<?php
declare(strict_types=1);

namespace Modules\Boersenchecker\Support;

use PDO;
use RuntimeException;

final class InstrumentPage
{
    private PDO $pdo;
    private string $ownerSub;
    private string $instrumentTable;
    private string $positionTable;
    private string $quoteTable;
    private string $defaultReportCurrency;
    private float $fxMaxAgeHours;
    private string $searchKeywords = '';
    private array $searchResults = [];
    private int $selectedInstrumentOverrideId = 0;
    private InstrumentRegistry $instrumentRegistry;

    public function __construct()
    {
        $this->pdo = \module_fn('boersenchecker', 'pdo');
        \module_fn('boersenchecker', 'ensure_schema');
        $user = \auth_user() ?? [];
        $this->ownerSub = trim((string) ($user['sub'] ?? 'local'));

        $settings = \modules()->settings('boersenchecker');
        $this->defaultReportCurrency = strtoupper(trim((string) ($settings['report_currency'] ?? 'EUR'))) ?: 'EUR';
        $this->fxMaxAgeHours = (float) ($settings['fx_max_age_hours'] ?? 6);
        if ($this->fxMaxAgeHours <= 0) {
            $this->fxMaxAgeHours = 6.0;
        }
        $table = static fn (string $name): string => \module_fn('boersenchecker', 'table', $name);
        $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();
            }
        }

        $instruments = $this->fetchInstruments();
        $selectedInstrumentId = $this->selectedInstrumentOverrideId > 0
            ? $this->selectedInstrumentOverrideId
            : (int) ($_GET['instrument_id'] ?? ($_POST['instrument_id'] ?? 0));
        if ($selectedInstrumentId <= 0 && $instruments !== []) {
            $selectedInstrumentId = (int) $instruments[0]['id'];
        }

        $selectedInstrument = null;
        foreach ($instruments as $instrument) {
            if ((int) $instrument['id'] === $selectedInstrumentId) {
                $selectedInstrument = $instrument;
                break;
            }
        }

        $quotes = $selectedInstrumentId > 0 ? $this->fetchQuotes($selectedInstrumentId) : [];

        $candidateName = trim((string) ($_GET['instrument_name_candidate'] ?? ''));
        $candidateSymbol = trim((string) ($_GET['symbol_candidate'] ?? ''));
        $candidateIsin = trim((string) ($_GET['isin_candidate'] ?? ''));
        $candidateMarket = trim((string) ($_GET['market_candidate'] ?? ''));
        $candidateCurrency = strtoupper(trim((string) ($_GET['quote_currency_candidate'] ?? $this->defaultReportCurrency))) ?: $this->defaultReportCurrency;
        if ($selectedInstrument === null && ($candidateName !== '' || $candidateSymbol !== '' || $candidateMarket !== '')) {
            $selectedInstrument = [
                'id' => 0,
                'name' => $candidateName,
                'symbol' => $candidateSymbol,
                'isin' => $candidateIsin,
                'market' => $candidateMarket,
                'quote_currency' => $candidateCurrency,
                'wkn' => '',
            ];
        }

        return [
            'notice' => $notice,
            'error' => $error,
            'instruments' => $instruments,
            'selectedInstrument' => $selectedInstrument,
            'selectedInstrumentId' => $selectedInstrumentId,
            'quotes' => $quotes,
            'searchKeywords' => $this->searchKeywords,
            'searchResults' => $this->searchResults,
            'defaultReportCurrency' => $this->defaultReportCurrency,
            '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_instrument' => $this->saveInstrument(),
            'save_quote' => $this->saveQuote(),
            'delete_quote' => $this->deleteQuote(),
            'refresh_market_data_instrument' => $this->refreshInstrumentQuote(),
            'search_symbol' => $this->searchSymbol(),
            default => '',
        };
    }

    private function fetchInstruments(): array
    {
        $stmt = $this->pdo->prepare(
            'SELECT DISTINCT i.*
             FROM ' . $this->instrumentTable . ' i
             INNER JOIN ' . $this->positionTable . ' p ON p.instrument_id = i.id
             WHERE p.owner_sub = :owner_sub
             ORDER BY i.name ASC'
        );
        $stmt->execute(['owner_sub' => $this->ownerSub]);
        return $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
    }

    private function fetchQuotes(int $instrumentId): array
    {
        $stmt = $this->pdo->prepare(
            'SELECT *
             FROM ' . $this->quoteTable . '
             WHERE instrument_id = :instrument_id
             ORDER BY quoted_at DESC, created_at DESC, id DESC
             LIMIT 30'
        );
        $stmt->execute(['instrument_id' => $instrumentId]);
        return $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];
    }

    private function saveInstrument(): string
    {
        $instrumentId = (int) ($_POST['instrument_id'] ?? 0);
        if ($instrumentId <= 0) {
            throw new RuntimeException('Bitte eine Aktie auswaehlen.');
        }
        $this->assertInstrumentAccessible($instrumentId);

