update-system.sh

#!/bin/bash
#
# update-system.sh
# -----------------
# A modular, extensible system maintenance script for Debian/Ubuntu.
#
# Features:
#   - Update, upgrade, dist-upgrade, cleanup
#   - System info summary (OS, kernel, disk, memory)
#   - Package health check
#   - Verbose/quiet modes with color-coded output
#   - Per-run log files in /var/log/update-system/
#   - Log rotation: keeps last 10 runs
#   - Summary report (packages upgraded, warnings, errors)
#
# Usage:
#   sudo ./update-system.sh --full --verbose
#
# Author: Vikram (https://github.com/vikram2327)
# License: MIT
# ---------------------------------------------------------------------

set -euo pipefail

# ---------------------------------------------------------------------
# CONFIGURATION
# ---------------------------------------------------------------------

LOGDIR="/var/log/update-system"
mkdir -p "$LOGDIR"

# Unique log file per run
LOGFILE="$LOGDIR/update-system-$(date '+%Y-%m-%d-%H-%M-%S').log"

# Keep last 10 logs
MAX_LOGS=10

VERBOSE=false

# Counters for summary
ERROR_COUNT=0
WARNING_COUNT=0
UPGRADE_COUNT=0

# Colors for screen output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
WHITE='\033[0;37m'
NC='\033[0m' # No Color

# Track run time
START_TIME=$(date +%s)

# ---------------------------------------------------------------------
# LOGGING FUNCTIONS
# ---------------------------------------------------------------------

rotate_logs() {
    # Keep only the latest MAX_LOGS files
    local FILES
    FILES=($(ls -t "$LOGDIR"/update-system-*.log 2>/dev/null || true))
    local COUNT=${#FILES[@]}

    if (( COUNT > MAX_LOGS )); then
        for ((i=MAX_LOGS; i<COUNT; i++)); do
            rm -f "${FILES[$i]}"
        done
    fi
}

log() {
    local LEVEL="$1"
    local MSG="$2"
    local TIMESTAMP="[$(date '+%Y-%m-%d %H:%M:%S')]"

    # Count warnings and errors
    case "$LEVEL" in
        WARNING) ((WARNING_COUNT++)) ;;
        ERROR)   ((ERROR_COUNT++)) ;;
    esac

    # Pick color based on level
    case "$LEVEL" in
        INFO) COLOR=$BLUE ;;
        SUCCESS) COLOR=$GREEN ;;
        WARNING) COLOR=$YELLOW ;;
        ERROR) COLOR=$RED ;;
        *) COLOR=$NC ;;
    esac

    # Print to screen (colored)
    echo -e "${COLOR}${TIMESTAMP} [$LEVEL] ${MSG}${NC}"

    # Save plain text to log file
    echo "${TIMESTAMP} [$LEVEL] ${MSG}" >> "$LOGFILE"
}

run_cmd() {
    # Execute a command with color-coded output
    local CMD="$1"

    if [ "$VERBOSE" = true ]; then
        {
            eval "$CMD" 2> >(while read -r line; do 
                echo -e "${RED}[stderr] $line${NC}" | tee -a "$LOGFILE"
            done) | while read -r line; do
                echo -e "${WHITE}$line${NC}" | tee -a "$LOGFILE"
            done
        }
    else
        eval "$CMD" >> "$LOGFILE" 2>&1
    fi
}

# ---------------------------------------------------------------------
# CORE FUNCTIONS
# ---------------------------------------------------------------------

system_info() {
    log INFO "Collecting system information..."
    {
        echo "===== SYSTEM INFO ====="
        uname -a
        lsb_release -a 2>/dev/null || true
        echo "Memory Usage:"
        free -h
        echo "Disk Usage:"
        df -h /
        echo "======================="
    } | tee -a "$LOGFILE"
}

check_broken() {
    log INFO "Checking for broken dependencies..."
    run_cmd "sudo apt-get check"
}

update() {
    log INFO "Updating package index..."
    run_cmd "sudo apt-get update -y"
}

