package callstest

import (
	"fmt"
	"os"
	"runtime"
	"strings"
	"testing"
	"time"

	"amadan.net/oficina/calls/internal/calls/keymailtest"
)

// TestMain keeps Keymail classification inside the process: every POST
// /signin now classifies its address (auth.go's gateBegin), and without
// this each one would ask the real network whether example.com runs
// Keymail. Every DNS query is answered NXDOMAIN; no fixture is
// registered here, so every address is plain email.
func TestMain(m *testing.M) {
	restore, err := keymailtest.Install()
	if err != nil {
		fmt.Fprintln(os.Stderr, "keymailtest.Install:", err)
		os.Exit(1)
	}
	code := m.Run()
	// No test may leave a sign-in mail worker running: every app a test
	// builds has its queue closed in cleanup (Runtime.Close, a
	// TestHandle's stop, or buildForTest).
	if code == 0 {
		deadline := time.Now().Add(5 * time.Second)
		for mailWorkers() > 0 && time.Now().Before(deadline) {
			time.Sleep(10 * time.Millisecond)
		}
		if n := mailWorkers(); n > 0 {
			fmt.Fprintf(os.Stderr, "FAIL: %d sign-in mail queue goroutines still running after the tests\n", n)
			code = 1
		}
	}
	restore()
	os.Exit(code)
}

// mailWorkers counts goroutines running a sign-in mail queue's worker
// or log pump (internal/calls/signin_mail.go).
func mailWorkers() int {
	buf := make([]byte, 1<<22)
	stacks := string(buf[:runtime.Stack(buf, true)])
	return strings.Count(stacks, "(*mailQueue).run(") + strings.Count(stacks, "(*mailQueue).pump(")
}