#!/usr/bin/env bash
# Add hosts file entries and optionally configure Cloudflare DNS for local resolution.
# Fixes DNS_PROBE_FINISHED_NXDOMAIN when local/ISP DNS fails to resolve d-bis.org and defi-oracle.io domains.
# Run: sudo ./scripts/fix-local-dns-hosts.sh

set -euo pipefail

PUBLIC_IP="76.53.10.36"
HOSTS_FILE="/etc/hosts"
START_MARKER="# --- d-bis-defi-oracle-hosts-start ---"
END_MARKER="# --- d-bis-defi-oracle-hosts-end ---"

# Domains that resolve to NPMplus (76.53.10.36)
DOMAINS=(
  "explorer.d-bis.org"
  "explorer.defi-oracle.io"
  "rpc-http-pub.d-bis.org"
  "rpc-ws-pub.d-bis.org"
  "rpc.d-bis.org"
  "rpc2.d-bis.org"
  "ws.rpc.d-bis.org"
  "ws.rpc2.d-bis.org"
  "rpc-http-prv.d-bis.org"
  "rpc-ws-prv.d-bis.org"
  "dbis-admin.d-bis.org"
  "dbis-api.d-bis.org"
  "dbis-api-2.d-bis.org"
  "secure.d-bis.org"
  "mim4u.org"
  "www.mim4u.org"
  "secure.mim4u.org"
  "training.mim4u.org"
  "rpc.public-0138.defi-oracle.io"
  "rpc.defi-oracle.io"
  "wss.defi-oracle.io"
)

# Check root
if [ "$(id -u)" -ne 0 ]; then
  echo "This script needs root for /etc/hosts and /etc/resolv.conf."
  echo "Run: sudo $0"
  echo ""
  echo "Or manually add to /etc/hosts (sudo nano /etc/hosts):"
  echo ""
  for domain in "${DOMAINS[@]}"; do
    echo "$PUBLIC_IP $domain"
  done
  exit 1
fi

echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
echo "  Fix local DNS — hosts file + Cloudflare DNS"
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
echo ""

# 1. Remove old block if present
if grep -q "$START_MARKER" "$HOSTS_FILE" 2>/dev/null; then
  echo "Removing existing d-bis/defi-oracle block..."
  sed -i "/$START_MARKER/,/$END_MARKER/d" "$HOSTS_FILE"
fi

# 2. Add hosts entries
echo "Adding hosts entries for $PUBLIC_IP..."
echo "" >> "$HOSTS_FILE"
echo "$START_MARKER" >> "$HOSTS_FILE"
for domain in "${DOMAINS[@]}"; do
  echo "$PUBLIC_IP $domain" >> "$HOSTS_FILE"
done
echo "$END_MARKER" >> "$HOSTS_FILE"
echo "" >> "$HOSTS_FILE"
echo "Added ${#DOMAINS[@]} entries."
echo ""

# 3. WSL: Configure Cloudflare DNS in resolv.conf (persists until WSL restart)
if [ -f /etc/wsl.conf ] 2>/dev/null || grep -q microsoft /proc/version 2>/dev/null; then
  echo "WSL detected. Configuring Cloudflare DNS..."
  if ! grep -q "generateResolvConf" /etc/wsl.conf 2>/dev/null; then
    { echo ""; echo "[network]"; echo "generateResolvConf = false"; } >> /etc/wsl.conf
    echo "Added generateResolvConf = false to /etc/wsl.conf"
  fi
  cat > /etc/resolv.conf << 'EOF'
nameserver 1.1.1.1
nameserver 1.0.0.1
EOF
  echo "Set /etc/resolv.conf to Cloudflare DNS (1.1.1.1, 1.0.0.1)"
else
  echo "For Cloudflare DNS on Linux: add nameserver 1.1.1.1 to /etc/resolv.conf or use NetworkManager."
fi

echo ""
echo "Done. Test with: curl -sI https://explorer.d-bis.org/ | head -3"
echo ""