<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Server;

use Brain\Monkey\Filters;
use Brain\Monkey\Functions;
use LIT\MCP\Abilities\Ability;
use LIT\MCP\Abilities\ExposurePolicy;
use LIT\MCP\Guides\InstructionsBuilder;
use LIT\MCP\Integrations\Integration;
use LIT\MCP\Integrations\IntegrationRegistry;
use LIT\MCP\Server\ServerRegistrar;
use LIT\MCP\Tests\Unit\TestCase;
use Mockery;
use WPMedia\MCP\OAuth\Transport\ServerRegistrar as OAuthServerRegistrar;

final class ServerRegistrarTest extends TestCase
{
    protected function tearDown(): void
    {
        unset($GLOBALS['wp_filter']);
        parent::tearDown();
    }

    private function registry(): IntegrationRegistry
    {
        $direct = Mockery::mock(Ability::class);
        $direct->allows('name')->andReturn('lit/guide');
        $direct->allows('isDirect')->andReturn(true);
        $indirect = Mockery::mock(Ability::class);
        $indirect->allows('name')->andReturn('lit/rare-tool');
        $indirect->allows('isDirect')->andReturn(false);
        $indirect->allows('annotations')->andReturn([]);

        $core = Mockery::mock(Integration::class);
        $core->allows('id')->andReturn('core');
        $core->allows('isAvailable')->andReturn(true);
        $core->allows('abilities')->andReturn([$direct, $indirect]);

        return new IntegrationRegistry($core);
    }

    private function instructions(): InstructionsBuilder
    {
        // InstructionsBuilder is final (not mockable) and pure – use the real one.
        return new InstructionsBuilder($this->registry());
    }

    public function testServerUsesOauthRouteDirectToolsPlusMetaToolsAndInstructions(): void
    {
        $args = (new ServerRegistrar($this->registry(), $this->instructions(), static fn () => true))->serverArguments();

        self::assertSame('mcp-oauth-server', $args['id']);
        self::assertSame('mcp', $args['namespace']);
        self::assertSame('mcp-oauth-server', $args['route']);
        self::assertStringContainsString('Aktive Integrationen: core', $args['description']);
        self::assertSame(
            ['lit/guide', 'mcp-adapter/discover-abilities', 'mcp-adapter/get-ability-info', 'mcp-adapter/execute-ability'],
            $args['tools']
        );
        self::assertNotContains('lit/rare-tool', $args['tools']);
    }

    public function testExposurePolicyDecidesWhichToolsAreDirect(): void
    {
        // Deviation from the brief: the brief's original test demoted lit/guide to
        // indirect, but the controller's fixed constraint for this task is that
        // lit/guide can neither be disabled nor made indirect (see ExposurePolicy::
        // REQUIRED / ExposurePolicyTest::testGuideCanNeitherBeDisabledNorMadeIndirect).
        // Using a demotable direct ability here instead proves the same thing: the
        // policy, not Ability::isDirect(), decides the tool list.
        $optional = Mockery::mock(Ability::class);
        $optional->allows('name')->andReturn('lit/optional-tool');
        $optional->allows('isDirect')->andReturn(true);

        $core = Mockery::mock(Integration::class);
        $core->allows('id')->andReturn('core');
        $core->allows('isAvailable')->andReturn(true);
        $core->allows('abilities')->andReturn([$optional]);
        $registry = new IntegrationRegistry($core, ...$this->registry()->available());

        $policy = new ExposurePolicy(['lit/optional-tool' => 'indirect', 'lit/rare-tool' => 'direct']);
        $registrar = new ServerRegistrar($registry, $this->instructions(), static fn () => true, null, null, $policy);

        self::assertSame(
            ['lit/guide', 'lit/rare-tool', 'mcp-adapter/discover-abilities', 'mcp-adapter/get-ability-info', 'mcp-adapter/execute-ability'],
            $registrar->serverArguments()['tools']
        );
    }

    public function testGroupSettingsReachTheToolListAndTheInstructions(): void
    {
        $registry = $this->registry();
        $policy = (new ExposurePolicy(['@group:core' => 'disabled', '@readonly:core' => true]))
            ->withGroups($registry->groupMap());
        $instructions = new InstructionsBuilder($registry, null, $policy);

        $args = (new ServerRegistrar($registry, $instructions, static fn () => true, null, null, $policy))
            ->serverArguments();

        // lit/guide is REQUIRED and stays direct; lit/rare-tool is disabled by the group.
        self::assertSame(
            ['lit/guide', 'mcp-adapter/discover-abilities', 'mcp-adapter/get-ability-info', 'mcp-adapter/execute-ability'],
            $args['tools']
        );
        self::assertStringContainsString('Direkt aufrufbare Tools: lit-guide.', $args['description']);
    }

    public function testNoServerWhenOauthIsDisabled(): void
    {
        $registrar = new ServerRegistrar($this->registry(), $this->instructions(), static fn () => false);

        self::assertNull($registrar->serverArguments());
    }

    public function testCreateServerOutsideAdapterInitDoesNothing(): void
    {
        Functions\when('doing_action')->justReturn(false);
        $oauthChecked = false;
        $registrar = new ServerRegistrar(
            $this->registry(),
            $this->instructions(),
            static function () use (&$oauthChecked): bool {
                $oauthChecked = true;
                return true;
            }
        );

