#!/bin/bash
# 试不同的 cloudflared 连接数，找出这条线路上最稳的配置。
#
# 现状：4 条 ha-connection 的 QUIC 全在超时
#   "failed to dial to edge with quic: timeout: handshake did not complete"
# 怀疑：这条 4G 线路对 UDP 有节制 —— 同时建 4 条 QUIC 连接反而更容易被限。
#
# 试：ha=4 / ha=2 / ha=1，各观察一轮。
set -u

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

restart_with() {
    local ha="$1"
    echo "===== 试 ha-connections=$ha ====="
    systemctl stop lanremote-tunnel 2>/dev/null || true
    pkill -f cloudflared 2>/dev/null || true
    sleep 3

    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
# 必须 QUIC：实测这条线路把 HTTP/2 用的 TCP 7844 挡了
ExecStart=/usr/local/bin/cloudflared tunnel --no-autoupdate --edge-ip-version 4 --ha-connections $ha --retries 5 --config /root/.cloudflared/config.yml run lanremote
Restart=always
RestartSec=5
MemoryMax=128M
StandardOutput=append:$RELAY_DIR/tunnel.log
StandardError=append:$RELAY_DIR/tunnel.log

[Install]
WantedBy=multi-user.target
EOF
    systemctl daemon-reload
    rm -f "$RELAY_DIR/tunnel.log"
    systemctl start lanremote-tunnel
    echo "  等 50 秒让它建连接…"
    sleep 50

    local conns
    conns=$(grep -c 'Registered tunnel connection' "$RELAY_DIR/tunnel.log" 2>/dev/null || echo 0)
    local drops
    drops=$(grep -c 'Connection terminated' "$RELAY_DIR/tunnel.log" 2>/dev/null || echo 0)
    echo "  已注册 $conns 条，断开 $drops 次"

    local ok=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" ] && ok=$((ok + 1))
        printf "    %2d: HTTP %s\n" "$i" "${C:-超时}"
        sleep 2
    done
    echo "  >>> ha=$ha 可用率 $ok/10"
    echo "$ha $ok $conns $drops" >> /root/ha_result.txt
    echo
}

: > /root/ha_result.txt
restart_with 4
restart_with 2
restart_with 1

echo "===== 汇总 ====="
printf "  %-8s %-10s %-10s %s\n" "ha" "可用/10" "已注册" "断开"
while read -r ha ok conns drops; do
    printf "  %-8s %-10s %-10s %s\n" "$ha" "$ok/10" "$conns" "$drops"
done < /root/ha_result.txt

BEST=$(sort -k2 -nr /root/ha_result.txt | head -1 | awk '{print $1}')
BEST_OK=$(sort -k2 -nr /root/ha_result.txt | head -1 | awk '{print $2}')
echo
echo "  最稳的是 ha-connections=$BEST（$BEST_OK/10）"
echo "$BEST" > /root/best_ha.txt