<?php

namespace Tests\Auth;

use BookStack\Auth\Access\LoginService;
use BookStack\Auth\Access\Mfa\MfaValue;
use BookStack\Auth\Access\Mfa\TotpService;
use BookStack\Auth\Role;
use BookStack\Auth\User;
use BookStack\Exceptions\StoppedAuthenticationException;
use Illuminate\Support\Facades\Hash;
use PragmaRX\Google2FA\Google2FA;
use Tests\TestCase;
use Tests\TestResponse;

class MfaVerificationTest extends TestCase
{
    public function test_totp_verification()
    {
        [$user, $secret, $loginResp] = $this->startTotpLogin();
        $loginResp->assertRedirect('/mfa/verify');

        $resp = $this->get('/mfa/verify');
        $resp->assertSee('Verify Access');
        $resp->assertSee('Enter the code, generated using your mobile app, below:');
        $this->withHtml($resp)->assertElementExists('form[action$="/mfa/totp/verify"] input[name="code"][autofocus]');

        $google2fa = new Google2FA();
        $resp = $this->post('/mfa/totp/verify', [
            'code' => $google2fa->getCurrentOtp($secret),
        ]);
        $resp->assertRedirect('/');
        $this->assertEquals($user->id, auth()->user()->id);
    }

    public function test_totp_verification_fails_on_missing_invalid_code()
    {
        [$user, $secret, $loginResp] = $this->startTotpLogin();

        $resp = $this->get('/mfa/verify');
        $resp = $this->post('/mfa/totp/verify', [
            'code' => '',
        ]);
        $resp->assertRedirect('/mfa/verify');

        $resp = $this->get('/mfa/verify');
        $resp->assertSeeText('The code field is required.');
        $this->assertNull(auth()->user());

        $resp = $this->post('/mfa/totp/verify', [
            'code' => '123321',
        ]);
        $resp->assertRedirect('/mfa/verify');
        $resp = $this->get('/mfa/verify');

        $resp->assertSeeText('The provided code is not valid or has expired.');
        $this->assertNull(auth()->user());
    }

    public function test_backup_code_verification()
    {
        [$user, $codes, $loginResp] = $this->startBackupCodeLogin();
        $loginResp->assertRedirect('/mfa/verify');

        $resp = $this->get('/mfa/verify');
        $resp->assertSee('Verify Access');
        $resp->assertSee('Backup Code');
        $resp->assertSee('Enter one of your remaining backup codes below:');
        $this->withHtml($resp)->assertElementExists('form[action$="/mfa/backup_codes/verify"] input[name="code"]');

        $resp = $this->post('/mfa/backup_codes/verify', [
            'code' => $codes[1],
        ]);

        $resp->assertRedirect('/');
        $this->assertEquals($user->id, auth()->user()->id);
        // Ensure code no longer exists in available set
        $userCodes = MfaValue::getValueForUser($user, MfaValue::METHOD_BACKUP_CODES);
        $this->assertStringNotContainsString($codes[1], $userCodes);
        $this->assertStringContainsString($codes[0], $userCodes);
    }

    public function test_backup_code_verification_fails_on_missing_or_invalid_code()
    {
        [$user, $codes, $loginResp] = $this->startBackupCodeLogin();

        $resp = $this->get('/mfa/verify');
        $resp = $this->post('/mfa/backup_codes/verify', [
            'code' => '',
        ]);
        $resp->assertRedirect('/mfa/verify');

        $resp = $this->get('/mfa/verify');
        $resp->assertSeeText('The code field is required.');
        $this->assertNull(auth()->user());

        $resp = $this->post('/mfa/backup_codes/verify', [
            'code' => 'ab123-ab456',
        ]);
        $resp->assertRedirect('/mfa/verify');

        $resp = $this->get('/mfa/verify');
        $resp->assertSeeText('The provided code is not valid or has already been used.');
        $this->assertNull(auth()->user());
    }

    public function test_backup_code_verification_fails_on_attempted_code_reuse()
    {
        [$user, $codes, $loginResp] = $this->startBackupCodeLogin();

        $this->post('/mfa/backup_codes/verify', [
            'code' => $codes[0],
        ]);
        $this->assertNotNull(auth()->user());
        auth()->logout();
        session()->flush();

        $this->post('/login', ['email' => $user->email, 'password' => 'password']);
        $this->get('/mfa/verify');
        $resp = $this->post('/mfa/backup_codes/verify', [
            'code' => $codes[0],
        ]);
        $resp->assertRedirect('/mfa/verify');
        $this->assertNull(auth()->user());

        $resp = $this->get('/mfa/verify');
        $resp->assertSeeText('The provided code is not valid or has already been used.');
    }

    public function test_backup_code_verification_shows_warning_when_limited_codes_remain()
    {
        [$user, $codes, $loginResp] = $this->startBackupCodeLogin(['abc12-def45', 'abc12-def46']);

        $resp = $this->post('/mfa/backup_codes/verify', [
            'code' => $codes[0],
        ]);
        $resp = $this->followRedirects($resp);
        $resp->assertSeeText('You have less than 5 backup codes remaining, Please generate and store a new set before you run out of codes to prevent being locked out of your account.');
    }

    public function test_both_mfa_options_available_if_set_on_profile()
    {
        $user = $this->users->editor();
        $user->password = Hash::make('password');
        $user->save();

