#!/bin/bash
#
## Wizard Kit: Live Linux Build Tool

# Prep
DATE="$(date +%F)"
DATETIME="$(date +%F_%H%M)"
ROOT_DIR="$(realpath $(dirname "$0"))"
BUILD_DIR="$ROOT_DIR/BUILD_LINUX"
LIVE_DIR="$BUILD_DIR/live"
LOG_DIR="$BUILD_DIR/logs"
OUT_DIR="$ROOT_DIR/OUT_LINUX"
REPO_DIR="$BUILD_DIR/repo"
SKEL_DIR="$LIVE_DIR/airootfs/etc/skel"
TEMP_DIR="$BUILD_DIR/temp"
MIRRORLIST_SOURCE='https://www.archlinux.org/mirrorlist/?country=US&protocol=http&protocol=https&ip_version=4&use_mirror_status=on'
if which nano >/dev/null 2>&1; then
    EDITOR=nano
elif which vim >/dev/null 2>&1; then
    EDITOR=vim
else
    EDITOR=vi
fi
if which sudo >/dev/null 2>&1; then
    REAL_USER="$SUDO_USER"
fi

function ask() {
    while :; do
        read -p "$1 " -r answer
        if echo "$answer" | egrep -iq '^(y|yes|sure)$'; then
            return 0
        elif echo "$answer" | egrep -iq '^(n|no|nope)$'; then
            return 1
        fi
    done
}
        
function cleanup() {
    for d in "$TEMP_DIR" "$LIVE_DIR"; do
        if [[ -d "$d" ]]; then
            if ask "Remove: ${d}?"; then
                rm -Rf "$d"
            fi
        fi
    done
    mkdir "$BUILD_DIR" 2>/dev/null
    mkdir "$LOG_DIR" 2>/dev/null
    mkdir "$OUT_DIR" 2>/dev/null
    mkdir "$TEMP_DIR" 2>/dev/null
}

function copy_archiso() {
    echo "Copying Archlinux files..."
    rsync -aI /usr/share/archiso/configs/releng/ "$LIVE_DIR/"
    
    # Add items
    rsync -aI "$ROOT_DIR/.linux_items/include/live/" "$LIVE_DIR/"

    # Remove items
    rm "$LIVE_DIR/airootfs/etc/systemd/scripts/choose-mirror"
    rmdir "$LIVE_DIR/airootfs/etc/systemd/scripts" --ignore-fail-on-non-empty
    rm "$LIVE_DIR/airootfs/etc/systemd/system/choose-mirror.service"
    rm "$LIVE_DIR/airootfs/etc/systemd/system/etc-pacman.d-gnupg.mount"
    rm "$LIVE_DIR/airootfs/etc/systemd/system/pacman-init.service"
    rm "$LIVE_DIR/airootfs/etc/udev/rules.d/81-dhcpcd.rules"
    rmdir "$LIVE_DIR/airootfs/etc/udev/rules.d" --ignore-fail-on-non-empty
    rmdir "$LIVE_DIR/airootfs/etc/udev" --ignore-fail-on-non-empty
}

function fix_kit_permissions() {
    # GitHub zip archives don't preserve the correct permissions
    for d in .bin .cbin .kit_items .linux_items .pe_items Images; do
        find "$ROOT_DIR/$d" -type d -exec chmod 755 "{}" \;
    done
}

function load_settings() {
    # Check if settings already loaded
    ## Code based on StackOverflow Q&A
    ## Question:    https://stackoverflow.com/q/3601515
    ## Asked by:    https://stackoverflow.com/users/260127/prosseek
    ## Edited by:   https://stackoverflow.com/users/3924118/nbro
    ## Answer:      https://stackoverflow.com/a/13864829
    ## Answer by:   https://stackoverflow.com/users/1633643/lionel
    ## Answer edit: https://stackoverflow.com/users/-1/community
    if [ -z ${KIT_NAME_FULL+x} ]; then
        # KIT_NAME_FULL is unset
        : # pass
    else
        # KIT_NAME_FULL is set
        return 0 # Skip loading settings from main.py
    fi

    # Copy settings
    if [[ ! -e "$BUILD_DIR/main.py" ]] || ask "Overwrite main.py?"; then
        cp -bv "$ROOT_DIR/.bin/Scripts/settings/main.py" "$BUILD_DIR/main.py"
    fi