        $resolvedId = $this->instrumentRegistry->save([
            'id' => $instrumentId,
            'name' => $_POST['instrument_name'] ?? '',
            'symbol' => $_POST['symbol'] ?? '',
            'isin' => $_POST['isin'] ?? '',
            'wkn' => $_POST['wkn'] ?? '',
            'market' => $_POST['market'] ?? '',
            'quote_currency' => $_POST['quote_currency'] ?? $this->defaultReportCurrency,
        ]);
        $this->selectedInstrumentOverrideId = $resolvedId;

        return $resolvedId === $instrumentId
            ? 'Aktie aktualisiert.'
            : 'Aktie aktualisiert und mit bestehendem Systemeintrag zusammengefuehrt.';
    }

    private function saveQuote(): string
    {
        $instrumentId = (int) ($_POST['instrument_id'] ?? 0);
        $price = (float) ($_POST['quote_price'] ?? 0);
        if ($instrumentId <= 0 || $price <= 0) {
            throw new RuntimeException('Bitte Aktie und Kurs angeben.');
        }
        $this->assertInstrumentAccessible($instrumentId);

        $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' => $price,
            'currency' => strtoupper(trim((string) ($_POST['quote_currency'] ?? $this->defaultReportCurrency))) ?: $this->defaultReportCurrency,
            'quoted_at' => $this->normalizeDateTimeLocal((string) ($_POST['quoted_at'] ?? '')),
            'source' => trim((string) ($_POST['quote_source'] ?? 'manual')) ?: 'manual',
        ]);
        return 'Kurs gespeichert.';
    }

    private function deleteQuote(): string
    {
        $quoteId = (int) ($_POST['quote_id'] ?? 0);
        if ($quoteId <= 0) {
            throw new RuntimeException('Bitte einen Kurseintrag auswaehlen.');
        }

        $stmt = $this->pdo->prepare(
            'SELECT q.instrument_id
             FROM ' . $this->quoteTable . ' q
             WHERE q.id = :id
             LIMIT 1'
        );
        $stmt->execute(['id' => $quoteId]);
        $instrumentId = (int) $stmt->fetchColumn();
        $this->assertInstrumentAccessible($instrumentId);

        $stmt = $this->pdo->prepare('DELETE FROM ' . $this->quoteTable . ' WHERE id = :id');
        $stmt->execute(['id' => $quoteId]);
        return 'Kurs geloescht.';
    }

    private function refreshInstrumentQuote(): string
    {
        $instrumentId = (int) ($_POST['instrument_id'] ?? 0);
        $instrument = $this->assertInstrumentAccessible($instrumentId);
        $symbol = strtoupper(trim((string) ($instrument['symbol'] ?? '')));
        if ($symbol === '') {
            throw new RuntimeException('Fuer diese Aktie ist kein Symbol hinterlegt.');
        }

        $apiResult = \module_fn('boersenchecker', 'alpha_vantage_fetch_quote_by_symbol', $symbol);
        if (empty($apiResult['ok'])) {
            throw new RuntimeException((string) ($apiResult['message'] ?? 'API-Abruf fehlgeschlagen.'));
        }
        $quoteCurrency = strtoupper(trim((string) ($instrument['quote_currency'] ?? $this->defaultReportCurrency))) ?: $this->defaultReportCurrency;
        $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;
        $latestApiQuote = $this->latestApiQuoteForInstrument($instrumentId);
        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 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)
        );

        return !empty($storeResult['inserted'])
            ? 'Alpha-Vantage-Kurs gespeichert.'
            : 'Vorhandener Alpha-Vantage-Snapshot wiederverwendet.';
    }

    private function searchSymbol(): string
    {
        $this->searchKeywords = trim((string) ($_POST['search_keywords'] ?? ''));
        $result = \module_fn('boersenchecker', 'alpha_vantage_search_symbols', $this->searchKeywords);
        $this->searchResults = is_array($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 assertInstrumentAccessible(int $instrumentId): array
    {
        if ($instrumentId <= 0) {
            throw new RuntimeException('Aktie nicht gefunden.');
        }

        $stmt = $this->pdo->prepare(
            'SELECT DISTINCT i.*
             FROM ' . $this->instrumentTable . ' i
             INNER JOIN ' . $this->positionTable . ' p ON p.instrument_id = i.id
             WHERE i.id = :id AND p.owner_sub = :owner_sub
             LIMIT 1'
        );
        $stmt->execute([
            'id' => $instrumentId,
            'owner_sub' => $this->ownerSub,
        ]);
        $instrument = $stmt->fetch(PDO::FETCH_ASSOC);
        if (!is_array($instrument)) {
            throw new RuntimeException('Aktie ist nicht verfuegbar.');
        }

        return $instrument;
    }

    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 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;
    }
}