#!/bin/bash
set -e
set -o pipefail

# ================= 颜色与日志 =================
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
NC='\033[0m'

log_info() { echo -e "${GREEN}[INFO]${NC} $1"; }
log_warn() { echo -e "${YELLOW}[WARN]${NC} $1"; }
log_error() { echo -e "${RED}[ERROR]${NC} $1"; }
log_step() { echo -e "${BLUE}[STEP]${NC} $1"; }
log_success() { echo -e "${CYAN}[OK]${NC} $1"; }

# ================= 参数检查 =================
if [ "$#" -lt 4 ]; then
    echo "========================================"
    log_error "参数数量错误！需要至少 4 个参数"
    echo "用法：$0 <主机名> <IP 地址> <用户名> <密码> [hosts 文件路径]"
    echo "示例：$0 minio1 10.10.21.151 zhengyu MyPass123 /root/.cluster_hosts_temp"
    echo "========================================"
    exit 1
fi

TARGET_NAME="$1"
TARGET_IP="$2"
TARGET_USER="$3"
TARGET_PASS="$4"
HOSTS_FILE="${5:-}"  # 可选参数：集群 hosts 文件路径

KEY_FILE="$HOME/.ssh/id_ed25519_cluster"
SSH_CONFIG="$HOME/.ssh/config"

# 检查并安装sshpass|jq
for pkg in sshpass jq; do
    if ! command -v $pkg &> /dev/null; then
        log_warn "未找到 $pkg，正在安装..."
        
        if command -v apt &> /dev/null; then
            sudo apt update >/dev/null 2>&1 && sudo apt install -y $pkg >/dev/null 2>&1
        elif command -v yum &> /dev/null; then
            sudo yum install -y $pkg >/dev/null 2>&1
        elif command -v dnf &> /dev/null; then
            sudo dnf install -y $pkg >/dev/null 2>&1
        else
            log_error "请手动安装 $pkg"
            exit 1
        fi
        
        log_success "$pkg 安装完成"
    fi
done


log_step "开始初始化单节点：${TARGET_NAME} (${TARGET_IP})"

# ================= 基础环境准备 (本地) =================
mkdir -p "$HOME/.ssh"
touch "$SSH_CONFIG"
chmod 700 "$HOME/.ssh"
chmod 600 "$SSH_CONFIG"

# 生成密钥 (如果不存在)
if [ ! -f "$KEY_FILE" ]; then
    log_step "生成 SSH 密钥对..."
    ssh-keygen -t ed25519 -f "$KEY_FILE" -N "" -q
    log_success "密钥生成成功"
else
    log_info "密钥已存在，跳过生成"
fi
PUB_KEY=$(cat "${KEY_FILE}.pub")

# ================= 准备集群 Hosts 内容 =================
CLUSTER_HOSTS_CONTENT=""
if [ -n "$HOSTS_FILE" ] && [ -f "$HOSTS_FILE" ]; then
    CLUSTER_HOSTS_CONTENT=$(cat "$HOSTS_FILE")
    log_info "已加载集群 Hosts 配置（${#CLUSTER_HOSTS_CONTENT} 字节）"
else
    log_warn "未提供 Hosts 文件，仅配置当前节点解析"
    CLUSTER_HOSTS_CONTENT="$TARGET_IP $TARGET_NAME"
fi

# ================= 更新本地配置 (Hosts & SSH Config) =================
log_step "更新本机配置..."

# 1. 更新 /etc/hosts（添加当前节点）
if grep -q "$TARGET_NAME" /etc/hosts; then
    if ! grep "$TARGET_NAME" /etc/hosts | grep -q "$TARGET_IP"; then
        log_warn "Hosts 中 $TARGET_NAME 已存在但 IP 可能不匹配，跳过修改。"
    else
        log_info "Hosts 记录已存在：$TARGET_NAME"
    fi
else
    echo "$TARGET_IP $TARGET_NAME" | sudo tee -a /etc/hosts > /dev/null
    log_success "已添加 Hosts: $TARGET_IP $TARGET_NAME"
fi

# 2. 更新 SSH Config
MARKER_START="# --- NODE_${TARGET_NAME}_START ---"
MARKER_END="# --- NODE_${TARGET_NAME}_END ---"

if grep -q "$MARKER_START" "$SSH_CONFIG"; then
    sed -i "/$MARKER_START/,/$MARKER_END/d" "$SSH_CONFIG"
fi

cat >> "$SSH_CONFIG" << EOF
$MARKER_START
Host $TARGET_IP $TARGET_NAME
    User $TARGET_USER
    IdentityFile $KEY_FILE
    IdentitiesOnly yes
    StrictHostKeyChecking no
    UserKnownHostsFile /dev/null
    LogLevel ERROR
$MARKER_END
EOF
log_success "SSH Config 已更新：$TARGET_NAME"

# ================= 构建并执行远程脚本 =================
log_step "配置远程节点 ($TARGET_NAME)..."

# 动态生成远程脚本内容
read -r -d '' REMOTE_SCRIPT_CONTENT << EOF || true
#!/bin/bash
USER="\$1"
PASS="\$2"
PUB_KEY="$PUB_KEY"
TARGET_NAME="$TARGET_NAME"
TARGET_IP="$TARGET_IP"
CLUSTER_HOSTS='$CLUSTER_HOSTS_CONTENT'

echo "[Remote] 开始配置用户 \$USER..."

