1 files changed, 510 insertions, 0 deletions
diff --git a/internal/app/app_test.go b/internal/app/app_test.go
new file mode 100644
index 0000000..e770060
--- /dev/null
+++ b/internal/app/app_test.go
@@ -0,0 +1,510 @@
+package app
+
+import (
+	"context"
+	"io"
+	"log/slog"
+	"strings"
+	"testing"
+	"time"
+
+	"cep.is/telegrambot/internal/config"
+	"cep.is/telegrambot/internal/telegram"
+)
+
+func testConfig(tg *fakeTelegram, api *fakeCEPIS) config.Config {
+	cfg := config.Defaults()
+	cfg.Token = fakeToken
+	cfg.TelegramAPIBaseURL = tg.URL()
+	cfg.CepisBaseURL = api.URL()
+	cfg.PollTimeout = time.Second
+	cfg.RequestTimeout = 2 * time.Second
+	cfg.MaxAttempts = 2
+	cfg.BackoffBase = 5 * time.Millisecond
+	cfg.BackoffMax = 20 * time.Millisecond
+	cfg.ShutdownGrace = 3 * time.Second
+	return cfg
+}
+
+func quietLogger() *slog.Logger {
+	return slog.New(slog.NewJSONHandler(io.Discard, &slog.HandlerOptions{Level: slog.LevelError}))
+}
+
+type running struct {
+	app  *App
+	stop context.CancelFunc
+	done chan error
+}
+
+func (r *running) wait(t *testing.T) {
+	t.Helper()
+	r.stop()
+	select {
+	case err := <-r.done:
+		r.done <- err
+	case <-time.After(10 * time.Second):
+		t.Fatal("the bot did not shut down")
+	}
+}
+
+func start(t *testing.T, cfg config.Config) *running {
+	t.Helper()
+	ctx, cancel := context.WithCancel(context.Background())
+
+	application, err := New(ctx, cfg, quietLogger())
+	if err != nil {
+		cancel()
+		t.Fatalf("New: %v", err)
+	}
+
+	done := make(chan error, 1)
+	go func() { done <- application.Run(ctx) }()
+
+	r := &running{app: application, stop: cancel, done: done}
+	t.Cleanup(func() {
+		cancel()
+		select {
+		case <-done:
+		case <-time.After(10 * time.Second):
+		}
+	})
+	return r
+}
+
+func privateMessage(id int64, userID int64, text string) telegram.Update {
+	return telegram.Update{
+		UpdateID: id,
+		Message: &telegram.Message{
+			MessageID: id,
+			From:      &telegram.User{ID: userID, FirstName: "Tester"},
+			Chat:      telegram.Chat{ID: userID, Type: "private"},
+			Text:      text,
+		},
+	}
+}
+
+func groupMessage(id int64, text string) telegram.Update {
+	return telegram.Update{
+		UpdateID: id,
+		Message: &telegram.Message{
+			MessageID: id,
+			From:      &telegram.User{ID: 777, FirstName: "Tester"},
+			Chat:      telegram.Chat{ID: -100200, Type: "supergroup", Title: "Grupo"},
+			Text:      text,
+		},
+	}
+}
+
+func channelPost(id int64, text string) telegram.Update {
+	return telegram.Update{
+		UpdateID: id,
+		ChannelPost: &telegram.Message{
+			MessageID: id,
+			Chat:      telegram.Chat{ID: -100999, Type: "channel", Title: "Canal"},
+			Text:      text,
+		},
+	}
+}
+
+func inlineQuery(id int64, userID int64, query string) telegram.Update {
+	return telegram.Update{
+		UpdateID: id,
+		InlineQuery: &telegram.InlineQuery{
+			ID:    "iq-" + query,
+			From:  telegram.User{ID: userID, FirstName: "Tester"},
+			Query: query,
+		},
+	}
+}
+
+func waitForMessages(t *testing.T, tg *fakeTelegram, n int) []telegram.SendMessageRequest {
+	t.Helper()
+	waitFor(t, "messages", 10*time.Second, func() bool { return len(tg.sentMessages()) >= n })
+	return tg.sentMessages()
+}
+
+func TestGetMeIdentifiesTheBot(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	r := start(t, testConfig(tg, api))
+	if r.app.Username() != fakeUsername {
+		t.Fatalf("username = %q, want %q", r.app.Username(), fakeUsername)
+	}
+}
+
+func TestPrivateBareCEP(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(privateMessage(1, 555, "01001-000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "Praça da Sé") {
