<?php
declare(strict_types=1);

namespace Modules\Boersenchecker\Support;

use PDO;
use RuntimeException;

final class DashboardPage
{
    private PDO $pdo;
    private array $user;
    private bool $isAdmin;
    private string $ownerSub;
    private array $moduleSettings;
    private string $defaultReportCurrency;
    private float $fxMaxAgeHours;
    private int $marketDataMinIntervalMinutes;
    private int $editPortfolioId;
    private int $editPositionId;
    private string $portfolioTable;
    private string $instrumentTable;
    private string $positionTable;
    private string $quoteTable;
    private InstrumentRegistry $instrumentRegistry;
    private string $symbolSearchKeywords = '';
    private array $symbolSearchResults = [];
    private array $availableOwners = [];

    public function __construct()
    {
        $this->pdo = \module_fn('boersenchecker', 'pdo');
        \module_fn('boersenchecker', 'ensure_schema');

        $this->user = \auth_user() ?? [];
        $this->isAdmin = \auth_is_admin();
        $this->ownerSub = trim((string) ($this->user['sub'] ?? 'local'));
        $this->availableOwners = $this->buildAvailableOwners();
        if ($this->isAdmin) {
            $requestedOwner = trim((string) ($_GET['owner_sub'] ?? $_POST['owner_sub'] ?? ''));
            if ($requestedOwner !== '' && isset($this->availableOwners[$requestedOwner])) {
                $this->ownerSub = $requestedOwner;
            }
        }
        $this->moduleSettings = \modules()->settings('boersenchecker');
        $this->defaultReportCurrency = $this->normalizeCurrency((string) ($this->moduleSettings['report_currency'] ?? 'EUR'));
        $this->fxMaxAgeHours = (float) ($this->moduleSettings['fx_max_age_hours'] ?? 6);
        if ($this->fxMaxAgeHours <= 0) {
            $this->fxMaxAgeHours = 6.0;
        }

        $this->marketDataMinIntervalMinutes = (int) (($this->moduleSettings['alpha_vantage_min_interval_minutes'] ?? null) ?: 60);
        if ($this->marketDataMinIntervalMinutes <= 0) {
            $this->marketDataMinIntervalMinutes = 60;
        }

        $this->editPortfolioId = (int) ($_GET['edit_portfolio'] ?? 0);
        $this->editPositionId = (int) ($_GET['edit_position'] ?? 0);

        $table = static fn (string $name): string => \module_fn('boersenchecker', 'table', $name);
        $this->portfolioTable = $table('portfolios');
        $this->instrumentTable = $table('instruments');
        $this->positionTable = $table('positions');
        $this->quoteTable = $table('quotes');
        $this->instrumentRegistry = new InstrumentRegistry(
            $this->pdo,
            $this->instrumentTable,
            $this->positionTable,
            $this->quoteTable,
        );
    }

    public function handle(): array
    {
        $notice = null;
        $error = null;

        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            try {
                $notice = $this->handlePost();
            } catch (\Throwable $e) {
                $error = $e->getMessage();
            }
        }

        $state = $this->loadState();

        if ($notice === null && isset($state['notice_override']) && is_string($state['notice_override'])) {
            $notice = $state['notice_override'];
        }
        if ($error === null && isset($state['error_override']) && is_string($state['error_override'])) {
            $error = $state['error_override'];
        }

        return [
            'notice' => $notice,
            'error' => $error,
            'isAdmin' => $this->isAdmin,
            'ownerSub' => $this->ownerSub,
            'availableOwners' => array_values($this->availableOwners),
            'defaultReportCurrency' => $this->defaultReportCurrency,
            'fxMaxAgeHours' => $this->fxMaxAgeHours,
            'marketDataMinIntervalMinutes' => $this->marketDataMinIntervalMinutes,
            'symbolSearchKeywords' => $this->symbolSearchKeywords,
            'symbolSearchResults' => $this->symbolSearchResults,
            'editPortfolio' => $state['editPortfolio'],
            'editPosition' => $state['editPosition'],
            'portfolios' => $state['portfolios'],
            'portfolioById' => $state['portfolioById'],
            'portfolioStats' => $state['portfolioStats'],
            'positions' => $state['positions'],
            'instrumentList' => $state['instrumentList'],
            'quoteHistory' => $state['quoteHistory'],
            'selectedInstrumentForQuote' => $state['selectedInstrumentForQuote'],
            'selectedInstrumentQuoteCurrency' => $state['selectedInstrumentQuoteCurrency'],
            'fmtNumber' => fn (?float $value, int $scale = 2): string => $this->formatNumber($value, $scale),
            'fmtDateTime' => fn (?string $value, ?string $source = null): string => (string) \module_fn('boersenchecker', 'format_datetime_for_display', $value, $source),
            'localNowInputValue' => (string) \module_fn('boersenchecker', 'local_now_input_value'),
        ];
    }

