#!/bin/bash

# vim: ts=4 sw=4 sts=4 et tw=72 :

# force any errors to cause the script and job to end in failure
set -xeu -o pipefail

ensure_kernel_install() {
    # Workaround for mkinitrd failing on occassion.
    # On CentOS 7 it seems like the kernel install can fail it's mkinitrd
    # run quietly, so we may not notice the failure. This script retries for a
    # few times before giving up.
    initramfs_ver=$(rpm -q kernel | tail -1 | sed "s/kernel-/initramfs-/")
    grub_conf="/boot/grub/grub.conf"
    # Public cloud does not use /boot/grub/grub.conf and uses grub2 instead.
    if [ ! -e "$grub_conf" ]; then
        echo "$grub_conf not found. Using Grub 2 conf instead."
        grub_conf="/boot/grub2/grub.cfg"
    fi

    for i in $(seq 3); do
        if grep "$initramfs_ver" "$grub_conf"; then
            break
        fi
        echo "Kernel initrd missing. Retrying to install kernel..."
        yum reinstall -y kernel
    done
    if ! grep "$initramfs_ver" "$grub_conf"; then
        cat /boot/grub/grub.conf
        echo "ERROR: Failed to install kernel."
        exit 1
    fi
}

ensure_ubuntu_install() {
    # Workaround for mirrors occassionally failing to install a package.
    # On Ubuntu sometimes the mirrors fail to install a package. This wrapper
    # checks that a package is successfully installed before moving on.

    packages=($@)

    for pkg in "${packages[@]}"
    do
        # Retry installing package 5 times if necessary
        for i in {0..5}
        do
            if [ "$(dpkg-query -W -f='${Status}' "$pkg" 2>/dev/null | grep -c "ok installed")" -eq 0 ]; then
                apt-cache policy "$pkg"
                apt-get install "$pkg"
                continue
            else
                echo "$pkg already installed."
                break
            fi
        done
    done
}

rh_systems() {
    # Handle the occurance where SELINUX is actually disabled
    SELINUX=$(grep -E '^SELINUX=(disabled|permissive|enforcing)$' /etc/selinux/config)
    MODE=$(echo "$SELINUX" | cut -f 2 -d '=')
    case "$MODE" in
        permissive)
            echo "************************************"
            echo "** SYSTEM ENTERING ENFORCING MODE **"
            echo "************************************"
            # make sure that the filesystem is properly labelled.
            # it could be not fully labeled correctly if it was just switched
            # from disabled, the autorelabel misses some things
            # skip relabelling on /dev as it will generally throw errors
            restorecon -R -e /dev /

            # enable enforcing mode from the very start
            setenforce enforcing

            # configure system for enforcing mode on next boot
            sed -i 's/SELINUX=permissive/SELINUX=enforcing/' /etc/selinux/config
        ;;
        disabled)
            sed -i 's/SELINUX=disabled/SELINUX=permissive/' /etc/selinux/config
            touch /.autorelabel

            echo "*******************************************"
            echo "** SYSTEM REQUIRES A RESTART FOR SELINUX **"
            echo "*******************************************"
        ;;
        enforcing)
            echo "*********************************"
            echo "** SYSTEM IS IN ENFORCING MODE **"
            echo "*********************************"
        ;;
    esac

    # Allow jenkins access to alternatives command to switch java version
    cat <<EOF >/etc/sudoers.d/89-jenkins-user-defaults
Defaults:jenkins !requiretty
jenkins ALL = NOPASSWD: /usr/sbin/alternatives
EOF

    echo "---> Updating operating system"
    yum clean all
    yum install -y deltarpm
    yum update -y

    ensure_kernel_install

    # add in components we need or want on systems
    echo "---> Installing base packages"
    yum install -y @base https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
    # separate group installs from package installs since a non-existing
    # group with dnf based systems (F21+) will fail the install if such
    # a group does not exist
    yum install -y unzip xz puppet git git-review perl-XML-XPath
    yum install -y python-{devel,virtualenv,setuptools,pip}

    # All of our systems require Java (because of Jenkins)
    # Install all versions of the OpenJDK devel but force 1.7.0 to be the
    # default

    echo "---> Configuring OpenJDK"
    yum install -y 'java-*-openjdk-devel'

    FACTER_OS=$(/usr/bin/facter operatingsystem)
    FACTER_OSVER=$(/usr/bin/facter operatingsystemrelease)
    case "$FACTER_OS" in
        Fedora)
            if [ "$FACTER_OSVER" -ge "21" ]
            then
                echo "---> not modifying java alternatives as OpenJDK 1.7.0 does not exist"
            else
                alternatives --set java /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
                alternatives --set java_sdk_openjdk /usr/lib/jvm/java-1.7.0-openjdk.x86_64
            fi
        ;;
        RedHat|CentOS)
            if [ "$(echo "$FACTER_OSVER" | cut -d'.' -f1)" -ge "7" ]
            then
                echo "---> not modifying java alternatives as OpenJDK 1.7.0 does not exist"
            else
                alternatives --set java /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
                alternatives --set java_sdk_openjdk /usr/lib/jvm/java-1.7.0-openjdk.x86_64
            fi
        ;;
        *)
            alternatives --set java /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
            alternatives --set java_sdk_openjdk /usr/lib/jvm/java-1.7.0-openjdk.x86_64
        ;;
    esac

    ########################
    # --- START LFTOOLS DEPS

    # Used by various scripts to push patches to Gerrit
    yum install -y git-review

    # Needed to parse OpenStack commands used by opendaylight-infra stack commands
    # to initialize Heat template based systems.
    yum install -y jq

