// ==========================
// 3. Manual Fetch Function (Updated)
// ==========================
function serpapi_run_each_keyword_manual() {

    $serpapi_key = get_option('serpapi_api_key');
    $openai_key = get_option('serpapi_openai_api_key');
    $recipient_emails = get_option('serpapi_recipient_emails');
    $max_urls = intval(get_option('serpapi_max_urls', 5000));
    $max_posts_per_keyword = 10; // limit posts per keyword
    $keywords = array_map('trim', explode(',', get_option('serpapi_keywords', '')));

    if (!$serpapi_key || !$recipient_emails || empty($keywords)) return;

    $emailed_urls = get_option('serpapi_emailed_urls', []);

    // Split recipients
    $recipients = array_map('trim', explode(',', $recipient_emails));

    foreach ($keywords as $keyword) {
        $results_data = serpapi_search_keyword_manual($keyword, $emailed_urls, $serpapi_key, $openai_key, $max_posts_per_keyword);

        if (!empty(trim($results_data['results']))) {
            $subject = ucfirst($keyword) . " Construction News";
            $headers = ['Content-Type: text/plain; charset=UTF-8'];

            foreach ($recipients as $email) {
                if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
                    wp_mail($email, $subject, $results_data['results'], $headers);
                }
            }
        }

        $emailed_urls = $results_data['emailed_urls'];
    }

    // Trim stored URLs to max limit
    $emailed_urls = array_slice($emailed_urls, -$max_urls);
    update_option('serpapi_emailed_urls', $emailed_urls);
}

// ==========================
// 4. Fetch and Filter Articles (Updated)
// ==========================
function serpapi_search_keyword_manual($keyword, $emailed_urls, $serpapi_key, $openai_key, $max_posts = 10) {

    $query = sanitize_text_field($keyword) . " construction project";
    $url = "https://serpapi.com/search?engine=google_news&q=" . urlencode($query) . "&tbs=qdr:d&hl=en&api_key=" . $serpapi_key;

    $response = wp_remote_get($url);
    if (is_wp_error($response)) return ['results'=>'','emailed_urls'=>$emailed_urls];

    $data = json_decode(wp_remote_retrieve_body($response), true);
    if (!isset($data['news_results'])) return ['results'=>'','emailed_urls'=>$emailed_urls];

    $cutoff = strtotime('-24 hours');
    $results = "";
    $count = 0;

    foreach ($data['news_results'] as $article) {
        if ($count >= $max_posts) break; // stop after max_posts

        if (!isset($article['title']) || !isset($article['link'])) continue;

        $title = sanitize_text_field($article['title']);
        $link = esc_url_raw($article['link']);

        if (in_array($link, $emailed_urls)) continue;

        // Check published date
        $published_str = $article['date'] ?? '';
        $published_time = strtotime($published_str);
        if ($published_time && $published_time < $cutoff) continue;

        // OpenAI filtering: relevance + real project
        if ($openai_key) {
            $prompt = "
Determine if this news article is a REAL construction project update published in the last 24 hours. 
Return ONLY 'YES' or 'NO'.

Title: $title
URL: $link

Return YES only if:
- It is a real construction project (solar, wind, data center, airport, rail, stadium, mall, housing, etc.)
- AND it includes a milestone such as: groundbreaking, approval, planning, funding, contract award, construction start, expansion, commissioning, completion.

Return NO if:
- It is corporate news, political news, general business, opinion, policy, or non-project content.
";
            $is_project = serpapi_filter_with_openai_prompt($prompt, $openai_key);
            if (!$is_project) continue;
        }

        $results .= "$title\n$link\n\n";
        $emailed_urls[] = $link;
        $count++;
    }

    return ['results'=>$results,'emailed_urls'=>$emailed_urls];
}

// ==========================
// 5. OpenAI Project Filter (Updated)
// ==========================
function serpapi_filter_with_openai_prompt($prompt, $api_key) {

    $response = wp_remote_post('https://api.openai.com/v1/chat/completions', [
        'headers' => [
            'Content-Type' => 'application/json',
            'Authorization' => 'Bearer ' . $api_key,
        ],
        'body' => json_encode([
            'model' => 'gpt-4o-mini',
            'messages' => [
                ['role'=>'user','content'=>$prompt]
            ],
            'temperature'=>0,
            'max_tokens'=>5
        ])
    ]);

    if (is_wp_error($response)) return false;

    $data = json_decode(wp_remote_retrieve_body($response), true);

    if (!isset($data['choices'][0]['message']['content'])) return false;

    return strtoupper(trim($data['choices'][0]['message']['content'])) === 'YES';
}