    private function handlePost(): string
    {
        $action = trim((string) ($_POST['action'] ?? ''));

        return match ($action) {
            'save_portfolio' => $this->savePortfolio(),
            'delete_portfolio' => $this->deletePortfolio(),
            'save_position' => $this->savePosition(),
            'delete_position' => $this->deletePosition(),
            'save_quote' => $this->saveQuote(),
            'refresh_market_data_position' => $this->refreshMarketDataPosition(),
            'refresh_market_data_all' => $this->refreshMarketDataAll(),
            'search_symbol' => $this->searchSymbol(),
            'delete_quote' => $this->deleteQuote(),
            'refresh_fx' => $this->refreshFx(),
            default => '',
        };
    }

    private function loadState(): array
    {
        $portfolios = $this->fetchPortfolios();
        $positions = $this->fetchPositions();
        $instrumentList = $this->buildInstrumentList($positions);
        [$quoteHistory, $latestQuotes] = $this->fetchQuotes(array_keys($instrumentList));
        $portfolioById = $this->buildPortfolioById($portfolios);
        [$positions, $portfolioStats] = $this->enrichPositions($positions, $portfolioById, $latestQuotes);

        $editPortfolio = null;
        if ($this->editPortfolioId > 0 && isset($portfolioById[$this->editPortfolioId])) {
            $editPortfolio = $portfolioById[$this->editPortfolioId];
        }

        $editPosition = null;
        if ($this->editPositionId > 0) {
            foreach ($positions as $position) {
                if ((int) $position['id'] === $this->editPositionId) {
                    $editPosition = $position;
                    break;
                }
            }
        }

        $selectedInstrumentForQuote = $editPosition
            ? (int) $editPosition['instrument_id']
            : (int) ($_GET['instrument_id'] ?? 0);
        $selectedInstrumentQuoteCurrency = $this->defaultReportCurrency;
        if ($selectedInstrumentForQuote > 0 && isset($instrumentList[$selectedInstrumentForQuote])) {
            $selectedInstrumentQuoteCurrency = $this->normalizeCurrency(
                (string) ($instrumentList[$selectedInstrumentForQuote]['quote_currency'] ?? $this->defaultReportCurrency)
            );
        }

        $candidateName = trim((string) ($_GET['instrument_name_candidate'] ?? ''));
        $candidateSymbol = trim((string) ($_GET['symbol_candidate'] ?? ''));
        $candidateIsin = trim((string) ($_GET['isin_candidate'] ?? ''));
        $candidateMarket = trim((string) ($_GET['market_candidate'] ?? ''));
        $candidateCurrency = $this->normalizeCurrency((string) ($_GET['quote_currency_candidate'] ?? $this->defaultReportCurrency));

        if ($editPosition === null) {
            $editPosition = [
                'instrument_name' => $candidateName,
                'symbol' => $candidateSymbol,
                'isin' => $candidateIsin,
                'market' => $candidateMarket,
                'quote_currency' => $candidateCurrency,
                'purchase_currency' => $this->defaultReportCurrency,
                'purchase_date' => date('Y-m-d'),
            ];
        } else {
            if ($candidateName !== '') {
                $editPosition['instrument_name'] = $candidateName;
            }
            if ($candidateSymbol !== '') {
                $editPosition['symbol'] = $candidateSymbol;
            }
            if ($candidateIsin !== '') {
                $editPosition['isin'] = $candidateIsin;
            }
            if ($candidateMarket !== '') {
                $editPosition['market'] = $candidateMarket;
            }
            if ($candidateCurrency !== '') {
                $editPosition['quote_currency'] = $candidateCurrency;
            }
        }

        return [
            'portfolios' => $portfolios,
            'portfolioById' => $portfolioById,
            'portfolioStats' => $portfolioStats,
            'positions' => $positions,
            'instrumentList' => $instrumentList,
            'quoteHistory' => $quoteHistory,
            'editPortfolio' => $editPortfolio,
            'editPosition' => $editPosition,
            'selectedInstrumentForQuote' => $selectedInstrumentForQuote,
            'selectedInstrumentQuoteCurrency' => $selectedInstrumentQuoteCurrency,
        ];
    }

    private function savePortfolio(): string
    {
        $portfolioId = (int) ($_POST['portfolio_id'] ?? 0);
        $name = trim((string) ($_POST['portfolio_name'] ?? ''));
        $baseCurrency = $this->normalizeCurrency((string) ($_POST['portfolio_base_currency'] ?? $this->defaultReportCurrency));
        $notes = trim((string) ($_POST['portfolio_notes'] ?? ''));

