#!/bin/bash
set -e

##############################################################################
# Brev Setup Script - Best Practices Example
##############################################################################
# This demonstrates all conventions used in the setup-scripts collection:
#   - Battle-tested user detection (works with ubuntu/shadeform/nvidia users)
#   - Idempotency (safe to re-run)
#   - Permission fixes (when running as root)
#   - Clear output with progress indicators
#   - Verification at the end
#   - Under 150 lines
#
# This example sets up a Python development environment with a simple web app
##############################################################################

# Detect Brev user (handles ubuntu, nvidia, shadeform, etc.)
detect_brev_user() {
    if [ -n "${SUDO_USER:-}" ] && [ "$SUDO_USER" != "root" ]; then
        echo "$SUDO_USER"
        return
    fi
    # Check for Brev-specific markers
    for user_home in /home/*; do
        username=$(basename "$user_home")
        [ "$username" = "launchpad" ] && continue
        if ls "$user_home"/.lifecycle-script-ls-*.log 2>/dev/null | grep -q . || \
           [ -f "$user_home/.verb-setup.log" ] || \
           { [ -L "$user_home/.cache" ] && [ "$(readlink "$user_home/.cache")" = "/ephemeral/cache" ]; }; then
            echo "$username"
            return
        fi
    done
    # Fallback to common users
    [ -d "/home/nvidia" ] && echo "nvidia" && return
    [ -d "/home/ubuntu" ] && echo "ubuntu" && return
    echo "ubuntu"
}

# Set USER and HOME if running as root
if [ "$(id -u)" -eq 0 ] || [ "${USER:-}" = "root" ]; then
    DETECTED_USER=$(detect_brev_user)
    export USER="$DETECTED_USER"
    export HOME="/home/$DETECTED_USER"
fi

echo " Example Setup Script - Python Web App"
echo "User: $USER | Home: $HOME"

##############################################################################
# Install System Dependencies
##############################################################################

echo "Installing system dependencies..."
sudo apt-get update -qq
sudo apt-get install -y -qq python3-pip python3-venv curl

##############################################################################
# Install Python Environment (Example: virtualenv)
##############################################################################

# Create project directory
PROJECT_DIR="$HOME/my-web-app"
mkdir -p "$PROJECT_DIR"

# Create virtual environment if it doesn't exist
if [ ! -d "$PROJECT_DIR/venv" ]; then
    echo "Creating Python virtual environment..."
    cd "$PROJECT_DIR"
    python3 -m venv venv
else
    echo "Virtual environment already exists, skipping..."
fi

# Activate and install dependencies
cd "$PROJECT_DIR"
source venv/bin/activate

echo "Installing Python packages..."
pip install --upgrade pip
pip install flask gunicorn requests

##############################################################################
# Create Example Application
##############################################################################

# Create a simple Flask app if it doesn't exist
if [ ! -f "$PROJECT_DIR/app.py" ]; then
    echo "Creating example Flask app..."
    cat > "$PROJECT_DIR/app.py"  "$PROJECT_DIR/requirements.txt"  "$PROJECT_DIR/.env.example"  "$PROJECT_DIR/start.sh"