notification_helper.php

<?php
// Notification helper functions

/**
 * Create a notification in the database
 * @param mysqli $conn Database connection
 * @param int|null $uid User ID (null for expert notifications)
 * @param int|null $eid Expert ID (null for user notifications)
 * @param string $type Notification type
 * @param string $description Notification description
 * @param bool $isPersonal Whether notification is personal (true) or global (false)
 * @return bool Success status
 */
function createNotification($conn, $uid = null, $eid = null, $type, $description, $isPersonal = true) {
    $sql = "INSERT INTO notification (uid, eid, type, description, is_personal) VALUES (?, ?, ?, ?, ?)";
    $stmt = $conn->prepare($sql);
    
    if ($stmt) {
        $stmt->bind_param("iissi", $uid, $eid, $type, $description, $isPersonal);
        $result = $stmt->execute();
        $stmt->close();
        return $result;
    }
    
    return false;
}

/**
 * Create notification for new blog post
 * @param mysqli $conn Database connection
 * @param string $authorName Blog author name
 * @param string $blogTitle Blog title
 * @param int $authorId Author's user ID (to exclude from notifications)
 */
function notifyNewBlog($conn, $authorName, $blogTitle, $authorId) {
    // Global notification - goes to everyone, no specific uid/eid
    $description = "New blog posted: \"$blogTitle\" by $authorName.";
    createNotification($conn, null, null, 'new_blog', $description, false);
}

/**
 * Create notification for blog like
 * @param mysqli $conn Database connection
 * @param int $blogAuthorId Blog author's user ID
 * @param string $likerName Name of person who liked
 * @param string $blogTitle Blog title
 * @param bool $isExpertBlog Whether the blog was created by an expert
 */
function notifyBlogLike($conn, $blogAuthorId, $likerName, $blogTitle, $isExpertBlog = false) {
    $description = "Your blog \"$blogTitle\" has been liked by $likerName.";
    
    if ($isExpertBlog) {
        // Expert blog - notify expert author
        createNotification($conn, null, $blogAuthorId, 'blog_like', $description, true);
    } else {
        // User blog - notify user author
        createNotification($conn, $blogAuthorId, null, 'blog_like', $description, true);
    }
}

/**
 * Create notification for blog comment
 * @param mysqli $conn Database connection
 * @param int $blogAuthorId Blog author's user ID
 * @param string $commenterName Name of person who commented
 * @param string $blogTitle Blog title
 * @param bool $isExpertBlog Whether the blog was created by an expert
 */
function notifyBlogComment($conn, $blogAuthorId, $commenterName, $blogTitle, $isExpertBlog = false) {
    $description = "Your blog \"$blogTitle\" has a new comment from $commenterName.";
    
    if ($isExpertBlog) {
        // Expert blog - notify expert author
        createNotification($conn, null, $blogAuthorId, 'blog_comment', $description, true);
    } else {
        // User blog - notify user author
        createNotification($conn, $blogAuthorId, null, 'blog_comment', $description, true);
    }
}

/**
 * Create notification for new course enrollment
 * @param mysqli $conn Database connection
 * @param int $courseId Course ID
 * @param string $newMemberName Name of new member
 * @param string $courseName Course name
 * @param int $newMemberId New member's ID (to exclude from notifications)
 */
function notifyCourseNewMember($conn, $courseId, $newMemberName, $courseName, $newMemberId) {
    $description = "$newMemberName has joined the course \"$courseName\" that you are taking.";
    
    // Notify the expert instructor
    $expertSql = "SELECT eid FROM course WHERE cid = ?";
    $expertStmt = $conn->prepare($expertSql);
    
    if ($expertStmt) {
        $expertStmt->bind_param("i", $courseId);
        $expertStmt->execute();
        $expertResult = $expertStmt->get_result();
        
        if ($expertRow = $expertResult->fetch_assoc()) {
            // Create notification for the expert
            createNotification($conn, null, $expertRow['eid'], 'course_new_member', $description, true);
        }
        
