package lib

import (
	"encoding/json"
	"fmt"
	"net/http"
)

type PackageResponse struct {
	Name     string                    `json:"name"`
	Version  string                    `json:"version"`
	Versions map[string]PackageRelease `json:"versions"`
}

func GetPackageInfo(name string) (PackageResponse, error) {
	url := fmt.Sprintf("https://registry.npmjs.com/%s", name)
	var pr PackageResponse

	req, _ := http.NewRequest(http.MethodGet, url, nil)
	req.Header.Set("Accept", "application/json")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return pr, fmt.Errorf("could not get package info: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return pr, fmt.Errorf("Got a non 200 status code '%s': %v", resp.Status, resp.StatusCode)
	}

	if err := json.NewDecoder(resp.Body).Decode(&pr); err != nil {
		return pr, fmt.Errorf("could not decode json payload: %w", err)
	}
	return pr, nil
}

type PackageRelease struct {
	Name                 string            `json:"name"`
	VersionNumber        string            `json:"version"`
	ID                   string            `json:"_id"`
	Dependencies         map[string]string `json:"dependencies"`
	DevDependencies      map[string]string `json:"devDependencies"`
	OptionalDependencies map[string]string `json:"optionalDependencies"`
	Dist                 Distribution      `json:"dist"`
}

func (v PackageRelease) TarURL() string {
	return fmt.Sprintf("https://registry.npmjs.org/%s/-/%[1]s-%s.tgz", v.Name, v.VersionNumber)
}

type Distribution struct {
	Sum     string `json:"shasum"`
	Tarball string `json:"tarball"`
}