#!/bin/bash
# ---------------------------------------------------------
# Kubernetes (K8s) 高可用集群自动化脚本 (Ubuntu 专用 V3 修复版)
# 修复: HAProxy 绑定 VIP 崩溃问题、crictl 警告、自动识别网卡
# ---------------------------------------------------------

# ================= 变量配置区 (执行前务必修改) =================
K8S_VERSION="1.28.2-*"
POD_SUBNET="10.244.0.0/16"
SERVICE_SUBNET="10.96.0.0/12"

# 1. 高可用 VIP 配置
VIP="192.168.1.100"
VIP_PORT="16443"

# 自动获取当前机器的主网卡名称 (如 ens33, eth0)，避免 Keepalived 绑定失败
VIP_INTERFACE=$(ip route | grep default | awk '{print $5}') 

# 2. Master 节点真实 IP 列表
MASTER01_IP="192.168.1.11"
MASTER02_IP="192.168.1.12"
MASTER03_IP="192.168.1.13"

# 控制平面入口地址
CONTROL_PLANE_ENDPOINT="${VIP}:${VIP_PORT}"
# ===============================================================

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m'

if [ "$EUID" -ne 0 ]; then
  echo -e "${RED}请使用 root 权限运行此脚本！${NC}"
  exit 1
fi

function prepare_env() {
    echo -e "${GREEN}==> 开始初始化系统环境 (Ubuntu)...${NC}"
    ufw disable
    systemctl stop ufw && systemctl disable ufw

    swapoff -a
    sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab

    cat <<EOF | tee /etc/modules-load.d/k8s.conf
overlay
br_netfilter
EOF
    modprobe overlay
    modprobe br_netfilter

    # 【核心修复1】增加 ip_nonlocal_bind，允许 HAProxy 绑定还未漂移过来的 VIP
    cat <<EOF | tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-iptables  = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward                 = 1
net.ipv4.ip_nonlocal_bind           = 1 
EOF
    sysctl --system
    echo -e "${GREEN}==> 系统环境初始化完成。${NC}"
}

function install_containerd() {
    echo -e "${GREEN}==> 开始安装 Containerd...${NC}"
    apt-get update -y
    apt-get install -y apt-transport-https ca-certificates curl software-properties-common containerd

    mkdir -p /etc/containerd
    containerd config default > /etc/containerd/config.toml
    sed -i 's/SystemdCgroup = false/SystemdCgroup = true/' /etc/containerd/config.toml
    sed -i 's#registry.k8s.io/pause#registry.aliyuncs.com/google_containers/pause#g' /etc/containerd/config.toml

    systemctl daemon-reload
    systemctl enable --now containerd

    # 【核心修复2】配置 crictl，消除警告
    cat <<EOF | tee /etc/crictl.yaml
runtime-endpoint: unix:///run/containerd/containerd.sock
image-endpoint: unix:///run/containerd/containerd.sock
timeout: 10
debug: false
EOF
    echo -e "${GREEN}==> Containerd 安装配置完成。${NC}"
}

function install_k8s_tools() {
    echo -e "${GREEN}==> 开始安装 kubeadm, kubelet, kubectl...${NC}"
    mkdir -p /etc/apt/keyrings
    rm -f /etc/apt/keyrings/kubernetes-apt-keyring.gpg
    
    curl -fsSL https://mirrors.aliyun.com/kubernetes-new/core/stable/v1.28/deb/Release.key | gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
    echo "deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://mirrors.aliyun.com/kubernetes-new/core/stable/v1.28/deb/ /" | tee /etc/apt/sources.list.d/kubernetes.list

    apt-get update -y
    apt-get install -y kubelet kubeadm kubectl
    apt-mark hold kubelet kubeadm kubectl

    systemctl enable --now kubelet
    echo -e "${GREEN}==> Kubernetes 组件安装完成。${NC}"
}

function setup_vip() {
    local STATE=$1
    local PRIORITY=$2
    
    echo -e "${GREEN}==> 开始配置 HAProxy 和 Keepalived (网卡: ${VIP_INTERFACE})...${NC}"
    apt-get install -y haproxy keepalived

    cat <<EOF | tee /etc/haproxy/haproxy.cfg
global
    log /dev/log local0
    log /dev/log local1 notice
    daemon

defaults
    mode                    tcp
    log                     global
    option                  tcplog
    timeout connect         10s
    timeout client          1m
    timeout server          1m

frontend kubernetes-apiserver
    bind ${VIP}:${VIP_PORT}
    mode tcp
    default_backend kubernetes-master

backend kubernetes-master
    mode tcp
    balance roundrobin
    option tcp-check
    server master01 ${MASTER01_IP}:6443 check
    server master02 ${MASTER02_IP}:6443 check
    server master03 ${MASTER03_IP}:6443 check
EOF

    cat <<EOF | tee /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
}
vrrp_script check_haproxy {
    script "killall -0 haproxy"
    interval 3
    weight -2
    fall 10
    rise 2
}
vrrp_instance VI_1 {
    state ${STATE}
    interface ${VIP_INTERFACE}
    virtual_router_id 51
    priority ${PRIORITY}
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        ${VIP}
    }
    track_script {
        check_haproxy
    }
}
EOF

    systemctl restart haproxy keepalived
    systemctl enable haproxy keepalived
    echo -e "${GREEN}==> HAProxy 和 Keepalived 配置完成 (角色: ${STATE})。${NC}"
}

function init_first_master() {
    echo -e "${YELLOW}==> 正在清理可能残留的 K8s 脏数据...${NC}"
    kubeadm reset -f
    rm -rf /etc/cni/net.d
    rm -rf $HOME/.kube/config
    
    echo -e "${GREEN}==> 检查 VIP 是否存活...${NC}"
    ping -c 3 ${VIP} || echo -e "${RED}警告: 无法 ping 通 VIP ${VIP}，请确保 Keepalived 正常启动且无 IP 冲突！${NC}"

    echo -e "${GREEN}==> 开始初始化第一个 Master 节点...${NC}"
    
    kubeadm init \
      --control-plane-endpoint="${CONTROL_PLANE_ENDPOINT}" \
      --upload-certs \
      --kubernetes-version=v1.28.2 \
      --pod-network-cidr=${POD_SUBNET} \
      --service-cidr=${SERVICE_SUBNET} \
      --image-repository=registry.aliyuncs.com/google_containers

    if [ $? -eq 0 ]; then
        echo -e "${YELLOW}========================================================================${NC}"
        echo -e "${GREEN}集群初始化成功！请妥善保存上面输出的 kubeadm join 命令。${NC}"
        echo -e "${YELLOW}========================================================================${NC}"
        
        export KUBECONFIG=/etc/kubernetes/admin.conf
        mkdir -p $HOME/.kube
        cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
        chown $(id -u):$(id -g) $HOME/.kube/config

        kubectl apply -f https://raw.githubusercontent.com/projectcalico/calico/v3.26.1/manifests/calico.yaml
    else
        echo -e "${RED}集群初始化失败！请使用 'journalctl -xeu kubelet' 检查报错。${NC}"
    fi
}

case "$1" in
    base)
        prepare_env
        install_containerd
        install_k8s_tools
        ;;
    init-vip-master)
        setup_vip "MASTER" 100
        ;;
    init-vip-backup)
        setup_vip "BACKUP" 90
        ;;
    init-master)
        init_first_master
        ;;
    *)
        echo -e "${YELLOW}用法: sudo $0 {base|init-vip-master|init-vip-backup|init-master}${NC}"
        exit 1
esac