<?php

declare(strict_types=1);

namespace Sogr\Service;

use PDO;
use Sogr\Core\ApiException;
use Sogr\Core\Database;
use Throwable;

/**
 * 7C-A6-R2-R3-R7: kontrolisani oporavak isključivo sync queue zapisa 10.
 * Ne poziva pay niti VOID. MySQL payment 1790 / receipt 00105 ostaju netaknuti.
 */
final class Phase7CA6R2R3R7ControlledSyncRecoveryService
{
    public const PHASE = '7C-A6-R2-R3-R7';
    public const VERSION = '7C-A6-R2-R3-R7.1';
    public const MODE = 'CONTROLLED_SYNC_QUEUE_10_RECOVERY';
    public const QUEUE_ID = 10;
    public const PAYMENT_ID = 1790;
    public const RECEIPT_NUMBER = 105;
    public const HOUSEHOLD_YEAR_ID = 146;
    public const SOURCE_ROW = 147;
    public const REQUEST_ID = 'PHASE7C-A6-R2-R3-baea4902-7e9c-425e-84ed-354ce726c50e';
    public const CONFIRMATION = 'RECOVER_SYNC_QUEUE_10_RECEIPT_00105';

    private PDO $pdo;
    private string $privateRoot;
    private Phase7CSyncService $sync;

    public function __construct(?PDO $pdo = null, ?string $privateRoot = null)
    {
        $this->pdo = $pdo ?? Database::connection();
        if ($privateRoot !== null) {
            $this->privateRoot = rtrim($privateRoot, '/\\');
        } else {
            $dr = isset($_SERVER['DOCUMENT_ROOT']) ? rtrim((string) $_SERVER['DOCUMENT_ROOT'], '/\\') : dirname(__DIR__, 3);
            $this->privateRoot = dirname($dr) . '/sogr_private';
        }
        $this->sync = new Phase7CSyncService($this->pdo, $this->privateRoot);
    }

    /** @return array<string,mixed> */
    public function status(): array
    {
        $snapshot = $this->snapshot();
        $bridge = $this->bridgeInspection($snapshot);
        $gate = $this->gate($snapshot, $bridge);
        return [
            'phase' => self::PHASE,
            'version' => self::VERSION,
            'mode' => self::MODE,
            'valid' => $gate['valid'],
            'writesPerformed' => false,
            'mysqlWrites' => 0,
            'googleSheetsWrites' => 0,
            'target' => $this->targetSummary($snapshot),
            'dateTransport' => $this->dateTransport($snapshot),
            'bridge' => $bridge,
            'gate' => $gate,
            'confirmationRequired' => self::CONFIRMATION,
            'nextStep' => $gate['alreadyRecovered']
                ? 'DOWNLOAD_ALREADY_RECOVERED_RESULT'
                : ($gate['valid'] ? 'CONFIRM_CONTROLLED_QUEUE_10_RECOVERY' : 'STOP_AND_REVIEW_R3_R7_GATE'),
            'checkedAtUtc' => gmdate('c'),
        ];
    }

    /** @return array<string,mixed> */
    public function recover(string $confirmation): array
    {
        if (!hash_equals(self::CONFIRMATION, trim($confirmation))) {
            throw new ApiException('R3_R7_CONFIRMATION_INVALID', 'Potvrda za kontrolisani recovery nije ispravna.', 400);
        }
        $lockName = 'sogr-r3-r7-queue-10';
        $lockStmt = $this->pdo->prepare('SELECT GET_LOCK(:name,5)');
        $lockStmt->execute([':name' => $lockName]);
        if ((int) $lockStmt->fetchColumn() !== 1) {
            throw new ApiException('R3_R7_LOCK_BUSY', 'Druga recovery operacija je već u toku.', 409);
        }