    # Edit settings
    read -p "Press Enter to open settings... " -r
    "$EDITOR" "$BUILD_DIR/main.py"

    # Load settings
    while read line; do
        if echo "$line" | egrep -q "^\w+='"; then
            line="$(echo "$line" | sed -r 's/[\r\n]+//')"
            eval "$line"
        fi
    done < "$BUILD_DIR/main.py"
}

function run_elevated() {
    prog="$1"
    shift
    if which sudo >/dev/null 2>&1; then
        sudo "$prog" $*
    else
        echo -n "Root "
        su -c "export REAL_USER=$USER && '$prog' $*"
    fi
}

function update_archlive() {
    hostname="$(echo "${KIT_NAME_SHORT}-linux" | tr "[:upper:]" "[:lower:]")"
    username="$(echo "${KIT_NAME_SHORT}tech" | tr "[:upper:]" "[:lower:]")"
    
    # build.sh
    if ! grep -iq 'customize_iso' "$LIVE_DIR/build.sh"; then
        sed -ir "s!run_once make_iso\$!# customize_iso\ncp -a \"$ROOT_DIR/.linux_items/include/iso\"/* \"\${work_dir}/iso\"/\n\nrun_once make_iso!" "$LIVE_DIR/build.sh"
    fi

    # Hostname
    echo "$hostname" > "$LIVE_DIR/airootfs/etc/hostname"
    echo "127.0.1.1  $hostname.localdomain  $hostname" >> "$LIVE_DIR/airootfs/etc/hosts"
    
    # Live packages
    sed -i -r 's/^(b43|clonezilla|gpm|grml|refind|testdisk|vim)/#\1/' "$LIVE_DIR/packages.both"
    cat "$ROOT_DIR/.linux_items/packages/live" >> "$LIVE_DIR/packages.both"
    echo "[custom]" >> "$LIVE_DIR/pacman.conf"
    echo "SigLevel = Optional TrustAll" >> "$LIVE_DIR/pacman.conf"
    echo "Server = file://$REPO_DIR" >> "$LIVE_DIR/pacman.conf"

    # Locale
    echo 'sed -i "s/#FallbackNTP/NTP/" /etc/systemd/timesyncd.conf' >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # Mirrors
    sed -i -r 's/^(.*mirrorlist.*)$/#NOPE#\1/' "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    echo "curl -o '/etc/pacman.d/mirrorlist' '$MIRRORLIST_SOURCE'" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    echo "sed -i 's/#Server/Server/g' /etc/pacman.d/mirrorlist" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    
    # MOTD
    sed -i "s/WK/$KIT_NAME_SHORT/" "$LIVE_DIR/airootfs/etc/motd"

    # Oh My ZSH
    git clone --depth=1 git://github.com/robbyrussell/oh-my-zsh.git "$SKEL_DIR/.oh-my-zsh"
    rm -Rf "$SKEL_DIR/.oh-my-zsh/.git"
    curl -o "$SKEL_DIR/.oh-my-zsh/themes/lean.zsh-theme" https://raw.githubusercontent.com/miekg/lean/master/prompt_lean_setup
    
    # Services
    sed -i -r 's/^(.*pacman-init.*)$/#NOPE#\1/' "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    sed -i -r 's/^(.*choose-mirror.*)$/#NOPE#\1/' "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    
    # SSH
    mkdir -p "$SKEL_DIR/.ssh"
    ssh-keygen -b 4096 -C "$username@$hostname" -N "" -f "$SKEL_DIR/.ssh/id_rsa"
    echo 'rm /root/.ssh/id*' >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    echo 'rm /root/.zlogin' >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    sed -i -r 's/^(.*PermitRootLogin.*)$/#NOPE#\1/' "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    
    # Root user
    echo "echo 'root:$LINUX_ROOT_PASSWORD' | chpasswd" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # Sudo
    echo "echo '%wheel ALL=(ALL) NOPASSWD: ALL' >> /etc/sudoers" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # Tech user
    echo "groupadd -r autologin" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    echo "useradd -m -s /bin/zsh -G autologin,power,storage,wheel -U $username" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"
    echo "echo '$username:$LINUX_TECH_PASSWORD' | chpasswd" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # Tech user autologin
    mkdir -p "$LIVE_DIR/airootfs/etc/systemd/system/getty@tty1.service.d"
    echo "[Service]" >> "$LIVE_DIR/airootfs/etc/systemd/system/getty@tty1.service.d/autologin.conf"
    echo "ExecStart=" >> "$LIVE_DIR/airootfs/etc/systemd/system/getty@tty1.service.d/autologin.conf"
    echo "ExecStart=-/sbin/agetty --autologin $username --noclear %I 38400 linux" >> "$LIVE_DIR/airootfs/etc/systemd/system/getty@tty1.service.d/autologin.conf"

