package wsconn

import (
	"context"
	"net"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"src.dualinventive.com/go/dinet/rpc"
	"src.dualinventive.com/go/websocketserver/internal/redis"
	wsclnt "src.dualinventive.com/go/websocketserver/internal/wsconn/testutil"
)

// wsconnMockServer wraps a httptest server for use as a MTIWss stub
type mockWsconnServer struct {
	url string
	srv *httptest.Server
}

// getFreeAddr gets a free TCP address from the kernel
func getFreeAddr(t *testing.T) string {
	l, err := net.Listen("tcp", ":0")
	require.NoError(t, err, "listen on port 0")
	defer l.Close()
	return l.Addr().String()
}

// New creates a stubbed mtiwss endpoint on URI with ep as endpoint path
func newWsconnMockServer(f http.HandlerFunc) *mockWsconnServer {
	t := &mockWsconnServer{}

	mux := http.NewServeMux()
	mux.HandleFunc("/", f)

	t.srv = httptest.NewServer(mux)
	t.url = strings.Replace(t.srv.URL+"/", "http", "ws", -1)

	return t
}

// Close graceful stops the mtiwss endpoint server
func (t *mockWsconnServer) Close() error {
	t.srv.Close()
	return nil
}

// URL returns the current MTIWss URL with endpoint
func (t *mockWsconnServer) URL() string {
	return t.url
}

// TestConnectDisconnect will try to connect and disconnect with a websocket client
func TestConnectDisconnect(t *testing.T) {
	// Start a HTTP server with a NewWsHandlerContext
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	addr := getFreeAddr(t)

	mux := http.NewServeMux()
	// NOTE: we don't pass a mtiwss requester as it is not used in this test
	//       no request are made when not sending from the client so this is safe
	mux.HandleFunc("/", NewWsHandlerContext(ctx, nil))

	srv := &http.Server{
		Addr:    addr,
		Handler: mux,
	}

	defer srv.Close()
	go srv.ListenAndServe()

	// Connect and disconnect with a websocket client
	clnt, err := wsclnt.NewClient("ws://" + addr)
	require.Nil(t, err)
	clnt.Close()
}

// TestPublishDeviceUpdate tests the public function for a single device update so all websocket clients
//  receive a filtered update in DI-Net RPC realtime:data format
func TestPublishDeviceUpdate(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// newMockServer
	srv := newWsconnMockServer(NewWsHandlerContext(ctx, nil))
	defer srv.Close()

	// Connect to the mockserver with a websocket client
	clnt, err := wsclnt.NewClient(srv.URL())
	require.Nil(t, err)
	defer clnt.Close()

	// Get the connect client from the list
	clients.mu.RLock()
	li := clients.list.Front()
	clients.mu.RUnlock()
	require.NotNil(t, li)
	require.NotNil(t, li.Value)
	c := li.Value.(*client)

	// Set device field subscriptions
	clients.mu.Lock()
	c.deviceFields = map[string][]string{
		"001fc23154ff65065182565553470187": {"device:info", "sensor:3:data"},
	}
	clients.mu.Unlock()

	// Publish mocked redis event
	ev := redis.Event{Chan: "device", Msg: "001fc23154ff65065182565553470187"}
	values := map[string]string{
		"device:info":   "{}",
		"sensor:3:data": "{}",
		"sensor:5:data": "{}", // Add a filtered field with value for testing filterFields
	}

	Publish(ev, values)

	// Read the RPC realtime:data message from the websocket
	msg, result, err := clnt.ReadRPCMsg()
	require.Nil(t, err)
	require.NotNil(t, msg)

	assert.Nil(t, msg.Error)
	assert.NotEqual(t, 0, msg.Time)
	assert.Equal(t, msg.Type, rpc.MsgTypePublish)
	assert.Equal(t, msg.ClassMethod, rpc.ClassMethodRealtimeData)
	assert.Equal(t, msg.DeviceUID, "001fc23154ff65065182565553470187")
	assert.JSONEq(t, result, `{"device:info":{},"sensor:3:data":{}}`)
}

// TestPublishProjectUpdate tests the public function for project updates so all websocket clients
//  receive a filtered update in DI-Net RPC realtime:data format
func TestPublishProjectUpdate(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// newMockServer
	srv := newWsconnMockServer(NewWsHandlerContext(ctx, nil))
	defer srv.Close()

	// Connect to the mockserver with a websocket client
	clnt, err := wsclnt.NewClient(srv.URL())
	require.Nil(t, err)
	defer clnt.Close()

	// Get the connect client from the list
	clients.mu.RLock()
	li := clients.list.Front()
	clients.mu.RUnlock()
	require.NotNil(t, li)
	require.NotNil(t, li.Value)
	c := li.Value.(*client)

	// Set device field subscriptions
	clients.mu.Lock()
	c.projectFields = map[uint64][]string{
		10: {"last_update", "project:counter", "project:status"},
	}
	clients.mu.Unlock()

	// Publish mocked redis event
	ev := redis.Event{Chan: "project", Msg: "10"}
	values := map[string]string{
		"last_update":     "1234",
		"project:counter": "{}",
		"project:status":  "{}",
		"project:info":    "{}", // Add a filtered field with value for testing filterFields
	}
	Publish(ev, values)

	// Read the RPC realtime:data message from the websocket
	msg, result, err := clnt.ReadRPCMsg()
	require.Nil(t, err)
	require.NotNil(t, msg)

	assert.Nil(t, msg.Error)
	assert.NotEqual(t, 0, msg.Time)
	assert.Equal(t, msg.Type, rpc.MsgTypePublish)
	assert.Equal(t, msg.ClassMethod, rpc.ClassMethodRealtimeData)
	assert.Equal(t, uint(10), msg.ProjectID)
	assert.JSONEq(t, result, `{"last_update":1234,"project:counter":{},"project:status":{}}`)
}