        $before = [];
        $processResult = null;
        try {
            $before = $this->snapshot();
            $beforeBridge = $this->bridgeInspection($before);
            $beforeGate = $this->gate($before, $beforeBridge);
            if (($beforeGate['alreadyRecovered'] ?? false) === true) {
                $result = $this->successResult($before, $beforeBridge, $before, $beforeBridge, [
                    'ok' => true, 'alreadyDone' => true, 'queueId' => self::QUEUE_ID,
                ], true);
                $this->writeEvidence($result);
                return $result;
            }
            if (($beforeGate['valid'] ?? false) !== true) {
                throw new ApiException('R3_R7_GATE_NOT_READY', 'Recovery kapija nije čista; ništa nije pokrenuto.', 409, ['gate' => $beforeGate]);
            }

            $processResult = $this->sync->processQueueId(self::QUEUE_ID);
            $after = $this->snapshot();
            $afterBridge = $this->bridgeInspection($after);
            $afterGate = $this->gate($after, $afterBridge);

            $success = $this->isRecovered($after, $afterBridge);
            $result = $success
                ? $this->successResult($before, $beforeBridge, $after, $afterBridge, $processResult, false)
                : $this->failureResult($before, $beforeBridge, $after, $afterBridge, $processResult);
            $this->writeEvidence($result);
            return $result;
        } finally {
            try {
                $release = $this->pdo->prepare('SELECT RELEASE_LOCK(:name)');
                $release->execute([':name' => $lockName]);
            } catch (Throwable) {
            }
        }
    }

    /** @return array<string,mixed> */
    private function snapshot(): array
    {
        $paymentStmt = $this->pdo->prepare(
            "SELECT p.id,p.request_id,p.receipt_number,p.payment_date,p.membership_total,p.donation_total,
                    p.payment_status,p.row_version,r.id AS receipt_id,r.receipt_status,r.receipt_sheet_year,
                    r.receipt_sheet_row,r.receipt_link,r.row_version AS receipt_row_version
             FROM payments p JOIN receipts r ON r.payment_id=p.id
             WHERE p.id=:payment AND p.receipt_number=:receipt LIMIT 1"
        );
        $paymentStmt->execute([':payment' => self::PAYMENT_ID, ':receipt' => self::RECEIPT_NUMBER]);
        $payment = $paymentStmt->fetch(PDO::FETCH_ASSOC) ?: null;

        $queueStmt = $this->pdo->prepare(
            "SELECT id,direction,entity_type,entity_id,operation_name,dedupe_key,payload_json,queue_status,
                    priority,attempts,next_attempt_at,locked_at,locked_by,last_error,completed_at,created_at,updated_at
             FROM sync_queue WHERE id=:id LIMIT 1"
        );
        $queueStmt->execute([':id' => self::QUEUE_ID]);
        $queue = $queueStmt->fetch(PDO::FETCH_ASSOC) ?: null;
        if (is_array($queue)) {
            $queue['payload'] = $this->decode((string) ($queue['payload_json'] ?? ''));
            unset($queue['payload_json']);
        }

        $hyStmt = $this->pdo->prepare(
            "SELECT hy.id,hy.year,hy.first_name,hy.last_name,hy.sheet_row,hy.row_version,
                    apl.payment_item_id,pi.payment_id,pi.item_status
             FROM household_years hy
             LEFT JOIN active_payment_links apl ON apl.household_year_id=hy.id
             LEFT JOIN payment_items pi ON pi.id=apl.payment_item_id
             WHERE hy.id=:id LIMIT 1"
        );
        $hyStmt->execute([':id' => self::HOUSEHOLD_YEAR_ID]);
        $householdYear = $hyStmt->fetch(PDO::FETCH_ASSOC) ?: null;