    # Timezone
    sed -i -r "s#zoneinfo/UTC#$LINUX_TIME_ZONE#g" "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # udevil fix
    echo "mkdir /media" >> "$LIVE_DIR/airootfs/root/customize_airootfs.sh"

    # Wallpaper
    mkdir -p "$LIVE_DIR/airootfs/usr/share/wallpaper"
    cp "$ROOT_DIR/Images/Linux.png" "$LIVE_DIR/airootfs/usr/share/wallpaper/burned.in"
}

function update_repo() {
    if [[ "$EUID" -eq 0 ]]; then
        echo "This section not meant to be run as root."
        echo "Aborted."
        exit 1
    fi
    echo "Updating custom repo..."

    # Archive current files
    if [[ -d "$REPO_DIR" ]]; then
        mkdir "$BUILD_DIR/Archive" 2>/dev/null
        archive="$BUILD_DIR/Archive/$(date "+%F_%H%M%S")"
        mv -bv "$REPO_DIR" "$archive"
    fi
    sleep 1s

    # Build custom repo packages
    mkdir "$REPO_DIR" 2>/dev/null
    mkdir "$TEMP_DIR" 2>/dev/null
    pushd "$TEMP_DIR" >/dev/null
    while read -r p; do
        echo "Building: $p"
        curl -LsfO https://aur.archlinux.org/cgit/aur.git/snapshot/$p.tar.gz
        tar xf $p.tar.gz
        pushd $p >/dev/null
        makepkg -s --noconfirm
        popd >/dev/null
        mv -n $p/*xz "$REPO_DIR"/
    done < "$ROOT_DIR/.linux_items/packages/aur"
    popd >/dev/null

    # Build custom repo database
    pushd "$REPO_DIR" >/dev/null
    repo-add custom.db.tar.gz *xz
    popd >/dev/null
}

function install_deps() {
    echo "Installing dependencies..."
    packages=
    while read -r line; do
        packages="$packages $line"
    done < "$ROOT_DIR/.linux_items/packages/dependencies"
    run_elevated pacman -Syu --needed --noconfirm $packages
}

function build_arch() {
    if [[ "$EUID" -ne 0 ]]; then
        echo "This section is meant to be run as root."
        echo "Aborted."
        exit 1
    fi
    
    # Set permissions
    echo "Setting permissions..."
    chown root:root "$LIVE_DIR" -R
    chmod 700 "$LIVE_DIR/airootfs/etc/skel/.ssh"
    chmod 600 "$LIVE_DIR/airootfs/etc/skel/.ssh/id_rsa"
    
    # Build ISO
    prefix="$(< "$LIVE_DIR/airootfs/etc/hostname")"
    label="${KIT_NAME_SHORT}_LINUX"
    "$LIVE_DIR/build.sh" -N "$prefix" -V "$DATE" -L "$label" -w "$TEMP_DIR/Arch" -o "$OUT_DIR" -v | tee -a "$LOG_DIR/$DATETIME.log"

    # Cleanup
    echo "Removing temp files..."
    rm "$TEMP_DIR/Arch" -Rf | tee -a "$LOG_DIR/$DATETIME.log"

    echo "Reverting permissions..."
    chown $REAL_USER:$REAL_USER "$LIVE_DIR" -R
}

function build_full() {
    if [[ "$EUID" -eq 0 ]]; then
        echo "This section not meant to be run as root."
        echo "Aborted."
        exit 1
    fi
    
    # Prep for build
    cleanup
    fix_kit_permissions
    install_deps
    load_settings
    update_repo
    copy_archiso
    update_archlive
    # Rerun script as root to start Archiso build process
    run_elevated "$(realpath "$0")" --build-arch
}

# Check input
case $1 in
    --build-arch)
        load_settings
        build_arch
        ;;

    --copy-archiso)
        load_settings
        copy_archiso
        update_archlive
        ;;

    --fix-perms)
        fix_kit_permissions
        ;;

    --install-deps)
        install_deps
        ;;

    --update-repo)
        update_repo
        ;;
    
    *)
        build_full
        ;;
esac