<?php
/**
 * WEVIA NPS Submit · Opus 20avr · Doctrine #4 compliance
 * POST endpoint + internal function for WEVIA chat intent
 *
 * Usage:
 *   POST /api/wevia-nps-submit.php JSON {"respondent":"yacine","score":9,"comment":"..."}
 *   Returns: {"ok":true,"id":N,"nps_live":X}
 */
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');

function wevia_nps_classify($score) {
    if ($score >= 9) return 'promoter';
    if ($score >= 7) return 'passive';
    return 'detractor';
}

function wevia_nps_compute_live($db) {
    $sql = "SELECT 
        COUNT(*) AS total,
        COUNT(*) FILTER (WHERE score >= 9) AS promoters,
        COUNT(*) FILTER (WHERE score BETWEEN 7 AND 8) AS passives,
        COUNT(*) FILTER (WHERE score <= 6) AS detractors
    FROM admin.nps_responses";
    $row = $db->query($sql)->fetch(PDO::FETCH_ASSOC);
    $total = (int)($row['total'] ?? 0);
    if ($total === 0) return ['score' => null, 'total' => 0, 'status' => 'no_responses_yet'];
    $pct_promoters = $row['promoters'] / $total * 100;
    $pct_detractors = $row['detractors'] / $total * 100;
    $nps = round($pct_promoters - $pct_detractors, 1);
    return [
        'score' => $nps,
        'total' => $total,
        'promoters' => (int)$row['promoters'],
        'passives' => (int)$row['passives'],
        'detractors' => (int)$row['detractors'],
        'status' => 'live'
    ];
}

$method = $_SERVER['REQUEST_METHOD'] ?? 'GET';
$raw = file_get_contents('php://input');
$in = json_decode($raw, true) ?: $_POST;

try {
    $db = new PDO('pgsql:host=10.1.0.3;port=5432;dbname=adx_system;user=admin;password=admin123', null, null, [PDO::ATTR_TIMEOUT => 5, PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
} catch (Throwable $e) {
    echo json_encode(['ok' => false, 'error' => 'db: ' . $e->getMessage()]);
    exit;
}

if ($method === 'GET') {
    // Return live NPS state
    echo json_encode(['ok' => true, 'live' => wevia_nps_compute_live($db)], JSON_PRETTY_PRINT);
    exit;
}

// POST - submit new response
$respondent = trim((string)($in['respondent'] ?? 'anonymous'));
$score = isset($in['score']) ? (int)$in['score'] : -1;
$comment = trim((string)($in['comment'] ?? ''));

if ($score < 0 || $score > 10) {
    echo json_encode(['ok' => false, 'error' => 'score must be 0-10']);
    exit;
}

$category = wevia_nps_classify($score);

try {
    $stmt = $db->prepare("INSERT INTO admin.nps_responses (respondent, score, comment, category) VALUES (?, ?, ?, ?) RETURNING id");
    $stmt->execute([$respondent, $score, $comment, $category]);
    $id = (int)$stmt->fetchColumn();
    $live = wevia_nps_compute_live($db);
    echo json_encode([
        'ok' => true,
        'id' => $id,
        'respondent' => $respondent,
        'score' => $score,
        'category' => $category,
        'nps_live' => $live
    ], JSON_PRETTY_PRINT);
} catch (Throwable $e) {
    echo json_encode(['ok' => false, 'error' => $e->getMessage()]);
}