#!/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 json
import os
import time
import sys
import signal
import multiprocessing
import threading
import re
import webbrowser
import requests
from visualdl.reader.reader import LogReader
from argparse import ArgumentParser

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

import visualdl.server
from visualdl.server import (lib, template)
from visualdl.server.log import logger
from visualdl.python.cache import MemCache

error_retry_times = 3
error_sleep_time = 2  # seconds

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]))
static_file_path = os.path.join(SERVER_DIR, "./static")
template_file_path = os.path.join(SERVER_DIR, "./dist")
mock_data_path = os.path.join(SERVER_DIR, "./mock_data/")


class ParseArgs(object):
    def __init__(self,
                 logdir,
                 host="0.0.0.0",
                 port=8040,
                 model_pb="",
                 cache_timeout=20,
                 language=None,
                 public_path=None):
        self.logdir = logdir
        self.host = host
        self.port = port
        self.model_pb = model_pb
        self.cache_timeout = cache_timeout
        self.language = language
        self.public_path = public_path


def try_call(function, *args, **kwargs):
    res = lib.retry(error_retry_times, function, error_sleep_time, *args,
                    **kwargs)
    if not res:
        logger.error("Internal server error. Retry later.")
    return res


def parse_args():
    """
    :return:
    """
    parser = ArgumentParser(
        description="VisualDL, a tool to visualize deep learning.")
    parser.add_argument(
        "-p",
        "--port",
        type=int,
        default=8040,
        action="store",
        dest="port",
        help="api service port")
    parser.add_argument(
        "-t",
        "--host",
        type=str,
        default="0.0.0.0",
        action="store",
        help="api service ip")
    parser.add_argument(
        "-m",
        "--model_pb",
        type=str,
        action="store",
        help="model proto in ONNX format or in Paddle framework format")
    parser.add_argument(
        "--logdir",
        required=True,
        action="store",
        dest="logdir",
        nargs="+",
        help="log file directory")
    parser.add_argument(
        "--cache_timeout",
        action="store",
        dest="cache_timeout",
        type=float,
        default=20,
        help="memory cache timeout duration in seconds, default 20", )
    parser.add_argument(
        "-L",
        "--language",
        type=str,
        action="store",
        help="set the default language")
    parser.add_argument(
        "-P",
        "--public-path",
        type=str,
        action="store",
        default="/app",
        help="set public path"
    )

    args = parser.parse_args()
    if not args.logdir:
        parser.print_help()
        sys.exit(-1)
    return args


# status, msg, data
def gen_result(status, msg, data):
    """
    :param status:
    :param msg:
    :return:
    """
    result = dict()
    result['status'] = status
    result['msg'] = msg
    result['data'] = data
    return result


def create_app(args):
    app = Flask(__name__, static_url_path="")
    # 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)
    log_reader = LogReader(args.logdir)

    # use a memory cache to reduce disk reading frequency.
    CACHE = MemCache(timeout=args.cache_timeout)
    cache_get = lib.cache_get(CACHE)

    public_path = args.public_path.rstrip('/')
    api_path = public_path + '/api'

    @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

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

    @app.route(public_path + "/")
    def index():
        lang = get_locale()
        if lang == default_language:
            return redirect(public_path + '/index', code=302)
        return redirect(public_path + '/' + lang + '/index', code=302)

    @app.route(public_path + '/<path:filename>')
    def serve_static(filename):
        return send_from_directory(
            os.path.join(server_path, static_file_path), filename
            if re.search(r'\..+$', filename) else filename + '.html')

    @app.route(api_path + "/components")
    def components():
        data = cache_get('/data/components', lib.get_components, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/runs')
    def runs():
        data = cache_get('/data/runs', lib.get_runs, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/tags')
    def tags():
        data = cache_get('/data/tags', lib.get_tags, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/logs')
    def logs():
        data = cache_get('/data/logs', lib.get_logs, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + "/scalars/tags")
    def scalar_tags():
        data = cache_get("/data/plugin/scalars/tags", try_call,
                         lib.get_scalar_tags, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + "/images/tags")
    def image_tags():
        data = cache_get("/data/plugin/images/tags", try_call,
                         lib.get_image_tags, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + "/audio/tags")
    def audio_tags():
        data = cache_get("/data/plugin/audio/tags", try_call,
                         lib.get_audio_tags, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + "/embeddings/tags")
    def embeddings_tags():
        data = cache_get("/data/plugin/embeddings/tags", try_call,
                         lib.get_embeddings_tags, log_reader)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/scalars/list')
    def scalars():
        run = request.args.get('run')
        tag = request.args.get('tag')
        key = os.path.join('/data/plugin/scalars/scalars', run, tag)
        data = cache_get(key, try_call, lib.get_scalar, log_reader, run, tag)
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/images/list')
    def images():
        mode = request.args.get('run')
        tag = request.args.get('tag')
        key = os.path.join('/data/plugin/images/images', mode, tag)

        data = cache_get(key, try_call, lib.get_image_tag_steps, log_reader,
                         mode, tag)
        result = gen_result(0, "", data)

