#!/bin/bash
: '
 @vendor    Chorke Academia, Inc.
 @web       https://cdn.chorke.org/docs/academia
 @version   1.0.00
 @since     1.0.00
'

:<<EXE
if [ -x "$(command -v curl)" ];then \
sudo apt -qq update;\
export MINIKUBE_CPU_USE=2;\
export MINIKUBE_RAM_USE=5900;\
bash <(curl -s 'https://cdn.chorke.org/exec/cli/bash/install/minikube/1.0.0-ubuntu-22.04.sh.txt');\
else printf 'curl \033[0;31mnot found! \033[0m:(\n';fi
EXE


:<<EXE
if [ -x "$(command -v curl)" ];then \
sudo apt -qq update;\
export MINIKUBE_CPU_USE=8;\
export MINIKUBE_RAM_USE=16384;\
bash <(curl -s 'https://cdn.chorke.org/exec/cli/bash/install/minikube/1.0.0-ubuntu-22.04.sh.txt');\
else printf 'curl \033[0;31mnot found! \033[0m:(\n';fi
EXE


export SYSTEM_CPU_LIMIT=$(getconf _NPROCESSORS_ONLN)
export SYSTEM_RAM_LIMIT=$(awk '/^MemTotal:/ { print int($2/1024); }' /proc/meminfo)


function errors_exit(){
  exit 1
}


function validate(){
    # check existence of wget
    if [ ! -x "$(command -v wget)" ];then
        printf 'wget \033[0;31mnot found! \033[0m:(\n'; errors_exit
    fi

    # resolve minikube user home if not setted
    if [[ "${MINIKUBE_USER_HOME}/env/set" == '/env/set' ]];then
        export MINIKUBE_USER_HOME='/home/minikube'
    fi

    # resolve minikube home if not setted
    if [[ "${MINIKUBE_HOME_DIR}/env/set" == '/env/set' ]];then
        export MINIKUBE_HOME_DIR=/var/minikube
    fi

    if [[ "${MINIKUBE_CPU_USE}/env/set" != '/env/set' ]]&&
       [[ ${MINIKUBE_CPU_USE} =~ ^[0-9]+$ ]]&&[[ ${MINIKUBE_CPU_USE} -ge 2 ]]; then
        if [[ ${MINIKUBE_CPU_USE} -lt ${SYSTEM_CPU_LIMIT} ]];then export MINIKUBE_OPTS="--cpus ${MINIKUBE_CPU_USE}"
        else printf 'SYSTEM_CPU_LIMIT \033[0;31m exceeded! \033[0m:(\n';errors_exit; fi
    else
        export MINIKUBE_CPU_USE=2
        export MINIKUBE_OPTS="--cpus ${MINIKUBE_CPU_USE}"
    fi


    if [[ "${MINIKUBE_RAM_USE}/env/set" != '/env/set' ]]&&
       [[ ${MINIKUBE_RAM_USE} =~ ^[0-9]+$ ]]&& [[ ${MINIKUBE_RAM_USE} -ge 8192 ]]; then
        if [[ ${MINIKUBE_RAM_USE} -lt ${SYSTEM_RAM_LIMIT} ]];then
            if [[ "${MINIKUBE_OPTS}/env/set" == '/env/set' ]];then export MINIKUBE_OPTS="--memory ${MINIKUBE_RAM_USE}"
            else export MINIKUBE_OPTS="${MINIKUBE_OPTS} --memory ${MINIKUBE_RAM_USE}"; fi
        else printf 'SYSTEM_RAM_LIMIT \033[0;31m exceeded! \033[0m:(\n';errors_exit; fi
    else
        export MINIKUBE_RAM_USE=5900
        if [[ "${MINIKUBE_OPTS}/env/set" == '/env/set' ]];then export MINIKUBE_OPTS="--memory ${MINIKUBE_RAM_USE}"
        else export MINIKUBE_OPTS="${MINIKUBE_OPTS} --memory ${MINIKUBE_RAM_USE}"; fi
    fi

