<?php
require_once __DIR__ . '/../module/mailer.php';
require_once __DIR__ . '/../secret_box.php';

class SmtpManager
{
    private PDO $pdo;
    private int $companyId;
    private string $method;
    private string $pinkey;
    private string $iv;

    public function __construct(PDO $pdo, int $company_id, string $method, string $pinkey, string $iv)
    {
        $this->pdo       = $pdo;
        $this->companyId = $company_id;
        $this->method    = $method;
        $this->pinkey    = $pinkey;
        $this->iv        = $iv;
    }

    public function get(): ?array
    {
        $sth = $this->pdo->prepare(
            "SELECT
                server,
                port,
                username,
                from_name,
                from_email,
                encryption
             FROM company_smtp
             WHERE company_id = :company_id
             LIMIT 1"
        );
        $sth->execute([':company_id' => $this->companyId]);
        $row = $sth->fetch(PDO::FETCH_ASSOC);
        return $row ?: null;
    }

    public function save(array $data): void
    {
        $server     = trim((string)($data['smtp_host'] ?? ''));
        $port       = trim((string)($data['smtp_port'] ?? '587'));
        $username   = trim((string)($data['smtp_username'] ?? ''));
        $raw_pass   = (string)($data['smtp_password'] ?? '');
        $from_name  = trim((string)($data['smtp_from_name'] ?? ''));
        $from_email = trim((string)($data['smtp_from_email'] ?? ''));
        $encryption = trim((string)($data['smtp_encryption'] ?? 'tls'));

        if ($server === '' || $username === '') {
            throw new Exception('SMTP host and username are required.');
        }

        if (!in_array($port, ['25', '465', '587'], true)) $port = '587';
        if (!in_array($encryption, ['tls', 'ssl', 'none'], true)) $encryption = 'tls';

        $sth = $this->pdo->prepare(
            "SELECT smtp_id
             FROM company_smtp
             WHERE company_id = :company_id
             LIMIT 1"
        );
        $sth->execute([':company_id' => $this->companyId]);
        $existing_id = $sth->fetchColumn();

        if ($existing_id) {
            $this->update((int)$existing_id, $server, $port, $username, $raw_pass, $from_name, $from_email, $encryption);
            return;
        }

        if ($raw_pass === '') {
            throw new Exception('Password is required for a new SMTP configuration.');
        }

        $this->pdo->prepare(
            "INSERT INTO company_smtp
                (company_id, server, port, username, password,
                 from_name, from_email, encryption, updated_at)
             VALUES
                (:company_id, :server, :port, :username, :password,
                 :from_name, :from_email, :encryption, NOW())"
        )->execute([
            ':company_id' => $this->companyId,
            ':server'     => $server,
            ':port'       => $port,
            ':username'   => $username,
            ':password'   => $this->encryptPassword($raw_pass),
            ':from_name'  => $from_name,
            ':from_email' => $from_email,
            ':encryption' => $encryption,
        ]);
    }

    public function sendTest(string $to): void
    {
        $to = trim($to);
        if (!filter_var($to, FILTER_VALIDATE_EMAIL)) {
            throw new Exception('Invalid recipient email address.');
        }

        $sth = $this->pdo->prepare(
            "SELECT from_name
             FROM company_smtp
             WHERE company_id = :company_id
             LIMIT 1"
        );
        $sth->execute([':company_id' => $this->companyId]);
        $row = $sth->fetch(PDO::FETCH_ASSOC);

        if (!$row) {
            throw new Exception('No SMTP configuration found. Please save your settings first.');
        }

        $mailer = new mailer(['pdo1' => $this->pdo]);
        $mailer->send_email([
            'company_id'   => $this->companyId,
            'smtp'         => [],
            'to'           => $to,
            'subject'      => 'SMTP Test - WMS',
            'message'      => "This is a test email from your WMS SMTP configuration.\n\nIf you received this, your SMTP settings are working correctly.",
            'channel_name' => $row['from_name'] ?: 'WMS System',
            'key'          => $this->pinkey,
        ]);
    }

    private function update(int $smtp_id, string $server, string $port, string $username, string $raw_pass, string $from_name, string $from_email, string $encryption): void
    {
        if ($raw_pass !== '') {
            $this->pdo->prepare(
                "UPDATE company_smtp SET
                    server     = :server,
                    port       = :port,
                    username   = :username,
                    password   = :password,
                    from_name  = :from_name,
                    from_email = :from_email,
                    encryption = :encryption,
                    updated_at = NOW()
                 WHERE smtp_id = :smtp_id"
            )->execute([
                ':server'     => $server,
                ':port'       => $port,
                ':username'   => $username,
                ':password'   => $this->encryptPassword($raw_pass),
                ':from_name'  => $from_name,
                ':from_email' => $from_email,
                ':encryption' => $encryption,
                ':smtp_id'    => $smtp_id,
            ]);
            return;
        }

        $this->pdo->prepare(
            "UPDATE company_smtp SET
                server     = :server,
                port       = :port,
                username   = :username,
                from_name  = :from_name,
                from_email = :from_email,
                encryption = :encryption,
                updated_at = NOW()
             WHERE smtp_id = :smtp_id"
        )->execute([
            ':server'     => $server,
            ':port'       => $port,
            ':username'   => $username,
            ':from_name'  => $from_name,
            ':from_email' => $from_email,
            ':encryption' => $encryption,
            ':smtp_id'    => $smtp_id,
        ]);
    }

    private function encryptPassword(string $plain): string
    {
        return secret_encrypt($plain, $this->pinkey);
    }
}
?>