package runtimelogs

import (
	"os"

	"evobgp/internal/store"
)

// Cleanup truncates or deletes a runtime log file synchronously.
func (s *Service) Cleanup(filename, mode string) (sizeBefore int64, sizeAfter *int64, err error) {
	if !s.Available() {
		return 0, nil, ErrUnavailable
	}
	if !store.ValidRuntimeLogCleanupAction(mode) {
		return 0, nil, ErrInvalidFilename
	}
	path, err := ResolveLogPath(s.cfg.RootDir, filename)
	if err != nil {
		return 0, nil, err
	}
	st, err := os.Stat(path)
	if err != nil {
		if os.IsNotExist(err) {
			return 0, nil, ErrNotFound
		}
		return 0, nil, err
	}
	if st.IsDir() {
		return 0, nil, ErrNotAFile
	}
	sizeBefore = st.Size()
	if sizeBefore > MaxCleanupBytes {
		return 0, nil, ErrFileTooLarge
	}

	switch mode {
	case store.RuntimeLogCleanupTruncate:
		if err := os.Truncate(path, 0); err != nil {
			return 0, nil, err
		}
		zero := int64(0)
		return sizeBefore, &zero, nil
	case store.RuntimeLogCleanupDelete:
		if err := os.Remove(path); err != nil {
			return 0, nil, err
		}
		return sizeBefore, nil, nil
	default:
		return 0, nil, ErrInvalidFilename
	}
}