package main

import (
	"context"
	"flag"
	"go/weather/internal"
	"go/weather/internal/version"
	"go/weather/internal/web"
	"go/weather/pkg/logger"
	"log"
	"os"
	"os/signal"
	"strings"
	"time"

	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

type flagParameter struct {
	configFile string
	logLevel   zapcore.Level
	logOutput  string
	wait       time.Duration
}

func main() {
	f := flagParameter{}
	var logLevel string
	flag.DurationVar(&f.wait, "graceful-timeout", time.Second*15, "the duration for which the server gracefully wait for existing connections to finish - e.g. 15s or 1m")
	flag.StringVar(&f.configFile, "filename", "config.hcl", "configuration filename")
	flag.StringVar(&logLevel, "logLevel", "info", "Log level")
	flag.StringVar(&f.logOutput, "logOutput", "logs/weather.log", "Output log path")
	flag.Parse()
	f.logLevel = parseLogLevel(logLevel)

	//logger
	loggerLevel := zap.NewAtomicLevelAt(f.logLevel)
	defaultLogger := logger.NewLogger("weather", f.logOutput, loggerLevel)
	defer defaultLogger.Sync()

	//configuration parsing
	config := internal.ParseConfiguration(defaultLogger.Sugar(), f.configFile)

	//http
	addr := web.NewListenAddr(config.Listen, config.Port)

	defaultLogger.Sugar().Infof("Weather server is listening on %s", addr)
	server := web.New(defaultLogger, addr, version.String()).
		WithTLSConfigure().
		WithHandler(config).
		WithHTTPLogging().
		WithErrorLogging()

	go func() {
		if err := server.Serve(); err != nil {
			defaultLogger.Sugar().Info(err)
		}
	}()

	c := make(chan os.Signal, 1)
	signal.Notify(c, os.Interrupt)

	<-c
	ctx, cancel := context.WithTimeout(context.Background(), f.wait)
	defer cancel()

	server.Shutdown(ctx)

	log.Println("shutting down")
	os.Exit(0)
}

func parseLogLevel(logLevel string) zapcore.Level {
	zapLevel := zap.InfoLevel
	switch strings.ToUpper(logLevel) {
	case "DEBUG":
		zapLevel = zapcore.DebugLevel
	case "INFO":
		zapLevel = zapcore.InfoLevel
	case "WARN":
		zapLevel = zapcore.WarnLevel
	case "ERROR":
		zapLevel = zapcore.ErrorLevel
	case "PANIC":
		zapLevel = zapcore.PanicLevel
	case "FATAL":
		zapLevel = zapcore.FatalLevel
	}
	return zapLevel
}