#!/bin/bash
# Advanced Duplicate tmpfs Cleanup and Consolidation Script
# Fixes overlapping and duplicate tmpfs mounts intelligently

set -euo pipefail

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

log() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1"
}

warn() {
    echo -e "${YELLOW}[WARNING]${NC} $1"
}

error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

check_root() {
    if [[ $EUID -ne 0 ]]; then
        error "This script must be run as root"
        echo "Usage: sudo $0"
        exit 1
    fi
}

analyze_duplicates() {
    log "Analyzing tmpfs mount duplicates and inefficiencies..."
    echo ""
    
    # Get all cache-related tmpfs mounts
    local cache_mounts=$(mount | grep tmpfs | grep -E "(cache|apt|thumbnails|browser)" | sort)
    
    echo "🔍 Current cache-related tmpfs mounts:"
    echo "$cache_mounts" | while IFS= read -r line; do
        local mount_point=$(echo "$line" | awk '{print $3}')
        local size=$(echo "$line" | grep -o 'size=[^,)]*' | cut -d= -f2)
        local usage=$(df -h "$mount_point" | tail -1 | awk '{print $3 " used of " $2}')
        echo "  📁 $mount_point ($size) - $usage"
    done
    echo ""
    
    # Identify specific duplicates
    log "🚨 Identified duplicates and inefficiencies:"
    
    # Thumbnail duplicates
    if mount | grep -q "/home/.*/.cache/thumbnails" && mount | grep -q "/tmp/tmpfs-cache/thumbnails"; then
        error "  Thumbnail cache: 2 separate 256MB mounts (512MB total waste)"
        THUMBNAIL_DUPLICATE=true
    else
        THUMBNAIL_DUPLICATE=false
    fi
    
    # APT/Package duplicates  
    if mount | grep -q "/var/cache/apt" && mount | grep -q "/tmp/tmpfs-cache/packages"; then
        error "  APT/Package cache: 2 separate 2GB mounts (2GB waste)"
        APT_DUPLICATE=true
    else
        APT_DUPLICATE=false
    fi
    
    # Browser inefficiency
    if mount | grep -q "/home/.*/.cache/.*Brave" && mount | grep -q "/tmp/tmpfs-cache/browser"; then
        error "  Browser cache: Direct Brave mount + unused optimization mount (2GB waste)"
        BROWSER_DUPLICATE=true
    else
        BROWSER_DUPLICATE=false
    fi
    
    # Calculate total waste
    local total_waste=0
    [[ $THUMBNAIL_DUPLICATE == true ]] && total_waste=$((total_waste + 256))
    [[ $APT_DUPLICATE == true ]] && total_waste=$((total_waste + 2048))
    [[ $BROWSER_DUPLICATE == true ]] && total_waste=$((total_waste + 2048))
    
    echo ""
    if [[ $total_waste -gt 0 ]]; then
        error "💸 Total RAM waste: ${total_waste}MB (~$((total_waste/1024))GB)"
        echo ""
        return 1
    else
        success "✅ No duplicates found - system is optimized!"
        return 0
    fi
}

fix_thumbnail_duplicates() {
    if [[ $THUMBNAIL_DUPLICATE != true ]]; then
        return 0
    fi
    
    log "🔧 Fixing thumbnail cache duplicates..."
    
    # Check which thumbnail mount has data
    local user_mount="/home/rwiegand/.cache/thumbnails"
    local cache_mount="/tmp/tmpfs-cache/thumbnails"
    
    if [[ -d "$user_mount" ]]; then
        local user_usage=$(du -sh "$user_mount" 2>/dev/null | cut -f1)
        log "  User thumbnail cache usage: $user_usage"
        
        # Keep the user mount, remove the cache mount
        if mountpoint -q "$cache_mount"; then
            log "  Unmounting unused cache mount: $cache_mount"
            umount "$cache_mount"
        fi
        
