# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
#
# 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.
"""
Usage:
    Host a trained paddle model with one line command
    Example:
        python -m paddle_serving_server.serve --model ./serving_server_model --port 9292
"""
import argparse
import sys
import json
import base64
import time
from multiprocessing import Process
from .web_service import WebService, port_is_available
from flask import Flask, request
import sys
if sys.version_info.major == 2:
    from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
elif sys.version_info.major == 3:
    from http.server import BaseHTTPRequestHandler, HTTPServer


def parse_args():  # pylint: disable=doc-string-missing
    parser = argparse.ArgumentParser("serve")
    parser.add_argument(
        "--thread", type=int, default=10, help="Concurrency of server")
    parser.add_argument(
        "--model", type=str, default="", help="Model for serving")
    parser.add_argument(
        "--port", type=int, default=9292, help="Port the server")
    parser.add_argument(
        "--name", type=str, default="None", help="Web service name")
    parser.add_argument(
        "--workdir",
        type=str,
        default="workdir",
        help="Working dir of current service")
    parser.add_argument(
        "--device", type=str, default="cpu", help="Type of device")
    parser.add_argument(
        "--mem_optim_off",
        default=False,
        action="store_true",
        help="Memory optimize")
    parser.add_argument(
        "--ir_optim", default=False, action="store_true", help="Graph optimize")
    parser.add_argument(
        "--use_mkl", default=False, action="store_true", help="Use MKL")
    parser.add_argument(
        "--max_body_size",
        type=int,
        default=512 * 1024 * 1024,
        help="Limit sizes of messages")
    parser.add_argument(
        "--use_encryption_model",
        default=False,
        action="store_true",
        help="Use encryption model")
    parser.add_argument(
        "--use_multilang",
        default=False,
        action="store_true",
        help="Use Multi-language-service")
    parser.add_argument(
        "--product_name",
        type=str,
        default=None,
        help="product_name for authentication")
    parser.add_argument(
        "--container_id",
        type=str,
        default=None,
        help="container_id for authentication")
    return parser.parse_args()


def start_standard_model(serving_port):  # pylint: disable=doc-string-missing
    args = parse_args()
    thread_num = args.thread
    model = args.model
    port = serving_port
    workdir = args.workdir
    device = args.device
    mem_optim = args.mem_optim_off is False
    ir_optim = args.ir_optim
    max_body_size = args.max_body_size
    use_mkl = args.use_mkl
    use_encryption_model = args.use_encryption_model
    use_multilang = args.use_multilang

    if model == "":
        print("You must specify your serving model")
        exit(-1)

    import paddle_serving_server as serving
    op_maker = serving.OpMaker()
    read_op = op_maker.create('general_reader')
    general_infer_op = op_maker.create('general_infer')
    general_response_op = op_maker.create('general_response')

    op_seq_maker = serving.OpSeqMaker()
    op_seq_maker.add_op(read_op)
    op_seq_maker.add_op(general_infer_op)
    op_seq_maker.add_op(general_response_op)

    server = None
    if use_multilang:
        server = serving.MultiLangServer()
    else:
        server = serving.Server()
    server.set_op_sequence(op_seq_maker.get_op_sequence())
    server.set_num_threads(thread_num)
    server.set_memory_optimize(mem_optim)
    server.set_ir_optimize(ir_optim)
    server.use_mkl(use_mkl)
    server.set_max_body_size(max_body_size)
    server.set_port(port)
    server.use_encryption_model(use_encryption_model)
    if args.product_name != None:
        server.set_product_name(args.product_name)
    if args.container_id != None:
        server.set_container_id(args.container_id)

    server.load_model_config(model)
    server.prepare_server(workdir=workdir, port=port, device=device)
    server.run_server()


class MainService(BaseHTTPRequestHandler):
    def get_available_port(self):
        default_port = 12000
        for i in range(1000):
            if port_is_available(default_port + i):
                return default_port + i

    def start_serving(self):
        start_standard_model(serving_port)

    def get_key(self, post_data):
        if "key" not in post_data:
            return False
        else:
            key = base64.b64decode(post_data["key"])
            with open(args.model + "/key", "w") as f:
                f.write(key)
            return True

    def check_key(self, post_data):
        if "key" not in post_data:
            return False
        else:
            key = base64.b64decode(post_data["key"])
            with open(args.model + "/key", "r") as f:
                cur_key = f.read()
            return (key == cur_key)

    def start(self, post_data):
        post_data = json.loads(post_data)
        global p_flag
        if not p_flag:
            if args.use_encryption_model:
                print("waiting key for model")
                if not self.get_key(post_data):
                    print("not found key in request")
                    return False
            global serving_port
            global p
            serving_port = self.get_available_port()
            p = Process(target=self.start_serving)
            p.start()
            time.sleep(3)
            if p.is_alive():
                p_flag = True
            else:
                return False
        else:
            if p.is_alive():
                if not self.check_key(post_data):
                    return False
            else:
                return False
        return True

    def do_POST(self):
        content_length = int(self.headers['Content-Length'])
        post_data = self.rfile.read(content_length)
        if self.start(post_data):
            response = {"endpoint_list": [serving_port]}
        else:
            response = {"message": "start serving failed"}
        self.send_response(200)
        self.send_header('Content-type', 'application/json')
        self.end_headers()
        self.wfile.write(json.dumps(response))


if __name__ == "__main__":

    args = parse_args()
    if args.name == "None":
        if args.use_encryption_model:
            p_flag = False
            p = None
            serving_port = 0
            server = HTTPServer(('localhost', int(args.port)), MainService)
            print(
                'Starting encryption server, waiting for key from client, use <Ctrl-C> to stop'
            )
            server.serve_forever()
        else:
            start_standard_model(args.port)
    else:
        service = WebService(name=args.name)
        service.load_model_config(args.model)
        service.prepare_server(
            workdir=args.workdir, port=args.port, device=args.device)
        service.run_rpc_service()

        app_instance = Flask(__name__)

        @app_instance.before_first_request
        def init():
            service._launch_web_service()

        service_name = "/" + service.name + "/prediction"

        @app_instance.route(service_name, methods=["POST"])
        def run():
            return service.get_prediction(request)

        app_instance.run(host="0.0.0.0",
                         port=service.port,
                         threaded=False,
                         processes=4)