        if ($name === '') {
            throw new RuntimeException('Bitte einen Depotnamen angeben.');
        }

        if ($portfolioId > 0) {
            $stmt = $this->pdo->prepare(
                'UPDATE ' . $this->portfolioTable . '
                 SET name = :name, base_currency = :base_currency, notes = :notes, updated_at = CURRENT_TIMESTAMP
                 WHERE id = :id AND owner_sub = :owner_sub'
            );
            $stmt->execute([
                'id' => $portfolioId,
                'owner_sub' => $this->ownerSub,
                'name' => $name,
                'base_currency' => $baseCurrency,
                'notes' => $notes !== '' ? $notes : null,
            ]);
            return 'Depot aktualisiert.';
        }

        $stmt = $this->pdo->prepare(
            'INSERT INTO ' . $this->portfolioTable . ' (owner_sub, name, base_currency, notes)
             VALUES (:owner_sub, :name, :base_currency, :notes)'
        );
        $stmt->execute([
            'owner_sub' => $this->ownerSub,
            'name' => $name,
            'base_currency' => $baseCurrency,
            'notes' => $notes !== '' ? $notes : null,
        ]);
        return 'Depot angelegt.';
    }

    private function deletePortfolio(): string
    {
        $portfolioId = (int) ($_POST['portfolio_id'] ?? 0);
        $countStmt = $this->pdo->prepare('SELECT COUNT(*) FROM ' . $this->positionTable . ' WHERE portfolio_id = :portfolio_id AND owner_sub = :owner_sub');
        $countStmt->execute([
            'portfolio_id' => $portfolioId,
            'owner_sub' => $this->ownerSub,
        ]);
        if ((int) $countStmt->fetchColumn() > 0) {
            throw new RuntimeException('Depot kann erst geloescht werden, wenn alle Positionen entfernt wurden.');
        }

        $stmt = $this->pdo->prepare('DELETE FROM ' . $this->portfolioTable . ' WHERE id = :id AND owner_sub = :owner_sub');
        $stmt->execute([
            'id' => $portfolioId,
            'owner_sub' => $this->ownerSub,
        ]);
        return 'Depot geloescht.';
    }

    private function savePosition(): string
    {
        $positionId = (int) ($_POST['position_id'] ?? 0);
        $portfolioId = (int) ($_POST['portfolio_id'] ?? 0);
        $quantity = (float) ($_POST['quantity'] ?? 0);
        $purchasePrice = (float) ($_POST['purchase_price'] ?? 0);
        $purchaseCurrency = $this->normalizeCurrency((string) ($_POST['purchase_currency'] ?? $this->defaultReportCurrency));
        $purchaseDate = trim((string) ($_POST['purchase_date'] ?? ''));
        $fees = trim((string) ($_POST['fees'] ?? ''));
        $notes = trim((string) ($_POST['position_notes'] ?? ''));

        if ($portfolioId <= 0) {
            throw new RuntimeException('Bitte zuerst ein Depot auswaehlen.');
        }
        if ($quantity <= 0 || $purchasePrice <= 0 || $purchaseDate === '') {
            throw new RuntimeException('Bitte Stueckzahl, Kaufpreis und Kaufdatum angeben.');
        }

        $portfolioOwnerStmt = $this->pdo->prepare('SELECT id FROM ' . $this->portfolioTable . ' WHERE id = :id AND owner_sub = :owner_sub LIMIT 1');
        $portfolioOwnerStmt->execute([
            'id' => $portfolioId,
            'owner_sub' => $this->ownerSub,
        ]);
        if ($portfolioOwnerStmt->fetchColumn() === false) {
            throw new RuntimeException('Das ausgewaehlte Depot ist nicht verfuegbar.');
        }

        $instrumentId = $this->upsertInstrument([
            'id' => (int) ($_POST['instrument_id'] ?? 0),
            'isin' => $_POST['isin'] ?? '',
            'wkn' => $_POST['wkn'] ?? '',
            'symbol' => $_POST['symbol'] ?? '',
            'name' => $_POST['instrument_name'] ?? '',
            'quote_currency' => $_POST['quote_currency'] ?? $purchaseCurrency,
            'market' => $_POST['market'] ?? '',
        ]);

