Rewrite babble as modular Ruby application

[Copilot]

Replaces ksh implementation with clean Ruby architecture that orchestrates Homebrew, Mac App Store, and macOS system upgrades. Eliminates config duplication and fixes validation bugs from prototype.

Architecture

Entry flow: Bash wrapper (bin/babble) loads brew.env files, sources Homebrew's utils/ruby.sh for portable Ruby, execs orchestrator.

Module structure:

lib/babble/
├── orchestrator.rb      # Sequential flow: brew → mas → macos
├── config_manager.rb    # Shared validation (eliminates BrewUpgrade/MasUpgrade duplication)
├── brew_upgrade.rb      # Detect outdated → quit apps → upgrade → reopen
├── mas_upgrade.rb       # Same workflow for Mac App Store
├── macos_update.rb      # softwareupdate wrapper
├── app_manager.rb       # Lifecycle: detect (lsappinfo) → quit (JXA) → reopen (BundleLauncher)
├── bundle_launcher.rb   # Multi-tier reopen: open -b → launchctl asuser → lsregister
├── quarantine_purger.rb # Remove com.apple.quarantine xattrs from cask bundles
└── waiter.rb           # Interactive prompts with custom continuation messages

Swift GUI: Auto-compiled on first use, cached to ~/.cache/babble/quit_alert. Supports dark/light mode via embedded base64 SVG icons.

Config Example

apps:
  homebrew:
    - token: iterm2
      bundle_ids: [com.googlecode.iterm2]
      unsafe_to_quit: true  # Shows native alert before quit
  mas:
    - app_id: 1595464182
      name: MonitorControlLite
      bundle_ids: [app.monitorcontrol.MonitorControlLite]
      unsafe_to_quit: true

Fixes

• quit_message validation: Fixed variable scope bug where existing_value/new_value referenced wrong block
• ReDoS vulnerability: Replaced /[a-z0-9_.-]+(?:\.[a-z0-9_.-]+)+/i (nested quantifiers) with non-backtracking pattern
• Message flow: Added continuation_message parameter to eliminate duplicate "Continuing..." output
• yq integration: Soft dependency for config reorganization (skips gracefully if missing)

Standards

All Ruby modules use typed: strict and frozen_string_literal: true. Zero commented-out code. Shared constants extracted (CACHE_DIR).

Original prompt

Overview

Rewrite babble as a clean, modular Ruby application that orchestrates upgrades for Homebrew (formulae + casks), Mac App Store apps, and macOS system updates. This replaces the current ksh implementation on main with a new Ruby-based architecture.

The existing prototype on the refactor/modular branch should be used as reference for understanding intent, but the implementation should be clean — no commented-out code, no debug prints, no duplicated modules.

Key Design Decisions

Architecture

• Bash entry point (bin/babble): Loads brew.env files, sources Homebrew's utils/ruby.sh to find HOMEBREW_RUBY_PATH, then execs the Ruby orchestrator. This pattern is essential and must be preserved faithfully from the prototype's refactor/bin/babble_claude_main.
• Ruby orchestrator: Modular library under lib/babble/ with clear separation of concerns.
• Swift GUI: Native macOS NSAlert for "unsafe to quit" apps. Auto-compiled on first use via xcrun swiftc and cached locally. No pre-built binaries shipped — macOS will refuse to run unsigned/unnotarized distributed binaries.

Module Structure

File	Responsibility
lib/babble/config_manager.rb	Load, validate, and merge the unified YAML config. Shared by brew and MAS — eliminates the massive duplication between the prototype's BrewUpgrade and MasUpgrade modules.
lib/babble/brew_upgrade.rb	Outdated detection (brew outdated --json=v2), quit-before-upgrade, brew upgrade, reopen-after-upgrade. Delegates config to ConfigManager, app lifecycle to AppManager.
lib/babble/mas_upgrade.rb	mas outdated, quit-before-upgrade, mas upgrade, reopen. Same delegation pattern.
lib/babble/macos_update.rb	softwareupdate wrapper.
lib/babble/app_manager.rb	Detect running apps (via lsappinfo), quit (via JXA/osascript), invoke Swift GUI for unsafe_to_quit apps, reopen (via BundleLauncher).
lib/babble/bundle_launcher.rb	Multi-tier app reopen logic: NSWorkspace.openApplication → launchctl asuser fallback → lsregister re-registration. Based on prototype's MacUtils::BundleLauncher.
lib/babble/quarantine_purger.rb	Remove Gatekeeper quarantine/provenance xattrs from cask app bundles. Based on prototype's QuarantinePurger.
lib/babble/waiter.rb	Interactive terminal prompts with space-bar-to-continue.
lib/babble/orchestrator.rb	Top-level flow: brew_upgrade → mas_upgrade → macos_update in sequence.

Entry Points

File	Role
bin/babble	Bash wrapper: initialize Homebrew env, load brew.env, source utils/ruby.sh, exec Ruby orchestrator
lib/babble/cli.rb	Ruby CLI entry point invoked by the bash wrapper

Configuration

The unified YAML config file (config/apps.yml) defines apps with their bundle IDs, unsafe_to_quit flags, and quit_messages. Structure from prototype:

apps:
  homebrew:
    - token: iterm2
      bundle_ids:
        - com.googlecode.iterm2
      unsafe_to_quit: true
    - token: adobe-acrobat-reader
      bundle_ids:
        - com.adobe.AdobeRdrCEFHelper
        - com.adobe.Reader
        - com.adobe.Reader.helper
      unsafe_to_quit: false
  mas:
    - app_id: 1595464182
      name: MonitorControlLite
      bundle_ids:
        - app.monitorcontrol.MonitorControlLite
      unsafe_to_quit: true

Swift Quit Alert GUI

• Source: swift/src/quit_alert.swift — NSAlert with dark/light mode SVG icons (base64 encoded), localized Cancel/Continue buttons
• Auto-compiled via xcrun swiftc on first use, cached to ~/.cache/babble/quit_alert (or $XDG_CACHE_HOME/babble/)
• Compiled for both x86_64 and arm64 targeting macOS 13+
• The alert message pattern: "{AppName} cannot be open during installation. Click Continue to quit {AppName} and begin the update. The application will open when the update is complete."
• Exit codes: 0 = Continue (user approved quit), 1 = Cancel, 2 = icon load failure, 3 = usage error

Waiter Improvements

The Waiter.waiter method must accept a custom continuation message parameter:

def self.waiter(key, continuation_message: "Continuing...")

This eliminates duplicate/misleading messages. Callers pass context-appropriate strings:

• Waiter.waiter("run_command", continuation_message: "Upgrading outdated packages...")
• Waiter.waiter("run_command", continuation_message: "Checking for outdated packages...")
• Waiter.waiter("next_section", continuation_message: "Proceeding to Mac App Store upgrades...")

Message Flow Fix

The prototype shows duplicate messages. The correct flow:

Stage	Message
Before waiter	Preparing to upgrade all outdated packages...
Waiter prompt	→ Run command: Press Space bar to continue, or Ctrl-C to exit.
After space bar	Custom continuation message from caller (NOT generic "Continuing...")
Actual upgrade	(brew upgrade output...

This pull request was created from Copilot chat.

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