package externalIpProvider

import (
	"errors"
	"net"
	"net/http"
	"net/url"
	externalIpProvider "realdnydns/pkg/externalIpProvider"
)

type ExternalIpProviderImplPlain struct {
	IPProviderURL string
	HTTPClient    *http.Client
}

type PlainExternalIpProviderConfig struct {
	Url string `yaml:"url"`
}

func New(config PlainExternalIpProviderConfig) (externalIpProvider.ExternalIpProvider, error) {
	if config.Url == "" {
		return nil, errors.New("url is required")
	}

	return &ExternalIpProviderImplPlain{
		config.Url,
		&http.Client{},
	}, nil
}

func (p *ExternalIpProviderImplPlain) GetExternalIp() (net.IP, error) {
	parsedUrl, err := url.Parse(p.IPProviderURL)
	if err != nil {
		return nil, err
	}

	res, err := p.HTTPClient.Get(parsedUrl.String())
	if err != nil {
		return nil, err
	}

	if res.StatusCode != 200 {
		return nil, errors.New("unexpected status code")
	}

	responseBody := make([]byte, res.ContentLength)
	res.Body.Read(responseBody)
	defer res.Body.Close()

	parsedIp := net.ParseIP(string(responseBody))
	if parsedIp == nil {
		return nil, errors.New("unable to parse ip")
	}

	return parsedIp, nil
}