#!/bin/bash
# Script to fix cgroup configuration for container runtime in Alpine Linux

echo "🔧 Fixing cgroup configuration for container runtime..."

# Check if running as root
if [ "$(id -u)" -ne 0 ]; then
    echo "❌ This script must be run as root"
    exit 1
fi

# Update package lists
echo "📦 Updating package lists..."
apk update

# Install necessary packages for cgroup management
echo "📦 Installing cgroup-related packages..."
apk add cgroup-tools cgroupfs-mount

# Create cgroup mount points
echo "🔧 Creating cgroup mount points..."
mkdir -p /sys/fs/cgroup/{cpu,cpuacct,memory,devices,freezer,net_cls,blkio,cpuset,perf_event,pids}

# Mount cgroup filesystems
echo "🔧 Mounting cgroup filesystems..."
mount -t cgroup cgroup /sys/fs/cgroup
mount -t cgroup cgroup /sys/fs/cgroup/cpu
mount -t cgroup cgroup /sys/fs/cgroup/cpuacct
mount -t cgroup cgroup /sys/fs/cgroup/memory
mount -t cgroup cgroup /sys/fs/cgroup/devices
mount -t cgroup cgroup /sys/fs/cgroup/freezer
mount -t cgroup cgroup /sys/fs/cgroup/net_cls
mount -t cgroup cgroup /sys/fs/cgroup/blkio
mount -t cgroup cgroup /sys/fs/cgroup/cpuset
mount -t cgroup cgroup /sys/fs/cgroup/perf_event
mount -t cgroup cgroup /sys/fs/cgroup/pids

# Add cgroup mounts to /etc/fstab for persistence
echo "💾 Adding cgroup mounts to /etc/fstab..."
cat >> /etc/fstab << EOF
# Cgroup mounts for container runtime
cgroup /sys/fs/cgroup cgroup defaults 0 0
cgroup /sys/fs/cgroup/cpu cgroup defaults 0 0
cgroup /sys/fs/cgroup/cpuacct cgroup defaults 0 0
cgroup /sys/fs/cgroup/memory cgroup defaults 0 0
cgroup /sys/fs/cgroup/devices cgroup defaults 0 0
cgroup /sys/fs/cgroup/freezer cgroup defaults 0 0
cgroup /sys/fs/cgroup/net_cls cgroup defaults 0 0
cgroup /sys/fs/cgroup/blkio cgroup defaults 0 0
cgroup /sys/fs/cgroup/cpuset cgroup defaults 0 0
cgroup /sys/fs/cgroup/perf_event cgroup defaults 0 0
cgroup /sys/fs/cgroup/pids cgroup defaults 0 0
EOF

# Enable and start cgroup service if available
if [ -f /etc/init.d/cgroups ]; then
    echo "🚀 Enabling and starting cgroups service..."
    rc-update add cgroups boot
    rc-service cgroups start
fi

# Create a script to set up cgroups on boot
echo "🔧 Creating cgroup setup script..."
cat > /usr/local/bin/setup-cgroups.sh << 'EOF'
#!/bin/bash
# Script to set up cgroups on boot

# Mount cgroup filesystems if not already mounted
if ! mountpoint -q /sys/fs/cgroup; then
    mount -t cgroup cgroup /sys/fs/cgroup
fi

# Ensure all cgroup subsystems are mounted
for subsystem in cpu cpuacct memory devices freezer net_cls blkio cpuset perf_event pids; do
    if [ ! -d "/sys/fs/cgroup/$subsystem" ]; then
        mkdir -p "/sys/fs/cgroup/$subsystem"
    fi
    if ! mountpoint -q "/sys/fs/cgroup/$subsystem"; then
        mount -t cgroup cgroup "/sys/fs/cgroup/$subsystem"
    fi
done
EOF

chmod +x /usr/local/bin/setup-cgroups.sh

# Add the script to local.d to run on boot
echo "🚀 Adding cgroup setup script to boot sequence..."
mkdir -p /etc/local.d
echo "/usr/local/bin/setup-cgroups.sh" > /etc/local.d/cgroups.start
chmod +x /etc/local.d/cgroups.start

# Enable local.d service
rc-update add local default

# Verify cgroup setup
echo "✅ Verifying cgroup setup..."
if mountpoint -q /sys/fs/cgroup; then
    echo "✅ Cgroup filesystem is mounted"
else
    echo "❌ Cgroup filesystem is not mounted"
fi

# Check if pids subsystem is available
if [ -d /sys/fs/cgroup/pids ]; then
    echo "✅ PIDS cgroup subsystem is available"
else
    echo "❌ PIDS cgroup subsystem is not available"
fi

echo "🎉 Cgroup configuration complete!"
echo "🔄 Please reboot the system to ensure all changes take effect"
echo "After reboot, you should be able to run your container successfully."