+		t.Fatalf("reply does not carry the address: %q", sent[0].Text)
+	}
+	if sent[0].ChatID != 555 {
+		t.Fatalf("chat id = %d, want 555", sent[0].ChatID)
+	}
+	if sent[0].ReplyParameters != nil {
+		t.Fatal("a private answer should not quote the message")
+	}
+}
+
+func TestGroupCommand(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(groupMessage(1, "/cep 01001000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "Praça da Sé") {
+		t.Fatalf("reply does not carry the address: %q", sent[0].Text)
+	}
+	if sent[0].ReplyParameters == nil || sent[0].ReplyParameters.MessageID != 1 {
+		t.Fatal("a group answer should quote the message that asked")
+	}
+}
+
+func TestGroupCommandAddressedToTheBot(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(groupMessage(1, "/cep@"+fakeUsername+" 01001000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "Praça da Sé") {
+		t.Fatalf("reply does not carry the address: %q", sent[0].Text)
+	}
+}
+
+func TestCommandAddressedToAnotherBotIsIgnored(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(
+		groupMessage(1, "/cep@outrobot 01001000"),
+		groupMessage(2, "/cep 01001000"),
+	)
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	time.Sleep(200 * time.Millisecond)
+	if got := len(tg.sentMessages()); got != 1 {
+		t.Fatalf("sent %d messages, want exactly 1", got)
+	}
+	if sent[0].ReplyParameters.MessageID != 2 {
+		t.Fatalf("answered message %d, want 2", sent[0].ReplyParameters.MessageID)
+	}
+}
+
+func TestChannelPost(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(channelPost(1, "/cep@"+fakeUsername+" 01001000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if sent[0].ChatID != -100999 {
+		t.Fatalf("chat id = %d, want -100999", sent[0].ChatID)
+	}
+	if !strings.Contains(sent[0].Text, "Praça da Sé") {
+		t.Fatalf("reply does not carry the address: %q", sent[0].Text)
+	}
+}
+
+func TestGroupTextWithoutCommandIsIgnored(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(
+		groupMessage(1, "01001000"),
+		groupMessage(2, "/cep 01001000"),
+	)
+	start(t, testConfig(tg, api))
+
+	waitForMessages(t, tg, 1)
+	time.Sleep(200 * time.Millisecond)
+	if got := len(tg.sentMessages()); got != 1 {
+		t.Fatalf("sent %d messages, want exactly 1", got)
+	}
+}
+
+func TestInlineQuery(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(inlineQuery(1, 555, "01001000"))
+	start(t, testConfig(tg, api))
+
+	waitFor(t, "inline answer", 10*time.Second, func() bool { return len(tg.inlineAnswers()) >= 1 })
+	answer := tg.inlineAnswers()[0]
+	if len(answer.Results) != 1 {
+		t.Fatalf("got %d results, want 1", len(answer.Results))
+	}
+	result := answer.Results[0]
+	if result.Type != "article" {
+		t.Fatalf("result type = %q, want article", result.Type)
+	}
+	if !strings.Contains(result.Title, "01001-000") {
+		t.Fatalf("title = %q", result.Title)
+	}
+	if !strings.Contains(result.InputMessageContent.MessageText, "Praça da Sé") {
+		t.Fatalf("message content = %q", result.InputMessageContent.MessageText)
+	}
+}
+
+func TestInlineQueryWhileStillTypingCostsNothing(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(inlineQuery(1, 555, "0100"))
+	start(t, testConfig(tg, api))
+
+	waitFor(t, "inline answer", 10*time.Second, func() bool { return len(tg.inlineAnswers()) >= 1 })
+	if got := len(tg.inlineAnswers()[0].Results); got != 0 {
+		t.Fatalf("got %d results for a partial CEP, want 0", got)
+	}
+	if got := api.requestCount(); got != 0 {
