package observability

import (
	"log/slog"
	"os"
)

// Configure installs the process-wide JSON logger used by every GL adapter.
func Configure(service string, level slog.Leveler) *slog.Logger {
	handler := slog.NewJSONHandler(os.Stderr, &slog.HandlerOptions{
		AddSource: true,
		Level:     level,
		ReplaceAttr: func(_ []string, attr slog.Attr) slog.Attr {
			switch attr.Key {
			case slog.TimeKey:
				attr.Key = "timestamp"
			case slog.LevelKey:
				attr.Key = "severity"
			case slog.MessageKey:
				attr.Key = "message"
			case slog.SourceKey:
				attr.Key = "source"
			}
			return attr
		},
	})
	logger := slog.New(handler).With("service", service)
	slog.SetDefault(logger)
	return logger
}