package envvars

import (
	"os"
	"strings"
)

func Object[T any](key string, defaultValue T, converter func(string) (T, error)) T {
	if v, ok := os.LookupEnv(key); ok {
		if v2, err := converter(v); err == nil {
			return v2
		}
	}
	return defaultValue
}

func ObjectSlice[T any](key, sep string, defaultValue []T, converter func(string) (T, error)) []T {
	return Object(key, defaultValue, func(s string) ([]T, error) {
		if s == "" {
			return []T{}, nil
		}

		splits := strings.Split(s, sep)
		values := make([]T, 0, len(splits))
		for _, s := range splits {
			v, err := converter(s)
			if err != nil {
				return values, err
			}
			values = append(values, v)
		}
		return values, nil
	})
}