#!/usr/bin/env bash
#
# Brave Browser configuration backup & diff tool (jq-enhanced)
#
# Usage:
#   brave_backup.sh backup [prefix]
#   brave_backup.sh diff <prefix>
#

set -euo pipefail

# --- CONFIG ---
BRAVE_DIR="$HOME/Library/Application Support/BraveSoftware/Brave-Browser"
FILES=(
  "Local State"
  "Default/Preferences"
  "Default/Secure Preferences"
)
BACKUP_DIR="/tmp/brave_backups"

# --- FUNCTIONS ---

jq_pretty() {
  local src="$1"
  local dest="$2"

  if jq -e . "$src" >/dev/null 2>&1; then
    jq --sort-keys . "$src" >"$dest"
    echo "    (jq formatted)"
    return 0
  else
    cp "$src" "$dest"
    echo "    (raw copy - not valid JSON)"
    return 1
  fi
}


backup_files() {
  local prefix="${1:-$(date +%Y%m%d_%H%M%S)}"
  local target_dir="${BACKUP_DIR}/${prefix}"
  mkdir -p "$target_dir"

  echo "🔒 Backing up Brave files to: $target_dir"
  for f in "${FILES[@]}"; do
    local src="${BRAVE_DIR}/${f}"
    local dest="${target_dir}/$(basename "$f")"
    if [[ -f "$src" ]]; then
      jq_pretty "$src" "$dest"
      echo "✅ Backed up (pretty JSON): $f → $dest"
    else
      echo "⚠️  Missing: $src"
    fi
  done

  echo "✅ Backup complete: $target_dir"
}


diff_files() {
  local prefix="${1:-}"
  if [[ -z "$prefix" ]]; then
    echo "❌ Please provide a prefix for diff comparison."
    exit 1
  fi
  local backup_dir="${BACKUP_DIR}/${prefix}"

  if [[ ! -d "$backup_dir" ]]; then
    echo "❌ Backup not found: $backup_dir"
    exit 1
  fi

  echo "🔍 Comparing current files with backup: $backup_dir"
  for f in "${FILES[@]}"; do
    local current="${BRAVE_DIR}/${f}"
    local backup="${backup_dir}/$(basename "$f")"
    if [[ -f "$current" && -f "$backup" ]]; then
      echo
      echo "=== DIFF for $(basename "$f") ==="

      local tmp_current=$(mktemp)
      # Try pretty-print; if fails, fall back to raw copy
      if ! jq_pretty "$current" "$tmp_current" >/dev/null; then
        cp "$current" "$tmp_current"
      fi

      diff -u "$backup" "$tmp_current" || true
      rm -f "$tmp_current"
    else
      echo "⚠️  Missing file in current or backup for: $(basename "$f")"
    fi
  done
}

# --- MAIN ---

case "${1:-}" in
  backup)
    backup_files "${2:-}"
    ;;
  diff)
    diff_files "${2:-}"
    ;;
  *)
    echo "Usage:"
    echo "  $0 backup [prefix]   # Backup Brave config files (prettified JSON)"
    echo "  $0 diff <prefix>     # Compare with a specific backup"
    exit 1
    ;;
esac