/*
rqlite -- a replicated SQLite database.

rqlite is a distributed system that provides a replicated SQLite database.
rqlite is written in Go and uses Raft to achieve consensus across all the
instances of the SQLite databases. rqlite ensures that every change made to
the database is made to a majority of underlying SQLite files, or none-at-all.
*/

package main

import (
	"bytes"
	"encoding/json"
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"os/signal"
	"runtime"
	"runtime/pprof"
	"time"

	sql "github.com/otoolep/rqlite/db"
	httpd "github.com/otoolep/rqlite/http"
	"github.com/otoolep/rqlite/store"
)

const sqliteDSN = "db.sqlite"

var httpAddr string
var raftAddr string
var joinAddr string
var dsn string
var cpuprofile string
var disableReporting bool

func init() {
	flag.StringVar(&raftAddr, "raft", "localhost:4001", "Raft communication bind address")
	flag.StringVar(&httpAddr, "http", "localhost:4002", "HTTP query server bind address")
	flag.StringVar(&joinAddr, "join", "", "host:port of leader to join")
	flag.StringVar(&dsn, "dsn", "", "SQLite DSN parameters")
	flag.StringVar(&cpuprofile, "cpuprofile", "", "Write CPU profile to file")
	flag.BoolVar(&disableReporting, "noreport", false, "Disable anonymised launch reporting")
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage: %s [arguments] <data-path>\n", os.Args[0])
		flag.PrintDefaults()
	}
}

func main() {
	flag.Parse()

	// Ensure the data path was set.
	if flag.NArg() == 0 {
		flag.Usage()
		os.Exit(1)
	}

	dataPath := flag.Arg(0)

	// Set up profiling, if requested.
	if cpuprofile != "" {
		log.Println("profiling enabled")
		f, err := os.Create(cpuprofile)
		if err != nil {
			log.Printf("unable to create path: %s", err.Error())
		}
		defer f.Close()

		err = pprof.StartCPUProfile(f)
		if err != nil {
			log.Printf("unable to start CPU Profile: %s", err.Error())
		}

		defer pprof.StopCPUProfile()
	}

	// Create and open the store.
	dbConf := sql.NewConfig()    // XXX CONSIDER SUPPORTING IN-MEMORY DATABASE! That way is fast, but log is persistence.
	dbConf.DSN = dsn
	store := store.New(dbConf, dataPath, raftAddr)
	if err := store.Open(joinAddr == ""); err != nil {
		log.Fatalf("failed to open store: %s", err.Error())
	}

	// If join was specified, make the join request.
	if joinAddr != "" {
		if err := join(joinAddr, raftAddr); err != nil {
			log.Fatalf("failed to join node at %s: %s", joinAddr, err.Error())
		}
	}

	// Create the HTTP query server.
	s := httpd.New(httpAddr, store)
	if err := s.Start(); err != nil {
		log.Fatalf("failed to start HTTP server: %s", err.Error())

	}

	if !disableReporting {
		reportLaunch()
	}

	terminate := make(chan os.Signal, 1)
	signal.Notify(terminate, os.Interrupt)
	<-terminate
	if err := store.Close(); err != nil {
		log.Printf("failed to close store: %s", err.Error())
	}
	log.Println("rqlite server stopped")
}

func join(joinAddr, raftAddr string) error {
	b, err := json.Marshal(map[string]string{"addr": raftAddr})
	if err != nil {
		return err
	}
	resp, err := http.Post(fmt.Sprintf("http://%s/join", joinAddr), "application-type/json", bytes.NewReader(b))
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	return nil
}

func reportLaunch() {
	json := fmt.Sprintf(`{"os": "%s", "arch": "%s", "app": "rqlite", "raft": "hashicorp"}`, runtime.GOOS, runtime.GOARCH)
	data := bytes.NewBufferString(json)
	client := http.Client{Timeout: time.Duration(5 * time.Second)}
	go func() {
		_, err := client.Post("https://logs-01.loggly.com/inputs/8a0edd84-92ba-46e4-ada8-c529d0f105af/tag/reporting/",
			"application/json", data)
		if err != nil {
			log.Printf("report launch failed: %s", err.Error())
		}
	}()
}