HIGH: Massive code duplication across AI modules (32K+ LOC)

[sfloess]

Severity

High

Description

All 8 non-Claude AI modules contain 90%+ duplicated code from the Claude module. This represents approximately 32,000 lines of duplicated code across:

• API client implementations
• UI components (chat windows, panels)
• Code completion providers
• Action handlers
• Settings panels
• Utility classes

Affected Modules

• ai/gemini/ - ~4,000 LOC duplicated from Claude
• ai/chatgpt/ - ~4,000 LOC duplicated from Claude
• ai/grok/ - ~4,000 LOC duplicated from Claude
• ai/mistral/ - ~4,000 LOC duplicated from Claude
• ai/perplexity/ - ~4,000 LOC duplicated from Claude
• ai/cohere/ - ~4,000 LOC duplicated from Claude
• ai/deepseek/ - ~4,000 LOC duplicated from Claude
• ai/openrouter/ - ~4,000 LOC duplicated from Claude

Impact

• DRY principle violation
• Bug fixes must be applied 9 times
• Inconsistent behavior across modules
• Maintenance nightmare
• Difficult to add new features

Recommended Solution

Create ai/common module with shared abstractions:

1. Abstract Base Classes:

   • AbstractAIClient - HTTP client, conversation history, error handling
   • AbstractChatTopComponent - Chat UI, message rendering
   • AbstractCompletionProvider - Code completion logic
   • AbstractConfigPanel - Settings UI

2. Shared Utilities:

   • AIClientFactory - Factory for creating clients
   • ConversationManager - Thread-safe conversation handling
   • RetryPolicy - Exponential backoff logic
   • StreamingResponseHandler - SSE/streaming handling

3. Module Structure:

ai/
├── common/                    # NEW
│   ├── api/
│   │   ├── AbstractAIClient.java
│   │   └── ConversationManager.java
│   ├── ui/
│   │   └── AbstractChatTopComponent.java
│   └── completion/
│       └── AbstractCompletionProvider.java
├── claude/
│   └── extends common classes
├── gemini/
│   └── extends common classes
└── ...

Estimated Impact

• Reduce codebase by ~25,000 LOC
• Single place for bug fixes
• Consistent behavior
• Easier to add AI provider 📊 Code Review Summary: 23-Module Suite Status #10

Priority

High - Technical debt affecting maintainability