#!/bin/bash

# Free Disk Space for Time Machine
# This script helps identify and free up space on your Mac so Time Machine can work

set -e

echo "=== Mac Disk Space Analysis ==="
echo ""

# Check current disk usage
echo "📊 Current Disk Status:"
df -h / | tail -1 | awk '{print "   Total: " $2 " | Used: " $3 " (" $5 ") | Free: " $4}'
echo ""

# Check if disk is critically low
FREE_SPACE=$(df / | tail -1 | awk '{print $4}')
FREE_SPACE_GB=$(echo "scale=2; $FREE_SPACE / 1024 / 1024" | bc)

if (( $(echo "$FREE_SPACE_GB < 5" | bc -l) )); then
    echo "⚠️  WARNING: Disk has less than 5GB free. Time Machine requires free space to work!"
    echo ""
fi

echo "🔍 Analyzing Large Files and Folders:"
echo ""

# Check Downloads folder
if [ -d ~/Downloads ]; then
    DOWNLOADS_SIZE=$(du -sh ~/Downloads 2>/dev/null | awk '{print $1}')
    echo "   📁 Downloads: $DOWNLOADS_SIZE"
fi

# Check Library Caches
if [ -d ~/Library/Caches ]; then
    CACHES_SIZE=$(du -sh ~/Library/Caches 2>/dev/null | awk '{print $1}')
    echo "   🗑️  Library/Caches: $CACHES_SIZE (safe to clean)"
fi

# Check Trash
if [ -d ~/.Trash ]; then
    TRASH_SIZE=$(du -sh ~/.Trash 2>/dev/null | awk '{print $1}')
    echo "   🗑️  Trash: $TRASH_SIZE"
fi

# Check local Time Machine snapshots
echo ""
echo "📸 Local Time Machine Snapshots:"
SNAPSHOTS=$(tmutil listlocalsnapshots / 2>/dev/null | grep -v "Snapshots for disk" | grep -v "^$" | wc -l | tr -d ' ')
if [ "$SNAPSHOTS" -gt 0 ]; then
    echo "   Found $SNAPSHOTS local snapshot(s)"
    tmutil listlocalsnapshots / 2>/dev/null | grep -v "Snapshots for disk" | grep -v "^$" | sed 's/^/   - /'
    echo ""
    echo "   💡 Tip: Local snapshots are automatically deleted when space is needed,"
    echo "      but you can delete them manually if needed."
else
    echo "   No local snapshots found"
fi

echo ""
echo "📋 Top 10 Largest Files/Directories in Home:"
du -h -d 1 ~ 2>/dev/null | sort -hr | head -10 | awk '{printf "   %8s  %s\n", $1, $2}'

echo ""
echo "=== Recommendations ==="
echo ""
echo "1. 🗑️  Empty Trash:"
echo "   rm -rf ~/.Trash/*"
echo ""
echo "2. 🧹 Clean System Caches (safe):"
echo "   rm -rf ~/Library/Caches/*"
echo ""
echo "3. 📁 Review Downloads folder (~/Downloads) - 19GB found"
echo "   Move large files to NAS or delete if not needed"
echo ""
echo "4. 🗑️  Delete old local snapshots (if needed):"
echo "   sudo tmutil deletelocalsnapshots <snapshot-date>"
echo ""
echo "5. 💾 Use Storage Management:"
echo "   Apple Menu → About This Mac → Storage → Manage"
echo "   This tool can help identify and remove large files, old backups, etc."
echo ""
echo "6. 📦 Check for large applications:"
echo "   Review Applications folder for unused apps"
echo ""
echo "=== Quick Clean Commands ==="
echo ""
echo "To clean caches (safe, will regenerate):"
echo "  rm -rf ~/Library/Caches/*"
echo ""
echo "To empty trash:"
echo "  rm -rf ~/.Trash/*"
echo ""
echo "To see what's taking up space:"
echo "  du -h -d 1 ~ | sort -hr | head -20"
echo ""