package main

import (
	"context"
	"io"
	"log"
	"os"
	"path/filepath"
	"sync"
	"testing"

	"github.com/stretchr/testify/require"
	waAdv "go.mau.fi/whatsmeow/proto/waAdv"
	"go.mau.fi/whatsmeow/store"
	"go.mau.fi/whatsmeow/store/sqlstore"
	"go.mau.fi/whatsmeow/types"
	waLog "go.mau.fi/whatsmeow/util/log"
)

// whatsappTestNumber is the phone number of the own account in the tests. It
// is a number for fiction.
const whatsappTestNumber = "15550001111"

// WhatsAppFake is a fake WhatsApp client. It keeps the event handler that the
// daemon gives it, and Emit gives events to the handler, as the library does.
type WhatsAppFake struct {
	mutex     sync.Mutex
	handle    func(event any) bool
	connected chan struct{}
}

// ConnectContext tells the test that the daemon connected.
func (f *WhatsAppFake) ConnectContext(ctx context.Context) error {
	close(f.connected)

	return nil
}

// Disconnect does nothing.
func (f *WhatsAppFake) Disconnect() {
}

// Emit gives event to the handler of the daemon and returns its answer.
func (f *WhatsAppFake) Emit(event any) bool {
	f.mutex.Lock()
	handle := f.handle
	f.mutex.Unlock()

	return handle(event)
}

// newClient keeps handle and returns the fake as the client of device.
func (f *WhatsAppFake) newClient(device *store.Device, handle func(event any) bool) WhatsAppClient {
	f.mutex.Lock()
	defer f.mutex.Unlock()

	f.handle = handle

	return f
}

// whatsappStartTest opens the WhatsApp of the data directory dir with a fake
// client and the test clock, and closes it at the end of the test.
func whatsappStartTest(t *testing.T, dir string) (*WhatsApp, *WhatsAppFake) {
	t.Helper()

	fake := &WhatsAppFake{
		connected: make(chan struct{}),
	}

	whatsapp, err := openWhatsApp(t.Context(), dir, newTestClock().Now, log.New(io.Discard, "", 0), fake.newClient)
	require.NoError(t, err)

	t.Cleanup(func() {
		require.NoError(t, whatsapp.Close())
	})

	return whatsapp, fake
}

// whatsappTestSession writes a session database with mode 0600 to the data
// directory dir. When linked is true, it holds a device linked to
// whatsappTestNumber, and else a device with no link.
func whatsappTestSession(t *testing.T, dir string, linked bool) {
	t.Helper()

	path := filepath.Join(dir, whatsappDirName, whatsappSessionFileName)
	require.NoError(t, os.MkdirAll(filepath.Dir(path), 0o700))
	require.NoError(t, os.WriteFile(path, nil, 0o600))

	address, err := whatsappSessionAddress(path)
	require.NoError(t, err)

	container, err := sqlstore.New(t.Context(), "sqlite", address, waLog.Noop)
	require.NoError(t, err)

	if linked {
		device := container.NewDevice()
		jid := types.NewADJID(whatsappTestNumber, 0, 1)
		device.ID = &jid
		device.Account = &waAdv.ADVSignedDeviceIdentity{
			Details:             []byte{},
			AccountSignature:    make([]byte, 64),
			AccountSignatureKey: make([]byte, 32),
			DeviceSignature:     make([]byte, 64),
		}
		require.NoError(t, device.Save(t.Context()))
	}

	require.NoError(t, container.Close())
}