package cli

import (
	"errors"
	"flag"
	"fmt"
	"io"
	"os"

	"werkdock/internal/registry"
	"werkdock/internal/store"
)

// pullCmd is `docker pull`: fetch an image from a registry into the
// store, through package registry (crane). The verb is a thin frontend,
// as the API server's images/create is (RFC 0005).
func pullCmd(args []string) int {
	fs := flag.NewFlagSet("pull", flag.ContinueOnError)
	fs.SetOutput(io.Discard)
	platform := fs.String("platform", registry.DefaultPlatform(), "os/arch to pull from a multi-arch image")
	if err := fs.Parse(args); err != nil {
		return fail(err)
	}
	rest := fs.Args()
	if len(rest) == 0 {
		return fail(errors.New("pull needs an IMAGE (werkdock pull [REGISTRY/]REPOSITORY[:TAG])"))
	}
	if len(rest) > 1 {
		return fail(fmt.Errorf("unexpected argument %q", rest[1]))
	}
	st, err := store.Default()
	if err != nil {
		return fail(err)
	}
	loaded, err := registry.Pull(st, rest[0], *platform, os.Stderr)
	if err != nil {
		return fail(err)
	}
	for _, name := range loaded {
		fmt.Printf("Pulled image: %s\n", name)
	}
	return 0
}