package main

import (
	"flag"
	"fmt"
	"os"
	"slices"

	"src.opensuse.org/autogits/common"
)

func WriteNewMaintainershipFile(m *common.MaintainershipMap, filename string) {
	f, err := os.Create(filename + ".new")
	common.PanicOnError(err)
	common.PanicOnError(m.WriteMaintainershipFile(f))
	common.PanicOnError(f.Sync())
	common.PanicOnError(f.Close())
	common.PanicOnError(os.Rename(filename+".new", filename))
}

func run() error {
	pkg := flag.String("package", "", "Package to modify")
	rm := flag.Bool("rm", false, "Remove maintainer from package")
	add := flag.Bool("add", false, "Add maintainer to package")
	lint := flag.Bool("lint-only", false, "Reformat entire _maintainership.json only")
	flag.Parse()

	if (*add == *rm) && !*lint {
		return fmt.Errorf("Need to either add or remove a maintainer, or lint")
	}

	filename := common.MaintainershipFile
	if *lint {
		if len(flag.Args()) > 0 {
			filename = flag.Arg(0)
		}
	}

	data, err := os.ReadFile(filename)
	if os.IsNotExist(err) {
		return err
	}
	if err != nil {
		return err
	}

	m, err := common.ParseMaintainershipData(data)
	if err != nil {
		return fmt.Errorf("Failed to parse JSON: %w", err)
	}

	if *lint {
		m.Raw = nil // forces a rewrite
	} else {
		users := flag.Args()
		if len(users) > 0 {
			maintainers, ok := m.Data[*pkg]
			if !ok && !*add {
				return fmt.Errorf("No package %s and not adding one.", *pkg)
			}

			if *add {
				for _, u := range users {
					if !slices.Contains(maintainers, u) {
						maintainers = append(maintainers, u)
					}
				}
			}

			if *rm {
				newMaintainers := make([]string, 0, len(maintainers))
				for _, m := range maintainers {
					if !slices.Contains(users, m) {
						newMaintainers = append(newMaintainers, m)
					}
				}
				maintainers = newMaintainers
			}

			if len(maintainers) > 0 {
				slices.Sort(maintainers)
				m.Data[*pkg] = maintainers
			} else {
				delete(m.Data, *pkg)
			}
		}
	}

	WriteNewMaintainershipFile(m, filename)
	return nil
}

func main() {
	if err := run(); err != nil {
		common.LogError(err)
		os.Exit(1)
	}
}