#!/bin/bash
# Senti AI GCP Free Tier (e2-micro) Deployment Script
# Run this on your Ubuntu 22.04 LTS instance.

set -e

echo "=== SENTI AI GCP VM DEPLOYMENT CONFIGURATOR ==="

# 1. Check and Configure Swap Space (Crucial for 1GB RAM)
if [ ! -f /swapfile ]; then
    echo "[SYSTEM] Allocating 2GB swap space..."
    sudo fallocate -l 2G /swapfile
    sudo chmod 600 /swapfile
    sudo mkswap /swapfile
    sudo swapon /swapfile
    echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab
    echo "[SYSTEM] Swap space successfully enabled!"
else
    echo "[SYSTEM] Swap file already exists."
fi

# 2. Update System Package Repository
echo "[SYSTEM] Updating apt repositories..."
sudo apt-get update -y
sudo apt-get upgrade -y

# 3. Install System Dependencies
echo "[SYSTEM] Installing Redis, Nginx, Python3, and Git..."
sudo apt-get install -y git python3-pip python3-venv redis-server nginx curl

# 4. Install Node.js & PM2 (Process Manager)
if ! command -v pm2 &> /dev/null; then
    echo "[SYSTEM] Installing Node.js and PM2..."
    curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
    sudo apt-get install -y nodejs
    sudo npm install -p -g pm2
else
    echo "[SYSTEM] PM2 already installed."
fi

# 5. Configure Redis Server
echo "[SYSTEM] Configuring Redis..."
sudo systemctl enable redis-server
sudo systemctl start redis-server

# 6. Set Up Nginx Web Server Configurations
echo "[SYSTEM] Writing Nginx proxy configuration..."
sudo tee /etc/nginx/sites-available/senti << 'EOF'
server {
    listen 80;
    server_name localhost;

    location / {
        root /var/www/senti/frontend/dist;
        index index.html;
        try_files $uri $uri/ /index.html;
    }

    location /api {
        proxy_pass http://127.0.0.1:8000;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

    location /api/ws/ {
        proxy_pass http://127.0.0.1:8000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $host;
    }
}
EOF

# Enable Senti Nginx configuration
if [ -f /etc/nginx/sites-enabled/default ]; then
    sudo rm /etc/nginx/sites-enabled/default
fi
if [ ! -f /etc/nginx/sites-enabled/senti ]; then
    sudo ln -s /etc/nginx/sites-available/senti /etc/nginx/sites-enabled/senti
fi

echo "[SYSTEM] Restarting Nginx server..."
sudo systemctl restart nginx

# 7. Setup Application Workspace
echo "[SYSTEM] Preparing directories..."
sudo mkdir -p /var/www/senti
sudo chown -R $USER:$USER /var/www/senti

echo "=== GCP CONFIGURATION COMPLETED ==="
echo "Next Steps:"
echo "1. Clone the project or copy build files to: /var/www/senti"
echo "2. Navigate to your app directory, create a virtual environment, and install requirements:"
echo "   python3 -m venv .venv"
echo "   source .venv/bin/activate"
echo "   pip install -r requirements.txt maturin"
echo "3. Compile the Rust math library inside the virtual environment:"
echo "   cd senti_calc && maturin build --release && pip install --force-reinstall target/wheels/*.whl"
echo "4. Use PM2 to run the Python backend in the background:"
echo "   pm2 start ecosystem.config.js"