#!/usr/bin/env bash
# Phase 4 interop gate: download one torrent concurrently from two independent
# libtorrent seeds and require both peers to contribute blocks.
set -u
ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
SWARM="${1:-$ROOT/build/naut_swarm}"
SEEDER="$ROOT/tests/integration/seeder.py"
TOR="$ROOT/tests/fixtures/single_v1.torrent"
DATA="$ROOT/tests/fixtures/data"

python3 -c 'import libtorrent' 2>/dev/null || {
  echo "SKIP: python libtorrent not available"
  exit 77
}
[ -x "$SWARM" ] || { echo "FAIL: $SWARM not built"; exit 1; }

out="$(mktemp -d /tmp/naut_swarm.XXXXXX)"
log1="$(mktemp /tmp/naut_seed1.XXXXXX)"
log2="$(mktemp /tmp/naut_seed2.XXXXXX)"
slog="$(mktemp /tmp/naut_swarm_log.XXXXXX)"
seed1=""
seed2=""

cleanup() {
  [ -n "$seed1" ] && kill "$seed1" 2>/dev/null || true
  [ -n "$seed2" ] && kill "$seed2" 2>/dev/null || true
  rm -rf "$out" "$log1" "$log2" "$slog"
}
trap cleanup EXIT

python3 "$SEEDER" "$TOR" "$DATA" > "$log1" 2>&1 &
seed1=$!
python3 "$SEEDER" "$TOR" "$DATA" > "$log2" 2>&1 &
seed2=$!

port1=""
port2=""
for _ in $(seq 1 100); do
  port1="$(grep -oP 'PORT \K[0-9]+' "$log1" 2>/dev/null || true)"
  port2="$(grep -oP 'PORT \K[0-9]+' "$log2" 2>/dev/null || true)"
  [ -n "$port1" ] && [ "$port1" != 0 ] &&
    [ -n "$port2" ] && [ "$port2" != 0 ] && break
  sleep 0.1
done
if [ -z "$port1" ] || [ "$port1" = 0 ] ||
   [ -z "$port2" ] || [ "$port2" = 0 ]; then
  echo "FAIL: seeders did not start"
  cat "$log1" "$log2"
  exit 1
fi

if ! timeout 30 "$SWARM" "$TOR" "$out" \
     "127.0.0.1:$port1" "127.0.0.1:$port2" > "$slog" 2>&1; then
  echo "FAIL: swarm download did not complete"
  cat "$slog"
  exit 1
fi
if ! diff -r "$out/single.bin" "$DATA/single.bin" >/dev/null; then
  echo "FAIL: content mismatch"
  exit 1
fi
contributors="$(grep -Ec 'delivered [1-9][0-9]* blocks' "$slog" || true)"
if [ "$contributors" -lt 2 ]; then
  echo "FAIL: expected both peers to contribute"
  cat "$slog"
  exit 1
fi

echo "PASS: two-peer swarm produced byte-identical output"