    # resovle and check minikube base from it's home
    export MINIKUBE_BASE="$(dirname "${MINIKUBE_HOME_DIR}")"
    if [ "${MINIKUBE_BASE}" == '.' ];then
        printf 'MINIKUBE_BASE \033[0;31mpath is invalid \033[0m:)\n';errors_exit
    fi

    # check existence of minikube
    if [ -d "${MINIKUBE_HOME_DIR}" ];then
        if [ "$(ls -A "${MINIKUBE_HOME_DIR}")" ];then
            printf 'MINIKUBE_HOME \033[0;31malready exists \033[0m:)\n';errors_exit
        else rm -rf "${MINIKUBE_HOME_DIR}";fi
    fi

    # check existence of minikube.service
    if [ -f '/etc/systemd/system/minikube.service' ];then
        printf 'minikube.service     \033[0;31malready installed \033[0m:)\n';errors_exit
    fi
}

function download(){
    if [ ! -d "${MINIKUBE_HOME_DIR}" ];then
        sudo mkdir -p ${MINIKUBE_HOME_DIR}/{bin,etc}
        sudo wget -cq https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 -O ${MINIKUBE_HOME_DIR}/bin/minikube
        sudo update-alternatives --install /usr/local/bin/minikube minikube ${MINIKUBE_HOME_DIR}/bin/minikube 1983
        sudo chmod +x ${MINIKUBE_HOME_DIR}/bin/minikube
    fi
}

function approve(){
    if ! sudo id -g minikube &>/dev/null;then sudo addgroup --quiet --system minikube;fi
    if ! sudo id -u minikube &>/dev/null;then
        sudo adduser --quiet --system --home ${MINIKUBE_USER_HOME} --shell '/bin/bash' --ingroup minikube --disabled-password minikube
    fi

    sudo chown    -R minikube:minikube ${MINIKUBE_HOME_DIR}
    sudo usermod -aG minikube ${USER}
    sudo usermod -aG docker minikube
    sudo usermod -aG minikube root
}

function setting(){
    sudo -i -u minikube bash << EXE
# format minikube config path
mkdir -p ${MINIKUBE_USER_HOME}/.minikube
EXE
}   

function install(){
    cat << ENV | sudo tee /etc/default/minikube >/dev/null
MINIKUBE_OPTS="${MINIKUBE_OPTS}"
MINIKUBE_CONF_ENV=/etc/default/minikube
MINIKUBE_CONF_DIR="${MINIKUBE_USER_HOME}/.minikube"
ENV

    sudo chown -R minikube:minikube ${MINIKUBE_HOME_DIR}
    cat << SYS | sudo tee /etc/systemd/system/minikube.service >/dev/null
[Unit]
Description=Minikube Cluster
Documentation=https://minikube.sigs.k8s.io/docs/
After=network-online.target containerd.service docker.service
Requires=network-online.target containerd.service docker.service
Wants=network-online.target docker.service
AssertFileIsExecutable=${MINIKUBE_HOME_DIR}/bin/minikube

[Service]
Type=forking
User=minikube
Group=minikube
RemainAfterExit=yes
ProtectProc=invisible
StandardOutput=journal
WorkingDirectory=${MINIKUBE_HOME_DIR}

EnvironmentFile=-/etc/default/minikube 
ExecStartPre=/bin/bash -c "if [ -z \"\${MINIKUBE_OPTS}\" ]; then echo \"Variable MINIKUBE_OPTS not set in /etc/default/minikube\"; errors_exit; fi"
ExecStartPost=/bin/bash -c "echo \${MAINPID} > ${MINIKUBE_HOME_DIR}/etc/minikube.pid"
ExecStart=${MINIKUBE_HOME_DIR}/bin/minikube start ${MINIKUBE_OPTS}
ExecStop=${MINIKUBE_HOME_DIR}/bin/minikube stop