        $payload = [
            'owner_sub' => $this->ownerSub,
            'portfolio_id' => $portfolioId,
            'instrument_id' => $instrumentId,
            'quantity' => $quantity,
            'purchase_price' => $purchasePrice,
            'purchase_currency' => $purchaseCurrency,
            'purchase_date' => $purchaseDate,
            'fees' => $fees !== '' ? (float) $fees : null,
            'notes' => $notes !== '' ? $notes : null,
        ];

        if ($positionId > 0) {
            $stmt = $this->pdo->prepare(
                'UPDATE ' . $this->positionTable . '
                 SET portfolio_id = :portfolio_id,
                     instrument_id = :instrument_id,
                     quantity = :quantity,
                     purchase_price = :purchase_price,
                     purchase_currency = :purchase_currency,
                     purchase_date = :purchase_date,
                     fees = :fees,
                     notes = :notes,
                     updated_at = CURRENT_TIMESTAMP
                 WHERE id = :id AND owner_sub = :owner_sub'
            );
            $stmt->execute($payload + ['id' => $positionId]);
            return 'Position aktualisiert.';
        }

        $stmt = $this->pdo->prepare(
            'INSERT INTO ' . $this->positionTable . ' (
                owner_sub, portfolio_id, instrument_id, quantity, purchase_price, purchase_currency, purchase_date, fees, notes
             ) VALUES (
                :owner_sub, :portfolio_id, :instrument_id, :quantity, :purchase_price, :purchase_currency, :purchase_date, :fees, :notes
             )'
        );
        $stmt->execute($payload);
        return 'Position gespeichert.';
    }

    private function deletePosition(): string
    {
        $positionId = (int) ($_POST['position_id'] ?? 0);
        $stmt = $this->pdo->prepare('DELETE FROM ' . $this->positionTable . ' WHERE id = :id AND owner_sub = :owner_sub');
        $stmt->execute([
            'id' => $positionId,
            'owner_sub' => $this->ownerSub,
        ]);
        return 'Position geloescht.';
    }

    private function saveQuote(): string
    {
        $instrumentId = (int) ($_POST['quote_instrument_id'] ?? 0);
        $price = (float) ($_POST['quote_price'] ?? 0);
        $currency = $this->normalizeCurrency((string) ($_POST['quote_currency'] ?? $this->defaultReportCurrency));
        $quotedAt = $this->normalizeDateTimeLocal((string) ($_POST['quoted_at'] ?? ''));
        $source = trim((string) ($_POST['quote_source'] ?? 'manual')) ?: 'manual';

        if ($instrumentId <= 0 || $price <= 0) {
            throw new RuntimeException('Bitte Aktie und Kurs angeben.');
        }

        $this->storeQuote($instrumentId, $price, $currency, $quotedAt, $source);
        return 'Kurs gespeichert.';
    }

    private function refreshMarketDataPosition(): string
    {
        $positionId = (int) ($_POST['position_id'] ?? 0);
        $stmt = $this->pdo->prepare(
            'SELECT
                p.instrument_id,
                i.name AS instrument_name,
                i.symbol,
                i.isin,
                i.quote_currency
             FROM ' . $this->positionTable . ' p
             INNER JOIN ' . $this->instrumentTable . ' i ON i.id = p.instrument_id
             WHERE p.id = :id AND p.owner_sub = :owner_sub
             LIMIT 1'
        );
        $stmt->execute([
            'id' => $positionId,
            'owner_sub' => $this->ownerSub,
        ]);
        $row = $stmt->fetch(PDO::FETCH_ASSOC);
        if (!is_array($row)) {
            throw new RuntimeException('Position nicht gefunden.');
        }

        $instrumentId = (int) $row['instrument_id'];
        $symbol = strtoupper(trim((string) ($row['symbol'] ?? '')));
        $quoteCurrency = $this->normalizeCurrency((string) ($row['quote_currency'] ?? $this->defaultReportCurrency));
        if ($symbol === '') {
            throw new RuntimeException('Fuer diese Aktie ist noch kein Symbol hinterlegt.');
        }

        $latestApiQuote = $this->latestApiQuoteForInstrument($instrumentId);
        $latestTimestamp = is_array($latestApiQuote) ? strtotime((string) ($latestApiQuote['quoted_at'] ?? '')) : false;
        if ($latestTimestamp !== false && (time() - $latestTimestamp) < ($this->marketDataMinIntervalMinutes * 60)) {
            return 'Vorhandener Alpha-Vantage-Kurs fuer ' . (string) $row['instrument_name'] . ' wiederverwendet.';
        }

