<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Integrations\Divi\Design;

use Brain\Monkey\Functions;
use InvalidArgumentException;
use LIT\MCP\Integrations\Divi\Design\DesignLock;
use LIT\MCP\Tests\Support\LockTable;
use LIT\MCP\Tests\Unit\TestCase;

/** Audits L5/L6: one shared lock for colors and theme options; atomic acquire and token-checked release. */
final class DesignLockTest extends TestCase
{
    private function table(): LockTable
    {
        return LockTable::install();
    }

    protected function tearDown(): void
    {
        unset($GLOBALS['wpdb']);
        parent::tearDown();
    }

    public function testAcquireIsExclusiveUntilReleased(): void
    {
        $db = $this->table();
        $lock = new DesignLock();

        self::assertTrue($lock->acquire('presets'));
        self::assertMatchesRegularExpression('/^\d+:[0-9a-f]{8}$/', $db->rows['lit_mcp_lock_presets']);
        self::assertFalse((new DesignLock())->acquire('presets'));
        self::assertTrue($lock->acquire('variables'), 'areas lock independently');

        $lock->release('presets');
        self::assertSame([], array_diff_key($db->rows, ['lit_mcp_lock_variables' => 1]));
        self::assertTrue((new DesignLock())->acquire('presets'));
    }

    /** Audit L5: both areas rewrite the whole et_divi array, so they exclude each other. */
    public function testColorsAndThemeOptionsShareOneLock(): void
    {
        $this->table();

        self::assertSame(DesignLock::option('colors'), DesignLock::option('theme_options'));
        self::assertTrue((new DesignLock())->acquire('colors'));
        self::assertFalse((new DesignLock())->acquire('theme_options'));
        self::assertTrue((new DesignLock())->acquire('variables'));
    }

    public function testAStaleLockIsTakenOverExactlyOnce(): void
    {
        $db = $this->table();
        $db->rows['lit_mcp_lock_presets'] = (time() - DesignLock::STALE_AFTER - 1) . ':old';

        self::assertTrue((new DesignLock())->acquire('presets'));
        self::assertGreaterThan(time() - 5, (int) $db->rows['lit_mcp_lock_presets']);
        self::assertFalse((new DesignLock())->acquire('presets'), 'the second taker sees a fresh lock');
    }

    /** Audit L6: a holder whose lock went stale and was taken over must not free the new holder's lock. */
    public function testReleaseOnlyDeletesTheOwnToken(): void
    {
        $db = $this->table();
        $old = new DesignLock();
        self::assertTrue($old->acquire('presets'));
        $db->rows['lit_mcp_lock_presets'] = (time() - DesignLock::STALE_AFTER - 1) . ':x';
        $new = new DesignLock();
        self::assertTrue($new->acquire('presets'));

        $old->release('presets');

        self::assertArrayHasKey('lit_mcp_lock_presets', $db->rows);
        self::assertFalse((new DesignLock())->acquire('presets'));
        $new->release('presets');
        self::assertArrayNotHasKey('lit_mcp_lock_presets', $db->rows);
    }

    public function testAFreshLockIsNotTakenOver(): void
    {
        $db = $this->table();
        $db->rows['lit_mcp_lock_presets'] = (time() - 10) . ':x';

        self::assertFalse((new DesignLock())->acquire('presets'));
    }

    public function testOptionNamesAndUnknownAreas(): void
    {
        self::assertSame('lit_mcp_lock_divi_options', DesignLock::option('theme_options'));
        self::assertSame('lit_mcp_lock_presets', DesignLock::option('presets'));

        $this->expectException(InvalidArgumentException::class);
        DesignLock::option('pages');
    }

    /**
     * Audit L5 (re-review): get_option('et_divi') comes from the object cache loaded at the start of the request
     * (autoload / alloptions). A writer that finished meanwhile is invisible until the lock holder drops that cache.
     */
    public function testTheLockHolderReadsEtDiviFreshNotFromTheRequestStartCache(): void
    {
        $db = $this->table();
        $stored = ['et_divi' => ['color' => 'alt'], 'et_divi_global_variables' => ['v' => 'alt']];
        $cache = [];
        // Like WordPress: every option is cached under its own key (not autoloaded ones) or in "alloptions".
        Functions\when('get_option')->alias(static function (string $name) use (&$stored, &$cache) {
            $key = 'options:' . $name;
            $cache[$key] ??= $stored[$name] ?? false;

            return $cache[$key];
        });
        Functions\when('wp_cache_flush_group')->alias(static function (string $group) use (&$cache): bool {
            foreach (array_keys($cache) as $key) {
                if (str_starts_with($key, $group . ':')) {
                    unset($cache[$key]);
                }
            }

            return true;
        });

        self::assertSame(['color' => 'alt'], get_option('et_divi'), 'request B cached the old array');
        self::assertSame(['v' => 'alt'], get_option('et_divi_global_variables'));
        $stored['et_divi'] = ['color' => 'neu']; // request A wrote and released meanwhile
        $stored['et_divi_global_variables'] = ['v' => 'neu'];

        self::assertTrue((new DesignLock())->acquire('colors'));
        self::assertSame(['color' => 'neu'], get_option('et_divi'));
        self::assertSame(['v' => 'neu'], get_option('et_divi_global_variables'), 'also options that are not autoloaded');
        self::assertNotSame([], $db->rows);
    }
}