#!/bin/bash

# Script to fix backend server port conflict (8443 is used by code-server)
# Backend should use port 8081

set -e

SERVER_IP="147.45.152.129"
SERVER_USER="root"

echo "🔧 Fixing backend server port conflict..."
echo "Backend will be moved from port 8443 to port 8081"
echo ""

ssh "$SERVER_USER@$SERVER_IP" << 'ENDSSH'
    set -e
    
    echo "📊 Step 1: Checking current port usage..."
    echo "Port 8443:"
    ss -tuln | grep 8443 || echo "  Not in use"
    
    echo ""
    echo "Port 8081:"
    ss -tuln | grep 8081 || echo "  Not in use"
    
    echo ""
    echo "🔧 Step 2: Updating backend systemd service to use port 8081..."
    
    # Backup current service file
    cp /etc/systemd/system/mnemo_cards_server.service /etc/systemd/system/mnemo_cards_server.service.backup.$(date +%Y%m%d_%H%M%S)
    
    # Update port from 8443 to 8081
    sed -i 's/-p 8443/-p 8081/g' /etc/systemd/system/mnemo_cards_server.service
    
    echo "Updated service file:"
    cat /etc/systemd/system/mnemo_cards_server.service
    
    echo ""
    echo "🔧 Step 3: Checking nginx API configuration..."
    
    if [ -f /etc/nginx/sites-available/api ]; then
        echo "Current API nginx config proxy_pass:"
        grep "proxy_pass" /etc/nginx/sites-available/api | head -3
        
        echo ""
        echo "Updating nginx to proxy to port 8081..."
        
        # Backup nginx config
        cp /etc/nginx/sites-available/api /etc/nginx/sites-available/api.backup.$(date +%Y%m%d_%H%M%S)
        
        # Update proxy_pass to use port 8081 and 127.0.0.1 (IPv4) instead of localhost (IPv6)
        sed -i 's|proxy_pass https://localhost:8443|proxy_pass http://127.0.0.1:8081|g' /etc/nginx/sites-available/api
        sed -i 's|proxy_pass http://localhost:8443|proxy_pass http://127.0.0.1:8081|g' /etc/nginx/sites-available/api
        sed -i 's|proxy_pass http://localhost:8081|proxy_pass http://127.0.0.1:8081|g' /etc/nginx/sites-available/api
        
        echo "Updated proxy_pass:"
        grep "proxy_pass" /etc/nginx/sites-available/api | head -3
    else
        echo "⚠️  API nginx config not found"
    fi
    
    echo ""
    echo "📊 Step 4: Testing nginx configuration..."
    if /usr/sbin/nginx -t 2>&1; then
        echo "✅ nginx config is valid"
    else
        echo "❌ nginx config is invalid, restoring backup..."
        cp /etc/nginx/sites-available/api.backup.$(date +%Y%m%d_%H%M%S | sort -r | head -1) /etc/nginx/sites-available/api
        exit 1
    fi
    
    echo ""
    echo "🔄 Step 5: Reloading systemd and nginx..."
    systemctl daemon-reload
    systemctl reload nginx
    echo "✅ Reloaded"
    
    echo ""
    echo "🚀 Step 6: Starting backend server..."
    systemctl restart mnemo_cards_server
    
    echo ""
    echo "⏳ Waiting for server to start..."
    sleep 5
    
    echo ""
    echo "📊 Step 7: Checking backend server status..."
    systemctl status mnemo_cards_server --no-pager || true
    
    echo ""
    echo "📊 Step 8: Checking if port 8081 is now listening..."
    if ss -tuln | grep 8081; then
        echo "✅ Backend is listening on port 8081"
    else
        echo "⚠️  Backend is not listening on port 8081 yet"
        echo "Checking logs:"
        journalctl -u mnemo_cards_server -n 20 --no-pager
    fi
    
ENDSSH

echo ""
echo "✅ Done!"
echo ""
echo "📝 Summary:"
echo "   - code-server: 127.0.0.1:8443 (VSCode)"
echo "   - backend: 0.0.0.0:8081 (API)"
echo ""
echo "🌐 URLs:"
echo "   - API: https://api.mnemo-cards.online:8081/"
echo "   - VSCode: https://vscode.mnemo-cards.online/"