<?php

namespace App\Services\VoIP;

use App\Models\Setting;

class AmiProvider implements VoIPProviderInterface
{
    public function initiateCall(string $phone, ?string $callerId = null): array
    {
        $extension = trim((string) $callerId);
        if ($extension === '') {
            return [
                'success' => false,
                'provider_call_id' => null,
                'message' => 'شماره داخلی برای این کاربر ثبت نشده است.',
                'status' => 'missing_extension',
            ];
        }

        $config = $this->config();
        $missing = $this->missingConfig($config);
        if ($missing !== []) {
            return [
                'success' => false,
                'provider_call_id' => null,
                'message' => 'تنظیمات AMI کامل نیست.',
                'status' => 'configuration_error',
                'missing' => $missing,
            ];
        }

        $connection = $this->connect($config, $error);
        if (! $connection) {
            return [
                'success' => false,
                'provider_call_id' => null,
                'message' => $error ?: 'اتصال به مرکز تلفن برقرار نشد.',
                'status' => 'connection_failed',
            ];
        }

        $login = $this->login($connection, $config);
        if (! $this->isSuccess($login)) {
            fclose($connection);

            return [
                'success' => false,
                'provider_call_id' => null,
                'message' => $login['Message'] ?? 'ورود به AMI انجام نشد.',
                'status' => 'login_failed',
                'raw' => $login,
            ];
        }

        $providerCallId = 'ami_'.uniqid();
        $channel = "{$config['technology']}/{$extension}";
        $response = $this->sendAction($connection, [
            'Action' => 'Originate',
            'ActionID' => $providerCallId,
            'Channel' => $channel,
            'Context' => $config['context'],
            'Exten' => $phone,
            'Priority' => '1',
            'CallerID' => $this->callerId($extension),
            'Timeout' => (string) ((int) $config['originate_timeout'] * 1000),
            'Async' => 'true',
            'Variable' => "CRM_USER_EXTENSION={$extension}",
        ]);

        $this->logout($connection);
        fclose($connection);

        $ok = $this->isSuccess($response);

        return [
            'success' => $ok,
            'provider_call_id' => $providerCallId,
            'message' => $ok ? 'درخواست تماس به مرکز تلفن ارسال شد.' : ($response['Message'] ?? 'درخواست تماس به مرکز تلفن ارسال نشد.'),
            'status' => $ok ? 'initiated' : 'failed',
            'raw' => $response,
            'channel' => $channel,
        ];
    }

    public function getCallStatus(string $providerCallId): array
    {
        return [
            'status' => 'pending',
            'provider_call_id' => $providerCallId,
        ];
    }

    public function getRecordingUrl(string $providerCallId): ?string
    {
        $template = Setting::where('key', 'voip_ami_recording_url')->value('value');

        return $template ? str_replace('{id}', $providerCallId, $template) : null;
    }

    public function testConnection(): array
    {
        $config = $this->config();
        $missing = $this->missingConfig($config);
        if ($missing !== []) {
            return [
                'ok' => false,
                'message' => 'تنظیمات AMI کامل نیست.',
                'missing' => $missing,
            ];
        }

        $connection = $this->connect($config, $error);
        if (! $connection) {
            return [
                'ok' => false,
                'message' => $error ?: 'اتصال به AMI برقرار نشد.',
                'missing' => [],
            ];
        }

        $login = $this->login($connection, $config);
        $this->logout($connection);
        fclose($connection);

        return [
            'ok' => $this->isSuccess($login),
            'message' => $this->isSuccess($login) ? 'اتصال AMI موفق بود.' : ($login['Message'] ?? 'ورود به AMI انجام نشد.'),
            'missing' => [],
        ];
    }

    private function config(): array
    {
        return [
            'host' => trim((string) Setting::where('key', 'voip_ami_host')->value('value')),
            'port' => (int) (Setting::where('key', 'voip_ami_port')->value('value') ?: 5038),
            'username' => trim((string) Setting::where('key', 'voip_ami_username')->value('value')),
            'secret' => (string) Setting::where('key', 'voip_ami_secret')->value('value'),
            'technology' => trim((string) (Setting::where('key', 'voip_ami_channel_technology')->value('value') ?: 'SIP')),
            'context' => trim((string) (Setting::where('key', 'voip_ami_context')->value('value') ?: 'from-internal')),
            'timeout' => (float) (Setting::where('key', 'voip_ami_timeout')->value('value') ?: 5),
            'originate_timeout' => (int) (Setting::where('key', 'voip_ami_originate_timeout')->value('value') ?: 30),
        ];
    }

    private function missingConfig(array $config): array
    {
        return array_values(array_filter(['host', 'port', 'username', 'secret', 'technology', 'context'], fn (string $key) => empty($config[$key])));
    }

    private function connect(array $config, ?string &$error): mixed
    {
        $error = null;
        $connection = @stream_socket_client(
            "tcp://{$config['host']}:{$config['port']}",
            $errorCode,
            $errorMessage,
            $config['timeout']
        );

        if (! $connection) {
            $error = $errorMessage ?: "خطای اتصال AMI ({$errorCode})";

            return false;
        }

        stream_set_timeout($connection, (int) ceil($config['timeout']));
        fgets($connection);

        return $connection;
    }

    private function login(mixed $connection, array $config): array
    {
        return $this->sendAction($connection, [
            'Action' => 'Login',
            'Username' => $config['username'],
            'Secret' => $config['secret'],
            'Events' => 'off',
        ]);
    }

    private function logout(mixed $connection): void
    {
        $this->sendAction($connection, ['Action' => 'Logoff']);
    }

    private function sendAction(mixed $connection, array $headers): array
    {
        foreach ($headers as $key => $value) {
            fwrite($connection, "{$key}: {$value}\r\n");
        }
        fwrite($connection, "\r\n");

        return $this->readResponse($connection);
    }

    private function readResponse(mixed $connection): array
    {
        $response = [];
        while (! feof($connection)) {
            $line = fgets($connection);
            if ($line === false || trim($line) === '') {
                break;
            }
            if (str_contains($line, ':')) {
                [$key, $value] = explode(':', $line, 2);
                $response[trim($key)] = trim($value);
            }
        }

        return $response;
    }

    private function isSuccess(array $response): bool
    {
        return strtolower((string) ($response['Response'] ?? '')) === 'success';
    }

    private function callerId(string $extension): string
    {
        $template = Setting::where('key', 'voip_ami_caller_id_template')->value('value') ?: 'CRM <{extension}>';

        return str_replace('{extension}', $extension, $template);
    }
}