<?php

namespace App\Controllers;

use App\Core\Request;
use App\Core\Response;
use App\Core\Flows\ConversationFlowEngine;
use App\Services\TTSService;
use App\Models\WhatsAppSession;
use App\Models\CompanySubscription;
use App\Models\CompanySubscriptionUsage;

class OTPController extends BaseController
{
    /**
     * Send OTP verification code via WhatsApp (Text or Voice Note)
     * POST /api/otp/send
     */
    public function send(Request $request, Response $response): void
    {
        $companyId = $request->company_id;
        $body = $request->getBody();

        $phone = $body['phone'] ?? '';
        $type = $body['type'] ?? 'text'; // 'text' or 'voice'
        $sessionId = $body['session_id'] ?? null;
        $customCode = $body['code'] ?? null;

        if (empty($phone)) {
            $response->status(400)->json(['error' => 'Missing required parameter: phone']);
            return;
        }

        // Clean phone number (remove non-digits except +)
        $phone = preg_replace('/[^\d+]/', '', $phone);

        // 1. Resolve WhatsApp Session
        $session = null;
        if ($sessionId) {
            $session = WhatsAppSession::findSecure((int)$sessionId);
            if (!$session || (int)$session['company_id'] !== (int)$companyId) {
                $response->status(404)->json(['error' => 'WhatsApp session not found']);
                return;
            }
        } else {
            // Grab the first connected session of the company
            $sessions = WhatsAppSession::findAllByCompany($companyId);
            foreach ($sessions as $s) {
                if ($s['status'] === 'connected') {
                    $session = $s;
                    break;
                }
            }
            if (!$session && !empty($sessions)) {
                $session = $sessions[0]; // fallback to first session if none is connected
            }
        }

        if (!$session) {
            $response->status(400)->json(['error' => 'No active WhatsApp sessions configured for this company.']);
            return;
        }

        if ($session['status'] !== 'connected') {
            $response->status(400)->json(['error' => 'WhatsApp session is not connected. Connect the session first.']);
            return;
        }

        // 2. Check SaaS subscription quotas
        if ($companyId !== 1) {
            $activeSub = CompanySubscription::findActiveByCompany($companyId);
            if (!$activeSub) {
                $response->status(402)->json(['error' => 'Active subscription plan required.']);
                return;
            }

            if (!CompanySubscriptionUsage::hasRemainingLimit($companyId, 'request')) {
                $response->status(403)->json(['error' => 'Monthly request quota exceeded. Please upgrade your plan.']);
                return;
            }

            if ($type === 'voice') {
                if (!CompanySubscriptionUsage::hasRemainingLimit($companyId, 'voice')) {
                    $response->status(403)->json(['error' => 'Voice request quota exceeded. Please upgrade your plan.']);
                    return;
                }
                
                // Starter plan doesn't support Voice Notes
                $features = json_decode($activeSub['features'] ?: '{}', true);
                if (isset($features['voice']) && !$features['voice']) {
                    $response->status(403)->json(['error' => 'Voice OTP is not supported in your current subscription plan.']);
                    return;
                }
            }
        }

        // 3. Generate verification code
        $code = $customCode ? trim($customCode) : (string)rand(1000, 9999);

        // 4. Send Message
        try {
            if ($type === 'voice') {
                // Spacing the digits to force slow Arabic pronunciation: e.g. "1 2 3 4"
                $spacedCode = implode(' ', str_split($code));
                $textToRead = "رمز التحقق الخاص بك هو: {$spacedCode}. أكرر، رمز التحقق هو: {$spacedCode}.";
                
                $audioBase64 = TTSService::textToSpeechArabic($textToRead);
                if (!$audioBase64) {
                    $response->status(500)->json(['error' => 'Failed to generate voice OTP audio.']);
                    return;
                }

                // Send voice note
                ConversationFlowEngine::sendReply($session, $phone, '', null, $audioBase64, 'audio/mp3');
            } else {
                // Send text
                $textMsg = "رمز التحقق الخاص بك لمتجر نابه هو: *{$code}* \n الرجاء عدم مشاركته مع أي شخص.";
                ConversationFlowEngine::sendReply($session, $phone, $textMsg);
            }

            // Increment usage stats
            if ($companyId !== 1) {
                CompanySubscriptionUsage::incrementUsage($companyId, 'request');
                if ($type === 'voice') {
                    CompanySubscriptionUsage::incrementUsage($companyId, 'voice');
                }
            }

            $response->json([
                'status' => 'success',
                'message' => 'OTP sent successfully',
                'code' => $code,
                'type' => $type
            ]);

        } catch (\Exception $e) {
            error_log("[OTP Controller Error] " . $e->getMessage());
            $response->status(500)->json(['error' => 'Failed to send OTP message: ' . $e->getMessage()]);
        }
    }
}