package dl

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

var dlURL = "https://golang.org/dl/?mode=json"

// Version is a Go version
type Version struct {
	Version string `json:"version"`
	Stable  bool   `json:"stable"`
	Files   []File `json:"files"`
}

// File is a dl file
type File struct {
	Filename string `json:"filename"`
	OS       string `json:"os"`
	Arch     string `json:"arch"`
	Version  string `json:"version"`
	Sha256   string `json:"sha256"`
	Size     int    `json:"size"`
	Kind     string `json:"kind"`
}

// Versions gets the latest Version(s) from dl
func Versions(ctx context.Context) ([]Version, error) {
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, dlURL, nil)
	if err != nil {
		return nil, err
	}
	req.Header.Set("User-Agent", "git.jojodev.com/golang/dl")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		return nil, err
	}
	defer res.Body.Close()

	var versions []Version
	if err := json.NewDecoder(res.Body).Decode(&versions); err != nil {
		return nil, err
	}

	return versions, nil
}