package main

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

	"github.com/stretchr/testify/require"
	"go.mau.fi/whatsmeow/types/events"
)

func TestWhatsAppStatusFollowsTheConnection(t *testing.T) {
	dir := t.TempDir()
	whatsappTestSession(t, dir, true)
	clock := newTestClock()
	fake := &WhatsAppFake{
		connected: make(chan struct{}),
	}

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

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

	ctx, cancel := context.WithCancel(t.Context())
	done := make(chan struct{})
	go func() {
		defer close(done)

		whatsapp.Run(ctx)
	}()

	t.Cleanup(func() {
		cancel()
		<-done
	})

	<-fake.connected
	require.Equal(t, "WhatsApp is linked and not connected yet.", whatsapp.Status())

	require.True(t, fake.Emit(&events.Connected{}))
	require.Equal(t, "WhatsApp is linked and connected since 2026-01-01 12:00.", whatsapp.Status())

	clock.now = clock.now.Add(20 * time.Minute)
	require.True(t, fake.Emit(&events.Disconnected{}))
	clock.now = clock.now.Add(time.Minute)
	require.True(t, fake.Emit(&events.Disconnected{}))
	require.Equal(t, "WhatsApp is linked and disconnected since 2026-01-01 12:20. The last connection started at 2026-01-01 12:00.", whatsapp.Status())
}

func TestWhatsAppStatusOfAFirstConnectionThatFailed(t *testing.T) {
	dir := t.TempDir()
	whatsappTestSession(t, dir, true)
	whatsapp, fake := whatsappStartTest(t, dir)

	ctx, cancel := context.WithCancel(t.Context())
	done := make(chan struct{})
	go func() {
		defer close(done)

		whatsapp.Run(ctx)
	}()

	t.Cleanup(func() {
		cancel()
		<-done
	})

	<-fake.connected
	require.True(t, fake.Emit(&events.Disconnected{}))
	require.Equal(t, "WhatsApp is linked and disconnected since 2026-01-01 12:00.", whatsapp.Status())
}

func TestWhatsAppIsNotLinkedWithoutALinkedDevice(t *testing.T) {
	testCases := []struct {
		name    string
		session func(t *testing.T, dir string)
	}{
		{
			name: "no session file",
			session: func(t *testing.T, dir string) {
			},
		},
		{
			name: "a session of a pairing that did not end",
			session: func(t *testing.T, dir string) {
				whatsappTestSession(t, dir, false)
			},
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			dir := t.TempDir()
			tc.session(t, dir)
			whatsapp, _ := whatsappStartTest(t, dir)
			require.Equal(t, "WhatsApp is not linked.", whatsapp.Status())
		})
	}
}

func TestWhatsAppRefusesASessionThatOthersCanRead(t *testing.T) {
	dir := t.TempDir()
	whatsappTestSession(t, dir, true)
	require.NoError(t, os.Chmod(filepath.Join(dir, whatsappDirName, whatsappSessionFileName), 0o644))

	_, err := openWhatsApp(t.Context(), dir, time.Now, log.New(io.Discard, "", 0), whatsappNewClient)
	require.EqualError(t, err, "whatsapp/session.db holds the WhatsApp session, so its mode must be 0600")
}

func TestWhatsAppCommandsAnswerOnlyTheClientThatAsked(t *testing.T) {
	server := newModelFake(t)
	telegram := newTelegramFake(t)
	bot, _ := telegramStartTestBot(t, telegram)
	socket := daemonStartTestWithBot(t, server, bot)
	asking := terminalStartTestClient(t, socket)
	other := terminalStartTestClient(t, socket)
	asking.WaitFor(t, "[connected to OneChat]")
	other.WaitFor(t, "[connected to OneChat]")

	asking.Type("/whatsapp status")
	asking.WaitFor(t, "WhatsApp is not linked.")
	asking.Type(" /whatsapp  unknown ")
	asking.WaitFor(t, whatsappUsage)

	telegram.Add(TelegramUpdate{
		UpdateID: 1,
		Message:  telegramOwnerMessage("/whatsapp status"),
	})

	telegramWaitForSent(t, telegram, "WhatsApp is not linked.")
	require.Equal(t, []string{"WhatsApp is not linked."}, telegram.Sent())
	require.Equal(t, "[connected to OneChat]\n", other.Output())
	require.Zero(t, server.Calls())
}

func TestWhatsAppCommandArgs(t *testing.T) {
	testCases := []struct {
		name  string
		line  string
		args  string
		found bool
	}{
		{
			name:  "a command with its arguments",
			line:  " /whatsapp  pair +1 555 ",
			args:  "pair +1 555",
			found: true,
		},
		{
			name:  "the command alone",
			line:  "/whatsapp",
			args:  "",
			found: true,
		},
		{
			name:  "a word that starts with the command",
			line:  "/whatsappstatus",
			args:  "",
			found: false,
		},
		{
			name:  "a message that names the command",
			line:  "what does /whatsapp status do?",
			args:  "",
			found: false,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			args, found := whatsappCommandArgs(tc.line)
			require.Equal(t, tc.args, args)
			require.Equal(t, tc.found, found)
		})
	}
}