Compare local config files/folders against two Dropbox references and show concise diffs/missing files

bash_rc_reseync_v3.sh

#!/usr/bin/env bash
# SPDX-License-Identifier: MIT
# SPDX-FileCopyrightText: 2025 dzogrim
# SPDX-FileContributor: dzogrim <[email protected]>
# ==============================================================================
# Compare local config files/folders against two Dropbox references
#      ("work" and "personal") and show concise diffs/missing files.
# ==============================================================================
# How it works
#   • The REFSETS array lists triplets: "current|ref_work|ref_personal".
#   • The current runtime "environment" is inferred from $LOGNAME
#   • For each triplet:
#       1) Select the primary reference based on the environment,
#          and the other becomes the secondary.
#       2) For each file in "current":
#            - If the reference is a folder, compare matching basenames.
#            - If the reference is a file, compare that file directly.
#            - Print a short unified diff (context 1) when content differs.
#            - Report when a file is missing from the reference.
#
# A special handling for git user
#   • When comparing ".gitconfig", the whole `[user]` section is ignored
#     (from `[user]` up to the next section header) on both sides so that
#     personal identity settings do not trigger false positives.
#
# Dependencies:
#   • `jq`, `gdiff`, `gawk` and Dropbox desktop for macOS
#
# Configuration
#   • REFSETS: add lines for new (current|work|personal) sets.
#   • BLACKLIST: basenames to skip (supports shell globs).
#   • LOGNAME: environment mapping is defined in the case/esac below.
#
# Notes
#   • Adjust REFSETS and BLACKLIST to your setup.
#   • Adjust LOGNAME to your environments.
#   • The script is read-only: it never mutates files, only compares.
#   • Designed to be concise in output for regular audits.
# ==============================================================================

set -euo pipefail

# Resolve Dropbox personal root from Dropbox info.json
dropboxDir="$(jq -r '.personal.path' <"${HOME}/.dropbox/info.json")"

# REFSETS: triplets "current|ref_work|ref_personal"
REFSETS=(
  "${HOME}/.bashrc.d|${dropboxDir}/Private/_SyncThat/.dotfiles_work/.bashrc.d|${dropboxDir}/Private/_SyncThat/.dotfiles/.bashrc.d"
  "${HOME}/.config/nix|${dropboxDir}/Private/_SyncThat/.dotfiles_work/.config/nix|${dropboxDir}/Private/_SyncThat/.dotfiles/.config/nix"
)
# Repositories to audit at a single-file level (not as directories)
REFSETS+=(
  "${HOME}/.gitconfig|${dropboxDir}/Private/_SyncThat/.dotfiles_work/.gitconfig|${dropboxDir}/Private/_SyncThat/.dotfiles/.gitconfig"
  "${HOME}/.gitignore_global|${dropboxDir}/Private/_SyncThat/.dotfiles_work/.gitignore_global|${dropboxDir}/Private/_SyncThat/.dotfiles/.gitignore_global"
)

# Files to ignore (shell globs allowed)
BLACKLIST=(
  'flake.lock'
  'registry.json'
)

# Environment detection from $LOGNAME  → sets primary/secondary
case "${LOGNAME}" in
  user.name) current_env="pro"    ;;
  nickname) current_env="perso"  ;;
  *) echo "❌ Environment not recognized for user ${LOGNAME}"; exit 1 ;;
esac

# is_blacklisted <basename>
# Returns 0 if the file should be skipped, 1 otherwise
is_blacklisted() {
  local name="$1"
  for pat in "${BLACKLIST[@]}"; do
    [[ "$name" == "$pat" ]] && return 0
  done
  return 1
}

# ------------------------------------------------------------------------------
# audit_against <current_path> <reference_path> <label>
# Compares each file in <current_path> against <reference_path>
# ------------------------------------------------------------------------------
audit_against() {
  local current="$1" reference="$2" label="$3"

  # 1) Build the list of files from "current"
  local -a files=()
  if [[ -f "$current" ]]; then
    files=("$current")
  elif [[ -d "$current" ]]; then
    mapfile -t files < <(find "$current" -maxdepth 1 -type f ! -name '.DS_Store')
  else
    echo "❌ Path not found: $current"
    return
  fi

  # 2) Compare each file against its reference (directory OR file)
  for f in "${files[@]}"; do
    local base ref_file
    base="$(basename "$f")"
    is_blacklisted "$base" && continue

    if [[ -d "$reference" ]]; then
      # référence = directory
      ref_file="${reference%/}/${base}"
    else
      # reference = file
      ref_file="$reference"
    fi

    if [[ -f "$ref_file" ]]; then
      if [[ "$base" == ".gitconfig" ]]; then
        # Ignore the [user] section when comparing .gitconfig
        if ! diff -q \
             <(awk 'BEGIN{s=0} /^\[user\]/{s=1; next} /^\[/{s=0} s==0{print}' "$f") \
             <(awk 'BEGIN{s=0} /^\[user\]/{s=1; next} /^\[/{s=0} s==0{print}' "$ref_file") >/dev/null; then
          echo -e "\n⚠️ ${base} differs from ${label} backup:"
          { diff -u -1 \
                <(awk 'BEGIN{s=0} /^\[user\]/{s=1; next} /^\[/{s=0} s==0{print}' "$ref_file") \
                <(awk 'BEGIN{s=0} /^\[user\]/{s=1; next} /^\[/{s=0} s==0{print}' "$f") || true; } | sed 's/^/   /'
        fi
      else
        if ! diff -q "$f" "$ref_file" >/dev/null; then
          echo -e "\n⚠️ ${base} differs from ${label} backup:"
          { diff -u -1 "$ref_file" "$f" || true; } | sed 's/^/   /'
        fi
      fi
    else
      echo -e "\n❌ ${base} missing from ${label} backup"
    fi
  done
}

# Main loop over REFSETS
for entry in "${REFSETS[@]}"; do
    IFS='|' read -r current ref_pro ref_perso <<<"${entry}"

    # Select primary/secondary based on environment
    if [[ "${current_env}" == "pro" ]]; then
        primary="${ref_pro}"
        secondary="${ref_perso}"
        secondary_label="perso"
    else
        primary="${ref_perso}"
        secondary="${ref_pro}"
        secondary_label="pro"
    fi

    # Readable section header for output
    printf "\n============================================\n"
    printf "%-15s %s\n"    "🔎  Auditing from:" "${current}"
    printf "%-15s %s\n"    "  Environment:"     "${current_env}"
    printf "%-15s %s\n"    "    ❯ from:"        "${primary}"
    printf "%-15s %s\n\n"  "  ➜ against:"       "${secondary}"

    # Audits
    audit_against "${current}" "${primary}"   "${current_env}"
    audit_against "${current}" "${secondary}" "${secondary_label}"
done