+		t.Fatalf("the API was called %d times for a partial CEP, want 0", got)
+	}
+}
+
+func TestStartAndHelp(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(
+		privateMessage(1, 555, "/start"),
+		privateMessage(2, 555, "/help"),
+	)
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 2)
+	for _, message := range sent {
+		for _, needed := range []string{"https://cep.is", "/cep 01001000", "@" + fakeUsername} {
+			if !strings.Contains(message.Text, needed) {
+				t.Fatalf("help text is missing %q: %q", needed, message.Text)
+			}
+		}
+	}
+	if !strings.Contains(sent[0].Text, "Olá") {
+		t.Fatalf("/start should greet: %q", sent[0].Text)
+	}
+}
+
+func TestMalformedCEP(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(groupMessage(1, "/cep 123"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "inválido") {
+		t.Fatalf("reply = %q, want an invalid-CEP message", sent[0].Text)
+	}
+	if got := api.requestCount(); got != 0 {
+		t.Fatalf("the API was called %d times for a malformed CEP, want 0", got)
+	}
+}
+
+func TestCEPNotFound(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(privateMessage(1, 555, "99999999"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "não encontrado") {
+		t.Fatalf("reply = %q, want a not-found message", sent[0].Text)
+	}
+}
+
+func TestAPIServerError(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(privateMessage(1, 555, "50000000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "respondeu com erro") {
+		t.Fatalf("reply = %q, want a server-error message", sent[0].Text)
+	}
+}
+
+func TestAPINetworkFailure(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	cfg := testConfig(tg, api)
+	cfg.MaxAttempts = 1
+	api.server.Close()
+
+	tg.push(privateMessage(1, 555, "01001000"))
+	start(t, cfg)
+
+	sent := waitForMessages(t, tg, 1)
+	if !strings.Contains(sent[0].Text, "Não consegui falar com a cep.is") {
+		t.Fatalf("reply = %q, want a network-failure message", sent[0].Text)
+	}
+}
+
+func TestRateLimiterLimits(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+
+	var updates []telegram.Update
+	for i := 1; i <= 8; i++ {
+		updates = append(updates, privateMessage(int64(i), 555, "01001000"))
+	}
+	tg.push(updates...)
+	start(t, testConfig(tg, api))
+
+	waitFor(t, "the limiter to kick in", 10*time.Second, func() bool {
+		for _, message := range tg.sentMessages() {
+			if strings.Contains(message.Text, "muitas consultas") {
+				return true
+			}
+		}
+		return false
+	})
+	time.Sleep(300 * time.Millisecond)
+
+	sent := tg.sentMessages()
+	addresses, warnings := 0, 0
+	for _, message := range sent {
+		switch {
+		case strings.Contains(message.Text, "Praça da Sé"):
+			addresses++
+		case strings.Contains(message.Text, "muitas consultas"):
+			warnings++
+		}
+	}
+	if addresses != 5 {
+		t.Fatalf("answered %d lookups, want 5 (the burst)", addresses)
+	}
+	if warnings != 1 {
+		t.Fatalf("sent %d warnings, want exactly 1 per window", warnings)
+	}
+	if got := api.requestCount(); got != 5 {
+		t.Fatalf("the API saw %d requests, want 5", got)
+	}
+}
+
+func TestTelegram429RetryAfterIsHonoured(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.failNextSends(cannedFailure{
+		status: 429, code: 429, description: "Too Many Requests: retry after 1", retryAfter: 1,
+	})
+	tg.push(privateMessage(1, 555, "01001000"))
+
+	started := time.Now()
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	elapsed := time.Since(started)
+	if elapsed < time.Second {
+		t.Fatalf("retried after %v, want at least the 1s Telegram asked for", elapsed)
+	}
