package main

import (
	"errors"
	"fmt"
	"runtime"
	"time"

	log "github.com/judwhite/logrjack"
)

type fields map[string]interface{} // optional, makes the call the AddFields look nice

func main() {
	start := time.Now()

	// Setup the log file name, log rolling options
	log.Setup(log.Settings{
		Filename:    "example.log", // optional, defaults to ./logs/<procname>.log
		MaxSizeMB:   100,
		MaxAgeDays:  30,
		WriteStdout: true,
	})

	// Simple log message
	log.Info("Welcome!")

	// AddFields example
	entry := log.NewEntry()
	entry.AddFields(fields{
		"runtime_version": runtime.Version(),
		"arch":            runtime.GOARCH,
	})
	entry.Info("OK")

	// error/panic examples
	errorExamples()

	// AddField example
	entry = log.NewEntry()
	entry.AddField("uptime", time.Since(start))
	entry.Info("Shutting down.")
}

func errorExamples() {
	// Error and panic examples. You might use this in an HTTP handler for
	// errors, or as part of the middleware for panics.

	// numerator, denominator
	n, d := 10, 0

	// 'divide' panics, recovers, adds the callstack, and returns an error
	entry := log.NewEntry()
	if res, err := divide(n, d, entry); err != nil {
		entry.Error(err)
	} else {
		entry.Infof("%d/%d=%d", n, d, res)
	}

	// 'safeDivide' checks if d == 0. if so it adds the callstack and returns an error
	entry = log.NewEntry()
	if res, err := safeDivide(n, d, entry); err != nil {
		entry.Error(err)
	} else {
		entry.Infof("%d/%d=%d", n, d, res)
	}
}

func divide(n, d int, entry log.Entry) (res int, err error) {
	defer func() {
		perr := recover()
		if perr != nil {
			entry.AddCallstack()
			var ok bool
			err, ok = perr.(error)
			if ok {
				return
			}
			err = errors.New(fmt.Sprintf("%v", perr))
		}
	}()

	res = n / d
	return
}

func safeDivide(n, d int, entry log.Entry) (int, error) {
	if d == 0 {
		entry.AddCallstack()
		return 0, errors.New("d must not equal 0")
	}
	return n / d, nil
}