        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/images/image')
    def individual_image():
        mode = request.args.get('run')
        tag = request.args.get('tag')  # include a index
        step_index = int(request.args.get('index'))  # index of step

        key = os.path.join('/data/plugin/images/individualImage', mode, tag,
                           str(step_index))
        data = cache_get(key, try_call, lib.get_individual_image, log_reader,
                         mode, tag, step_index)
        return Response(data, mimetype="image/png")

    @app.route(api_path + '/embeddings/embedding')
    def embeddings():
        run = request.args.get('run')
        tag = request.args.get('tag', 'default')
        dimension = request.args.get('dimension')
        reduction = request.args.get('reduction')
        key = os.path.join('/data/plugin/embeddings/embeddings', run,
                           dimension, reduction)
        data = cache_get(key, try_call, lib.get_embeddings, log_reader, run,
                         tag, reduction, int(dimension))
        result = gen_result(0, "", data)
        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/audio/list')
    def audio():
        run = request.args.get('run')
        tag = request.args.get('tag')
        key = os.path.join('/data/plugin/audio/audio', run, tag)

        data = cache_get(key, try_call, lib.get_audio_tag_steps, log_reader,
                         run, tag)
        result = gen_result(0, "", data)

        return Response(json.dumps(result), mimetype='application/json')

    @app.route(api_path + '/audio/audio')
    def individual_audio():
        run = request.args.get('run')
        tag = request.args.get('tag')  # include a index
        step_index = int(request.args.get('index'))  # index of step

        key = os.path.join('/data/plugin/audio/individualAudio', run, tag,
                           str(step_index))
        data = cache_get(key, try_call, lib.get_individual_audio, log_reader,
                         run, tag, step_index)
        response = send_file(
            data, as_attachment=True, attachment_filename='audio.wav')
        return response

    return app


def _open_browser(app, index_url):
    while True:
        # noinspection PyBroadException
        try:
            requests.get(index_url)
            break
        except Exception:
            time.sleep(0.5)
    webbrowser.open(index_url)


def _run(logdir,
         host="127.0.0.1",
         port=8080,
         model_pb="",
         cache_timeout=20,
         language=None,
         public_path="/app",
         open_browser=False):
    args = ParseArgs(
        logdir=logdir,
        host=host,
        port=port,
        model_pb=model_pb,
        cache_timeout=cache_timeout,
        language=language,
        public_path=public_path)
    logger.info(" port=" + str(args.port))
    app = create_app(args)
    index_url = "http://" + host + ":" + str(port) + args.public_path
    if open_browser:
        threading.Thread(
            target=_open_browser, kwargs={"app": app,
                                          "index_url": index_url}).start()
    app.run(debug=False, host=args.host, port=args.port, threaded=True)


def run(logdir,
        host="127.0.0.1",
        port=8040,
        model_pb="",
        cache_timeout=20,
        language=None,
        public_path="/app",
        open_browser=False):
    kwarg = {
        "logdir": logdir,
        "host": host,
        "port": port,
        "model_pb": model_pb,
        "cache_timeout": cache_timeout,
        "language": language,
        "public_path": public_path,
        "open_browser": open_browser
    }

    p = multiprocessing.Process(target=_run, kwargs=kwarg)
    p.start()
    return p.pid


def render_template(args):
    template.render(
        template_file_path,
        static_file_path,
        PUBLIC_PATH=args.public_path.strip('/'))


def clean_template(signalnum, frame):
    template.clean(static_file_path)
    sys.exit(0)


def main():
    args = parse_args()
    render_template(args)
    for sig in [signal.SIGINT, signal.SIGHUP, signal.SIGTERM]:
        signal.signal(sig, clean_template)
    logger.info(" port=" + str(args.port))
    app = create_app(args=args)
    app.run(debug=False, host=args.host, port=args.port, threaded=False)


if __name__ == "__main__":
    main()