<?php
declare(strict_types=1);

function payload_first_non_empty(array $data, array $keys, string $default = ''): string
{
    foreach ($keys as $key) {
        $value = trim((string) ($data[$key] ?? ''));
        if ($value !== '') {
            return $value;
        }
    }

    return $default;
}

function find_or_create_party(PDO $pdo, array $data): int
{
    $email = payload_first_non_empty($data, ['E-Mail', 'email', 'EmailKunde']);
    if ($email !== '') {
        $stmt = $pdo->prepare('SELECT id FROM party WHERE email = :email LIMIT 1');
        $stmt->execute([':email' => $email]);
        $existing = $stmt->fetchColumn();
        if ($existing !== false) {
            return (int) $existing;
        }
    }

    $name = trim(
        payload_first_non_empty($data, ['Vorname', 'firstName', 'Vorname_RgAdr', 'Vorname_LfAdr']) . ' ' .
        payload_first_non_empty($data, ['Nachname', 'lastName', 'Nachname_RgAdr', 'Nachname_LfAdr'])
    );
    $name = trim($name);
    if ($name === '') {
        $name = payload_first_non_empty($data, ['Firmenname', 'company']);
    }
    if ($name === '') {
        $name = 'Unbekannter Kontakt';
    }

    $stmt = $pdo->prepare(
        "INSERT INTO party (type, name, email, status, created_at, updated_at)
         VALUES ('customer', :name, :email, 'active', NOW(), NOW())
         RETURNING id"
    );
    $stmt->execute([
        ':name' => $name,
        ':email' => $email !== '' ? $email : null,
    ]);

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

    return (int) $id;
}

function upsert_addresses(PDO $pdo, int $partyId, array $data): void
{
    $addressData = [
        'billing' => [
            'first_name' => payload_first_non_empty($data, ['Vorname', 'firstName', 'Vorname_RgAdr']),
            'last_name' => payload_first_non_empty($data, ['Nachname', 'lastName', 'Nachname_RgAdr']),
            'street' => payload_first_non_empty($data, ['Strasse', 'street', 'Strasse_RgAdr']),
            'house_number' => payload_first_non_empty($data, ['Hausnummer', 'houseNumber', 'Hausnummer_RgAdr']),
            'zip' => payload_first_non_empty($data, ['PLZ', 'zip', 'PLZ_RgAdr']),
            'city' => payload_first_non_empty($data, ['Ort', 'city', 'Stadt_RgAdr']),
            'country_name' => payload_first_non_empty($data, ['Land', 'country', 'Land_RgAdr'], 'Switzerland'),
        ],
        'shipping' => [
            'first_name' => payload_first_non_empty($data, ['Vorname_LfAdr']),
            'last_name' => payload_first_non_empty($data, ['Nachname_LfAdr']),
            'street' => payload_first_non_empty($data, ['Strasse_LfAdr']),
            'house_number' => payload_first_non_empty($data, ['Hausnummer_LfAdr']),
            'zip' => payload_first_non_empty($data, ['PLZ_LfAdr']),
            'city' => payload_first_non_empty($data, ['Stadt_LfAdr', 'Ort_LfAdr']),
            'country_name' => payload_first_non_empty($data, ['Land_LfAdr'], 'Switzerland'),
        ],
    ];

    foreach ($addressData as $type => $address) {
        if ($address['street'] === '' && $address['city'] === '' && $address['zip'] === '') {
            continue;
        }

        $stmt = $pdo->prepare(
            "INSERT INTO address (
                party_id, type, first_name, last_name, street, house_number, zip, city, country_name, created_at, updated_at
             ) VALUES (
                :party_id, :type, :first_name, :last_name, :street, :house_number, :zip, :city, :country_name, NOW(), NOW()
             )"
        );
        $stmt->execute([
            ':party_id' => $partyId,
            ':type' => $type,
            ':first_name' => $address['first_name'],
            ':last_name' => $address['last_name'],
            ':street' => $address['street'],
            ':house_number' => $address['house_number'],
            ':zip' => $address['zip'],
            ':city' => $address['city'],
            ':country_name' => $address['country_name'] !== '' ? $address['country_name'] : 'Switzerland',
        ]);
    }
}

function get_manufacturer_options(PDO $pdo): array
{
    $stmt = $pdo->query(
        "SELECT p.id, p.name, p.email, p.phone
         FROM party p
         INNER JOIN party_role pr ON pr.party_id = p.id AND pr.role_code = 'manufacturer'
         WHERE p.status = 'active'
         ORDER BY p.name ASC, p.id ASC"
    );

    return array_map(
        static fn (array $row): array => [
            'id' => (int) $row['id'],
            'name' => (string) $row['name'],
            'email' => (string) ($row['email'] ?? ''),
            'phone' => (string) ($row['phone'] ?? ''),
        ],
        $stmt->fetchAll()
    );
}

function get_party_reference(PDO $pdo, int $partyId): ?array
{
    $stmt = $pdo->prepare(
        'SELECT id, name, email, phone
         FROM party
         WHERE id = :id'
    );
    $stmt->execute([':id' => $partyId]);
    $party = $stmt->fetch();

