#!/bin/bash

# Format the k3s disk if not already formatted

# This command creates an ext4 filesystem on the specified 
# disk with no reserved space for root, forces the operation, 
# fully initializes inode tables and the journal, and enables 
# discard/TRIM for better performance on SSDs or 
# thin-provisioned storage.
if ! lsblk | grep -q "/mnt/disks/k3s"; then
    mkfs.ext4 -m 0 -F -E lazy_itable_init=0,lazy_journal_init=0,discard /dev/disk/by-id/google-k3s-disk
    mkdir -p /var/lib/rancher/k3s
    mount -o discard,defaults /dev/disk/by-id/google-k3s-disk /var/lib/rancher/k3s
    chmod a+w /var/lib/rancher/k3s
fi
# A disk named k3s-disk in your Terraform configuration will
# appear as /dev/disk/by-id/google-k3s-disk.

# Format the app-data-disk if not already formatted
if ! lsblk | grep -q "/mnt/disks/app-data"; then
    mkfs.ext4 -m 0 -F -E lazy_itable_init=0,lazy_journal_init=0,discard /dev/disk/by-id/google-app-data-disk
    mkdir -p /mnt/disks/app-data
    mount -o discard,defaults /dev/disk/by-id/google-app-data-disk /mnt/disks/app-data
    chmod a+w /mnt/disks/app-data
fi
# Similarly, a disk named app-data-disk will appear as /dev/
# disk/by-id/google-app-data-disk.



# ensure only run once
if [[ -f /etc/startup_was_launched ]]; then exit 0; fi
touch /etc/startup_was_launched

# apt install
apt update
apt install -y ncdu htop

# helm install
curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3
chmod 700 get_helm.sh
/bin/bash get_helm.sh

# user bashrc config
rc=/home/user/.bashrc
{
    echo "export KUBECONFIG=~/.kube/config"
    echo "alias l='ls -lah'"
    echo "alias ll='ls -lh'"
    echo "alias k=kubectl"
    echo "export dry='--dry-run=client'"
    echo "export o='-oyaml'"
    echo "alias kcd='kubectl config use-context'"
    echo "source <(kubectl completion bash)"
    echo "complete -F __start_kubectl k"
    echo "alias k='kubectl'"
} >> $rc


# Install k3s and configure it to use the persistent disk for data storage
# curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--data-dir /mnt/disks/k3s" sh -

k3s_version="v1.32.8+k3s1"
curl -sfL https://get.k3s.io \
| \
    INSTALL_K3S_VERSION="$k3s_version" sh -s - server \
    --cluster-init \
    --disable traefik \
    --disable servicelb 


mkdir -p /home/user/.kube
chown user:user /home/user/.kube
chmod 700 /home/user/.kube
# Copy the kubeconfig file to the user's home directory 
# for easier access
cp /etc/rancher/k3s/k3s.yaml /home/user/.kube/config
chown user:user /home/user/.kube/config