        $apiResult = \module_fn('boersenchecker', 'alpha_vantage_fetch_quote_by_symbol', $symbol);
        if (empty($apiResult['ok'])) {
            throw new RuntimeException((string) ($apiResult['message'] ?? 'API-Abruf fehlgeschlagen.'));
        }
        $fxResult = \module_fn('boersenchecker', 'fx_prepare_fetch', $this->defaultReportCurrency, [$quoteCurrency], $this->fxMaxAgeHours);
        if (empty($fxResult['ok'])) {
            throw new RuntimeException((string) ($fxResult['message'] ?? 'FX-Aktualisierung fehlgeschlagen.'));
        }
        $fxFetchId = is_numeric($fxResult['fetch_id'] ?? null) ? (int) $fxResult['fetch_id'] : null;
        if ($this->isApiSnapshotStale($latestApiQuote, (string) ($apiResult['fetched_at'] ?? ''))) {
            $displayTime = (string) \module_fn(
                'boersenchecker',
                'format_datetime_for_display',
                (string) ($apiResult['fetched_at'] ?? ''),
                (string) ($apiResult['source'] ?? 'alphavantage:global_quote')
            );
            return 'Alpha Vantage lieferte fuer ' . (string) $row['instrument_name'] . ' keinen neueren Snapshot als ' . $displayTime . '.';
        }

        $storeResult = \module_fn(
            'boersenchecker',
            'store_market_quote',
            $instrumentId,
            (float) $apiResult['price'],
            $quoteCurrency,
            (string) $apiResult['fetched_at'],
            (string) \module_fn('boersenchecker', 'fx_source_with_fetch_id', (string) $apiResult['source'], $fxFetchId)
        );
        if (!empty($storeResult['inserted'])) {
            return 'Alpha-Vantage-Kurs fuer ' . (string) $row['instrument_name'] . ' gespeichert.';
        }
        return 'Vorhandener Alpha-Vantage-Snapshot fuer ' . (string) $row['instrument_name'] . ' wiederverwendet.';
    }

    private function refreshMarketDataAll(): string
    {
        $stmt = $this->pdo->prepare(
            'SELECT DISTINCT
                i.id,
                i.name,
                i.symbol,
                i.isin,
                i.quote_currency
             FROM ' . $this->positionTable . ' p
             INNER JOIN ' . $this->instrumentTable . ' i ON i.id = p.instrument_id
             WHERE p.owner_sub = :owner_sub
             ORDER BY i.name ASC'
        );
        $stmt->execute(['owner_sub' => $this->ownerSub]);
        $rows = $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
        if ($rows === []) {
            throw new RuntimeException('Keine Positionen fuer den API-Abruf vorhanden.');
        }

        $fetched = 0;
        $reused = 0;
        $stale = 0;
        $skipped = 0;
        $failed = 0;
        $errors = [];

        $bulkRows = [];
        foreach ($rows as $row) {
            $instrumentId = (int) ($row['id'] ?? 0);
            $symbol = strtoupper(trim((string) ($row['symbol'] ?? '')));
            if ($instrumentId <= 0 || $symbol === '') {
                $skipped++;
                continue;
            }

            $latestApiQuote = $this->latestApiQuoteForInstrument($instrumentId);
            $latestTimestamp = is_array($latestApiQuote) ? strtotime((string) ($latestApiQuote['quoted_at'] ?? '')) : false;
            if ($latestTimestamp !== false && (time() - $latestTimestamp) < ($this->marketDataMinIntervalMinutes * 60)) {
                $reused++;
                continue;
            }

            $bulkRows[] = $row;
        }

        if ($bulkRows !== []) {
            $quoteCurrencies = array_values(array_unique(array_filter(array_map(
                fn (array $row): string => $this->normalizeCurrency((string) ($row['quote_currency'] ?? '')),
                $bulkRows
            ))));
            $fxResult = \module_fn('boersenchecker', 'fx_prepare_fetch', $this->defaultReportCurrency, $quoteCurrencies, $this->fxMaxAgeHours);
            if (empty($fxResult['ok'])) {
                throw new RuntimeException((string) ($fxResult['message'] ?? 'FX-Aktualisierung fehlgeschlagen.'));
            }
            $fxFetchId = is_numeric($fxResult['fetch_id'] ?? null) ? (int) $fxResult['fetch_id'] : null;

            $bulkResult = \module_fn('boersenchecker', 'alpha_vantage_fetch_quotes', $bulkRows);
            if (empty($bulkResult['ok'])) {
                throw new RuntimeException((string) ($bulkResult['message'] ?? 'Alpha-Vantage-Abruf fehlgeschlagen.'));
            }

