#!/bin/bash
# 清掉用不上的服务，给中转服务器腾内存。
# 用户明确授权：除了系统，其他装的软件都可以删。
#
# 目标服务（hexo 博客那一套，hexo 目录已经删了，这套已经没意义）：
#     apache2      网站服务
#     mariadb      数据库
#     php8.2-fpm   PHP
# 这三个加起来通常占 80~120MB，对 460MB 的机器是很大一块。
set -u

echo "===== 先看现在谁在吃内存 ====="
ps -eo rss,comm --sort=-rss 2>/dev/null | head -14 | \
    awk 'NR==1{print "  RSS(KB)  进程"} NR>1{printf "  %-8s %s\n", $1, $2}'

echo
echo "===== 清之前 ====="
free -m | head -2

# 先看这些服务在不在
TARGETS=""
for svc in apache2 mariadb php8.2-fpm mysql; do
    if systemctl list-unit-files 2>/dev/null | grep -q "^${svc}\.service"; then
        TARGETS="$TARGETS $svc"
    fi
done
echo
echo "找到的服务：${TARGETS:-（无）}"

if [ -n "$TARGETS" ]; then
    for svc in $TARGETS; do
        systemctl stop "$svc" 2>/dev/null && echo "  已停止 $svc"
        systemctl disable "$svc" 2>/dev/null && echo "  已禁止开机启动 $svc"
    done
fi

echo
echo "===== 停掉之后 ====="
sleep 2
free -m | head -2

echo
echo "===== 卸载相关软件包 ====="
PKGS=""
for pkg in apache2 apache2-bin apache2-data apache2-utils \
           mariadb-server mariadb-server-10.11 mariadb-client \
           mariadb-client-10.11 mariadb-common \
           php8.2-fpm php8.2-cli php8.2-common php8.2-mysql php8.2-opcache \
           libapache2-mod-php8.2; do
    if dpkg-query -W -f='${Status}' "$pkg" 2>/dev/null | grep -q "install ok installed"; then
        PKGS="$PKGS $pkg"
    fi
done
echo "  待卸载：${PKGS:-（无）}"

if [ -n "$PKGS" ]; then
    DEBIAN_FRONTEND=noninteractive apt-get purge -y $PKGS >/dev/null 2>&1 \
        && echo "  卸载完成" || echo "  卸载有报错（部分包可能被别的依赖）"
    DEBIAN_FRONTEND=noninteractive apt-get autoremove -y >/dev/null 2>&1
    apt-get clean >/dev/null 2>&1
fi

echo
echo "===== 最终状态 ====="
free -m | head -2
echo
df -h / | tail -1
echo
echo "===== 还在跑的服务 ====="
systemctl list-units --type=service --state=running --no-pager --no-legend 2>/dev/null | \
    awk '{print "  " $1}' | head -20
echo
echo "===== 内存占用 TOP ====="
ps -eo rss,comm --sort=-rss 2>/dev/null | head -12 | \
    awk 'NR==1{print "  RSS(KB)  进程"} NR>1{printf "  %-8s %s\n", $1, $2}'