package main

import (
	"database/sql"
	_ "embed"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/gorilla/mux"
	_ "github.com/mattn/go-sqlite3"
)

const (
	Addr         = "127.0.0.1:8000"
	ReadTimeout  = 15 * time.Second
	WriteTimeout = 15 * time.Second
	DatabasePath = "/var/lib/finserv/main.sqlite3"
)

//go:embed VERSION.txt
var versionTxt string
var router *mux.Router = mux.NewRouter()

func init() {
	log.SetFlags(0)
}

func main() {
	run(
		router,
		Addr,
		WriteTimeout,
		ReadTimeout,
		[]syscall.Signal{syscall.SIGTERM, syscall.SIGINT},
		DatabasePath,
	)
}

func run(
	handler http.Handler,
	addr string,
	wTimeout time.Duration,
	rTimeout time.Duration,
	signals []syscall.Signal,
	dbPath string,
) {
	log.Println("finserv finance server was started.")
	defer log.Println("finserv finance server was stopped.")

	var err error
	db, err := sql.Open("sqlite3", dbPath)
	if err != nil {
		log.Fatalf("Failed to open SQLite3 database '%s': %v", dbPath, err)
	}
	defer db.Close()

	_, err = db.Exec(`PRAGMA foreign_keys = ON;`)
	if err != nil {
		log.Fatalf("Failed to enable foreign key support in database: %v", err)
	}

	err = MigrateToLatest(db)
	if err != nil {
		log.Fatalf("Failed to migrate SQLite3 database '%s': %v", dbPath, err)
	}

	registerHandlers(router, db)

	server := &http.Server{
		Handler:      handler,
		Addr:         addr,
		WriteTimeout: wTimeout,
		ReadTimeout:  rTimeout,
	}

	go server.ListenAndServe()
	log.Printf("Serving at http://%s.\n", Addr)

	await(signals...)
}

func await(signals ...syscall.Signal) {
	listener := make(chan os.Signal, 1)
	for _, s := range signals {
		signal.Notify(listener, s)
	}
	sig := <-listener
	log.Printf("Received OS signal '%v'.\n", sig)
}