#!/usr/bin/env bash

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

set -euo pipefail

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

# ==============================
# 检测 Rocky 版本
# ==============================
detect_version() {
    if [[ -f /etc/os-release ]]; then
        . /etc/os-release
        ROCKY_VER=$(echo "$VERSION_ID" | cut -d. -f1)
    else
        echo "无法检测系统版本"
        exit 1
    fi

    echo "[+] 检测到 Rocky Linux $ROCKY_VER"
}

# ==============================
# 选择镜像源
# ==============================
select_mirror() {

    echo "==============================="
    echo " 选择 Rocky Linux 镜像源"
    echo "==============================="
    echo "1. 阿里云（推荐）"
    echo "2. 清华 TUNA"
    echo "3. 华为云"
    echo "4. 腾讯云"
    echo "5. 官方源"
    echo "==============================="

    read -rp "请输入编号: " choice

    case "$choice" in
        1) BASEURL="https://mirrors.aliyun.com/rockylinux/${ROCKY_VER}" ;;
        2) BASEURL="https://mirrors.tuna.tsinghua.edu.cn/rockylinux/${ROCKY_VER}" ;;
        3) BASEURL="https://repo.huaweicloud.com/rocky/${ROCKY_VER}" ;;
        4) BASEURL="https://mirrors.cloud.tencent.com/rocky/${ROCKY_VER}" ;;
        5) BASEURL="https://dl.rockylinux.org/pub/rocky/${ROCKY_VER}" ;;
        *) echo "无效选择"; exit 1 ;;
    esac
}

# ==============================
# 备份 repo
# ==============================
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
# ==============================
write_repo() {

    echo "[+] 写入 Rocky repo"

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

    cat > "$REPO_FILE" <<EOF
[BaseOS]
name=Rocky Linux \$releasever - BaseOS
baseurl=${BASEURL}/BaseOS/\$basearch/os/
enabled=1
gpgcheck=0

[AppStream]
name=Rocky Linux \$releasever - AppStream
baseurl=${BASEURL}/AppStream/\$basearch/os/
enabled=1
gpgcheck=0

[Extras]
name=Rocky Linux \$releasever - Extras
baseurl=${BASEURL}/extras/\$basearch/os/
enabled=1
gpgcheck=0
EOF

    # Rocky 8/9 额外 repo
    if [[ "$ROCKY_VER" -ge 8 ]]; then

        cat >> "$REPO_FILE" <<EOF

[CRB]
name=Rocky Linux \$releasever - CRB
baseurl=${BASEURL}/CRB/\$basearch/os/
enabled=1
gpgcheck=0
EOF

    fi

}

# ==============================
# 刷新缓存
# ==============================
refresh_cache() {

    echo "[+] 清理缓存"

    dnf clean all

    echo "[+] 构建缓存"

    dnf makecache

}

# ==============================
# 可选组件
# ==============================
install_optional() {

    read -rp "是否安装 EPEL？(y/n): " epel

    if [[ "$epel" == "y" ]]; then
        dnf install -y epel-release || true
    fi

    # Rocky 8/9 推荐启用 CRB
    read -rp "是否启用 CRB？(y/n): " crb

    if [[ "$crb" == "y" ]]; then

        if [[ "$ROCKY_VER" == "8" ]]; then
            dnf config-manager --set-enabled powertools
        else
            dnf config-manager --set-enabled crb
        fi

    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() {

    detect_version

    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
            refresh_cache
            install_optional

            echo "[✔] Rocky 换源完成"
            ;;

        2)

            rollback
            ;;

        *)

            echo "无效选择"
            exit 1
            ;;

    esac

}

main