# Google Chat Proactive Messaging - Implementation Summary

This document summarizes the changes made to enable proactive messaging in the Google Chat extension.

## Files Modified

### 1. `src/config/types.googlechat.ts`
**Added:**
- `GoogleChatKnownSpace` type - Structure for cached space entries
- `GoogleChatKnownSpaces` type - Map of user IDs to space info
- `knownSpaces` field to `GoogleChatAccountConfig` - Stores cached space mappings

### 2. `src/config/zod-schema.providers-core.ts`
**Added:**
- `GoogleChatKnownSpaceSchema` - Zod validation schema for space cache entries
- `knownSpaces` field to `GoogleChatAccountSchema` - Config validation

### 3. `extensions/googlechat/src/space-cache.ts` (NEW)
**Created:**
- `getKnownSpaces()` - Retrieve cached spaces for an account
- `getCachedSpaceForUser()` - Look up space by user ID
- `hasCachedSpace()` - Check if space is cached
- `buildSpaceCachePatch()` - Create config patch for new cache entries
- `extractSpaceInfoFromEvent()` - Extract space info from incoming messages

### 4. `extensions/googlechat/src/targets.ts`
**Modified:**
- Updated `resolveGoogleChatOutboundSpace()` to accept config and options
- Added cache lookup before calling `findDirectMessage` API
- Added `ResolveSpaceOptions` type for `useCache` and `useFindDirectMessage` flags
- Improved error messages with actionable guidance

### 5. `extensions/googlechat/src/monitor.ts`
**Modified:**
- Added import for `space-cache` utilities
- Added space caching logic in `processMessageWithPipeline()`
- Spaces are now cached automatically when users message the bot

### 6. `extensions/googlechat/src/channel.ts`
**Modified:**
- Updated `sendText` to pass config to `resolveGoogleChatOutboundSpace()`
- Updated `sendMedia` to pass config to `resolveGoogleChatOutboundSpace()`
- Updated `notifyApproval` to pass config to `resolveGoogleChatOutboundSpace()`

### 7. `extensions/googlechat/PROACTIVE-MESSAGING.md` (NEW)
**Created:**
- Comprehensive documentation for proactive messaging
- Usage examples for all 4 methods
- Troubleshooting guide
- Best practices

## How It Works

1. **Incoming Message** → `monitor.ts` extracts space info and caches it
2. **Outgoing Message** → `channel.ts` calls `resolveGoogleChatOutboundSpace()`
3. **Resolution** → `targets.ts` checks cache first, then API fallback
4. **Delivery** → Message sent via `api.ts`

## Usage Examples

### CLI
```bash
# Using user ID (auto-resolves to cached space)
moltbot message send --channel googlechat --to "users/123" --text "Hello!"

# Using space ID (direct)
moltbot message send --channel googlechat --to "spaces/AAA" --text "Hello!"
```

### Config (Cron)
```json
{
  "cron": {
    "jobs": [{
      "schedule": "0 9 * * *",
      "text": "Morning!",
      "target": "users/123",
      "channel": "googlechat"
    }]
  }
}
```

### Config Structure
```json
{
  "channels": {
    "googlechat": {
      "knownSpaces": {
        "users/123456": {
          "spaceId": "spaces/AAAAxxxx",
          "displayName": "John Doe",
          "type": "DM",
          "lastSeenAt": 1706515200000
        }
      }
    }
  }
}
```

## Benefits

1. **Automatic Caching** - No manual space ID management needed
2. **Multiple Fallbacks** - Cache → API → Error with guidance
3. **Backward Compatible** - Existing space ID targeting still works
4. **Well Documented** - Clear patterns for developers

## Testing Recommendations

1. Test incoming messages cache the space
2. Test proactive send using cached user ID
3. Test proactive send using space ID directly
4. Test error case when user hasn't messaged first
5. Test with multiple accounts