            $bulkQuotes = is_array($bulkResult['quotes'] ?? null) ? $bulkResult['quotes'] : [];
            foreach ($bulkRows as $row) {
                $instrumentId = (int) ($row['id'] ?? 0);
                $quoteCurrency = $this->normalizeCurrency((string) ($row['quote_currency'] ?? $this->defaultReportCurrency));
                $apiResult = $bulkQuotes[$instrumentId] ?? null;
                if (!is_array($apiResult) || !is_numeric($apiResult['price'] ?? null)) {
                    $failed++;
                    $errors[] = (string) ($row['name'] ?? $instrumentId) . ': kein Preis in der Alpha-Vantage-Antwort.';
                    continue;
                }
                $latestApiQuote = $this->latestApiQuoteForInstrument($instrumentId);
                if ($this->isApiSnapshotStale($latestApiQuote, (string) ($apiResult['fetched_at'] ?? ''))) {
                    $stale++;
                    continue;
                }

                $storeResult = \module_fn(
                    'boersenchecker',
                    'store_market_quote',
                    $instrumentId,
                    (float) $apiResult['price'],
                    $quoteCurrency,
                    (string) $apiResult['fetched_at'],
                    (string) \module_fn('boersenchecker', 'fx_source_with_fetch_id', (string) $apiResult['source'], $fxFetchId)
                );
                if (!empty($storeResult['inserted'])) {
                    $fetched++;
                } else {
                    $reused++;
                }
            }
        }

        if ($errors !== []) {
            throw new RuntimeException(
                'Alpha Vantage: ' . $fetched . ' neu, ' . $reused . ' wiederverwendet, ' . $stale . ' nicht neuer, ' . $skipped . ' ohne Symbol, ' . $failed . ' Fehler. '
                . implode(' | ', array_slice($errors, 0, 3))
            );
        }

        return 'Alpha Vantage: ' . $fetched . ' neu, ' . $reused . ' wiederverwendet, ' . $stale . ' nicht neuer, ' . $skipped . ' ohne Symbol, ' . $failed . ' Fehler.';
    }

    private function searchSymbol(): string
    {
        $keywords = trim((string) ($_POST['search_keywords'] ?? ''));
        $this->symbolSearchKeywords = $keywords;
        $result = \module_fn('boersenchecker', 'alpha_vantage_search_symbols', $keywords);
        $this->symbolSearchResults = is_array($result['results'] ?? null) ? $result['results'] : [];

        if (empty($result['ok'])) {
            throw new RuntimeException((string) ($result['message'] ?? 'Symbolsuche fehlgeschlagen.'));
        }

        return (string) ($result['message'] ?? 'Suche abgeschlossen.');
    }

    private function deleteQuote(): string
    {
        $quoteId = (int) ($_POST['quote_id'] ?? 0);
        $stmt = $this->pdo->prepare(
            'DELETE FROM ' . $this->quoteTable . '
             WHERE id = :id
               AND instrument_id IN (
                   SELECT DISTINCT instrument_id
                   FROM ' . $this->positionTable . '
                   WHERE owner_sub = :owner_sub
               )'
        );
        $stmt->execute([
            'id' => $quoteId,
            'owner_sub' => $this->ownerSub,
        ]);
        return 'Kurseintrag geloescht.';
    }

    private function refreshFx(): string
    {
        $result = \module_fn('boersenchecker', 'fx_refresh', $this->defaultReportCurrency, $this->fxMaxAgeHours);
        if (empty($result['ok'])) {
            throw new RuntimeException((string) ($result['message'] ?? 'FX-Aktualisierung fehlgeschlagen.'));
        }
        return (string) ($result['message'] ?? 'FX-Daten aktualisiert.');
    }

    private function fetchPortfolios(): array
    {
        $stmt = $this->pdo->prepare('SELECT * FROM ' . $this->portfolioTable . ' WHERE owner_sub = :owner_sub ORDER BY name ASC');
        $stmt->execute(['owner_sub' => $this->ownerSub]);
        return $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
    }

    private function fetchPositions(): array
    {
        $stmt = $this->pdo->prepare(
            'SELECT
                p.*,
                i.isin,
                i.wkn,
                i.symbol,
                i.name AS instrument_name,
                i.quote_currency,
                i.market
             FROM ' . $this->positionTable . ' p
             INNER JOIN ' . $this->instrumentTable . ' i ON i.id = p.instrument_id
             WHERE p.owner_sub = :owner_sub
             ORDER BY p.purchase_date DESC, p.id DESC'
        );
        $stmt->execute(['owner_sub' => $this->ownerSub]);
        return $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
    }

    private function buildInstrumentList(array $positions): array
    {
        $instrumentList = [];
        foreach ($positions as $position) {
            $instrumentId = (int) $position['instrument_id'];
            if (!isset($instrumentList[$instrumentId])) {
                $instrumentList[$instrumentId] = [
                    'id' => $instrumentId,
                    'name' => (string) $position['instrument_name'],
                    'symbol' => (string) ($position['symbol'] ?? ''),
                    'isin' => (string) ($position['isin'] ?? ''),
                    'quote_currency' => (string) ($position['quote_currency'] ?? ''),
                ];
            }
        }
        return $instrumentList;
    }

    private function fetchQuotes(array $instrumentIds): array
    {
        $quoteHistory = [];
        $latestQuotes = [];
        if ($instrumentIds === []) {
            return [$quoteHistory, $latestQuotes];
        }

