package cmd

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"os/exec"
	"strings"

	"go.jolheiser.com/gpm/config"

	"github.com/AlecAivazis/survey/v2"
	"github.com/urfave/cli/v2"
	"go.jolheiser.com/beaver"
)

var Get = cli.Command{
	Name:  "get",
	Usage: "Get package(s)",
	Flags: []cli.Flag{
		&cli.BoolFlag{
			Name:  "ignore-local",
			Usage: "Ignore local packages",
		},
		&cli.BoolFlag{
			Name:  "offline",
			Usage: "Offline mode, return error instead of querying server",
		},
	},
	Action: doGet,
}

func doGet(ctx *cli.Context) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}

	pkgs := ctx.Args().Slice()
	if len(pkgs) == 0 {
		pkgsQuestion := &survey.Multiline{
			Message: "Enter packages to get, one for each line",
		}
		var pkgsAnswer string

		if err := survey.AskOne(pkgsQuestion, &pkgsAnswer); err != nil {
			return err
		}

		pkgs = strings.Split(pkgsAnswer, "\n")
	}

	local := cfg.Packages.Map()
	for _, pkg := range pkgs {
		var url string
		if u, ok := local[pkg]; ok && !ctx.Bool("ignore-local") {
			url = u.Import
		} else if !ctx.Bool("offline") {
			u, err := queryServer(ctx.String("url"), pkg)
			if err != nil {
				beaver.Error(err)
				continue
			}
			url = u
		}

		if url == "" {
			beaver.Errorf("no package found for `%s`", pkg)
			continue
		}

		beaver.Infof("getting `%s`...", pkg)
		if err := goGet(url); err != nil {
			beaver.Error(err)
		}
	}

	return nil
}

func queryServer(server, name string) (string, error) {
	endpoint := fmt.Sprintf("%s/package/%s", server, name)
	resp, err := http.Get(endpoint)
	if err != nil {
		return "", fmt.Errorf("could not query server at `%s`", endpoint)
	}

	if resp.StatusCode != http.StatusOK {
		return "", fmt.Errorf("could not find server package for `%s`", name)
	}

	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	var pkg config.Package
	if err := json.Unmarshal(body, &pkg); err != nil {
		return "", err
	}

	return pkg.Import, nil
}

func goGet(url string) error {
	cmd := exec.Command("go", "get", url)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	return cmd.Run()
}