package logging

import (
	"io"
	"log/slog"
	"os"
	"path/filepath"
)

// New creates the process logger. Callers provide the sink so tests and the
// command entry point do not need to share global logging state.
func New(w io.Writer) *slog.Logger {
	if w == nil {
		w = io.Discard
	}
	return slog.New(slog.NewJSONHandler(w, &slog.HandlerOptions{Level: slog.LevelInfo}))
}

// OpenFile creates an append-only local diagnostic log in the configured
// directory. It never falls back to cwd, so a bad configured directory stays
// visible to the caller instead of scattering logs beside a shortcut.
func OpenFile(directory string) (*slog.Logger, io.Closer, error) {
	if err := os.MkdirAll(directory, 0o700); err != nil {
		return nil, nil, err
	}
	file, err := os.OpenFile(filepath.Join(directory, "chub.log"), os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o600)
	if err != nil {
		return nil, nil, err
	}
	return New(file), file, nil
}