<?php

namespace App\Services\SmsBilling;

use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

/**
 * SuperAdmin SMS wallet client (status / consume).
 *
 * Preferred: SUPERADMIN_SMS_BASE_URL + SUPERADMIN_SMS_SHARED_SECRET (+ optional DOMAIN)
 * Fallback: SUPERADMIN_REMOTE_TOKEN
 */
class SuperAdminSmsClient
{
    public function enabled(): bool
    {
        $base = trim((string) config('services.superadmin.sms_base_url', ''));
        if ($base === '') {
            return false;
        }

        return $this->sharedSecret() !== '' || $this->bearerToken() !== '';
    }

    /**
     * @return array{
     *   allowed: bool,
     *   blocked: bool,
     *   reason: ?string,
     *   balanceRials: int,
     *   pricePerPartRials: int,
     *   estimatedCostRials: int,
     *   balanceLevel: string
     * }|null
     */
    public function status(int $parts = 1, bool $isAlert = false): ?array
    {
        if (! $this->enabled()) {
            return null;
        }

        try {
            $path = '/api/remote/sms/status';
            $response = Http::withHeaders($this->authHeaders('GET', $path))
                ->acceptJson()
                ->timeout(4)
                ->get($this->url('status'), [
                    'parts' => max(1, $parts),
                    'isAlert' => $isAlert ? '1' : '0',
                ]);

            if (! $response->successful()) {
                Log::warning('SuperAdmin SMS status failed', [
                    'status' => $response->status(),
                    'body' => $response->body(),
                ]);

                return null;
            }

            $data = $response->json();
            if (! is_array($data)) {
                return null;
            }

            return [
                'allowed' => (bool) ($data['allowed'] ?? false),
                'blocked' => (bool) ($data['blocked'] ?? false),
                'reason' => isset($data['reason']) ? (string) $data['reason'] : null,
                'balanceRials' => (int) ($data['balanceRials'] ?? 0),
                'pricePerPartRials' => (int) ($data['pricePerPartRials'] ?? 0),
                'estimatedCostRials' => (int) ($data['estimatedCostRials'] ?? 0),
                'balanceLevel' => (string) ($data['balanceLevel'] ?? 'unknown'),
            ];
        } catch (\Throwable $e) {
            Log::warning('SuperAdmin SMS status exception', [
                'error' => $e->getMessage(),
            ]);

            return null;
        }
    }

    /**
     * @return array{ok: bool, balanceRials?: int, costRials?: int}|null
     */
    public function consume(
        string $receiver,
        string $body,
        int $parts,
        ?string $provider = null,
        ?string $source = null,
        bool $isAlert = false
    ): ?array {
        if (! $this->enabled()) {
            return null;
        }

        try {
            $path = '/api/remote/sms/consume';
            $payload = [
                'receiver' => $receiver,
                'body' => mb_substr($body, 0, 1000),
                'parts' => max(1, $parts),
                'provider' => $provider,
                'source' => $source,
                'isAlert' => $isAlert,
            ];
            $response = Http::withHeaders($this->authHeaders('POST', $path))
                ->acceptJson()
                ->timeout(6)
                ->post($this->url('consume'), $payload);

            if (! $response->successful()) {
                Log::error('SuperAdmin SMS consume failed', [
                    'status' => $response->status(),
                    'body' => $response->body(),
                ]);

                return null;
            }

            $data = $response->json();
            if (! is_array($data) || ! ($data['ok'] ?? false)) {
                return null;
            }

            return [
                'ok' => true,
                'balanceRials' => (int) ($data['balanceRials'] ?? 0),
                'costRials' => (int) ($data['costRials'] ?? 0),
            ];
        } catch (\Throwable $e) {
            Log::error('SuperAdmin SMS consume exception', [
                'error' => $e->getMessage(),
            ]);

            return null;
        }
    }

    /**
     * @return array<string, string>
     */
    private function authHeaders(string $method, string $canonicalPath): array
    {
        $secret = $this->sharedSecret();
        if ($secret !== '') {
            $domain = $this->domain();
            $timestamp = (string) time();
            $payload = $timestamp.'.'.strtoupper($method).'.'.$canonicalPath.'.'.$domain;
            $signature = hash_hmac('sha256', $payload, $secret);

            return [
                'X-Abshode-Domain' => $domain,
                'X-Abshode-Timestamp' => $timestamp,
                'X-Abshode-Signature' => $signature,
            ];
        }

        $token = $this->bearerToken();
        if ($token !== '') {
            return [
                'Authorization' => 'Bearer '.$token,
            ];
        }

        return [];
    }

    private function sharedSecret(): string
    {
        return trim((string) config('services.superadmin.sms_shared_secret', ''));
    }

    private function bearerToken(): string
    {
        return trim((string) config('services.superadmin.remote_token', ''));
    }

    private function domain(): string
    {
        $override = trim((string) config('services.superadmin.sms_domain', ''));
        if ($override !== '') {
            return $this->normalizeHost($override);
        }

        $fromApp = parse_url((string) config('app.url'), PHP_URL_HOST);

        return $this->normalizeHost(is_string($fromApp) ? $fromApp : '');
    }

    private function normalizeHost(string $value): string
    {
        $host = strtolower(trim($value));
        $host = preg_replace('#^https?://#', '', $host) ?? $host;
        $host = explode('/', $host)[0] ?? $host;
        $host = explode(':', $host)[0] ?? $host;

        return $host;
    }

    private function url(string $path): string
    {
        $base = rtrim((string) config('services.superadmin.sms_base_url', ''), '/');

        return $base.'/'.ltrim($path, '/');
    }
}