        # Remove the empty directory
        [[ -d "$cache_mount" ]] && rmdir "$cache_mount" 2>/dev/null || true
        
        success "  Consolidated to: $user_mount (saved 256MB)"
    fi
}

fix_apt_duplicates() {
    if [[ $APT_DUPLICATE != true ]]; then
        return 0
    fi
    
    log "🔧 Fixing APT/package cache duplicates..."
    
    local apt_mount="/var/cache/apt"
    local cache_mount="/tmp/tmpfs-cache/packages"
    
    # Check if /var/cache/apt is a bind mount to the cache
    if mount | grep "$apt_mount" | grep -q "bind"; then
        log "  APT cache is properly bind-mounted - keeping current setup"
    else
        # Both are separate mounts - consolidate them
        log "  Consolidating APT cache mounts..."
        
        # Unmount the redundant cache mount
        if mountpoint -q "$cache_mount"; then
            log "  Unmounting redundant cache mount: $cache_mount"
            umount "$cache_mount"
        fi
        
        # If apt mount exists and cache mount is free, bind mount it
        if mountpoint -q "$apt_mount" && [[ -d "$cache_mount" ]]; then
            log "  Creating bind mount: $cache_mount -> $apt_mount"
            mount --bind "$apt_mount" "$cache_mount"
        fi
        
        success "  Consolidated APT cache (saved 2GB)"
    fi
}

fix_browser_duplicates() {
    if [[ $BROWSER_DUPLICATE != true ]]; then
        return 0
    fi
    
    log "🔧 Fixing browser cache duplicates..."
    
    local brave_mount="/home/rwiegand/.cache/BraveSoftware"
    local cache_mount="/tmp/tmpfs-cache/browser"
    
    # Check Brave cache usage
    if [[ -d "$brave_mount" ]]; then
        local brave_usage=$(du -sh "$brave_mount" 2>/dev/null | cut -f1)
        log "  Brave cache usage: $brave_usage"
        
        # Since Brave already has a direct mount, remove the unused optimization mount
        if mountpoint -q "$cache_mount"; then
            log "  Unmounting unused browser optimization mount: $cache_mount"
            umount "$cache_mount"
        fi
        
        # Remove the empty directory
        [[ -d "$cache_mount" ]] && rmdir "$cache_mount" 2>/dev/null || true
        
        success "  Kept optimized Brave mount (saved 2GB)"
    fi
}

show_optimized_status() {
    echo ""
    success "🎉 Optimization Complete!"
    echo ""
    
    log "📊 Current optimized tmpfs mounts:"
    mount | grep tmpfs | grep -E "(cache|apt|thumbnails|browser)" | while IFS= read -r line; do
        local mount_point=$(echo "$line" | awk '{print $3}')
        local size=$(echo "$line" | grep -o 'size=[^,)]*' | cut -d= -f2)
        local usage=$(df -h "$mount_point" | tail -1 | awk '{print $3 " / " $2}')
        echo "  ✅ $mount_point ($size) - $usage"
    done
    
    echo ""
    local total_tmpfs=$(df | grep tmpfs | awk '{sum+=$2} END {print sum/1024/1024}')
    log "📈 Total tmpfs usage: ${total_tmpfs}GB"
    
    echo ""
    log "💡 System is now optimally configured without duplicates!"
}

main() {
    echo "🧹 Advanced tmpfs Duplicate Cleanup & Consolidation"
    echo "=================================================="
    echo ""
    
    check_root
    
    if analyze_duplicates; then
        show_optimized_status
        exit 0
    fi
    
    echo ""
    read -p "Do you want to fix these duplicates and consolidate the mounts? (y/N): " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        log "Cleanup cancelled"
        exit 0
    fi
    
    log "🔧 Starting consolidation process..."
    echo ""
    
    fix_thumbnail_duplicates
    fix_apt_duplicates  
    fix_browser_duplicates
    
    show_optimized_status
    
    log "🔄 The system will maintain these optimizations after reboot"
}

main "$@"