        $sequence = (int) $this->pdo->query("SELECT current_value FROM number_sequences WHERE sequence_name='receipt'")->fetchColumn();
        $problemCount = (int) $this->pdo->query(
            "SELECT COUNT(*) FROM sync_queue WHERE direction='DB_TO_SHEETS' AND queue_status IN ('PENDING','PROCESSING','FAILED','CONFLICT')"
        )->fetchColumn();
        $duplicate = (int) $this->pdo->query(
            "SELECT COUNT(*) FROM payments WHERE receipt_number=105 AND payment_status='ACTIVE'"
        )->fetchColumn();
        $receiptLinkStmt = $this->pdo->prepare(
            "SELECT srl.id,srl.sheet_row,srl.last_source,srl.last_synced_at
             FROM sheet_row_links srl WHERE srl.entity_type='RECEIPT' AND srl.entity_id=:id ORDER BY srl.id DESC"
        );
        $receiptLinkStmt->execute([':id' => is_array($payment) ? (int) ($payment['receipt_id'] ?? 0) : 0]);
        $receiptLinks = $receiptLinkStmt->fetchAll(PDO::FETCH_ASSOC);
        $idempotencyStmt = $this->pdo->prepare(
            'SELECT request_status,response_json FROM idempotency_requests WHERE request_id=:request LIMIT 1'
        );
        $idempotencyStmt->execute([':request' => self::REQUEST_ID]);
        $idempotency = $idempotencyStmt->fetch(PDO::FETCH_ASSOC) ?: null;
        if (is_array($idempotency)) {
            $idempotency['response'] = $this->decode((string) ($idempotency['response_json'] ?? ''));
            unset($idempotency['response_json']);
        }
        return [
            'payment' => $payment,
            'queue' => $queue,
            'householdYear' => $householdYear,
            'sequence' => $sequence,
            'problemQueueCount' => $problemCount,
            'activeReceipt105Count' => $duplicate,
            'receiptSheetLinks' => $receiptLinks,
            'idempotency' => $idempotency,
            'fingerprint' => hash('sha256', self::json([$payment,$queue,$householdYear,$sequence,$problemCount,$duplicate,$receiptLinks,$idempotency])),
        ];
    }

    /** @param array<string,mixed> $snapshot @return array<string,mixed> */
    private function bridgeInspection(array $snapshot): array
    {
        $health = $this->sync->bridgeHealth();
        $job = $this->job($snapshot);
        $normalized = Phase7CSyncService::normalizeJobForBridge($job);
        $preflight = $this->sync->preflightJob($job);
        return [
            'health' => $health,
            'preflight' => $preflight,
            'originalDate' => (string) ($job['payload']['datum'] ?? ''),
            'normalizedDate' => (string) ($normalized['payload']['datum'] ?? ''),
            'normalizationApplied' => (string) ($job['payload']['datum'] ?? '') !== (string) ($normalized['payload']['datum'] ?? ''),
        ];
    }

    /** @param array<string,mixed> $snapshot @return array<string,mixed> */
    private function job(array $snapshot): array
    {
        $job = $snapshot['queue']['payload']['job'] ?? null;
        if (!is_array($job)) {
            throw new ApiException('R3_R7_JOB_MISSING', 'Queue 10 nema ispravan job payload.', 500);
        }
        return $job;
    }

    /** @param array<string,mixed> $s @param array<string,mixed> $b @return array<string,mixed> */
    private function gate(array $s, array $b): array
    {
        $p = $s['payment'] ?? null;
        $q = $s['queue'] ?? null;
        $hy = $s['householdYear'] ?? null;
        $pf = $b['preflight'] ?? [];
        $already = $this->isRecovered($s, $b);
        $checks = [
            'paymentExact' => is_array($p) && (int) ($p['id'] ?? 0) === self::PAYMENT_ID
                && (string) ($p['request_id'] ?? '') === self::REQUEST_ID
                && (int) ($p['receipt_number'] ?? 0) === self::RECEIPT_NUMBER
                && (string) ($p['payment_status'] ?? '') === 'ACTIVE'
                && (string) ($p['receipt_status'] ?? '') === 'ACTIVE',
            'amountExact' => is_array($p) && (float) ($p['membership_total'] ?? -1) === 25.0
                && (float) ($p['donation_total'] ?? -1) === 0.0,
            'householdYearLinked' => is_array($hy) && (int) ($hy['id'] ?? 0) === self::HOUSEHOLD_YEAR_ID
                && (int) ($hy['sheet_row'] ?? 0) === self::SOURCE_ROW
                && (int) ($hy['payment_id'] ?? 0) === self::PAYMENT_ID
                && (string) ($hy['item_status'] ?? '') === 'ACTIVE',
            'sequence105' => (int) ($s['sequence'] ?? 0) === self::RECEIPT_NUMBER,
            'oneActiveReceipt105' => (int) ($s['activeReceipt105Count'] ?? 0) === 1,
            'idempotencyDone' => (string) ($s['idempotency']['request_status'] ?? '') === 'DONE',
            'queueExact' => is_array($q) && (int) ($q['id'] ?? 0) === self::QUEUE_ID
                && (string) ($q['direction'] ?? '') === 'DB_TO_SHEETS'
                && (string) ($q['entity_type'] ?? '') === 'PAYMENT'
                && (int) ($q['entity_id'] ?? 0) === self::PAYMENT_ID,
            'queueStatusRecoverable' => is_array($q) && in_array((string) ($q['queue_status'] ?? ''), ['FAILED','PENDING','DONE'], true),
            'onlyTargetProblemQueue' => $already || (int) ($s['problemQueueCount'] ?? 0) === 1,
            'bridgeHealthy' => ($b['health']['ok'] ?? false) === true && ($b['health']['ready'] ?? false) === true,
            'dateNormalized' => ($b['normalizationApplied'] ?? false) === true
                && (string) ($b['originalDate'] ?? '') === '2026-07-24'
                && (string) ($b['normalizedDate'] ?? '') === '24.07.2026.',
            'bridgePreflightReady' => ($pf['ok'] ?? false) === true && (($pf['ready'] ?? false) === true || ($pf['alreadySynced'] ?? false) === true),
        ];
        return [
            'valid' => !in_array(false, $checks, true),
            'alreadyRecovered' => $already,
            'checks' => $checks,
        ];
    }

