package main

import (
	"os"
	"regexp"
	"strings"
	"testing"
)

func TestWaitPidArg(t *testing.T) {
	for _, tc := range []struct {
		name string
		args []string
		want int
	}{
		{"after the flag", []string{"--post-update", "--wait-pid", "4321"}, 4321},
		{"joined with =", []string{"--wait-pid=4321"}, 4321},
		{"absent", []string{"--post-update"}, 0},
		{"flag with nothing after it", []string{"--wait-pid"}, 0},
		{"not a number", []string{"--wait-pid", "later"}, 0},
	} {
		if got := waitPidArg(tc.args); got != tc.want {
			t.Errorf("%s: got %d, wanted %d", tc.name, got, tc.want)
		}
	}
}

// Every relaunch has to tell the new process which one to wait for.
//
// The auto-update relaunch lost that when its PowerShell helper was removed —
// the helper had waited for the pid, and nothing took over the job — and an
// operator was left with no window after an update and the previous OpsLog
// still running. This keeps the two spawn sites honest: if a relaunch is added
// without --wait-pid, it is the same bug again.
func TestEveryRelaunchPassesItsPid(t *testing.T) {
	spawn := regexp.MustCompile(`exec\.Command\(exe, "--(post-update|relaunch)"[^)]*\)`)
	for _, file := range []string{"update.go", "app.go"} {
		src, err := os.ReadFile(file)
		if err != nil {
			t.Fatalf("read %s: %v", file, err)
		}
		for _, call := range spawn.FindAllString(string(src), -1) {
			if !strings.Contains(call, "--wait-pid") {
				t.Errorf("%s: %s does not tell the new instance which process to wait for", file, call)
			}
		}
	}
}