package providers

import (
	"fmt"
	"os"
	"os/exec"
	"strconv"
	"strings"
)

func pathExists(path string) bool {
	_, err := os.Stat(path)
	return err == nil
}

func getPmPackages(packagerName string, packagerPath string) string {
	if pathExists(packagerPath) {
		pkgs, err := os.ReadDir(packagerPath)
		if err != nil {
			return "error reading " + packagerPath
		}
		if packagerName == "pacman" {
			return strconv.Itoa(len(pkgs)-1) + " (pacman)"
		}
		if packagerName == "apk" {
			out, err := exec.Command("apk", "info").Output()
			if err != nil {
				return "error reading apk package list"
			}
			pkgsRaw := strings.TrimSpace(string(out))

			pkgsList := strings.Split(pkgsRaw, "\n")
			pkgCount := len(pkgsList)

			if pkgsRaw == "" {
				pkgCount = 0
			}

			return fmt.Sprintf("%d (apk)", pkgCount)
		}
		return strconv.Itoa(len(pkgs)) + " (" + packagerName + ")"
	}
	return ""
}

func GetPkgs() string {
	rawPkgs := []string{
		getPmPackages("pacman", "/var/lib/pacman/local"),
		getPmPackages("apt", "/var/lib/apt"),
		getPmPackages("dnf", "/var/lib/dnf"),
		getPmPackages("flatpak", "/var/lib/flatpak"),
		getPmPackages("zypper", "/var/lib/zypp"),
		getPmPackages("xbps", "/var/db/xbps"),
		getPmPackages("emerge", "/var/lib/portage"),
		getPmPackages("nix-user", "~/.nix-profile/lib/nix/profiles/per-user"),
		getPmPackages("nix", "/nix/store"),
		getPmPackages("apk", "/etc/apk/"),
	}
	var pkgsList []string
	for _, p := range rawPkgs {
		if p != "" {
			pkgsList = append(pkgsList, p)
		}
	}
	if len(pkgsList) == 0 {
		return "unknown package manager"
	}

	return strings.Join(pkgsList[:], ", ")
}