package bootstrap

import (
	"strings"
	"testing"
)

func quietly(string) {}

// A flag answers, and answers wrongly is refused naming what would have worked.
func TestAFlagAnswersAndAWrongOneIsRefused(t *testing.T) {
	filter := Choice{Name: "packet-filter", Options: []string{"nftables", "ufw"}}

	got, err := decide(filter, "ufw", nil, quietly)
	if err != nil || got != "ufw" {
		t.Fatalf("an explicit answer was not taken: %q, %v", got, err)
	}

	_, err = decide(filter, "iptables", nil, quietly)
	if err == nil {
		t.Fatal("an answer nothing offers was accepted")
	}
	if !strings.Contains(err.Error(), "nftables") || !strings.Contains(err.Error(), "ufw") {
		t.Fatalf("the refusal does not say what would have worked: %v", err)
	}
}

// A lone option answers itself — and says so, because "it chose for me" and "there was nothing to
// choose" read identically afterwards unless one of them speaks.
func TestALoneOptionAnswersItselfAloud(t *testing.T) {
	var said []string
	got, err := decide(Choice{Name: "private-network", Options: []string{"wireguard"}},
		"", nil, func(line string) { said = append(said, line) })
	if err != nil || got != "wireguard" {
		t.Fatalf("the only option was not taken: %q, %v", got, err)
	}
	if len(said) == 0 || !strings.Contains(said[0], "only option") {
		t.Fatalf("choosing silently: %v", said)
	}
}

// A terminal is asked; an empty answer takes the default when there is one.
func TestATerminalIsAskedAndEmptyTakesTheDefault(t *testing.T) {
	asked := 0
	prompt := func(c Choice) (string, error) { asked++; return "", nil }
	got, err := decide(Choice{Name: "extras", Default: "none"}, "", prompt, quietly)
	if err != nil || got != "none" || asked != 1 {
		t.Fatalf("empty answer at a prompt did not take the default: %q asked=%d %v", got, asked, err)
	}
}

// **Unattended and required is a refusal, not a guess.** The lab and any machine without a
// terminal must be answerable by flags — and a required choice with no flag has to stop the run
// naming the flag, because a guessed packet filter is a machine somebody else configured.
func TestUnattendedAndRequiredRefusesNamingTheFlag(t *testing.T) {
	_, err := decide(Choice{Name: "packet-filter", Options: []string{"nftables", "ufw"}},
		"", nil, quietly)
	if err == nil {
		t.Fatal("a required choice was guessed for an unattended run")
	}
	if !strings.Contains(err.Error(), "--packet-filter") {
		t.Fatalf("the refusal does not name the flag that answers it: %v", err)
	}
}