// Copyright 2017 Vector Creations Ltd
//
// 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.

package main

import (
	"fmt"
	"net/http"
	_ "net/http/pprof"
	"os"
	"strconv"
	"strings"

	"github.com/matrix-org/dendrite/common"
	"github.com/matrix-org/dendrite/roomserver/input"
	"github.com/matrix-org/dendrite/roomserver/query"
	"github.com/matrix-org/dendrite/roomserver/storage"
	"github.com/prometheus/client_golang/prometheus"
	sarama "gopkg.in/Shopify/sarama.v1"
)

var (
	database             = os.Getenv("DATABASE")
	kafkaURIs            = strings.Split(os.Getenv("KAFKA_URIS"), ",")
	inputRoomEventTopic  = os.Getenv("TOPIC_INPUT_ROOM_EVENT")
	outputRoomEventTopic = os.Getenv("TOPIC_OUTPUT_ROOM_EVENT")
	bindAddr             = os.Getenv("BIND_ADDRESS")
	// Shuts the roomserver down after processing a given number of messages.
	// This is useful for running benchmarks for seeing how quickly the server
	// can process a given number of messages.
	stopProcessingAfter = os.Getenv("STOP_AFTER")
)

func main() {
	db, err := storage.Open(database)
	if err != nil {
		panic(err)
	}

	kafkaConsumer, err := sarama.NewConsumer(kafkaURIs, nil)
	if err != nil {
		panic(err)
	}

	kafkaProducer, err := sarama.NewSyncProducer(kafkaURIs, nil)
	if err != nil {
		panic(err)
	}

	consumer := input.Consumer{
		ContinualConsumer: common.ContinualConsumer{
			Topic:          inputRoomEventTopic,
			Consumer:       kafkaConsumer,
			PartitionStore: db,
		},
		DB:                   db,
		Producer:             kafkaProducer,
		OutputRoomEventTopic: outputRoomEventTopic,
	}

	if stopProcessingAfter != "" {
		count, err := strconv.ParseInt(stopProcessingAfter, 10, 64)
		if err != nil {
			panic(err)
		}
		consumer.StopProcessingAfter = &count
		consumer.ShutdownCallback = func(message string) {
			fmt.Println("Stopping roomserver", message)
			os.Exit(0)
		}
	}

	if err = consumer.Start(); err != nil {
		panic(err)
	}

	queryAPI := query.RoomserverQueryAPI{
		DB: db,
	}

	queryAPI.SetupHTTP(http.DefaultServeMux)

	http.DefaultServeMux.Handle("/metrics", prometheus.Handler())

	fmt.Println("Started roomserver")

	// TODO: Implement clean shutdown.
	if err := http.ListenAndServe(bindAddr, nil); err != nil {
		panic(err)
	}
}