<?php

use App\Console\Commands\OnlineSchemaChange;
use Illuminate\Support\Facades\Process;
use Symfony\Component\Console\Input\ArrayInput;
use Symfony\Component\Console\Input\InputDefinition;
use Symfony\Component\Console\Input\InputOption;
use Tests\TestCase;

/**
 * `db:online-alter` baut den Aufruf für pt-online-schema-change. Das Tool
 * selbst wird hier nicht ausgeführt — geprüft werden die Schutzmechanismen
 * und die Zusammenstellung der Argumente, weil ein falsches Flag auf der
 * Live-Datenbank teuer ist.
 */
function ptOscArguments(array $overrides = []): array
{
    $config = array_merge([
        'driver' => 'mysql',
        'host' => 'db.example.test',
        'port' => 3306,
        'database' => 'pressekonto',
        'username' => 'app',
        'password' => 'geheim',
    ], $overrides);

    $command = new OnlineSchemaChange;
    $command->setLaravel(app());

    // Ohne --execute gilt der Trockenlauf; die Option wird hier gesetzt,
    // weil buildArguments() sie liest.
    (fn () => $this->input = new ArrayInput(
        ['--execute' => true],
        new InputDefinition([
            new InputOption('execute', null, InputOption::VALUE_NONE),
            new InputOption('drop-old-table', null, InputOption::VALUE_NONE),
        ]),
    ))->call($command);

    return $command->buildArguments($config, 'press_releases', 'ADD COLUMN gone_at TIMESTAMP NULL', '/tmp/creds.cnf');
}

test('the generated call carries the flags that keep the table writable', function () {
    $arguments = ptOscArguments();

    expect($arguments)
        ->toContain('--alter=ADD COLUMN gone_at TIMESTAMP NULL')
        // 17 Fremdschlüssel zeigen auf die beiden großen Tabellen. Das
        // schnellere `drop_swap` wäre kurzzeitig inkonsistent.
        ->toContain('--alter-foreign-keys-method=rebuild_constraints')
        // pt-osc darf den laufenden Betrieb nicht ausbremsen.
        ->toContain('--set-vars=lock_wait_timeout=60,innodb_lock_wait_timeout=1')
        ->toContain('--max-load=Threads_running=40')
        ->toContain('--critical-load=Threads_running=100')
        ->toContain('--execute')
        ->not->toContain('--dry-run');
});

test('the credentials never appear on the command line', function () {
    $arguments = ptOscArguments();
    $line = implode(' ', $arguments);

    // Über `ps` ist die Kommandozeile für jeden Benutzer des Servers lesbar.
    expect($line)
        ->not->toContain('geheim')
        ->not->toContain('app')
        ->toContain('F=/tmp/creds.cnf');
});

test('the connection details land in the dsn', function () {
    $arguments = ptOscArguments();

    expect(end($arguments))
        ->toContain('h=db.example.test')
        ->toContain('P=3306')
        ->toContain('D=pressekonto')
        ->toContain('t=press_releases');
});

test('the old table is kept unless dropping it is requested', function () {
    expect(ptOscArguments())->toContain('--no-drop-old-table');
});

test('a non mysql connection is refused instead of pretending to work', function () {
    /** @var TestCase $this */
    Process::fake();

    // Die Testsuite läuft auf SQLite — dort richtet pt-osc nichts aus.
    $this->artisan('db:online-alter', ['table' => 'users', 'alter' => 'ADD COLUMN foo INT NULL'])
        ->expectsOutputToContain('kein MySQL')
        ->assertFailed();

    Process::assertNothingRan();
});

test('an unreachable database reports plainly instead of throwing', function () {
    /** @var TestCase $this */
    Process::fake();

    config()->set('database.connections.fake_mysql', [
        'driver' => 'mysql',
        'host' => 'db.example.invalid',
        'database' => 'pressekonto',
        'username' => 'app',
        'password' => 'geheim',
    ]);

    $this->artisan('db:online-alter', [
        'table' => 'press_releases',
        'alter' => 'ADD COLUMN foo INT NULL',
        '--connection' => 'fake_mysql',
    ])
        ->expectsOutputToContain('nicht erreichbar')
        ->assertFailed();

    Process::assertNothingRan();
});