<?php
/**
 * Ethica WhatsApp API — Meta Business API Gateway
 * P0-3: Ready to activate with Meta WhatsApp Business credentials
 */
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');

$TOKEN = 'ETHICA_API_2026_SECURE';
if (($_GET['token'] ?? $_POST['token'] ?? '') !== $TOKEN) { echo json_encode(['error'=>'Unauthorized']); exit; }

$pdo = new PDO("pgsql:host=10.1.0.3;port=5432;dbname=adx_system", "admin", "admin123");
$pdo->exec("SET search_path TO ethica, public");
$pdo->exec("CREATE TABLE IF NOT EXISTS whatsapp_providers (id SERIAL PRIMARY KEY, name TEXT, phone_number_id TEXT, access_token TEXT, business_id TEXT, verify_token TEXT, active BOOLEAN DEFAULT false, created_at TIMESTAMP DEFAULT NOW())");
$pdo->exec("CREATE TABLE IF NOT EXISTS whatsapp_log (id SERIAL PRIMARY KEY, campaign_id INT, phone TEXT, template_name TEXT, status TEXT DEFAULT 'pending', wa_message_id TEXT, sent_at TIMESTAMP DEFAULT NOW())");

$action = $_POST['action'] ?? $_GET['action'] ?? 'status';

if ($action === 'status') {
    $providers = $pdo->query("SELECT id, name, phone_number_id, active FROM whatsapp_providers")->fetchAll(PDO::FETCH_ASSOC);
    $sent = $pdo->query("SELECT COUNT(*) FROM whatsapp_log WHERE status='sent'")->fetchColumn();
    echo json_encode(['ok'=>true, 'providers'=>$providers, 'total_sent'=>(int)$sent]);
}
elseif ($action === 'add_provider') {
    $stmt = $pdo->prepare("INSERT INTO whatsapp_providers (name, phone_number_id, access_token, business_id, verify_token, active) VALUES (?,?,?,?,?,true)");
    $stmt->execute([$_POST['name']??'Meta WA', $_POST['phone_number_id']??'', $_POST['access_token']??'', $_POST['business_id']??'', $_POST['verify_token']??bin2hex(random_bytes(16))]);
    echo json_encode(['ok'=>true, 'message'=>'WhatsApp provider added']);
}
elseif ($action === 'send_template') {
    $phone = $_POST['phone'] ?? '';
    $template = $_POST['template_name'] ?? 'ethica_consent';
    $params = json_decode($_POST['params'] ?? '[]', true) ?: [];
    
    $prov = $pdo->query("SELECT * FROM whatsapp_providers WHERE active=true LIMIT 1")->fetch(PDO::FETCH_ASSOC);
    if (!$prov) { echo json_encode(['error'=>'No active WhatsApp provider']); exit; }
    
    $body = ['messaging_product'=>'whatsapp','to'=>$phone,'type'=>'template','template'=>['name'=>$template,'language'=>['code'=>'fr'],'components'=>[]]];
    if ($params) {
        $body['template']['components'][] = ['type'=>'body','parameters'=>array_map(fn($v)=>['type'=>'text','text'=>$v], $params)];
    }
    
    $ch = curl_init("https://graph.facebook.com/v18.0/{$prov['phone_number_id']}/messages");
    curl_setopt_array($ch, [CURLOPT_POST=>true, CURLOPT_RETURNTRANSFER=>true, CURLOPT_TIMEOUT=>15,
        CURLOPT_HTTPHEADER=>["Content-Type: application/json","Authorization: Bearer {$prov['access_token']}"],
        CURLOPT_POSTFIELDS=>json_encode($body)]);
    $r = curl_exec($ch); $code = curl_getinfo($ch, CURLINFO_HTTP_CODE); curl_close($ch);
    $d = json_decode($r, true);
    
    $waId = $d['messages'][0]['id'] ?? '';
    $pdo->prepare("INSERT INTO whatsapp_log (phone, template_name, status, wa_message_id) VALUES (?,?,?,?)")
        ->execute([$phone, $template, $code==200?'sent':'failed', $waId]);
    
    echo json_encode(['ok'=>$code==200, 'wa_message_id'=>$waId, 'response'=>$d]);
}
elseif ($action === 'webhook') {
    // Meta webhook verification
    if ($_SERVER['REQUEST_METHOD'] === 'GET') {
        $mode = $_GET['hub_mode'] ?? '';
        $token = $_GET['hub_verify_token'] ?? '';
        $challenge = $_GET['hub_challenge'] ?? '';
        $prov = $pdo->query("SELECT verify_token FROM whatsapp_providers WHERE active=true LIMIT 1")->fetch(PDO::FETCH_ASSOC);
        if ($mode === 'subscribe' && $token === ($prov['verify_token']??'')) { echo $challenge; } else { http_response_code(403); }
        exit;
    }
    // Incoming message webhook
    $payload = json_decode(file_get_contents('php://input'), true);
    file_put_contents("/tmp/wa_webhook_".time().".json", json_encode($payload));
    echo json_encode(['ok'=>true]);
}
else {
    echo json_encode(['actions'=>['status','add_provider','send_template','webhook']]);
}