#!/bin/bash

WATCH_DIR="$1"
DURATION="${2:-300}"   # Standard: 300 Sekunden (5 min)
TARGET_GB=80

if [ -z "$WATCH_DIR" ]; then
    echo "Usage: $0 /pfad/zum/ordner [dauer_in_sekunden]"
    exit 1
fi

if [ ! -d "$WATCH_DIR" ]; then
    echo "Fehler: Ordner '$WATCH_DIR' existiert nicht."
    exit 1
fi

echo "Überwache Ordner: $WATCH_DIR"
echo "Dauer: $DURATION Sekunden"
echo

initial_size=$(du -sb "$WATCH_DIR" | awk '{print $1}')
start_time=$(date +%s)

echo "Live-Überwachung gestartet..."
echo

# Fortschrittsbalken + Live-Statistik
for ((i=0; i<DURATION; i++)); do
    current_size=$(du -sb "$WATCH_DIR" | awk '{print $1}')
    diff=$((current_size - initial_size))

    # Formatierte Größen
    diff_fmt=$(numfmt --to=iec $diff)
    curr_fmt=$(numfmt --to=iec $current_size)

    # Fortschritt
    progress=$(( (i * 100) / DURATION ))
    bar_len=$((progress / 2))
    bar=$(printf "%${bar_len}s" | tr " " "#")

    printf "\r[% -50s] %3d%% | Gesamt: %s | Zuwachs: %s" "$bar" "$progress" "$curr_fmt" "$diff_fmt"
    sleep 1
done

echo
echo "Überwachung abgeschlossen."
echo

final_size=$(du -sb "$WATCH_DIR" | awk '{print $1}')
bytes_copied=$((final_size - initial_size))

if [ "$bytes_copied" -le 0 ]; then
    echo "⚠ Keine neuen Daten gefunden."
    exit 0
fi

rate=$(echo "$bytes_copied / $DURATION" | bc -l)
target_bytes=$(echo "$TARGET_GB * 1024 * 1024 * 1024" | bc)
seconds_needed=$(echo "$target_bytes / $rate" | bc -l)

hours=$(printf "%.1f" "$(echo "$seconds_needed / 3600" | bc -l)")
minutes=$(printf "%.0f" "$(echo "$seconds_needed / 60" | bc -l)")

echo "-------------------------------------------"
echo "Zusammenfassung:"
echo "Neue Daten: $(numfmt --to=iec $bytes_copied)"
echo "Durchsatz:  $(numfmt --to=iec $rate)/s"
echo
echo "Zeit für $TARGET_GB GB:"
echo "  ≈ $hours Stunden"
echo "  oder ≈ $minutes Minuten"
echo "-------------------------------------------"