            requests.get(url + check_live_path)
            info('Running VisualDL at http://%s:%s/ (Press CTRL+C to quit)', args.host, args.port)

            if args.host == 'localhost':
                info('Serving VisualDL on localhost; to expose to the network, use a proxy or pass --host 0.0.0.0')

            if args.api_only:
                info('Running in API mode, only %s/* will be served.', args.public_path + '/api')

            break
        except Exception:
            time.sleep(0.5)
    if not args.api_only and args.open_browser:
        webbrowser.open(url + args.public_path)


def _run(args):
    args = ParseArgs(**args)
    os.system('')
    info('\033[1;33mVisualDL %s\033[0m', __version__)
    app = create_app(args)
    threading.Thread(target=wait_until_live, args=(args,)).start()
    app.run(debug=False, host=args.host, port=args.port, threaded=False)


def run(logdir=None, **options):
    args = {
        'logdir': logdir
    }
    args.update(options)
    p = multiprocessing.Process(target=_run, args=(args,))
    p.start()
    return p.pid


def main():
    args = parse_args()
    _run(args)


if __name__ == '__main__':
    main()