Add commenter targeting mode

src/services/monitor.ts

@@ -3,7 +3,9 @@ import {
   RedditSubredditUnavailableError,
   type RedditApiClient,
   type RedditPost,
+  type BrowsingThing,
 } from '../reddit/api.js';
+import type { CommentReactionCandidate, CommentReactionVerdict } from '../ai/openrouter.js';
 import type { PostsRepository } from '../database/repositories.js';
 import type { Config } from '../config/index.js';
 import type { Logger } from '../utils/logger.js';
@@ -33,11 +35,20 @@ export interface SubredditPollingControl {
   isSubredditEnabled(subreddit: string): boolean;
 }
 
+export interface CommentReactionScreener {
+  screenCommentReactions(comments: readonly CommentReactionCandidate[]): Promise<CommentReactionVerdict[]>;
+}
+
+const COMMENT_REACTION_CONFIDENCE = 0.8;
+const COMMENT_POST_SCAN_LIMIT = 5;
+const COMMENTS_PER_POST_LIMIT = 20;
+
 export class MonitorService {
   // Flips on each call so that when both pools have candidates the bot
   // alternates between image and chat instead of always favouring whichever
   // type the random shuffle put first.
   private chatGoesFirst = false;
+  private readonly commentReactionCache = new Map<string, CommentReactionVerdict>();
 
   constructor(
     private redditApi: RedditApiClient,
@@ -47,6 +58,7 @@ export class MonitorService {
     private logger: Logger,
     private delayBetweenFetchesMs: number = 1000,
     private readonly pollingControl?: SubredditPollingControl,
+    private readonly commentReactionScreener?: CommentReactionScreener,
   ) { }
 
   async getUnprocessedPosts(): Promise<RedditPost[]> {
@@ -65,7 +77,10 @@ export class MonitorService {
     for (const subreddit of subreddits) {
       try {
         this.logger.debug(`Checking r/${subreddit.name} (${subreddit.type}) for new posts...`);
-        const posts = await this.redditApi.getNewPosts(subreddit.name, 25, subreddit.type);
+        const listedPosts = await this.redditApi.getNewPosts(subreddit.name, 25, subreddit.type);
+        const posts = subreddit.targetingMode === 'comment-author'
+          ? await this.findCommentCandidates(listedPosts)
+          : listedPosts;
         const summary: ListingScreeningSummary = {
           scanned: 0,
           alreadyProcessed: 0,
@@ -211,7 +226,9 @@ export class MonitorService {
     if (!this.isSubredditEnabled(subreddit.name)) return [];
     try {
       this.logger.debug(`Collecting candidate posts from r/${subreddit.name} (${subreddit.type})...`);
-      return await this.redditApi.getNewPosts(subreddit.name, 25, subreddit.type);
+      const posts = await this.redditApi.getNewPosts(subreddit.name, 25, subreddit.type);
+      if (subreddit.targetingMode !== 'comment-author') return posts;
+      return await this.findCommentCandidates(posts);
     } catch (error) {
       if (error instanceof RedditRateLimitError) throw error;
       if (error instanceof RedditSubredditUnavailableError) {
@@ -225,6 +242,71 @@ export class MonitorService {
     }
   }
 
+  private async findCommentCandidates(posts: readonly RedditPost[]): Promise<RedditPost[]> {
+    if (!this.commentReactionScreener) {
+      this.logger.warn('Comment-author targeting is configured but no reaction screener is available');
+      return [];
+    }
+    const pairs: Array<{ post: RedditPost; comment: BrowsingThing }> = [];
+    for (const post of posts.slice(0, COMMENT_POST_SCAN_LIMIT)) {
+      const comments = await this.redditApi.getBrowsingComments(
+        post.subreddit,
+        post.id.replace(/^t3_/, ''),
+        COMMENTS_PER_POST_LIMIT,
+      );
+      for (const comment of comments) {
+        if (comment.removed || comment.author === '[deleted]' || comment.author === 'AutoModerator') continue;
+        if (comment.author.toLowerCase() === post.author.toLowerCase()) continue;
+        if (comment.text.trim().length < 8) continue;
+        pairs.push({ post, comment });
+      }
+    }
+    if (pairs.length === 0) return [];
+
+    const unseen = pairs.filter(({ comment }) => !this.commentReactionCache.has(comment.fullname));
+    if (unseen.length > 0) {
+      const verdicts = await this.commentReactionScreener.screenCommentReactions(
+        unseen.map(({ comment }) => ({ id: comment.fullname, text: comment.text })),
+      );
+      const returned = new Map(verdicts.map((verdict) => [verdict.id, verdict]));
+      for (const { comment } of unseen) {
+        this.commentReactionCache.set(comment.fullname, returned.get(comment.fullname) ?? {
+          id: comment.fullname,
+          qualifies: false,
+          expressedGender: 'unknown',
+          confidence: 0,
+          evidence: 'Classifier returned no verdict',
+        });
+      }
+      while (this.commentReactionCache.size > 2_000) {
+        const oldest = this.commentReactionCache.keys().next().value;
+        if (typeof oldest !== 'string') break;
+        this.commentReactionCache.delete(oldest);
+      }
+    }
+    return pairs.flatMap(({ post, comment }): RedditPost[] => {
+      const verdict = this.commentReactionCache.get(comment.fullname);
+      if (!verdict?.qualifies || verdict.confidence < COMMENT_REACTION_CONFIDENCE) return [];
+      return [{
+        ...post,
+        id: comment.fullname,
+        name: comment.fullname,
+        author: comment.author,
+        author_fullname: undefined,
+        permalink: comment.permalink,
+        created_utc: comment.createdAt / 1_000,
+        targetComment: {
+          body: comment.text,
+          permalink: comment.permalink,
+          sourcePostId: post.id,
+          sourcePostAuthor: post.author,
+          expressedGender: verdict.expressedGender,
+          confidence: verdict.confidence,
+        },
+      }];
+    });
+  }
+
   /** Apply cheap eligibility checks before any profile or AI work. */
   async screenCandidate(post: RedditPost, sourceType: 'image' | 'chat'): Promise<CandidateScreeningResult> {
     if (this.recipientHistory.hasSentTo(post.author)) {

src/services/processor.ts

@@ -198,7 +198,7 @@ export class ProcessorService {
           .replace('{author}', post.author)
           .replace('{flair}', post.link_flair_text || '(none)')
       : selectedStrategy?.promptOverride;
-    const message = await this.aiClient.generateMessage(
+    const messageArgs = [
       analysis.description,
       post.title,
       post.author,
@@ -208,7 +208,13 @@ export class ProcessorService {
       post.link_flair_text ?? undefined,
       tone.scripted ? undefined : tone.profile.promptGuidance || undefined,
       this.recentMessageProvider('image'),
-    );
+    ] as const;
+    const message = post.targetComment
+      ? await this.aiClient.generateMessage(
+          ...messageArgs,
+          `<<<UNTRUSTED PUBLIC COMMENT>>>\n${post.targetComment.body.slice(0, 500)}\n<<<END COMMENT>>>`,
+        )
+      : await this.aiClient.generateMessage(...messageArgs);
 
     if (!message || message.length < 10) {
       this.logger.warn(

src/services/reddit-account-runtime-builder.ts

@@ -206,6 +206,7 @@ async function buildRuntime(
     const monitorService = new MonitorService(
       redditApi, postsRepo, recipientDeduplicator, accountConfig, logger,
       1000, createConfigBackedSubredditPollingControl(config, new ConfigStore(db), logger),
+      aiClient,
     );
     const processorService = new ProcessorService(
       redditApi,