<?php
declare(strict_types=1);

function lookup_method_id(PDO $pdo, string $table, ?string $code): ?int
{
    if ($code === null || $code === '') {
        return null;
    }

    $stmt = $pdo->prepare("SELECT id FROM public.{$table} WHERE code = :code LIMIT 1");
    $stmt->execute([':code' => $code]);
    $id = $stmt->fetchColumn();

    return $id === false ? null : (int) $id;
}

function map_payment_code(string $input): ?string
{
    $v = strtolower(trim($input));
    if ($v === '') {
        return null;
    }

    if (str_contains($v, 'twint')) {
        return 'twint';
    }
    if (str_contains($v, 'bank') || str_contains($v, 'vorauskasse') || str_contains($v, 'ueberweisung')) {
        return 'bank_transfer';
    }
    if (str_contains($v, 'kredit') || str_contains($v, 'debit') || str_contains($v, 'card')) {
        return 'card';
    }

    return null;
}

function map_shipping_code(string $input): ?string
{
    $v = strtolower(trim($input));
    if ($v === '') {
        return null;
    }

    if (str_contains($v, 'abholung') || str_contains($v, 'pickup')) {
        return 'pickup';
    }
    if (str_contains($v, 'post') || str_contains($v, 'versand')) {
        return 'post_standard';
    }

    return null;
}

function ensure_required_tables_exist(PDO $pdo): void
{
    $required = [
        'party',
        'address',
        'sales_order',
        'sales_order_line',
        'payment_method',
        'shipping_method',
    ];

    $stmt = $pdo->query(
        "SELECT table_name
         FROM information_schema.tables
         WHERE table_schema = 'public'"
    );
    $rows = $stmt->fetchAll(PDO::FETCH_COLUMN);
    $existing = array_map('strval', $rows ?: []);
    $missing = array_values(array_diff($required, $existing));

    if ($missing !== []) {
        throw new RuntimeException('DB schema not initialized. Missing tables: ' . implode(', ', $missing));
    }
}

function find_existing_order_id(PDO $pdo, string $externalRef): ?int
{
    $stmt = $pdo->prepare('SELECT id FROM sales_order WHERE external_ref = :external_ref LIMIT 1');
    $stmt->execute([':external_ref' => $externalRef]);
    $id = $stmt->fetchColumn();

    return $id === false ? null : (int) $id;
}

function upsert_sales_order(PDO $pdo, array $fields): int
{
    $stmt = $pdo->prepare(
        'INSERT INTO public.sales_order (
            external_ref, party_id, order_source, order_status, payment_status, payment_method_id, shipping_method_id,
            amount_net, amount_shipping, amount_tax, amount_discount, total_amount, currency, webhook_payload, imported_at, created_at, updated_at
         ) VALUES (
            :external_ref, :party_id, :order_source, :order_status, :payment_status, :payment_method_id, :shipping_method_id,
            :amount_net, :amount_shipping, :amount_tax, :amount_discount, :total_amount, :currency, :webhook_payload::jsonb, NOW(), NOW(), NOW()
         )
         ON CONFLICT (external_ref) DO UPDATE SET
            party_id = EXCLUDED.party_id,
            order_source = EXCLUDED.order_source,
            order_status = EXCLUDED.order_status,
            payment_status = EXCLUDED.payment_status,
            payment_method_id = EXCLUDED.payment_method_id,
            shipping_method_id = EXCLUDED.shipping_method_id,
            amount_net = EXCLUDED.amount_net,
            amount_shipping = EXCLUDED.amount_shipping,
            amount_tax = EXCLUDED.amount_tax,
            amount_discount = EXCLUDED.amount_discount,
            total_amount = EXCLUDED.total_amount,
            currency = EXCLUDED.currency,
            webhook_payload = EXCLUDED.webhook_payload,
            imported_at = NOW(),
            updated_at = NOW()
         RETURNING id'
    );
    $stmt->execute($fields);

    $id = $stmt->fetchColumn();
    if ($id === false) {
        throw new RuntimeException('Could not upsert order');
    }

    return (int) $id;
}

function create_direct_sales_order(PDO $pdo, array $fields): array
{
    $stmt = $pdo->prepare(
        "INSERT INTO sales_order (
            external_ref, party_id, order_source, order_status, payment_status, payment_method_id,
            amount_net, amount_shipping, amount_tax, amount_discount, total_amount, currency, imported_at, created_at, updated_at
         ) VALUES (
            '', :party_id, 'direct', 'imported', 'paid', :payment_method_id,
            :amount_net, 0, 0, 0, :total_amount, 'CHF', NOW(), NOW(), NOW()
         )
         RETURNING id, external_ref"
    );
    $stmt->execute($fields);

    $row = $stmt->fetch();
    if ($row === false) {
        throw new RuntimeException('Could not create order');
    }

    return [
        'id' => (int) $row['id'],
        'external_ref' => (string) $row['external_ref'],
    ];
}

function delete_sales_order_lines(PDO $pdo, int $orderId): void
{
    $deleteLines = $pdo->prepare('DELETE FROM public.sales_order_line WHERE sales_order_id = :sales_order_id');
    $deleteLines->execute([':sales_order_id' => $orderId]);
}

function insert_sales_order_line(PDO $pdo, array $fields): int
{
    $stmt = $pdo->prepare(
        'INSERT INTO public.sales_order_line (
            sales_order_id, line_no, sellable_item_id, raw_external_article_number, raw_external_title,
            qty, unit_price, line_total, created_at, updated_at
         ) VALUES (
            :sales_order_id, :line_no, :sellable_item_id, :article_number, :title,
            :qty, :unit_price, :line_total, NOW(), NOW()
         )
         RETURNING id'
    );
    $stmt->execute($fields);

    $id = $stmt->fetchColumn();
    if ($id === false) {
        throw new RuntimeException('Could not insert sales_order_line');
    }

    return (int) $id;
}