#!/usr/bin/env bash

set -euo pipefail

BASE_URL="https://bash.gejodel.de"
ALIASES_URL="${BASE_URL}/bash_aliases"

BASHRC="${HOME}/.bashrc"
ALIASES="${HOME}/.bash_aliases"
BACKUP_DIR="${HOME}/.bash-backups"

PACKAGES=(
    htop
    screen
    mc
)

echo
echo "=========================================="
echo " Bash-Setup für ${USER:-$(whoami)}"
echo "=========================================="
echo

# ------------------------------------------------------------
# Root / sudo vorbereiten
# ------------------------------------------------------------

if [ "$(id -u)" -eq 0 ]; then
    SUDO=""
    echo "==> Läuft als root - sudo nicht erforderlich"
else
    if ! command -v sudo >/dev/null 2>&1; then
        echo "FEHLER: sudo ist nicht installiert."
        echo "Bitte als root ausführen oder sudo installieren."
        exit 1
    fi

    SUDO="sudo"

    echo "==> Benötige einmalig sudo-Berechtigung..."
    sudo -v

    # sudo-Timestamp während der Installation gültig halten
    (
        while true; do
            sudo -n true 2>/dev/null || exit
            sleep 50
        done
    ) &

    SUDO_KEEPALIVE_PID=$!

    cleanup_sudo() {
        kill "$SUDO_KEEPALIVE_PID" 2>/dev/null || true
    }

    trap cleanup_sudo EXIT
fi

echo

# ------------------------------------------------------------
# Download-Helfer
# ------------------------------------------------------------

download() {
    local url="$1"
    local destination="$2"

    if command -v curl >/dev/null 2>&1; then
        curl -fsSL "$url" -o "$destination"
    elif command -v wget >/dev/null 2>&1; then
        wget -q "$url" -O "$destination"
    else
        echo "FEHLER: Weder curl noch wget gefunden."
        exit 1
    fi
}

# ------------------------------------------------------------
# Backup
# ------------------------------------------------------------

mkdir -p "$BACKUP_DIR"

TIMESTAMP="$(date '+%Y%m%d-%H%M%S')"

if [ -f "$BASHRC" ]; then
    cp -p "$BASHRC" "${BACKUP_DIR}/bashrc.${TIMESTAMP}"
    echo "==> Backup: ${BACKUP_DIR}/bashrc.${TIMESTAMP}"
fi

if [ -f "$ALIASES" ]; then
    cp -p "$ALIASES" "${BACKUP_DIR}/bash_aliases.${TIMESTAMP}"
    echo "==> Backup: ${BACKUP_DIR}/bash_aliases.${TIMESTAMP}"
fi

# ------------------------------------------------------------
# .bash_aliases herunterladen
# ------------------------------------------------------------

TMP_ALIASES="$(mktemp)"

cleanup_tmp() {
    rm -f "$TMP_ALIASES"

    if [ -n "${SUDO_KEEPALIVE_PID:-}" ]; then
        kill "$SUDO_KEEPALIVE_PID" 2>/dev/null || true
    fi
}

trap cleanup_tmp EXIT

echo
echo "==> Lade .bash_aliases herunter..."

download "$ALIASES_URL" "$TMP_ALIASES"

if [ ! -s "$TMP_ALIASES" ]; then
    echo "FEHLER: Heruntergeladene .bash_aliases ist leer."
    exit 1
fi

mv "$TMP_ALIASES" "$ALIASES"
chmod 644 "$ALIASES"

echo "==> .bash_aliases installiert"

# ------------------------------------------------------------
# .bashrc sicherstellen
# ------------------------------------------------------------

if [ ! -f "$BASHRC" ]; then
    touch "$BASHRC"
fi

# ------------------------------------------------------------
# force_color_prompt=yes aktivieren
# ------------------------------------------------------------

echo
echo "==> Prüfe farbigen Bash-Prompt..."

if grep -Eq '^[[:space:]]*#[[:space:]]*force_color_prompt=yes[[:space:]]*$' "$BASHRC"; then

    sed -i -E \
        's/^[[:space:]]*#[[:space:]]*force_color_prompt=yes[[:space:]]*$/force_color_prompt=yes/' \
        "$BASHRC"

    echo "==> force_color_prompt=yes aktiviert"

elif grep -Eq '^[[:space:]]*force_color_prompt=yes[[:space:]]*$' "$BASHRC"; then

    echo "==> force_color_prompt=yes ist bereits aktiviert"

else

    echo "==> Hinweis: force_color_prompt=yes wurde in .bashrc nicht gefunden"

fi

# ------------------------------------------------------------
# Sicherstellen, dass ~/.bash_aliases geladen wird
# ------------------------------------------------------------

if ! grep -Eq '(^|[[:space:]])(\.|source)[[:space:]]+.*\.bash_aliases' "$BASHRC"; then

    echo "==> Ergänze .bash_aliases-Loader in .bashrc"

    cat >> "$BASHRC" <<'EOF'

# ~/.bash_aliases laden
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi
EOF

else

    echo "==> .bash_aliases wird bereits von .bashrc geladen"

fi

# ------------------------------------------------------------
# Konfiguration für diesen Script-Prozess laden
# ------------------------------------------------------------

echo
echo "==> Lade Bash-Konfiguration..."

# shellcheck disable=SC1090
source "$BASHRC" || true

echo "==> Bash-Konfiguration geladen"

# ------------------------------------------------------------
# Pakete installieren
# ------------------------------------------------------------

echo
echo "==> Aktualisiere Paketlisten..."

$SUDO apt-get update

echo
echo "==> Installiere Pakete: ${PACKAGES[*]}"

$SUDO apt-get install -y "${PACKAGES[@]}"

# ------------------------------------------------------------
# Fertig
# ------------------------------------------------------------

echo
echo "=========================================="
echo " Setup erfolgreich abgeschlossen"
echo "=========================================="
echo
echo "Installiert:"
echo "  - .bash_aliases"
echo "  - force_color_prompt=yes"
echo "  - htop"
echo "  - screen"
echo "  - mc"
echo
echo "Die Bash-Konfiguration ist für neue Shells"
echo "automatisch aktiv."
echo
echo "Für die aktuell geöffnete Shell einmal:"
echo
echo "  source ~/.bashrc"
echo