#!/usr/bin/env bash
# retention-rotate-chat-history.sh — retention piece 1 (board bug b67084660385).
# Rotates logs/chat-history.jsonl when it exceeds 10MB or is older than 7 days.
#
# Live-writer safety: the harvester (bin/response-harvester.py) opens the file
# in append mode per write and closes it immediately, so an atomic `mv` of the
# live file is safe — the next write recreates a fresh file. We also `touch`
# the new live file for tidiness and to keep ownership/visibility stable.
#
# Archives land in logs/archive/chat-history-YYYYMMDD-HHMMSS.jsonl.gz with a
# sha256 sidecar. Nothing is ever deleted by this script.
set -euo pipefail

ROOT="${NETVM_ROOT:-/home/super/Projects/NetVM}"
LIVE="$ROOT/logs/chat-history.jsonl"
ARCHIVE_DIR="$ROOT/logs/archive"
SIZE_LIMIT=$((10 * 1024 * 1024))   # 10MB
AGE_LIMIT_DAYS=7
TS="$(date -u +%Y%m%d-%H%M%S)"

mkdir -p "$ARCHIVE_DIR"

if [ ! -f "$LIVE" ]; then
  echo "SKIP chat-history: no live file at $LIVE"
  exit 0
fi

size="$(stat -c %s "$LIVE")"
age_days=$(( ( $(date +%s) - $(stat -c %Y "$LIVE") ) / 86400 ))

if [ "$size" -lt "$SIZE_LIMIT" ] && [ "$age_days" -lt "$AGE_LIMIT_DAYS" ]; then
  echo "SKIP chat-history: ${size}B, ${age_days}d old (limits ${SIZE_LIMIT}B / ${AGE_LIMIT_DAYS}d)"
  exit 0
fi

lines="$(wc -l < "$LIVE")"
base="chat-history-$TS"
echo "ROTATE chat-history: ${size}B / ${lines} lines (${age_days}d old) -> $ARCHIVE_DIR/$base.jsonl.gz"

mv "$LIVE" "$ARCHIVE_DIR/$base.jsonl"
gzip -9 "$ARCHIVE_DIR/$base.jsonl"
( cd "$ARCHIVE_DIR" && sha256sum "$base.jsonl.gz" > "$base.jsonl.gz.sha256" )
touch "$LIVE"

echo "OK chat-history: archived $base.jsonl.gz, live file recreated empty"