Restart=always
SendSIGKILL=no
TasksMax=infinity
TimeoutStopSec=infinity

[Install]
WantedBy=multi-user.target
SYS
}

function systemd(){
    sudo systemctl daemon-reload
    sudo systemctl enable  minikube.service
    sudo systemctl start   minikube.service
    sudo systemctl status  minikube.service
}

function ingress(){
    sudo -i -u minikube bash << EXE
# minikube daemon delay
FOR_FIVE_SECONDS_ONLY=5
sleep \$((FOR_FIVE_SECONDS_ONLY*2))

# minikube enable addons for ingress
for p in ingress ingress-dns dashboard metrics-server;\
do minikube addons enable \${p};done
minikube addons list
EXE

    sudo systemctl restart minikube.service
    sudo systemctl status  minikube.service

    sudo -i -u minikube bash << EXE
# minikube addons delay
FOR_FIVE_SECONDS_ONLY=5
sleep \$((FOR_FIVE_SECONDS_ONLY*2))

# minikube find coredns last entry
CONFIGMAP_COREDNS_FIND=\$(cat <<QRY
        }\n\
        cache 30\n\
        loop\n\
        reload\n\
        loadbalance\n\
    }
QRY
)

# minikube nameserver ip
printf -v MINIKUBE_NSLOOKUP '%s' \$(minikube ip)

# minikube fill coredns last entry
CONFIGMAP_COREDNS_FILL=\$(cat <<UPD
\${CONFIGMAP_COREDNS_FIND}\n\
    k8s.local:53 {\n\
        errors\n\
        cache 30\n\
        forward . \${MINIKUBE_NSLOOKUP}\n\
    }
UPD
)

# minikube update coredns entry for k8s.local
if [[ "\${MINIKUBE_NSLOOKUP}" =~ ^(([1-9]?[0-9]|1[0-9][0-9]|2([0-4][0-9]|5[0-5]))\.){3}([1-9]?[0-9]|1[0-9][0-9]|2([0-4][0-9]|5[0-5]))$ ]];then
    kubectl get configmap coredns -n kube-system -o yaml | sed -z "s|\${CONFIGMAP_COREDNS_FIND}|\$(echo "\${CONFIGMAP_COREDNS_FILL}")|" | kubectl apply -n kube-system -f -
fi

# minikube addons dashboard delay
sleep \$((FOR_FIVE_SECONDS_ONLY*12))

# minikube kubernetes-dashboard's ingress for k8s.local
cat << YML | kubectl apply -n kubernetes-dashboard -f -
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
  labels:
    app.kubernetes.io/version: 1.0.0
    app.kubernetes.io/name: kubernetes-dashboard
    app.kubernetes.io/instance: kubernetes-dashboard
    app.kubernetes.io/managed-by: Chorke-Academia-Inc
spec:
  ingressClassName: nginx
  rules:
    - host: "www.k8s.local"
      http:
        paths:
          - path: /
            pathType: ImplementationSpecific
            backend:
              service:
                name: kubernetes-dashboard
                port:
                  number: 80
YML
EXE
}

function k8sconf(){
    # minikube installer user kubeconfig
    mkdir -p ~/.kube && sudo chmod 755 ~/.kube
    sudo -i -u  minikube kubectl config --kubeconfig=/home/minikube/.kube/config view --flatten | tee ~/.kube/config >/dev/null
    sudo chmod 600 ~/.kube/config

    # minikube sudo or root user kubecofig
    sudo mkdir -p  /root/.kube && sudo chmod 755 /root/.kube
    sudo -i -u  minikube kubectl config --kubeconfig=/home/minikube/.kube/config view --flatten | sudo tee /root/.kube/config >/dev/null
    sudo chmod 600 /root/.kube/config
}

function init(){
    validate
    download
    approve
    setting
    install
    systemd
    ingress
    k8sconf
}

init