feat(utils): add compare-dirs.sh utility

- recursive directory comparison based on source folder
- support for quiet mode and custom log files
- colored output and dependency checking
- integrated with main navigation table

README.md

@@ -9,6 +9,7 @@ A collection of battle-tested scripts and utilities for system administrators, D
 | OS | Stack | Utility Name | Description | Status |
 | :--- | :--- | :--- | :--- | :--- |
 | ![Windows](https://img.shields.io/badge/Windows-0078D6?style=flat-square&logo=windows&logoColor=white) | ![Batch](https://img.shields.io/badge/-Batch-4D4D4D?style=flat-square) | [AnyDesk Reset](./tools/windows/apps-reset/anydesk-id-reseter.bat) | Terminate [AnyDesk](https://anydesk.com/en) & clear config files (`ID reset`) | ✅ Stable <br> 🧰&nbsp;Built-in&nbsp; |
+| ![Linux](https://img.shields.io/badge/Linux-FCC624?style=flat-square&logo=linux&logoColor=black) | ![Bash](https://img.shields.io/badge/-Bash-4EAA25?style=flat-square) | [Directory Comparator](./tools/linux/compare-dirs/compare-dirs.sh) | Recursive file comparison between two directories with detailed diff logging | ✅ Stable <br> 🧰&nbsp;Built-in&nbsp; |
 | ![Linux](https://img.shields.io/badge/Linux-FCC624?style=flat-square&logo=linux&logoColor=black) | ![Bash](https://img.shields.io/badge/-Bash-4EAA25?style=flat-square) | [PSQL NFS Backup](https://github.com/andsyrovatko/s4k-psql-db-backuper) | Automation for [PostgreSQL](https://www.postgresql.org/) dumps with [NFS](https://en.wikipedia.org/wiki/Network_File_System) & [Telegram](https://telegram.org/) | ✅ Stable <br> 📦&nbsp;Standalone&nbsp; |
 | ![Linux](https://img.shields.io/badge/Linux-FCC624?style=flat-square&logo=linux&logoColor=black) | ![Bash](https://img.shields.io/badge/-Bash-4EAA25?style=flat-square) | [Whois Infrastructure Automator (for ISPs)](https://github.com/andsyrovatko/s4k-billing-whois-automator) | Automation for Whois DB update by billing system | ✅ Stable <br> 📦&nbsp;Standalone&nbsp; |
 | ![Linux](https://img.shields.io/badge/Linux-FCC624?style=flat-square&logo=linux&logoColor=black) | ![Bash](https://img.shields.io/badge/-Bash-4EAA25?style=flat-square) | [IP Manager for ISPs (Billing ↔ IPSET)](https://github.com/andsyrovatko/s4k-ip-manager) |  Automation IP management by billing or external system for ISPs | ✅ Stable <br> 📦&nbsp;Standalone&nbsp; |

tools/linux/compare-dirs/README.md

@@ -0,0 +1,37 @@
+# 🛠 Directory Comparator
+
+A robust Bash utility for recursive file comparison between two directories. It uses DIR_A as the source of truth for file names and checks for their existence and differences in DIR_B. Perfect for auditing configuration changes or verifying backup integrity.
+
+---
+
+### ⚙️ Prerequisites
+* **diff:** Used for generating file differences.
+* **find:** Required for recursive file discovery.
+* **Bash 4+:** Utilizes modern bash features like `set -euo pipefail`.
+
+### 📊 Parameters Mapping
+| Option | Description |
+| :--- | :--- |
+| -o <file>	| Save the full report to a specific file (default: `./compare-dirs.log`). |
+| -q	| Quiet mode: Show only the final summary without full `diff` output. |
+| -h	| Show help and usage information. |
+
+### 🏃 Quick Start
+```bash
+    # Basic comparison (outputs diffs to terminal and compare-dirs.log)
+    ./compare-dirs.sh /path/to/dir_a /path/to/dir_b
+
+    # Quiet mode (summary only) with custom log file
+    ./compare-dirs.sh -q -o audit_report.log /etc/nginx /backup/nginx
+```
+
+### 🛡 Features
+* **Safe Discovery:** Uses `-printf '%P\0'` with `find` to safely handle filenames with spaces or special characters.
+* **Strict Execution:** Built-in error trapping and strict mode to prevent silent failures.
+* **Colorized UI:** Visual feedback for **IDENTICAL**, **DIFFERENT**, and **MISSING** status.
+* **Log Rotation Ready:** Outputs to both `STDOUT` and log files simultaneously.
+
+---
+
+### ⚖️ License
+MIT [LICENSE](https://github.com/andsyrovatko/s4k-admin-toolbox/blob/main/LICENSE). Free to use and modify.