    return is_array($party) ? $party : null;
}

function get_contact_reference(PDO $pdo, int $contactId): ?array
{
    $stmt = $pdo->prepare(
        'SELECT id, party_id, first_name, last_name, email, phone, position_title
         FROM contact
         WHERE id = :id'
    );
    $stmt->execute([':id' => $contactId]);
    $contact = $stmt->fetch();

    return is_array($contact) ? $contact : null;
}

function get_party_options(PDO $pdo): array
{
    $stmt = $pdo->query(
        "SELECT id, name
         FROM party
         WHERE status = 'active'
         ORDER BY name ASC, id ASC"
    );

    return array_map(
        static fn (array $row): array => ['id' => (int) $row['id'], 'name' => (string) ($row['name'] ?? '')],
        $stmt->fetchAll()
    );
}

function get_contact_options(PDO $pdo): array
{
    $stmt = $pdo->query(
        "SELECT c.id, c.party_id, c.first_name, c.last_name, p.name AS party_name
         FROM contact c
         INNER JOIN party p ON p.id = c.party_id
         WHERE p.status = 'active'
         ORDER BY p.name ASC, c.last_name ASC, c.first_name ASC, c.id ASC"
    );

    return array_map(
        static fn (array $row): array => [
            'id' => (int) $row['id'],
            'party_id' => (int) $row['party_id'],
            'first_name' => (string) ($row['first_name'] ?? ''),
            'last_name' => (string) ($row['last_name'] ?? ''),
            'party_name' => (string) ($row['party_name'] ?? ''),
        ],
        $stmt->fetchAll()
    );
}

function update_contact_details(PDO $pdo, int $contactId, array $input): array
{
    if ($contactId <= 0) {
        throw new InvalidArgumentException('contact_person_id muss positiv sein.');
    }

    $sets = [];
    $params = [':id' => $contactId];
    foreach (['email', 'phone'] as $field) {
        if (array_key_exists($field, $input)) {
            $sets[] = $field . ' = :' . $field;
            $value = trim((string) ($input[$field] ?? ''));
            $params[':' . $field] = $value !== '' ? $value : null;
        }
    }
    if ($sets === []) {
        throw new InvalidArgumentException('Keine änderbaren Kontaktdaten übergeben.');
    }

    $sets[] = 'updated_at = NOW()';
    $stmt = $pdo->prepare(
        'UPDATE contact SET ' . implode(', ', $sets) . ' WHERE id = :id
         RETURNING id, party_id, first_name, last_name, email, phone, position_title'
    );
    $stmt->execute($params);
    $contact = $stmt->fetch();
    if (!is_array($contact)) {
        throw new RuntimeException('Kontaktperson nicht gefunden.');
    }
    return $contact;
}

function create_manufacturer(PDO $pdo, string $name, ?string $email = null, ?string $phone = null): array
{
    $name = trim($name);
    $email = $email !== null ? trim($email) : null;
    $phone = $phone !== null ? trim($phone) : null;

    if ($name === '') {
        throw new InvalidArgumentException('Herstellername fehlt');
    }

    $existingStmt = $pdo->prepare(
        "SELECT p.id, p.name, p.email, p.phone
         FROM party p
         WHERE LOWER(TRIM(p.name)) = LOWER(:name)
         LIMIT 1
         FOR UPDATE"
    );
    $existingStmt->execute([':name' => $name]);
    $existing = $existingStmt->fetch();
    if (is_array($existing)) {
        $roleStmt = $pdo->prepare(
            "INSERT INTO party_role (party_id, role_code) VALUES (:party_id, 'manufacturer')
             ON CONFLICT (party_id, role_code) DO NOTHING"
        );
        $roleStmt->execute([':party_id' => (int) $existing['id']]);
        return [
            'id' => (int) $existing['id'],
            'name' => (string) $existing['name'],
            'email' => (string) ($existing['email'] ?? ''),
            'phone' => (string) ($existing['phone'] ?? ''),
        ];
    }

    $stmt = $pdo->prepare(
        "INSERT INTO party (type, name, email, phone, status, created_at, updated_at)
         VALUES ('supplier', :name, :email, :phone, 'active', NOW(), NOW())
         RETURNING id, name, email, phone"
    );
    $stmt->execute([
        ':name' => $name,
        ':email' => $email !== '' ? $email : null,
        ':phone' => $phone !== '' ? $phone : null,
    ]);
    $party = $stmt->fetch();
    if (!is_array($party)) {
        throw new RuntimeException('Hersteller konnte nicht angelegt werden');
    }

    $roleStmt = $pdo->prepare(
        "INSERT INTO party_role (party_id, role_code) VALUES (:party_id, 'manufacturer')"
    );
    $roleStmt->execute([':party_id' => (int) $party['id']]);

    return [
        'id' => (int) $party['id'],
        'name' => (string) $party['name'],
        'email' => (string) ($party['email'] ?? ''),
        'phone' => (string) ($party['phone'] ?? ''),
    ];
}