#!/bin/bash

# 如果遇到windows格式污染请执行：
# sed -i 's/\r$//' updatesource.sh

set -euo pipefail

REPO_DIR="/etc/yum.repos.d"
BACKUP_DIR="${REPO_DIR}/backup_$(date +%F_%H-%M-%S)"
REPO_FILE="${REPO_DIR}/CentOS-Base.repo"

# ==============================
# 选择源
# ==============================
select_mirror() {
    echo "==============================="
    echo " 选择 CentOS 7 Vault 源"
    echo "==============================="
    echo "1. 阿里云（推荐）"
    echo "2. 清华 TUNA"
    echo "3. 华为云"
    echo "4. 网易"
    echo "5. 官方 vault"
    echo "==============================="

    read -rp "请输入编号: " choice

    case "$choice" in
        1) BASEURL="http://mirrors.aliyun.com/centos-vault/7.9.2009" ;;
        2) BASEURL="https://mirrors.tuna.tsinghua.edu.cn/centos-vault/7.9.2009" ;;
        3) BASEURL="https://repo.huaweicloud.com/centos-vault/7.9.2009" ;;
        4) BASEURL="http://mirrors.163.com/centos-vault/7.9.2009" ;;
        5) BASEURL="https://vault.centos.org/7.9.2009" ;;
        *) echo "无效选择"; exit 1 ;;
    esac
}

# ==============================
# 备份
# ==============================
backup_repo() {
    echo "[+] 备份 repo → $BACKUP_DIR"
    mkdir -p "$BACKUP_DIR"
    cp -a ${REPO_DIR}/*.repo "$BACKUP_DIR"/ 2>/dev/null || true
}

# ==============================
# 写入 repo（无 EOF 版本）
# ==============================
write_repo() {
    echo "[+] 写入新 repo"

    # 清理旧 repo
    mkdir -p "${REPO_DIR}/bak_old"
    mv ${REPO_DIR}/*.repo "${REPO_DIR}/bak_old/" 2>/dev/null || true

    # 写入新 repo
    {
        echo "[base]"
        echo "name=CentOS-7 - Base"
        echo "baseurl=${BASEURL}/os/x86_64/"
        echo "enabled=1"
        echo "gpgcheck=0"
        echo ""

        echo "[updates]"
        echo "name=CentOS-7 - Updates"
        echo "baseurl=${BASEURL}/updates/x86_64/"
        echo "enabled=1"
        echo "gpgcheck=0"
        echo ""

        echo "[extras]"
        echo "name=CentOS-7 - Extras"
        echo "baseurl=${BASEURL}/extras/x86_64/"
        echo "enabled=1"
        echo "gpgcheck=0"
    } > "$REPO_FILE"
}

# ==============================
# fastestmirror 控制
# ==============================
config_fastestmirror() {
    CONF_FILE="/etc/yum/pluginconf.d/fastestmirror.conf"

    if [[ ! -f "$CONF_FILE" ]]; then
        echo "[!] 未找到 fastestmirror 插件，跳过"
        return
    fi

    read -rp "是否关闭 fastestmirror？(y/n): " fm

    if [[ "$fm" == "y" ]]; then
        sed -i 's/^enabled=.*/enabled=0/' "$CONF_FILE"
        echo "[+] 已关闭 fastestmirror"
    else
        sed -i 's/^enabled=.*/enabled=1/' "$CONF_FILE"
        echo "[+] 已开启 fastestmirror"
    fi
}

# ==============================
# 刷新缓存
# ==============================
refresh_cache() {
    echo "[+] 清理缓存"
    yum clean all

    echo "[+] 构建缓存"
    yum makecache
}

# ==============================
# 可选组件
# ==============================
install_optional() {
    read -rp "是否安装 EPEL？(y/n): " epel
    if [[ "$epel" == "y" ]]; then
        yum install -y epel-release || true
    fi

    read -rp "是否启用 SCLo？(y/n): " sclo
    if [[ "$sclo" == "y" ]]; then
        yum install -y centos-release-scl || true
    fi
}

# ==============================
# 回滚
# ==============================
rollback() {
    echo "[!] 可用备份："
    ls -d ${REPO_DIR}/backup_* 2>/dev/null || {
        echo "没有备份"
        exit 1
    }

    read -rp "输入备份路径: " dir

    if [[ -d "$dir" ]]; then
        rm -f ${REPO_DIR}/*.repo
        cp -a "$dir"/*.repo "$REPO_DIR"/
        echo "[✓] 回滚完成"
    else
        echo "[✗] 目录不存在"
        exit 1
    fi
}

# ==============================
# 主流程
# ==============================
main() {
    echo "1. 更换源"
    echo "2. 回滚"
    read -rp "请选择: " action

    case "$action" in
        1)
            select_mirror
            backup_repo
            write_repo
            config_fastestmirror
            refresh_cache
            install_optional
            echo "[✔] 完成"
            ;;
        2)
            rollback
            ;;
        *)
            echo "无效选择"
            exit 1
            ;;
    esac
}

main