#!/bin/bash

# Clean Time Machine System Files
# This script safely removes Time Machine files from system locations

set -e

echo "=== Time Machine System Files Cleanup ==="
echo ""
echo "⚠️  WARNING: This script will delete Time Machine system files."
echo "   Make sure you understand what will be deleted."
echo ""

# Check current free space
FREE_SPACE_BEFORE=$(df / | tail -1 | awk '{print $4}')
FREE_SPACE_GB_BEFORE=$(echo "scale=2; $FREE_SPACE_BEFORE / 1024 / 1024" | bc)
echo "Current free space: ${FREE_SPACE_GB_BEFORE}GB"
echo ""

# Ask for confirmation
read -p "Do you want to proceed? This will delete Time Machine system files. (yes/no) " -r
echo ""
if [[ ! $REPLY =~ ^[Yy][Ee][Ss]$ ]]; then
    echo "Cancelled."
    exit 0
fi

echo ""
echo "🧹 Cleaning Time Machine system files..."
echo ""

FREED_TOTAL=0

# 1. Delete local snapshots
echo "1. Deleting local snapshots..."
SNAPSHOTS=$(tmutil listlocalsnapshots / 2>/dev/null | grep -v "Snapshots for disk" | grep -v "^$")
if [ -n "$SNAPSHOTS" ]; then
    echo "$SNAPSHOTS" | while read snapshot; do
        if [ -n "$snapshot" ]; then
            echo "   Deleting snapshot: $snapshot"
            sudo tmutil deletelocalsnapshots "$snapshot" 2>/dev/null || {
                echo "   ⚠️  Could not delete $snapshot (may require different method)"
            }
        fi
    done
    echo "   ✓ Local snapshots deleted"
else
    echo "   ✓ No local snapshots to delete"
fi
echo ""

# 2. Disable local snapshots temporarily (they'll recreate but this helps)
echo "2. Disabling local snapshots (to prevent immediate recreation)..."
sudo tmutil disablelocal 2>/dev/null || echo "   ⚠️  Could not disable local snapshots"
echo ""

# 3. Clean MobileBackups (if they exist and are safe to remove)
echo "3. Checking MobileBackups..."
if [ -d "/.MobileBackups" ] || [ -d "/System/Volumes/Data/.MobileBackups" ]; then
    echo "   ⚠️  MobileBackups directory found."
    echo "   These are APFS snapshots. They're usually managed automatically."
    echo "   Deleting them manually can cause issues."
    echo "   Recommendation: Let macOS manage these automatically."
    echo "   They will be deleted when space is needed."
    read -p "   Do you want to try deleting MobileBackups? (yes/no) " -r
    if [[ $REPLY =~ ^[Yy][Ee][Ss]$ ]]; then
        if [ -d "/.MobileBackups" ]; then
            echo "   Attempting to delete /.MobileBackups..."
            sudo rm -rf /.MobileBackups/* 2>/dev/null || echo "   ⚠️  Could not delete (may be in use)"
        fi
        if [ -d "/System/Volumes/Data/.MobileBackups" ]; then
            echo "   Attempting to delete /System/Volumes/Data/.MobileBackups..."
            sudo rm -rf /System/Volumes/Data/.MobileBackups/* 2>/dev/null || echo "   ⚠️  Could not delete (may be in use)"
        fi
    fi
else
    echo "   ✓ No MobileBackups directory found"
fi
echo ""

# 4. Find and remove orphaned sparse bundles
echo "4. Searching for orphaned Time Machine sparse bundles..."
find /private/var -name "*.sparsebundle" -o -name "*.sparseimage" 2>/dev/null | while read bundle; do
    if [ -e "$bundle" ]; then
        SIZE=$(sudo du -sh "$bundle" 2>/dev/null | awk '{print $1}')
        echo "   Found: $bundle ($SIZE)"
        read -p "   Delete this bundle? (yes/no) " -r
        if [[ $REPLY =~ ^[Yy][Ee][Ss]$ ]]; then
            sudo rm -rf "$bundle" 2>/dev/null && echo "   ✓ Deleted" || echo "   ⚠️  Could not delete"
        fi
    fi
done
echo ""

# 5. Clean Time Machine logs (safe, will regenerate)
echo "5. Cleaning Time Machine logs..."
sudo rm -rf /private/var/log/com.apple.TimeMachine* 2>/dev/null || true
echo "   ✓ Logs cleaned"
echo ""

# 6. Re-enable local snapshots (they're useful, just need space first)
echo "6. Re-enabling local snapshots..."
sudo tmutil enablelocal 2>/dev/null || echo "   ⚠️  Could not re-enable (may already be enabled)"
echo ""

# Check new free space
FREE_SPACE_AFTER=$(df / | tail -1 | awk '{print $4}')
FREE_SPACE_GB_AFTER=$(echo "scale=2; $FREE_SPACE_AFTER / 1024 / 1024" | bc)
FREED_GB=$(echo "scale=2; $FREE_SPACE_GB_AFTER - $FREE_SPACE_GB_BEFORE" | bc)

echo ""
echo "=== Results ==="
echo "   Before: ${FREE_SPACE_GB_BEFORE}GB free"
echo "   After:  ${FREE_SPACE_GB_AFTER}GB free"
if (( $(echo "$FREED_GB > 0" | bc -l) )); then
    echo "   Freed: ${FREED_GB}GB"
else
    echo "   Freed: 0GB (files may be in use or protected)"
fi
echo ""

if (( $(echo "$FREE_SPACE_GB_AFTER < 10" | bc -l) )); then
    echo "⚠️  Still low on space. The 100GB+ may be in a protected location."
    echo ""
    echo "Next steps:"
    echo "1. Check macOS Storage Management:"
    echo "   Apple Menu → About This Mac → Storage → Manage"
    echo "   Look for 'System Files' and see what's taking space"
    echo ""
    echo "2. The files may be APFS snapshots that need special handling:"
    echo "   sudo tmutil listlocalsnapshots /"
    echo "   # Then delete each one:"
    echo "   sudo tmutil deletelocalsnapshots <snapshot-name>"
    echo ""
    echo "3. Check for large files in system locations:"
    echo "   sudo du -h -d 1 /System/Volumes/Data | sort -hr | head -20"
    echo ""
else
    echo "✅ Good! You should have enough space for Time Machine now."
fi

echo ""