#!/bin/bash

# =================================================================
#  Debian 12 (bookworm) APT 源自动配置脚本（阿里云镜像）
#  功能:
#  1. 备份现有的 sources.list 文件
#  2. 使用阿里云镜像源覆盖 sources.list
#  3. 执行 apt update
#  4. 安装 curl
# =================================================================

SOURCES_FILE="/etc/apt/sources.list"
BACKUP_FILE="${SOURCES_FILE}.bak.$(date +%Y%m%d-%H%M%S)"

read -r -d '' NEW_SOURCES_CONTENT << 'EOF'
# =====================================================
# Debian 12 (bookworm) - Aliyun Mirrors
# =====================================================

deb https://mirrors.aliyun.com/debian/ bookworm main contrib non-free non-free-firmware
# deb-src https://mirrors.aliyun.com/debian/ bookworm main contrib non-free non-free-firmware

deb https://mirrors.aliyun.com/debian/ bookworm-updates main contrib non-free non-free-firmware
# deb-src https://mirrors.aliyun.com/debian/ bookworm-updates main contrib non-free non-free-firmware

deb https://mirrors.aliyun.com/debian-security/ bookworm-security main contrib non-free non-free-firmware
# deb-src https://mirrors.aliyun.com/debian-security/ bookworm-security main contrib non-free non-free-firmware
EOF

echo "===== [0/4] 检查运行权限 ====="
if [ "$(id -u)" -ne 0 ]; then
    echo "错误：此脚本必须以 root 用户身份运行。" >&2
    echo "请使用 'sudo bash update_sources_debian12.sh' 执行。" >&2
    exit 1
fi
echo "权限检查通过。"
echo ""

echo "===== [1/4] 备份原始源文件 ====="
if [ -f "$SOURCES_FILE" ]; then
    cp "$SOURCES_FILE" "$BACKUP_FILE"
    echo "原始文件已备份到: $BACKUP_FILE"
else
    echo "原始文件不存在，将创建新文件。"
fi
echo ""

echo "===== [2/4] 写入新的阿里云镜像源 ====="
echo "$NEW_SOURCES_CONTENT" > "$SOURCES_FILE"
echo "新的源配置已写入 $SOURCES_FILE"
echo ""

echo "===== [3/4] 执行 apt update ====="
apt-get update
if [ $? -ne 0 ]; then
    echo "错误：apt update 执行失败！" >&2
    echo "原始 sources.list 已备份在：$BACKUP_FILE" >&2
    exit 1
fi
echo "软件包列表更新成功。"
echo ""

echo "===== [4/4] 安装 curl ====="
apt-get install -y curl
if ! command -v curl >/dev/null 2>&1; then
    echo "错误：curl 安装失败！" >&2
    exit 1
fi

echo "Curl 已成功安装！"
curl --version
echo ""
echo "脚本执行完毕，Debian 12 阿里云源配置成功！"