#!/usr/bin/env bash
# claude-reap — close Claude sessions that have gone quiet, and say so on their tty.
#
# neo is an 8 GB box. A finished session costs as much resident RAM as a working
# one, and the sessions that killed it twice were mostly *done* — last words
# "great", "yes", "compush now" — just sitting there. So: reap the quiet ones.
#
# Idleness is the mtime of the session's own transcript. Claude rewrites that
# file on every turn, so a session that is thinking, tool-calling, or streaming
# keeps touching it; only one waiting on a human goes stale. That makes mtime a
# truthful "nobody is here" signal, and means we never reap live work.
#
# Nothing is lost: the transcript IS the session. We print the `--resume` line
# onto the terminal we just cleared, so the way back is sitting where the
# session used to be.
#
# Usage:
#   claude-reap            # reap sessions idle >= IDLE_MINUTES (default 30)
#   claude-reap 45         # ...with an explicit threshold
#   claude-reap 30 dry     # report only, kill nothing

set -u

THRESHOLD="${1:-${IDLE_MINUTES:-30}}"
DRY="${2:-}"
PROJECTS="$HOME/.claude/projects"
now=$(date +%s)

for pid in $(pgrep -x claude); do
    # The transcript this session holds open. Subagent transcripts live under
    # subagents/ and belong to a parent that is still very much alive.
    transcript=$(lsof -p "$pid" -Fn 2>/dev/null \
        | grep -m1 -o "${PROJECTS}/[^ ]*\.jsonl" \
        | grep -v '/subagents/')
    [ -z "$transcript" ] && continue

    mtime=$(stat -f %m "$transcript" 2>/dev/null) || continue
    idle=$(( (now - mtime) / 60 ))
    [ "$idle" -lt "$THRESHOLD" ] && continue

    id=$(basename "$transcript" .jsonl)
    tty=$(ps -o tty= -p "$pid" 2>/dev/null | tr -d ' ')

    if [ -n "$DRY" ]; then
        echo "would reap ${id%%-*} (idle ${idle}m, tty ${tty:-?})"
        continue
    fi

    kill "$pid" 2>/dev/null || continue

    # Leave the way back where the session was, not in a log nobody reads.
    if [ -n "$tty" ] && [ -w "/dev/$tty" ]; then
        {
            printf '\n\033[33m─── claude-reap ───\033[0m\n'
            printf '  quiet for %sm, so it was closed to keep neo off swap.\n' "$idle"
            printf '  the conversation is intact — pick it back up with:\n\n'
            printf '    \033[36mclaude --resume %s\033[0m\n\n' "$id"
        } > "/dev/$tty" 2>/dev/null
    fi

    echo "reaped ${id%%-*} (idle ${idle}m, tty ${tty:-?})"
done