        $placeholders = implode(',', array_fill(0, count($instrumentIds), '?'));
        $stmt = $this->pdo->prepare(
            'SELECT *
             FROM ' . $this->quoteTable . '
             WHERE instrument_id IN (' . $placeholders . ')
             ORDER BY quoted_at DESC, created_at DESC, id DESC'
        );
        $stmt->execute($instrumentIds);
        $quotes = $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
        foreach ($quotes as $quote) {
            $instrumentId = (int) $quote['instrument_id'];
            $quoteHistory[$instrumentId][] = $quote;
            if (!isset($latestQuotes[$instrumentId])) {
                $latestQuotes[$instrumentId] = $quote;
            }
        }

        return [$quoteHistory, $latestQuotes];
    }

    private function buildPortfolioById(array $portfolios): array
    {
        $portfolioById = [];
        foreach ($portfolios as $portfolio) {
            $portfolio['base_currency'] = $this->normalizeCurrency((string) ($portfolio['base_currency'] ?? $this->defaultReportCurrency));
            $portfolioById[(int) $portfolio['id']] = $portfolio;
        }
        return $portfolioById;
    }

    private function enrichPositions(array $positions, array $portfolioById, array $latestQuotes): array
    {
        $portfolioStats = [];
        foreach ($portfolioById as $portfolioId => $portfolio) {
            $portfolioStats[$portfolioId] = [
                'invested' => 0.0,
                'current' => 0.0,
                'gain' => 0.0,
                'positions' => 0,
                'has_invested' => false,
                'has_current' => false,
            ];
        }

        foreach ($positions as &$position) {
            $portfolioId = (int) $position['portfolio_id'];
            $baseCurrency = (string) ($portfolioById[$portfolioId]['base_currency'] ?? $this->defaultReportCurrency);
            $quantity = (float) $position['quantity'];
            $purchasePrice = (float) $position['purchase_price'];
            $fees = is_numeric($position['fees'] ?? null) ? (float) $position['fees'] : 0.0;
            $purchaseTotal = ($quantity * $purchasePrice) + $fees;
            $purchaseTotalBase = $this->convertAmount($purchaseTotal, (string) $position['purchase_currency'], $baseCurrency);
            $latestQuote = $latestQuotes[(int) $position['instrument_id']] ?? null;
            $currentTotalBase = null;

            if (is_array($latestQuote) && is_numeric($latestQuote['price'] ?? null)) {
                $currentOriginal = $quantity * (float) $latestQuote['price'];
                $currentTotalBase = $this->convertAmount($currentOriginal, (string) $latestQuote['currency'], $baseCurrency, (string) ($latestQuote['source'] ?? ''));
                $position['latest_price'] = (float) $latestQuote['price'];
                $position['latest_currency'] = (string) $latestQuote['currency'];
                $position['latest_quoted_at'] = (string) $latestQuote['quoted_at'];
                $position['latest_source'] = (string) ($latestQuote['source'] ?? '');
                $position['current_total_base'] = $currentTotalBase;
            } else {
                $position['latest_price'] = null;
                $position['latest_currency'] = null;
                $position['latest_quoted_at'] = null;
                $position['latest_source'] = null;
                $position['current_total_base'] = null;
            }

            $position['purchase_total'] = $purchaseTotal;
            $position['purchase_total_base'] = $purchaseTotalBase;
            $position['base_currency'] = $baseCurrency;
            $position['gain_base'] = $currentTotalBase !== null && $purchaseTotalBase !== null
                ? $currentTotalBase - $purchaseTotalBase
                : null;

            if (isset($portfolioStats[$portfolioId])) {
                $portfolioStats[$portfolioId]['positions']++;
                if ($purchaseTotalBase !== null) {
                    $portfolioStats[$portfolioId]['invested'] += $purchaseTotalBase;
                    $portfolioStats[$portfolioId]['has_invested'] = true;
                }
                if ($currentTotalBase !== null) {
                    $portfolioStats[$portfolioId]['current'] += $currentTotalBase;
                    $portfolioStats[$portfolioId]['has_current'] = true;
                }
            }
        }
        unset($position);

        foreach ($portfolioStats as &$stats) {
            $stats['gain'] = ($stats['has_invested'] && $stats['has_current'])
                ? $stats['current'] - $stats['invested']
                : null;
        }
        unset($stats);