# 1. 配置公钥
mkdir -p ~/.ssh
chmod 700 ~/.ssh
if [ ! -f ~/.ssh/authorized_keys ] || ! grep -qF "\$PUB_KEY" ~/.ssh/authorized_keys; then
    echo "\$PUB_KEY" >> ~/.ssh/authorized_keys
    chmod 600 ~/.ssh/authorized_keys
    echo "[OK] 公钥已添加"
else
    echo "[SKIP] 公钥已存在"
fi

# 2. 配置 Sudo
SUDOERS_FILE="/etc/sudoers.d/nopasswd_\${USER}_auto"
if echo "\$PASS" | sudo -S bash -c "echo '\${USER} ALL=(ALL:ALL) NOPASSWD: ALL' > \$SUDOERS_FILE && chmod 440 \$SUDOERS_FILE"; then
    echo "[OK] Sudo 免密已配置"
else
    echo "[FAIL] Sudo 配置失败"
    exit 1
fi

# 3. 配置集群 Hosts 解析（所有节点互通）
echo "[Remote] 配置集群 Hosts 解析..."
HOSTS_BACKUP="/etc/hosts.backup.\$(date +%Y%m%d_%H%M%S)"

# 备份现有 hosts
sudo cp /etc/hosts "\$HOSTS_BACKUP"
echo "[OK] Hosts 已备份：\$HOSTS_BACKUP"

# 逐行添加集群 hosts（去重）
while IFS= read -r host_line; do
    [ -z "\$host_line" ] && continue
    
    # 提取主机名和 IP
    h_ip=\$(echo "\$host_line" | awk '{print \$1}')
    h_name=\$(echo "\$host_line" | awk '{print \$2}')
    
    [ -z "\$h_ip" ] || [ -z "\$h_name" ] && continue
    
    # 检查是否已存在，不存在则添加
    if sudo grep -q "\$h_name" /etc/hosts; then
        # 检查 IP 是否匹配
        if ! sudo grep "\$h_name" /etc/hosts | grep -q "\$h_ip"; then
            echo "[WARN] \$h_name 已存在但 IP 不匹配，跳过：\$h_ip \$h_name"
        else
            echo "[SKIP] \$h_name 已存在：\$h_ip \$h_name"
        fi
    else
        echo "\$h_ip \$h_name" | sudo tee -a /etc/hosts > /dev/null
        echo "[OK] 已添加：\$h_ip \$h_name"
    fi
done <<< "\$CLUSTER_HOSTS"

# 4. 验证 hosts 解析
echo "[Remote] 验证 Hosts 解析..."
if sudo grep -q "\$TARGET_NAME" /etc/hosts; then
    echo "[OK] 当前节点解析验证通过"
else
    echo "[FAIL] 当前节点解析验证失败"
fi

# 显示当前 hosts 配置
echo ""
echo "[Remote] 当前 /etc/hosts 配置:"
sudo grep -E "^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+" /etc/hosts | tail -n 20

echo ""
echo "[Remote] 单节点初始化完成!"
EOF

# 上传脚本
TMP_REMOTE="/tmp/init_single_node.sh"
echo "$REMOTE_SCRIPT_CONTENT" > /tmp/local_tmp_script.sh
chmod +x /tmp/local_tmp_script.sh

if ! sshpass -p "$TARGET_PASS" scp -o ConnectTimeout=10 -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null /tmp/local_tmp_script.sh "$TARGET_USER@$TARGET_IP:$TMP_REMOTE" 2>/dev/null; then
    log_error "上传脚本失败"
    rm -f /tmp/local_tmp_script.sh
    exit 1
fi

# 执行脚本
CMD="chmod +x $TMP_REMOTE && $TMP_REMOTE \"$TARGET_USER\" \"$TARGET_PASS\""
if sshpass -p "$TARGET_PASS" ssh -o ConnectTimeout=10 -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -n "$TARGET_USER@$TARGET_IP" "$CMD"; then
    log_success "节点 $TARGET_NAME 初始化成功!"
else
    log_error "节点 $TARGET_NAME 执行失败"
    rm -f /tmp/local_tmp_script.sh
    exit 1
fi

# 清理
rm -f /tmp/local_tmp_script.sh

echo "========================================"
log_success "✅ 节点 ${TARGET_NAME} 就绪!"
log_info "������ 测试连接：ssh $TARGET_NAME"
echo "========================================"