#!/bin/bash
# 当前链路严重退化（18 次断开 / 20 次 quic 错误 / 公网 0/10）。
# 试试 ha-connections=1：少一条并发 QUIC 就少一份争抢。
set -u

RELAY_DIR=/root/lanremote-relay
UNIT=/etc/systemd/system/lanremote-tunnel.service
URL=https://relay.xxmxxs.top

echo "===== 1. 改成 ha=1 ====="
cat > "$UNIT" <<'EOF'
[Unit]
Description=LanRemote Cloudflare 具名隧道
After=network-online.target lanremote-relay.service
Wants=network-online.target lanremote-relay.service

[Service]
Type=simple
# 协议：必须 QUIC（这条线路挡了 HTTP/2 的 TCP 7844）
# 连接数：1
#   实测 4 条并发 QUIC 握手互相挤（只成功 1 条）；
#   链路退化时 2 条也会有一条一直失败重试、拖累另一条。
#   1 条最稳。丢冗余换稳定 —— 看门狗会在断的时候重启。
ExecStart=/usr/local/bin/cloudflared tunnel --no-autoupdate --edge-ip-version 4 --ha-connections 1 --retries 5 --config /root/.cloudflared/config.yml run lanremote
Restart=always
RestartSec=5
MemoryMax=128M
StandardOutput=append:/root/lanremote-relay/tunnel.log
StandardError=append:/root/lanremote-relay/tunnel.log

[Install]
WantedBy=multi-user.target
EOF

systemctl stop lanremote-tunnel 2>/dev/null || true
pkill -f cloudflared 2>/dev/null || true
sleep 3
rm -f "$RELAY_DIR/tunnel.log"
systemctl daemon-reload
systemctl start lanremote-tunnel
echo "  已启动，等 40 秒建连接…"
sleep 40

echo
echo "===== 2. 连接情况 ====="
echo -n "  ha_connections = "
curl -s --max-time 5 http://127.0.0.1:20241/metrics 2>/dev/null \
    | grep '^cloudflared_tunnel_ha_connections' | awk '{print $2}'
echo "  注册: $(grep -c 'Registered tunnel connection' $RELAY_DIR/tunnel.log 2>/dev/null || echo 0)"
echo "  断开: $(grep -c 'Connection terminated' $RELAY_DIR/tunnel.log 2>/dev/null || echo 0)"

echo
echo "===== 3. 公网连打 15 次 ====="
OK=0
for i in $(seq 1 15); do
    C=$(timeout 20 curl -4 -s -o /dev/null -w '%{http_code}' \
        -H 'User-Agent: LanRemote/1.4.0' "$URL/v1/health" 2>/dev/null)
    [ "$C" = "200" ] && { OK=$((OK+1)); M="✓"; } || M="✗"
    printf "    %2d: %s %s\n" "$i" "$M" "${C:-超时}"
    sleep 2
done
PCT=$((OK * 100 / 15))
echo "  公网 $OK / 15  ($PCT%)"

echo
echo "===== 4. 再等 60 秒看长稳不稳 ====="
sleep 60
OK2=0
for i in $(seq 1 10); do
    C=$(timeout 20 curl -4 -s -o /dev/null -w '%{http_code}' \
        -H 'User-Agent: LanRemote/1.4.0' "$URL/v1/health" 2>/dev/null)
    [ "$C" = "200" ] && OK2=$((OK2+1))
    sleep 3
done
echo "  第二轮 $OK2 / 10"
echo -n "  ha_connections = "
curl -s --max-time 5 http://127.0.0.1:20241/metrics 2>/dev/null \
    | grep '^cloudflared_tunnel_ha_connections' | awk '{print $2}'

echo
echo "===== 5. 结论 ====="
echo "  ha=1: 第一轮 $OK/15，第二轮 $OK2/10"
if [ "$OK" -ge 12 ] || [ "$OK2" -ge 8 ]; then
    echo "  ✓ 比 ha=2 好，定 ha=1"
else
    echo "  ✗ 还是不行 —— 这是链路本身的问题（运营商/信号），"
    echo "     不是配置能救的。看门狗会持续重启。"
fi