        return [$positions, $portfolioStats];
    }

    private function latestApiQuoteForInstrument(int $instrumentId): ?array
    {
        $stmt = $this->pdo->prepare(
            'SELECT *
             FROM ' . $this->quoteTable . '
             WHERE instrument_id = :instrument_id
               AND source LIKE :source
             ORDER BY quoted_at DESC, created_at DESC, id DESC
             LIMIT 1'
        );
        $stmt->execute([
            'instrument_id' => $instrumentId,
            'source' => 'alphavantage:%',
        ]);
        $row = $stmt->fetch(PDO::FETCH_ASSOC);
        return is_array($row) ? $row : null;
    }

    private function isApiSnapshotStale(?array $latestQuote, string $incomingQuotedAt): bool
    {
        if (!is_array($latestQuote)) {
            return false;
        }

        $latestTimestamp = strtotime((string) ($latestQuote['quoted_at'] ?? ''));
        $incomingTimestamp = strtotime(trim($incomingQuotedAt));
        if ($latestTimestamp === false || $incomingTimestamp === false) {
            return false;
        }

        return $incomingTimestamp <= $latestTimestamp;
    }

    private function upsertInstrument(array $payload): int
    {
        return $this->instrumentRegistry->save($payload);
    }

    private function storeQuote(int $instrumentId, float $price, string $currency, string $quotedAt, string $source): void
    {
        $stmt = $this->pdo->prepare(
            'INSERT INTO ' . $this->quoteTable . ' (instrument_id, price, currency, quoted_at, source)
             VALUES (:instrument_id, :price, :currency, :quoted_at, :source)'
        );
        $stmt->execute([
            'instrument_id' => $instrumentId,
            'price' => $price,
            'currency' => $currency,
            'quoted_at' => $quotedAt,
            'source' => $source,
        ]);
    }

    private function convertAmount(?float $amount, string $from, string $to, ?string $quoteSource = null): ?float
    {
        if ($amount === null) {
            return null;
        }

        $from = $this->normalizeCurrency($from);
        $to = $this->normalizeCurrency($to);
        if ($from === $to) {
            return $amount;
        }

        try {
            $fetchId = (int) (\module_fn('boersenchecker', 'fx_extract_fetch_id', (string) $quoteSource) ?? 0);
            $value = \module_fn('boersenchecker', 'fx_convert_with_fetch', $amount, $from, $to, $fetchId > 0 ? $fetchId : null);
            return is_numeric($value) ? (float) $value : null;
        } catch (\Throwable) {
            return null;
        }
    }

    private function normalizeCurrency(?string $value, string $fallback = 'EUR'): string
    {
        $normalized = strtoupper(trim((string) $value));
        return $normalized !== '' ? $normalized : $fallback;
    }

    private function normalizeDateTimeLocal(?string $value): string
    {
        $timezone = new \DateTimeZone('Europe/Berlin');
        $value = trim((string) $value);
        if ($value === '') {
            return (new \DateTimeImmutable('now', $timezone))->format('Y-m-d H:i:s');
        }

        $date = \DateTimeImmutable::createFromFormat('Y-m-d\TH:i', $value, $timezone);
        if ($date instanceof \DateTimeImmutable) {
            return $date->format('Y-m-d H:i:s');
        }

        try {
            return (new \DateTimeImmutable($value, $timezone))->format('Y-m-d H:i:s');
        } catch (\Throwable) {
            return (new \DateTimeImmutable('now', $timezone))->format('Y-m-d H:i:s');
        }
    }

    private function formatNumber(?float $value, int $scale = 2): string
    {
        if ($value === null) {
            return 'n/a';
        }

        return number_format($value, $scale, ',', '.');
    }

    private function buildAvailableOwners(): array
    {
        $owners = [];
        $currentSub = trim((string) ($this->user['sub'] ?? 'local'));
        $owners[$currentSub] = [
            'sub' => $currentSub,
            'label' => trim((string) ($this->user['name'] ?? $this->user['email'] ?? $currentSub)) ?: $currentSub,
        ];

        if (!$this->isAdmin) {
            return $owners;
        }

        foreach (\modules()->knownAuthUsers() as $knownUser) {
            $sub = trim((string) ($knownUser['sub'] ?? ''));
            if ($sub === '') {
                continue;
            }
            $label = trim((string) ($knownUser['name'] ?? $knownUser['email'] ?? $knownUser['username'] ?? $sub));
            $owners[$sub] = [
                'sub' => $sub,
                'label' => $label !== '' ? $label : $sub,
            ];
        }

        uasort($owners, static fn (array $left, array $right): int => strcmp((string) $left['label'], (string) $right['label']));
        return $owners;
    }
}