    /** @param array<string,mixed> $s @param array<string,mixed> $b */
    private function isRecovered(array $s, array $b): bool
    {
        $p = $s['payment'] ?? [];
        $q = $s['queue'] ?? [];
        $pf = $b['preflight'] ?? [];
        return (string) ($q['queue_status'] ?? '') === 'DONE'
            && (int) ($p['receipt_sheet_row'] ?? 0) > 0
            && count($s['receiptSheetLinks'] ?? []) === 1
            && (int) ($b['health']['maxReceiptNumber'] ?? 0) >= self::RECEIPT_NUMBER
            && (($pf['alreadySynced'] ?? false) === true || is_array($pf['existingReceipt'] ?? null))
            && (int) ($s['problemQueueCount'] ?? -1) === 0;
    }

    /** @param array<string,mixed> $s */
    private function targetSummary(array $s): array
    {
        $p = $s['payment'] ?? [];
        $q = $s['queue'] ?? [];
        return [
            'queueId' => self::QUEUE_ID,
            'paymentId' => self::PAYMENT_ID,
            'receiptNumber' => '00105',
            'requestId' => self::REQUEST_ID,
            'payer' => 'Ilver Džaferi',
            'sourceRow' => self::SOURCE_ROW,
            'paymentStatus' => $p['payment_status'] ?? null,
            'receiptStatus' => $p['receipt_status'] ?? null,
            'queueStatus' => $q['queue_status'] ?? null,
            'attempts' => isset($q['attempts']) ? (int) $q['attempts'] : null,
            'lastError' => $q['last_error'] ?? null,
            'receiptSheetRow' => isset($p['receipt_sheet_row']) ? (int) $p['receipt_sheet_row'] : null,
        ];
    }

    /** @param array<string,mixed> $s */
    private function dateTransport(array $s): array
    {
        $job = $this->job($s);
        $normalized = Phase7CSyncService::normalizeJobForBridge($job);
        return [
            'mysqlDate' => (string) ($s['payment']['payment_date'] ?? ''),
            'queueOriginalDate' => (string) ($job['payload']['datum'] ?? ''),
            'bridgeTransportDate' => (string) ($normalized['payload']['datum'] ?? ''),
            'mysqlDateChanged' => false,
        ];
    }