+	if !strings.Contains(sent[0].Text, "Praça da Sé") {
+		t.Fatalf("reply = %q", sent[0].Text)
+	}
+}
+
+func TestOffsetAdvancesAcrossPolls(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(privateMessage(10, 555, "01001000"))
+	r := start(t, testConfig(tg, api))
+
+	waitForMessages(t, tg, 1)
+	tg.push(privateMessage(11, 555, "99999999"))
+	waitForMessages(t, tg, 2)
+
+	waitFor(t, "the second offset to be confirmed", 5*time.Second, func() bool {
+		for _, offset := range tg.requestedOffsets() {
+			if offset == 12 {
+				return true
+			}
+		}
+		return false
+	})
+
+	offsets := tg.requestedOffsets()
+	if offsets[0] != 0 {
+		t.Fatalf("first poll asked for offset %d, want 0", offsets[0])
+	}
+	seen11 := false
+	for _, offset := range offsets {
+		if offset == 11 {
+			seen11 = true
+		}
+		if offset > 12 {
+			t.Fatalf("offset ran past the last update: %v", offsets)
+		}
+	}
+	if !seen11 {
+		t.Fatalf("offset never confirmed the first update: %v", offsets)
+	}
+	r.wait(t)
+	if r.app.Offset() != 12 {
+		t.Fatalf("final offset = %d, want 12", r.app.Offset())
+	}
+}
+
+func TestGracefulShutdownKeepsTheOffset(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(
+		privateMessage(1, 555, "01001000"),
+		privateMessage(2, 555, "99999999"),
+	)
+	r := start(t, testConfig(tg, api))
+
+	waitForMessages(t, tg, 2)
+	r.wait(t)
+
+	offsets := tg.requestedOffsets()
+	last := offsets[len(offsets)-1]
+	if last != 3 {
+		t.Fatalf("last offset sent was %d, want 3 so the handled updates stay confirmed", last)
+	}
+	if got := tg.pendingCount(); got != 0 {
+		t.Fatalf("%d updates are still unconfirmed and would be replayed", got)
+	}
+}
+
+func TestPrecisionChangesTheReply(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(
+		privateMessage(1, 555, "01001000"),
+		privateMessage(2, 556, "76200000"),
+	)
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 2)
+	street, municipality := sent[0].Text, sent[1].Text
+
+	if street == municipality {
+		t.Fatal("both precisions produced the same reply")
+	}
+	if !strings.Contains(street, "openstreetmap.org") {
+		t.Fatalf("a street-level CEP should carry a map link: %q", street)
+	}
+	if !strings.Contains(street, "128 m") {
+		t.Fatalf("a street-level CEP should state its radius: %q", street)
+	}
+
+	if strings.Contains(municipality, "openstreetmap.org") {
+		t.Fatalf("a municipality CEP must never carry a map link: %q", municipality)
+	}
+	if !strings.Contains(municipality, "CEP geral de município") {
+		t.Fatalf("a municipality CEP must say so: %q", municipality)
+	}
+	if !strings.Contains(municipality, "18,4 km") {
+		t.Fatalf("a municipality CEP must state its radius: %q", municipality)
+	}
+	if !strings.Contains(municipality, "centroide") {
+		t.Fatalf("a municipality CEP must name the point: %q", municipality)
+	}
+}
+
+func TestAddressWithoutCoordinate(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	tg.push(privateMessage(1, 555, "29902000"))
+	start(t, testConfig(tg, api))
+
+	sent := waitForMessages(t, tg, 1)
+	if strings.Contains(sent[0].Text, "openstreetmap.org") {
+		t.Fatalf("no coordinate should mean no map link: %q", sent[0].Text)
+	}
+	if !strings.Contains(sent[0].Text, "Sem coordenada") {
+		t.Fatalf("reply = %q", sent[0].Text)
+	}
+}
+
+func TestBadTokenFailsAtStartup(t *testing.T) {
+	tg, api := newFakeTelegram(t), newFakeCEPIS(t)
+	cfg := testConfig(tg, api)
+	cfg.Token = "424242:a-different-token"
+
+	if _, err := New(context.Background(), cfg, quietLogger()); err == nil {
+		t.Fatal("New accepted a token the API rejects")
+	}
+}