        $expertStmt->close();
    }
    
    // Notify all enrolled users except the new member
    $userSql = "SELECT DISTINCT uid FROM enrollment WHERE cid = ? AND uid != ?";
    $userStmt = $conn->prepare($userSql);
    
    if ($userStmt) {
        $userStmt->bind_param("ii", $courseId, $newMemberId);
        $userStmt->execute();
        $userResult = $userStmt->get_result();
        
        while ($userRow = $userResult->fetch_assoc()) {
            // Create notification for each enrolled user
            createNotification($conn, $userRow['uid'], null, 'course_new_member', $description, true);
        }
        
        $userStmt->close();
    }
}

/**
 * Create notification for course feedback
 * @param mysqli $conn Database connection
 * @param int $courseId Course ID
 * @param string $feedbackGiverName Name of feedback giver
 * @param string $courseName Course name
 * @param int $feedbackGiverId Feedback giver's ID (to exclude from notifications)
 */
function notifyCourseFeedback($conn, $courseId, $feedbackGiverName, $courseName, $feedbackGiverId) {
    $description = "$feedbackGiverName has given feedback on the course \"$courseName\" that you are taking.";
    
    // Notify the expert instructor
    $expertSql = "SELECT eid FROM course WHERE cid = ?";
    $expertStmt = $conn->prepare($expertSql);
    
    if ($expertStmt) {
        $expertStmt->bind_param("i", $courseId);
        $expertStmt->execute();
        $expertResult = $expertStmt->get_result();
        
        if ($expertRow = $expertResult->fetch_assoc()) {
            // Create notification for the expert
            createNotification($conn, null, $expertRow['eid'], 'course_feedback', $description, true);
        }
        
        $expertStmt->close();
    }
    
    // Notify all enrolled users except the feedback giver
    $userSql = "SELECT DISTINCT uid FROM enrollment WHERE cid = ? AND uid != ?";
    $userStmt = $conn->prepare($userSql);
    
    if ($userStmt) {
        $userStmt->bind_param("ii", $courseId, $feedbackGiverId);
        $userStmt->execute();
        $userResult = $userStmt->get_result();
        
        while ($userRow = $userResult->fetch_assoc()) {
            // Create notification for each enrolled user
            createNotification($conn, $userRow['uid'], null, 'course_feedback', $description, true);
        }
        
        $userStmt->close();
    }
}

/**
 * Create notification for new appointment
 * @param mysqli $conn Database connection
 * @param int $expertId Expert ID
 * @param int $userId User ID who booked the appointment
 * @param string $userName User name
 * @param string $appointmentDate Appointment date
 * @param string $appointmentTime Appointment time
 */
function notifyNewAppointment($conn, $expertId, $userId, $userName, $appointmentDate, $appointmentTime) {
    $formattedDate = date('l, F j, Y', strtotime($appointmentDate));
    $formattedTime = date('g:i A', strtotime($appointmentTime));
    
    // Personal notification - shows only to the expert (with both uid and eid for context)
    $description = "$userName has booked an appointment with you on $formattedDate at $formattedTime.";
    createNotification($conn, $userId, $expertId, 'appointment_new', $description, true);
}

/**
 * Create notification for appointment status change
 * @param mysqli $conn Database connection
 * @param int $userId User ID
 * @param int $expertId Expert ID who made the status change
 * @param string $expertName Expert name
 * @param string $status New status (accepted/declined)
 * @param string $appointmentDate Appointment date
 * @param string $appointmentTime Appointment time
 */
function notifyAppointmentStatusChange($conn, $userId, $expertId, $expertName, $status, $appointmentDate, $appointmentTime) {
    $formattedDate = date('l, F j, Y', strtotime($appointmentDate));
    $formattedTime = date('g:i A', strtotime($appointmentTime));
    
    // Personal notification - shows only to the patient (with both uid and eid for context)
    if ($status === 'accepted') {
        $description = "Your appointment with $expertName on $formattedDate at $formattedTime has been accepted.";
        $type = 'appointment_accepted';
    } else {
        $description = "Your appointment with $expertName on $formattedDate at $formattedTime has been declined.";
        $type = 'appointment_declined';
    }
    
    createNotification($conn, $userId, $expertId, $type, $description, true);
}
?>