upgrade() {
    log INFO "Upgrading installed packages..."
    local OUTPUT
    OUTPUT=$(sudo apt-get upgrade -y --fix-missing 2>&1)
    echo "$OUTPUT" >> "$LOGFILE"
    [ "$VERBOSE" = true ] && echo -e "${WHITE}$OUTPUT${NC}"

    local COUNT=$(echo "$OUTPUT" | grep -oP '^\d+ upgraded' | awk '{print $1}' || echo 0)
    UPGRADE_COUNT=$((UPGRADE_COUNT + COUNT))
}

dist_upgrade() {
    log INFO "Performing full dist-upgrade..."
    local OUTPUT
    OUTPUT=$(sudo apt-get dist-upgrade -y 2>&1)
    echo "$OUTPUT" >> "$LOGFILE"
    [ "$VERBOSE" = true ] && echo -e "${WHITE}$OUTPUT${NC}"

    local COUNT=$(echo "$OUTPUT" | grep -oP '^\d+ upgraded' | awk '{print $1}' || echo 0)
    UPGRADE_COUNT=$((UPGRADE_COUNT + COUNT))
}

cleanup() {
    log INFO "Removing unused packages..."
    run_cmd "sudo apt-get autoremove -y"
    log INFO "Cleaning package cache..."
    run_cmd "sudo apt-get autoclean -y"
    run_cmd "sudo apt-get clean -y"
}

full() {
    system_info
    check_broken
    update
    upgrade
    dist_upgrade
    cleanup
    log SUCCESS "System fully updated and cleaned."
}

# ---------------------------------------------------------------------
# USAGE & HELP
# ---------------------------------------------------------------------

usage() {
    echo "Usage: $0 [OPTIONS]"
    echo
    echo "Options:"
    echo "  --update         Refresh package index"
    echo "  --upgrade        Upgrade installed packages"
    echo "  --dist-upgrade   Perform full upgrade (kernel, dependencies)"
    echo "  --cleanup        Remove old/unused packages and cache"
    echo "  --system-info    Show system info summary"
    echo "  --check          Check for broken dependencies"
    echo "  --full           Run all steps (system-info, check, update, upgrade, dist-upgrade, cleanup)"
    echo "  --verbose        Show full command output in terminal"
    echo "  --quiet          Only log to file (default)"
    exit 1
}

# ---------------------------------------------------------------------
# SCRIPT START
# ---------------------------------------------------------------------

rotate_logs

log INFO "===== Update Script Started ====="
log INFO "User     : $(whoami)"
log INFO "Hostname : $(hostname)"
log INFO "Date     : $(date '+%Y-%m-%d %H:%M:%S')"
log INFO "Flags    : $*"

# If no arguments, show usage
if [ $# -eq 0 ]; then
    usage
fi

# Parse flags
for arg in "$@"; do
    case "$arg" in
        --update) update ;;
        --upgrade) upgrade ;;
        --dist-upgrade) dist_upgrade ;;
        --cleanup) cleanup ;;
        --system-info) system_info ;;
        --check) check_broken ;;
        --full) full ;;
        --verbose) VERBOSE=true ;;
        --quiet) VERBOSE=false ;;
        *) usage ;;
    esac
done

# ---------------------------------------------------------------------
# SUMMARY & END
# ---------------------------------------------------------------------

EXIT_CODE=$?
END_TIME=$(date +%s)
DURATION=$((END_TIME - START_TIME))

if [ $EXIT_CODE -eq 0 ] && [ $ERROR_COUNT -eq 0 ]; then
    log SUCCESS "===== Update Script Completed Successfully ====="
else
    log ERROR "===== Update Script Failed (Exit Code: $EXIT_CODE) ====="
fi

log INFO "End Date : $(date '+%Y-%m-%d %H:%M:%S')"
log INFO "Duration : ${DURATION} seconds"

# Summary Report
log INFO "===== Summary Report ====="
log INFO "Packages Upgraded : $UPGRADE_COUNT"
log WARNING "Warnings          : $WARNING_COUNT"
log ERROR "Errors            : $ERROR_COUNT"

if [ $EXIT_CODE -eq 0 ] && [ $ERROR_COUNT -eq 0 ]; then
    log SUCCESS "Run completed successfully with no errors."
else
    log ERROR "Run completed with issues. Check the log file: $LOGFILE"
fi