        MfaValue::upsertWithValue($user, MfaValue::METHOD_TOTP, 'abc123');
        MfaValue::upsertWithValue($user, MfaValue::METHOD_BACKUP_CODES, '["abc12-def456"]');

        /** @var TestResponse $mfaView */
        $mfaView = $this->followingRedirects()->post('/login', [
            'email'    => $user->email,
            'password' => 'password',
        ]);

        // Totp shown by default
        $this->withHtml($mfaView)->assertElementExists('form[action$="/mfa/totp/verify"] input[name="code"]');
        $this->withHtml($mfaView)->assertElementContains('a[href$="/mfa/verify?method=backup_codes"]', 'Verify using a backup code');

        // Ensure can view backup_codes view
        $resp = $this->get('/mfa/verify?method=backup_codes');
        $this->withHtml($resp)->assertElementExists('form[action$="/mfa/backup_codes/verify"] input[name="code"]');
        $this->withHtml($resp)->assertElementContains('a[href$="/mfa/verify?method=totp"]', 'Verify using a mobile app');
    }

    public function test_mfa_required_with_no_methods_leads_to_setup()
    {
        $user = $this->users->editor();
        $user->password = Hash::make('password');
        $user->save();
        /** @var Role $role */
        $role = $user->roles->first();
        $role->mfa_enforced = true;
        $role->save();

        $this->assertDatabaseMissing('mfa_values', [
            'user_id' => $user->id,
        ]);

        /** @var TestResponse $resp */
        $resp = $this->followingRedirects()->post('/login', [
            'email'    => $user->email,
            'password' => 'password',
        ]);

        $resp->assertSeeText('No Methods Configured');
        $this->withHtml($resp)->assertElementContains('a[href$="/mfa/setup"]', 'Configure');

        $this->get('/mfa/backup_codes/generate');
        $resp = $this->post('/mfa/backup_codes/confirm');
        $resp->assertRedirect('/login');
        $this->assertDatabaseHas('mfa_values', [
            'user_id' => $user->id,
        ]);

        $resp = $this->get('/login');
        $resp->assertSeeText('Multi-factor method configured, Please now login again using the configured method.');

        $resp = $this->followingRedirects()->post('/login', [
            'email'    => $user->email,
            'password' => 'password',
        ]);
        $resp->assertSeeText('Enter one of your remaining backup codes below:');
    }

    public function test_mfa_setup_route_access()
    {
        $routes = [
            ['get', '/mfa/setup'],
            ['get', '/mfa/totp/generate'],
            ['post', '/mfa/totp/confirm'],
            ['get', '/mfa/backup_codes/generate'],
            ['post', '/mfa/backup_codes/confirm'],
        ];

        // Non-auth access
        foreach ($routes as [$method, $path]) {
            $resp = $this->call($method, $path);
            $resp->assertRedirect('/login');
        }

        // Attempted login user, who has configured mfa, access
        // Sets up user that has MFA required after attempted login.
        $loginService = $this->app->make(LoginService::class);
        $user = $this->users->editor();
        /** @var Role $role */
        $role = $user->roles->first();
        $role->mfa_enforced = true;
        $role->save();

        try {
            $loginService->login($user, 'testing');
        } catch (StoppedAuthenticationException $e) {
        }
        $this->assertNotNull($loginService->getLastLoginAttemptUser());

        MfaValue::upsertWithValue($user, MfaValue::METHOD_BACKUP_CODES, '[]');
        foreach ($routes as [$method, $path]) {
            $resp = $this->call($method, $path);
            $resp->assertRedirect('/login');
        }
    }

    public function test_login_mfa_interception_does_not_log_error()
    {
        $logHandler = $this->withTestLogger();

        [$user, $secret, $loginResp] = $this->startTotpLogin();

        $loginResp->assertRedirect('/mfa/verify');
        $this->assertFalse($logHandler->hasErrorRecords());
    }

    /**
     * @return array<User, string, TestResponse>
     */
    protected function startTotpLogin(): array
    {
        $secret = $this->app->make(TotpService::class)->generateSecret();
        $user = $this->users->editor();
        $user->password = Hash::make('password');
        $user->save();
        MfaValue::upsertWithValue($user, MfaValue::METHOD_TOTP, $secret);
        $loginResp = $this->post('/login', [
            'email'    => $user->email,
            'password' => 'password',
        ]);

        return [$user, $secret, $loginResp];
    }

    /**
     * @return array<User, string, TestResponse>
     */
    protected function startBackupCodeLogin($codes = ['kzzu6-1pgll', 'bzxnf-plygd', 'bwdsp-ysl51', '1vo93-ioy7n', 'lf7nw-wdyka', 'xmtrd-oplac']): array
    {
        $user = $this->users->editor();
        $user->password = Hash::make('password');
        $user->save();
        MfaValue::upsertWithValue($user, MfaValue::METHOD_BACKUP_CODES, json_encode($codes));
        $loginResp = $this->post('/login', [
            'email'    => $user->email,
            'password' => 'password',
        ]);

        return [$user, $codes, $loginResp];
    }
}