tools/linux/compare-dirs/compare-dirs.sh

@@ -0,0 +1,162 @@
+#!/usr/bin/env bash
+# =============================================================================
+# Script Name : compare-dirs.sh
+# Description : Compares files with the same names in two folders.
+#               File names are taken from the first folder (DIR_A).
+# Usage       : ./compare-dirs.sh [options] <dir_a> <dir_b>
+# Options     : -o <file>   - Save the full report to a file (instead of ./compare-dirs.log)
+#               -q          - Quiet — summary only, no diff output
+#               -h          - Show this help
+# Author      : syr4ok (Andrii Syrovatko)
+# Version     : 1.0.0
+# =============================================================================
+
+set -euo pipefail
+IFS=$'\n\t'
+
+# Configration
+LOG_FILE="./compare-dirs.log"
+QUIET=false
+
+# COLORS
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+BLUE='\033[0;34m'
+CYAN='\033[0;36m'
+BOLD='\033[1m'
+NC='\033[0m'
+
+# Logging
+log() {
+    local level="$1"; shift
+    local msg="$*"
+    local ts
+    ts=$(date '+%Y-%m-%d %H:%M:%S')
+    echo -e "${ts} [${level}] ${msg}" | tee -a "${LOG_FILE}"
+}
+log_info()  { log "INFO " "${GREEN}${*}${NC}"; }
+log_warn()  { log "WARN " "${YELLOW}${*}${NC}"; }
+log_error() { log "ERROR" "${RED}${*}${NC}"; }
+
+# Helpers
+print_header() {
+    echo -e "\n${BOLD}${BLUE}========================================${NC}"
+    echo -e "${BOLD}${BLUE}  $1${NC}"
+    echo -e "${BOLD}${BLUE}========================================${NC}\n"
+}
+
+usage() {
+    echo -e "${BOLD}Usage:${NC} $0 [options] <dir_a> <dir_b>"
+    echo ""
+    echo "  Compares files with the same names in two folders."
+    echo "  The list of files is taken from <dir_a>."
+    echo ""
+    echo "  Options:"
+    echo "    -o <file>   Save the report to the specified file"
+    echo "    -q          Summary only (no diff output)"
+    echo "    -h          Show this help"
+    exit 0
+}
+
+check_deps() {
+    for cmd in "$@"; do
+        command -v "${cmd}" &>/dev/null || { log_error "Missing dependency: ${cmd}"; exit 1; }
+    done
+}
+
+# Trap
+cleanup() {
+    local exit_code=$?
+    [[ $exit_code -ne 0 ]] && log_error "Script exited with code ${exit_code}"
+}
+trap cleanup EXIT
+
+# Argument parsing
+parse_args() {
+    while getopts ":o:qh" opt; do
+        case $opt in
+            o) LOG_FILE="${OPTARG}" ;;
+            q) QUIET=true ;;
+            h) usage ;;
+            :) echo -e "${RED}Option -${OPTARG} requires an argument.${NC}"; exit 1 ;;
+            *) echo -e "${RED}Unknown option: -${OPTARG}${NC}"; exit 1 ;;
+        esac
+    done
+    shift $((OPTIND - 1))
+
+    if [[ $# -lt 2 ]]; then
+        echo -e "${RED}Error: need to specify two folders.${NC}"
+        usage
+    fi
+
+    DIR_A="$1"
+    DIR_B="$2"
+}
+
+# --- MAIN ---
+main() {
+    parse_args "$@"
+
+    check_deps diff find
+
+    print_header "Directory Diff: compare-dirs.sh"
+    log_info "DIR_A (source of file names) : ${DIR_A}"
+    log_info "DIR_B (comparison target)    : ${DIR_B}"
+
+    # Existing check
+    [[ -d "${DIR_A}" ]] || { log_error "DIR_A does not exist: ${DIR_A}"; exit 1; }
+    [[ -d "${DIR_B}" ]] || { log_error "DIR_B does not exist: ${DIR_B}"; exit 1; }
+
+    local count_identical=0
+    local count_different=0
+    local count_missing=0
+    local total=0
+
+    # Recursively take all files from DIR_A
+    while IFS= read -r -d '' rel_file; do
+        (( total++ )) || true
+
+        file_a="${DIR_A}/${rel_file}"
+        file_b="${DIR_B}/${rel_file}"
+
+        echo -e "\n${BOLD}${CYAN}── File: ${rel_file}${NC}"
+
+        # File missing in DIR_B
+        if [[ ! -f "${file_b}" ]]; then
+            log_warn "MISSING in DIR_B: ${rel_file}"
+            (( count_missing++ )) || true
+            continue
+        fi
+
+        # Comparing files
+        if diff --color=always -u "${file_a}" "${file_b}" > /tmp/_cmp_diff_out 2>&1; then
+            log_info "IDENTICAL: ${rel_file}"
+            (( count_identical++ )) || true
+        else
+            log_warn "DIFFERENT: ${rel_file}"
+            (( count_different++ )) || true
+            # Output diff if not quiet mode
+            if [[ "${QUIET}" == false ]]; then
+                echo -e "${YELLOW}--- DIR_A/${rel_file}${NC}"
+                echo -e "${YELLOW}+++ DIR_B/${rel_file}${NC}"
+                cat /tmp/_cmp_diff_out | tee -a "${LOG_FILE}"
+            fi
+        fi
+
+    done < <(find "${DIR_A}" -type f -printf '%P\0' | sort -z)
+
+    rm -f /tmp/_cmp_diff_out
+
+    # --- STDOUT ---
+    echo ""
+    print_header "Summary"
+    echo -e "  ${BOLD}Total files checked :${NC} ${total}"
+    echo -e "  ${GREEN}Identical           : ${count_identical}${NC}"
+    echo -e "  ${RED}Different           : ${count_different}${NC}"
+    echo -e "  ${YELLOW}Missing in DIR_B    : ${count_missing}${NC}"
+    echo ""
+    log_info "Log saved to: ${LOG_FILE}"
+}
+
+main "$@"