package utility

import (
	"bufio"
	"os"
	"regexp"
	"strings"
)

// Not all of these are going to be used, but just in case. This is more of a
// reference just for me. If more features are eventually added to this utility
// it may make sense to eventually use these.
var (
	regexPrettyName = regexp.MustCompile(`^PRETTY_NAME=(.*)$`)
	regexID         = regexp.MustCompile(`^ID=(.*)$`)
	regexVersionID  = regexp.MustCompile(`^VERSION_ID=(.*)$`)
	regexRockyName  = regexp.MustCompile(`^Rocky( Linux)? release`)
	regexOtherEL    = regexp.MustCompile(`^(CentOS|Fedora|Red Hat Enterprise|AlmaLinux|Scientific)( Linux)? release`)
	regexRedHatName = regexp.MustCompile(`^(Rocky|CentOS|Fedora|Red Hat Enterprise|AlmaLinux|Scientific)( Linux)? release`)

	VendorName       string
	SystemVersion    string
	SystemPrettyName string
	pasteBin         string
	osReleaseID      string
	simpleOSID       string
)

// Gets the distro id only
func GetDistroID() string {
	file, err := os.Open("/etc/os-release")
	if err != nil {
		return ""
	}
	defer file.Close()
	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		if m := regexID.FindStringSubmatch(scanner.Text()); m != nil {
			VendorName = strings.Trim(m[1], `"`)
		}
	}

	return VendorName
}

// Sets the pastebin based on the OS
func SetPasteOnOS() string {
	osReleaseID = GetDistroID()

	// The order should be: config -> this
	switch osReleaseID {
	case "rocky":
		pasteBin = "rpaste"
	case "redhat", "fedora", "centos", "almalinux", "scientific":
		pasteBin = "fpaste"
	case "opensuse-leap", "opensuse-tumbleweed", "sles":
		// this will be on rpaste for now
		pasteBin = "rpaste"
	default:
		pasteBin = "rpaste"
	}

	return pasteBin
}

// This is because there are several derivatives and some distros come from
// another. For example, rocky, rhel, alma, centos, fedora, they all generally
// operate the same (eg, sysinfo should work on all of them). But suse, this
// isn't that simple, unfortunately.
func GetGenericDistroID() string {
	osReleaseID = GetDistroID()

	switch osReleaseID {
	case "rocky", "redhat", "fedora", "centos", "almalinux", "scientific":
		simpleOSID = "redhat"
	case "opensuse-leap", "opensuse-tumbleweed", "sles":
		simpleOSID = "suse"
	case "debian", "ubuntu":
		simpleOSID = "debian"
	default:
		simpleOSID = "unknown"
	}

	return simpleOSID
}