classifier.ts

import { createHash } from "node:crypto";

export type ClaudePaneStatus = "active" | "idle" | "permission" | "missing";

export interface PaneClassification {
  status: ClaudePaneStatus;
  dangerous: boolean;
  question: boolean;
  unresolvedFailure: boolean;
  claudeLike: boolean;
  fingerprint: string;
  excerpt: string;
}

const ANSI = /\x1b(?:\[[0-?]*[ -/]*[@-~]|\][^\x07]*(?:\x07|\x1b\\))/g;
const ACTIVE = /(?:esc to interrupt|(?:Creating|Thinking|Running|Working|Committing|Cogitating|Researching|Implementing|Testing|Building|Analyzing|Reading|Writing|Updating|Installing|Fixing|Reviewing|Planning|Searching|Compacting|Baking|Brewing|Crunching|Finagling|Hatching|Pondering|Ruminating|Whirring|Wandering|Channelling|Churning|Clauding)[…\.]{1,3})/i;
const PERMISSION = /(?:do you want to proceed|allow this command|allow (?:once|for this session|this tool)|yes,? and don['’]t ask|❯\s*1\.\s*yes|esc to cancel)/i;
const DANGEROUS = /(?:\brm\s+-[^\n]*r|\bsudo\b|\bgit\s+(?:push|reset\s+--hard|clean\s+-f)|\b(?:ssh|scp|rsync)\b|\b(?:deploy|production|staging)\b|\b(?:drop|truncate|delete)\s+(?:database|table|from)\b|\b(?:migrate|migration|artisan)\b|\.env\b|secret|credential|token|password)/i;
const QUESTION = /(?:\?\s*$|please (?:choose|confirm)|which (?:option|approach)|would you like|should i|need your (?:input|decision))/im;
const UNRESOLVED_FAILURE = /(?:\b(?:tests?|build|typecheck|lint|migration|deployment)\s+(?:has\s+)?failed\b|\bfailed\s+(?:tests?|build|typecheck|lint|migration|deployment)\b|\bcommand\s+(?:failed|exited)\s+(?:with\s+)?(?:code|status)\s*[1-9]\d*\b|\b(?:task|work|implementation)\s+(?:is\s+)?(?:blocked|incomplete|not\s+complete)\b|\b(?:unable|could not|cannot)\s+to\s+complete\b|\bunresolved\s+(?:failure|error|issue)\b)/im;
const CLAUDE_LIKE = /(?:claude code|accept edits on|esc to interrupt|thinking with (?:low|medium|high|xhigh|max) effort)/im;

export function cleanPane(raw: string): string {
  return raw
    .replace(ANSI, "")
    .replace(/\r/g, "")
    .split("\n")
    .map((line) => line.replace(/[ \t]+$/g, ""))
    .join("\n")
    .trim();
}

function meaningfulExcerpt(cleaned: string): string {
  const lines = cleaned.split("\n").filter((line) => {
    const text = line.trim();
    if (!text) return false;
    if (/^[─━═]+$/.test(text)) return false;
    if (/^(?:⏵⏵\s*)?accept edits on/i.test(text)) return false;
    if (/^(?:◈|✳|✻|·|\*)?\s*\d+\s+tokens?$/i.test(text)) return false;
    return true;
  });
  return lines.slice(-80).join("\n").slice(-12_000);
}

export function classifyPane(raw: string, exists = true): PaneClassification {
  if (!exists) {
    return {
      status: "missing",
      dangerous: false,
      question: false,
      unresolvedFailure: false,
      claudeLike: false,
      fingerprint: "missing",
      excerpt: "tmux session does not exist",
    };
  }

  const cleaned = cleanPane(raw);
  const excerpt = meaningfulExcerpt(cleaned);
  // capture-pane includes scrollback. Only the live tail should decide whether
  // Claude is currently active or waiting at a permission prompt.
  const liveLines = cleaned.split("\n");
  const stateWindow = liveLines.slice(-16).join("\n");
  const outcomeWindow = liveLines.slice(-24).join("\n");
  const permission = PERMISSION.test(stateWindow);
  const active = !permission && ACTIVE.test(stateWindow);
  const status: ClaudePaneStatus = permission ? "permission" : active ? "active" : "idle";
  const unresolvedFailure = status === "idle" && UNRESOLVED_FAILURE.test(outcomeWindow);
  const stableText = excerpt
    .replace(/\(\d+[smh](?:\s+\d+[smh])?[^)]*\)/g, "(elapsed)")
    .replace(/\b\d{1,3}(?:,\d{3})*\s+tokens?\b/gi, "tokens")
    .replace(/[✳✻✽·*]\s+/g, "");
  const fingerprint = createHash("sha256").update(`${status}\n${stableText}`).digest("hex").slice(0, 20);

  return {
    status,
    dangerous: permission && DANGEROUS.test(outcomeWindow),
    question: permission || QUESTION.test(excerpt),
    unresolvedFailure,
    claudeLike: CLAUDE_LIKE.test(cleaned),
    fingerprint,
    excerpt,
  };
}