<?php

declare(strict_types=1);

namespace KTXT\ProviderImap\Tests\Unit;

use Generator;
use KTXC\Db\Collection;
use KTXC\Db\DataStore;
use KTXF\Resource\Filter\IFilter;
use KTXF\Resource\Sort\ISort;
use KTXM\ProviderImap\Client\Mailbox;
use KTXM\ProviderImap\Providers\CollectionResource;
use KTXM\ProviderImap\Providers\LiveService;
use KTXM\ProviderImap\Service\Cache\HarmonizationService;
use KTXM\ProviderImap\Service\Cache\MessageIngestor;
use KTXM\ProviderImap\Service\Live\LiveMailService;
use KTXM\ProviderImap\Stores\MailboxStore;
use KTXM\ProviderImap\Stores\MessageFileStore;
use KTXM\ProviderImap\Stores\MessageStore;
use LogicException;
use MongoDB\UpdateResult;
use PHPUnit\Framework\TestCase;

final class HarmonizationServiceTest extends TestCase
{
    private array $calls = [];

    public function testMailboxesAreAddedUpdatedAndRemoved(): void
    {
        $service = $this->harmonizer(
            cached: ['INBOX' => [], 'Old' => []],
            remote: ['INBOX', 'Reports'],
        );

        $result = $service->harmonizeMailboxes();

        $this->assertSame(['added' => ['Reports'], 'updated' => ['INBOX'], 'removed' => ['Old']], $result);
        $this->assertSame([
            ['upsert', 'tenant', 'svc', 'INBOX'],
            ['upsert', 'tenant', 'svc', 'Reports'],
            ['messages.deleteByMailbox', 'svc', 'Old'],
            ['files.deleteByMailbox', 'tenant', 'svc', 'Old'],
            ['mailboxes.delete', 'svc', 'Old'],
        ], $this->calls);
    }

    public function testNothingIsPurgedWhenTheServerListHasNoInbox(): void
    {
        $service = $this->harmonizer(
            cached: ['INBOX' => [], 'Reports' => []],
            remote: [],
        );

        $result = $service->harmonizeMailboxes();

        $this->assertSame(['added' => [], 'updated' => [], 'removed' => []], $result);
        $this->assertSame([], $this->calls);
    }

    public function testUnboundServiceIsRejected(): void
    {
        $unbound = new HarmonizationService(
            $this->createStub(MailboxStore::class),
            $this->createStub(MessageStore::class),
            $this->createStub(MessageFileStore::class),
            $this->createStub(MessageIngestor::class),
        );

        $this->expectException(LogicException::class);
        $unbound->harmonizeMailboxes();
    }

    public function testLockIsTakenOnlyWhenFreeExpiredOrOwned(): void
    {
        $collection = $this->createMock(Collection::class);
        $collection->expects($this->exactly(2))
            ->method('updateOne')
            ->willReturnCallback(function (array $filter, array $update) use (&$matched): UpdateResult {
                $this->assertSame(['lock' => null], $filter['$or'][0]);
                $this->assertArrayHasKey('$lte', $filter['$or'][1]['lock.expiresAt']);
                $this->assertSame(['lock.owner' => 'run-1'], $filter['$or'][2]);
                $this->assertSame('run-1', $update['$set']['lock']['owner']);
                $result = $this->createStub(UpdateResult::class);
                $result->method('getMatchedCount')->willReturn(array_shift($matched));
                return $result;
            });
        $matched = [1, 0];

        $store = new MailboxStore($this->dataStore($collection));

        $this->assertTrue($store->acquireLock('svc', 'INBOX', 'run-1', 300));
        $this->assertFalse($store->acquireLock('svc', 'INBOX', 'run-1', 300));
    }

    public function testStateFillsDefaultsAndIgnoresOtherFields(): void
    {
        $collection = $this->createStub(Collection::class);
        $collection->method('findOne')->willReturn([
            'sid' => 'svc', 'name' => 'INBOX', 'uidValidity' => 7, 'lock' => ['owner' => 'x'],
        ]);

        $state = (new MailboxStore($this->dataStore($collection)))->state('svc', 'INBOX');

        $this->assertSame([...MailboxStore::STATE_DEFAULTS, 'uidValidity' => 7], $state);
    }

    public function testNewMailboxStartsWithDefaultState(): void
    {
        $collection = $this->createMock(Collection::class);
        $collection->expects($this->once())
            ->method('updateOne')
            ->with(
                $this->anything(),
                $this->callback(fn (array $update): bool => $update['$setOnInsert'] === MailboxStore::STATE_DEFAULTS
                    && array_intersect_key($update['$set'], MailboxStore::STATE_DEFAULTS) === []),
                ['upsert' => true],
            );

        $mailbox = (new CollectionResource('imap', 'svc'))->fromImap(new Mailbox('INBOX', '/', []));
        (new MailboxStore($this->dataStore($collection)))->upsert('tenant', 'svc', $mailbox);
    }

    /**
     * @param array<string, array> $cached
     * @param string[] $remote
     */
    private function harmonizer(array $cached, array $remote): HarmonizationService
    {
        $mailboxes = $this->createStub(MailboxStore::class);
        $mailboxes->method('list')->willReturn($cached);
        $mailboxes->method('upsert')->willReturnCallback(function (string $tid, string $sid, $collection): void {
            $this->calls[] = ['upsert', $tid, $sid, $collection->identifier()];
        });
        $mailboxes->method('delete')->willReturnCallback(function (string $sid, string $name): void {
            $this->calls[] = ['mailboxes.delete', $sid, $name];
        });

        $messages = $this->createStub(MessageStore::class);
        $messages->method('deleteByMailbox')->willReturnCallback(function (string $sid, string $name): void {
            $this->calls[] = ['messages.deleteByMailbox', $sid, $name];
        });

        $files = $this->createStub(MessageFileStore::class);
        $files->method('deleteByMailbox')->willReturnCallback(function (string $tid, string $sid, string $name): void {
            $this->calls[] = ['files.deleteByMailbox', $tid, $sid, $name];
        });

        $service = (new LiveService())->fromStore(['tid' => 'tenant', 'sid' => 'svc']);
        $live = new HarmonizationServiceTestLiveStub($service);
        $live->mailboxes = array_map(static fn (string $name): Mailbox => new Mailbox($name, '/', []), $remote);

        return (new HarmonizationService($mailboxes, $messages, $files, $this->createStub(MessageIngestor::class)))->for($service, $live);
    }

    private function dataStore(Collection $collection): DataStore
    {
        $dataStore = $this->createStub(DataStore::class);
        $dataStore->method('selectCollection')->willReturn($collection);
        return $dataStore;
    }
}

final class HarmonizationServiceTestLiveStub extends LiveMailService
{
    /** @var Mailbox[] */
    public array $mailboxes = [];

    public function collectionList(?string $location = null, ?IFilter $filter = null, ?ISort $sort = null): array
    {
        $list = [];
        foreach ($this->mailboxes as $mailbox) {
            $list[$mailbox->name()] = (new CollectionResource('imap', 'svc'))->fromImap($mailbox);
        }
        return $list;
    }
}