package main

import (
	"errors"
	"os"
	"regexp"
	"strings"

	"path/filepath"
)

func (a *App) fail(t *Task, err error) {
	if t.LocalPath != "" {
		_ = os.Remove(t.LocalPath + ".part")
	}
	if err == nil {
		err = errors.New("unknown download error")
	}
	t.Status, t.Error = "error", err.Error()
	a.db.Save(t)
	if refundErr := a.refundCredit(t); refundErr != nil {
		t.Error += "; credit refund failed: " + refundErr.Error()
		a.db.Save(t)
	}
}

var bad = regexp.MustCompile(`[/\\:*?"<>|]+`)

func safe(s string) string {
	s = strings.TrimSpace(s)
	s = bad.ReplaceAllString(s, "_")
	s = strings.Trim(s, ". ")
	if s == "" {
		return "Unknown"
	}
	return s
}

func audioPath(dir, artist, title, format string) string {
	return filepath.Join(dir, safe(artist)+" - "+safe(title)+"."+normalizedFormat(format))
}