    # Used by lftools scripts to parse XML
    yum install -y xmlstarlet

    # Haskel Packages
    # Cabal update fails on a 1G system so workaround that with a swap file
    dd if=/dev/zero of=/tmp/swap bs=1M count=1024
    mkswap /tmp/swap
    swapon /tmp/swap

    yum install -y cabal-install
    cabal update
    cabal install "Cabal<1.18"  # Pull Cabal version that is capable of building shellcheck
    cabal install --bindir=/usr/local/bin "shellcheck-0.4.6"  # Pin shellcheck version

    # --- END LFTOOLS DEPS
    ######################

    # install haveged to avoid low entropy rejecting ssh connections
    yum install -y haveged
    systemctl enable haveged.service
}

ubuntu_systems() {
    # Ignore SELinux since slamming that onto Ubuntu leads to
    # frustration

    # Allow jenkins access to update-alternatives command to switch java version
    cat <<EOF >/etc/sudoers.d/89-jenkins-user-defaults
Defaults:jenkins !requiretty
jenkins ALL = NOPASSWD: /usr/bin/update-alternatives
EOF

    export DEBIAN_FRONTEND=noninteractive
    cat <<EOF >> /etc/apt/apt.conf
APT {
  Get {
    Assume-Yes "true";
    allow-change-held-packages "true";
    allow-downgrades "true";
    allow-remove-essential "true";
  };
};

Dpkg::Options {
  "--force-confdef";
  "--force-confold";
};

EOF

    # Add hostname to /etc/hosts to fix 'unable to resolve host' issue with sudo
    sed -i "/127.0.0.1/s/$/ $(hostname)/" /etc/hosts

    echo "---> Updating operating system"

    # add additional repositories
    sudo add-apt-repository "deb http://us.archive.ubuntu.com/ubuntu $(lsb_release -sc) main universe restricted multiverse"

    echo "---> Installing base packages"
    apt-get clean
    apt-get update -m
    apt-get upgrade -m
    apt-get dist-upgrade -m

    ensure_ubuntu_install unzip xz-utils puppet git libxml-xpath-perl

    # install Java 7
    echo "---> Configuring OpenJDK"
    FACTER_OSVER=$(/usr/bin/facter operatingsystemrelease)
    case "$FACTER_OSVER" in
        14.04)
            apt-get install openjdk-7-jdk
            # make jdk8 available
            add-apt-repository -y ppa:openjdk-r/ppa
            apt-get update
            # We need to force openjdk-8-jdk to install
            apt-get install openjdk-8-jdk
            # make sure that we still default to openjdk 7
            update-alternatives --set java /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java
            update-alternatives --set javac /usr/lib/jvm/java-7-openjdk-amd64/bin/javac
        ;;
        16.04)
            apt-get install openjdk-8-jdk
        ;;
        *)
            echo "---> Unknown Ubuntu version $FACTER_OSVER"
            exit 1
        ;;
    esac

    ########################
    # --- START LFTOOLS DEPS

    # Used by various scripts to push patches to Gerrit
    ensure_ubuntu_install git-review

    # Needed to parse OpenStack commands used by opendaylight-infra stack commands
    # to initialize Heat template based systems.
    ensure_ubuntu_install jq

    # Used by lftools scripts to parse XML
    ensure_ubuntu_install xmlstarlet

    # Change made by zdw on 2018-04-12
    # hackage.haskell.org was down, talked to zxiiro on #lf-releng and he recommended
    # pulling down the packages in a way similar to this ansible role, rather than using cabal:
    # https://github.com/lfit/ansible-roles-shellcheck-install/blob/master/tasks/main.yml

    SHELLCHECK_VERSION="v0.4.7"
    SHELLCHECK_SHA256SUM="deeea92a4d3a9c5b16ba15210d9c1ab84a2e12e29bf856427700afd896bbdc93"
    curl -L -o /tmp/shellcheck.tar.xz https://storage.googleapis.com/shellcheck/shellcheck-${SHELLCHECK_VERSION}.linux.x86_64.tar.xz
    echo "$SHELLCHECK_SHA256SUM  /tmp/shellcheck.tar.xz" | sha256sum -c -
    pushd /tmp
    tar -xJvf shellcheck.tar.xz
    cp shellcheck-${SHELLCHECK_VERSION}/shellcheck /usr/local/bin/shellcheck
    chmod a+x /usr/local/bin/shellcheck
    popd

    # --- END LFTOOLS DEPS
    ######################

    # install haveged to avoid low entropy rejecting ssh connections
    apt-get install haveged
    update-rc.d haveged defaults

    # disable unattended upgrades & daily updates
    echo '---> Disabling automatic daily upgrades'
    sed -ine 's/"1"/"0"/g' /etc/apt/apt.conf.d/10periodic
    echo 'APT::Periodic::Unattended-Upgrade "0";' >> /etc/apt/apt.conf.d/10periodic
}

all_systems() {
    # Do any Distro specific installations here
    echo "Checking distribution"
    FACTER_OS=$(/usr/bin/facter operatingsystem)
    case "$FACTER_OS" in
        *)
            echo "---> $FACTER_OS found"
            echo "No extra steps for $FACTER_OS"
        ;;
    esac
}

echo "---> Attempting to detect OS"
# upstream cloud images use the distro name as the initial user
ORIGIN=$(if [ -e /etc/redhat-release ]
    then
        echo redhat
    else
        echo ubuntu
    fi)
#ORIGIN=$(logname)

case "${ORIGIN}" in
    fedora|centos|redhat)
        echo "---> RH type system detected"
        rh_systems
    ;;
    ubuntu)
        echo "---> Ubuntu system detected"
        ubuntu_systems
    ;;
    *)
        # Kill the build for unhandled distributions
        echo "---> Unknown operating system" 1>&2
        exit 1
    ;;
esac

# execute steps for all systems
all_systems