package config

import (
	"fmt"
	"time"

	"gopkg.in/yaml.v3"
)

// Duration wraps time.Duration to support YAML unmarshalling from strings.
type Duration time.Duration

// UnmarshalYAML parses a duration string such as "5s" or "2m".
func (d *Duration) UnmarshalYAML(value *yaml.Node) error {
	if value.Kind != yaml.ScalarNode {
		return fmt.Errorf("duration must be a string, got %s", value.ShortTag())
	}
	parsed, err := time.ParseDuration(value.Value)
	if err != nil {
		return fmt.Errorf("parse duration %q: %w", value.Value, err)
	}
	*d = Duration(parsed)
	return nil
}

// MarshalYAML converts the duration to a string value.
func (d Duration) MarshalYAML() (any, error) {
	return time.Duration(d).String(), nil
}

// Duration returns the underlying time.Duration.
func (d Duration) Duration() time.Duration {
	return time.Duration(d)
}

// IsZero reports whether the duration has been set.
func (d Duration) IsZero() bool {
	return time.Duration(d) == 0
}

// SetDefault assigns the provided default if the duration is zero.
func (d *Duration) SetDefault(def time.Duration) {
	if d.IsZero() {
		*d = Duration(def)
	}
}