        $registrar->createServer();

        self::assertFalse($oauthChecked, 'createServer must bail out before touching the adapter');
    }

    public function testRegisterDisablesAdapterDefaultServerAndHooksCreateServer(): void
    {
        $registrar = new ServerRegistrar($this->registry(), $this->instructions());

        Functions\expect('add_filter')
            ->once()
            ->with('mcp_adapter_create_default_server', '__return_false');
        Functions\expect('add_action')
            ->once()
            ->with('mcp_adapter_init', [$registrar, 'createServer'], 5);

        $registrar->register();
    }

    public function testDefaultOauthEnabledDelegatesToMcpOauthContext(): void
    {
        // LIT\MCP\Server\ServerRegistrar::__construct() defaults to
        // (new \WPMedia\MCP\OAuth\Context())->is_enabled() – exercise that real
        // Context, only stubbing the filter it reads, to prove we track its notion
        // of "enabled" (including the deprecated rocket_mcp_oauth_server_enabled
        // filter Context::is_enabled() also seeds from) instead of duplicating it.
        Filters\expectApplied('wpmedia_mcp_oauth_server_enabled')->once()->andReturn(false);

        $registrar = new ServerRegistrar($this->registry(), $this->instructions());

        self::assertNull($registrar->serverArguments());
    }

    public function testUnhookOAuthDefaultServerRemovesOnlyTheMcpOauthCallback(): void
    {
        $oauthRegistrar = Mockery::mock(OAuthServerRegistrar::class);
        $oauthCallback = [$oauthRegistrar, 'register_server'];
        $unrelatedCallback = static function (): void {
        };

        $hook = new class {
            /** @var array<int, array<string, array{function: mixed, accepted_args: int}>> */
            public array $callbacks = [];
        };
        $hook->callbacks = [
            5 => ['unrelated-id' => ['function' => $unrelatedCallback, 'accepted_args' => 0]],
            10 => ['oauth-id' => ['function' => $oauthCallback, 'accepted_args' => 0]],
        ];
        $GLOBALS['wp_filter']['mcp_adapter_init'] = $hook;

        Functions\expect('remove_action')
            ->once()
            ->with('mcp_adapter_init', $oauthCallback, 10);

        (new ServerRegistrar($this->registry(), $this->instructions()))->unhookOAuthDefaultServer();
    }

    public function testUnhookOAuthDefaultServerIsNoOpWhenHookIsMissing(): void
    {
        unset($GLOBALS['wp_filter']['mcp_adapter_init']);

        Functions\expect('remove_action')->never();

        (new ServerRegistrar($this->registry(), $this->instructions()))->unhookOAuthDefaultServer();
    }

    public function testUnhookOAuthDefaultServerIsNoOpWhenOAuthPackageIsAbsent(): void
    {
        $oauthRegistrar = Mockery::mock(OAuthServerRegistrar::class);
        $oauthCallback = [$oauthRegistrar, 'register_server'];
        $hook = new class {
            /** @var array<int, array<string, array{function: mixed, accepted_args: int}>> */
            public array $callbacks = [];
        };
        $hook->callbacks = [10 => ['oauth-id' => ['function' => $oauthCallback, 'accepted_args' => 0]]];
        $GLOBALS['wp_filter']['mcp_adapter_init'] = $hook;

        Functions\expect('remove_action')->never();

        // Simulate wp-media/mcp-oauth not being installed via the injectable
        // classExists probe (class_exists() is a PHP internal and cannot be
        // stubbed directly through Brain\Monkey/Patchwork).
        $registrar = new ServerRegistrar(
            $this->registry(),
            $this->instructions(),
            null,
            null,
            static fn (): bool => false
        );

        $registrar->unhookOAuthDefaultServer();
    }

    public function testCreateServerUnhooksOAuthDefaultServerBeforeCreatingAdapterServer(): void
    {
        Functions\when('doing_action')->justReturn(true);
        Functions\when('is_wp_error')->justReturn(false);

        $oauthRegistrar = Mockery::mock(OAuthServerRegistrar::class);
        $oauthCallback = [$oauthRegistrar, 'register_server'];
        $hook = new class {
            /** @var array<int, array<string, array{function: mixed, accepted_args: int}>> */
            public array $callbacks = [];
        };
        $hook->callbacks = [10 => ['oauth-id' => ['function' => $oauthCallback, 'accepted_args' => 0]]];
        $GLOBALS['wp_filter']['mcp_adapter_init'] = $hook;

        /** @var list<string> $order */
        $order = [];
        Functions\expect('remove_action')
            ->once()
            ->with('mcp_adapter_init', $oauthCallback, 10)
            ->andReturnUsing(static function () use (&$order): void {
                $order[] = 'unhook';
            });

        $registrar = new ServerRegistrar(
            $this->registry(),
            $this->instructions(),
            static fn (): bool => true,
            static function (array $args) use (&$order): bool {
                $order[] = 'create';
                return true;
            }
        );

        $registrar->createServer();

        self::assertSame(['unhook', 'create'], $order, 'unhook must run before the adapter creates the server');
    }
}