    /** @return array<string,mixed> */
    private function successResult(array $before, array $beforeBridge, array $after, array $afterBridge, array $process, bool $already): array
    {
        return [
            'phase' => self::PHASE,
            'version' => self::VERSION,
            'mode' => self::MODE,
            'valid' => true,
            'recoveryCompleted' => true,
            'alreadyRecovered' => $already,
            'paymentCommitRepeated' => false,
            'voidCalled' => false,
            'targetQueueProcessed' => !$already,
            'mysqlFinancialValuesChanged' => false,
            'mysqlRecoveryMetadataWritten' => !$already,
            'googleSheetsWrites' => (!$already && (int) ($beforeBridge['health']['maxReceiptNumber'] ?? 0) < 105) ? 1 : 0,
            'processResult' => $process,
            'before' => ['target'=>$this->targetSummary($before),'bridge'=>$beforeBridge,'fingerprint'=>$before['fingerprint']],
            'after' => ['target'=>$this->targetSummary($after),'bridge'=>$afterBridge,'fingerprint'=>$after['fingerprint']],
            'checks' => [
                'queueDone' => (string) ($after['queue']['queue_status'] ?? '') === 'DONE',
                'sheetsReceipt105Present' => (int) ($afterBridge['health']['maxReceiptNumber'] ?? 0) >= 105,
                'receiptSheetRowStored' => (int) ($after['payment']['receipt_sheet_row'] ?? 0) > 0,
                'receiptSheetLinkPresent' => count($after['receiptSheetLinks'] ?? []) === 1,
                'noProblemQueues' => (int) ($after['problemQueueCount'] ?? -1) === 0,
                'paymentStillActive' => (string) ($after['payment']['payment_status'] ?? '') === 'ACTIVE',
                'receiptStillActive' => (string) ($after['payment']['receipt_status'] ?? '') === 'ACTIVE',
                'sequenceStill105' => (int) ($after['sequence'] ?? 0) === 105,
            ],
            'message' => 'USPEŠNO: queue 10 je sinhronizovan. Priznanica 00105 postoji u MySQL-u i Google Sheets-u.',
            'readyForNextPhase' => true,
            'nextStep' => 'READY_FOR_7C_A6_R2_R4_RECEIPT_PDF_PRINT_AND_NORMAL_APP_VALIDATION',
            'checkedAtUtc' => gmdate('c'),
        ];
    }

    /** @return array<string,mixed> */
    private function failureResult(array $before, array $beforeBridge, array $after, array $afterBridge, ?array $process): array
    {
        return [
            'phase' => self::PHASE,
            'version' => self::VERSION,
            'mode' => self::MODE,
            'valid' => false,
            'recoveryCompleted' => false,
            'paymentCommitRepeated' => false,
            'voidCalled' => false,
            'processResult' => $process,
            'before' => ['target'=>$this->targetSummary($before),'bridge'=>$beforeBridge,'fingerprint'=>$before['fingerprint']],
            'after' => ['target'=>$this->targetSummary($after),'bridge'=>$afterBridge,'fingerprint'=>$after['fingerprint']],
            'message' => 'Recovery nije potpuno potvrđen. Ne ponavljajte COMMIT i ne koristite VOID.',
            'readyForNextPhase' => false,
            'nextStep' => 'STOP_AND_SEND_R3_R7_RESULT',
            'checkedAtUtc' => gmdate('c'),
        ];
    }

    /** @param array<string,mixed> $result */
    private function writeEvidence(array $result): void
    {
        $dir = $this->privateRoot . '/backups/phase7c-a6-r2-r3-r7';
        if (!is_dir($dir) && !mkdir($dir, 0700, true) && !is_dir($dir)) return;
        @chmod($dir, 0700);
        $path = $dir . '/recovery-' . gmdate('Ymd-His') . '-' . substr(hash('sha256', self::json($result)), 0, 12) . '.json';
        @file_put_contents($path, self::json($result), LOCK_EX);
        @chmod($path, 0600);
    }

    /** @return array<string,mixed> */
    private function decode(string $value): array
    {
        if (trim($value) === '') return [];
        try { $d = json_decode($value, true, 512, JSON_THROW_ON_ERROR); return is_array($d) ? $d : []; }
        catch (Throwable) { return []; }
    }

    private static function json(mixed $value): string
    {
        return json_encode($value, JSON_UNESCAPED_UNICODE|JSON_UNESCAPED_SLASHES|JSON_THROW_ON_ERROR);
    }
}