<?php
require_once 'db/config.php';

header('Content-Type: application/json');

$response = ['success' => false, 'message' => 'Invalid request'];

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $patient_id = $_POST['patient_id'] ?? null;
    $status = $_POST['status'] ?? null;
    $notes = $_POST['notes'] ?? null;
    $service_rendered = $_POST['service_rendered'] ?? null;
    $cost = $_POST['cost'] ?? null;

    if ($patient_id && $status) {
        try {
            $pdo = db();
            $sql = "UPDATE patients SET status = ?";
            $params = [$status];

            if ($notes !== null) {
                $sql .= ", notes = ?";
                $params[] = $notes;
            }

            if ($service_rendered !== null) {
                $sql .= ", service_rendered = ?";
                $params[] = $service_rendered;
            }

            if ($cost !== null) {
                $sql .= ", cost = ?";
                $params[] = $cost;
            }

            // When completing, set payment_status to unpaid
            if ($status === 'Completed') {
                $sql .= ", payment_status = 'unpaid'";
            }

            $sql .= " WHERE id = ?";
            $params[] = $patient_id;

            $stmt = $pdo->prepare($sql);
            
            if ($stmt->execute($params)) {
                $response['success'] = true;
                $response['message'] = 'Patient status updated successfully.';
                $response['status_class'] = get_status_badge_class($status);
            } else {
                $response['message'] = 'Failed to update patient status.';
            }
        } catch (PDOException $e) {
            $response['message'] = 'Database error: ' . $e->getMessage();
        }
    } else {
        $response['message'] = 'Missing patient ID or status.';
    }
}

echo json_encode($response);

function get_status_badge_class($status) {
    switch ($status) {
        case 'Pending':
            return 'warning';
        case 'In Progress':
            return 'info';
        case 'Completed':
            return 'success';
        default:
            return 'secondary';
    }
}
?>