#!/bin/zsh
while [[ "$#" -gt 0 ]]
do 
  case $1 in
    --app_name) app_name="$2"
    shift;;
    *) echo "Unknown parameter passed: $1"
    exit 1;;
  esac
  shift
done

# Make sure app_name exists and is not empty
if [[ -z "$app_name" ]]; then
  echo "app_name is unset or empty."
  exit 1;
fi

# Define the base directory for the new application structure
# This will be one level up from where this script is executed.
app_base_dir="../${app_name}"
app_data_dir="${app_base_dir}/data"
compose_file="${app_base_dir}/compose.yaml"
readme_file="${app_base_dir}/README.md"
start_script="${app_base_dir}/start.sh"

echo "--- Setting up files and directories for application: ${app_name} ---"
echo "Base directory: ${app_base_dir}"

# 1. Create the application base directory and data directory
echo "Creating directory: ${app_data_dir}"
mkdir -p "${app_data_dir}" || { echo "Error: Failed to create directory ${app_data_dir}"; exit 1; }

# 2. Create compose.yaml and README.md
echo "Creating file: ${compose_file}"
touch "${compose_file}" || { echo "Error: Failed to create file ${compose_file}"; exit 1; }

echo "Creating file: ${readme_file}"
touch "${readme_file}" || { echo "Error: Failed to create file ${readme_file}"; exit 1; }

# 3. Prepopulate README.md with title case app name
# Convert app_name to title case (first letter of each word capitalized)
# This is a simple conversion; for more robust title casing, a function would be better.
app_name_title_case=$(echo "$app_name" | awk '{for(i=1;i<=NF;i++){ $i=toupper(substr($i,1,1)) tolower(substr($i,2)) }}1')

echo "Prepopulating ${readme_file}..."
cat > "${readme_file}" << EOF
# ${app_name_title_case}

This is the README file for the **${app_name}** application.

## Overview
Provide a brief description of your application here.

## Setup
Instructions for setting up the application.

EOF

# 4. Ask the user if secrets will be required
read "requires_secrets?Will this application require secrets (yes/no)? "
requires_secrets=$(echo "$requires_secrets" | tr '[:upper:]' '[:lower:]') # Convert to lowercase

# 5. Prepopulate compose.yaml based on user selection re. secrets
echo "Prepopulating ${compose_file} based on secrets requirement..."
if [[ "$requires_secrets" == "yes" || "$requires_secrets" == "y" ]]; then
  cat > "${compose_file}" << EOF
version: '3.8'
services:
  ${app_name}:
    image: your-app-image:latest
    container_name: ${app_name}-container
    ports:
      - "8080:8080"
    volumes:
      - ./data:/app/data
    environment:
      # Example of how to pass secrets as environment variables
      # These would typically be loaded from a .env file or a secrets management system
      - DATABASE_URL=\${DATABASE_URL}
      - API_KEY=\${API_KEY}
    # Example of secrets usage with Docker Compose secrets (requires Docker Swarm or specific setup)
    # secrets:
    #   - my_database_password
    #   - my_api_key
    # deploy:
    #   resources:
    #     limits:
    #       cpus: '0.5'
    #       memory: 512M
secrets:
  my_database_password:
    external: true # Assumes secret is created externally (e.g., docker secret create)
  my_api_key:
    external: true
EOF
else
  cat > "${compose_file}" << EOF
services:
  ${app_name}:
    image: your-app-image:latest
    container_name: ${app_name}-container
    ports:
      - "8080:8080"
    volumes:
      - ./data:/app/data
    # No secrets configuration needed for this version
    # deploy:
    #   resources:
    #     limits:
    #       cpus: '0.5'
    #       memory: 512M
EOF
fi

# 6. If secrets will be used - touch ../"app_name"/start.sh and prepopulate it
if [[ "$requires_secrets" == "yes" || "$requires_secrets" == "y" ]]; then
  echo "Creating and prepopulating ${start_script}..."
  cat > "${start_script}" << EOF
#!/bin/zsh

# Example start script for an application using secrets
# This script assumes you have a .env file or similar mechanism
# for loading secrets into the environment before starting Docker Compose.

# --- IMPORTANT: Replace with your actual secret loading mechanism ---
# Example 1: Load from a .env file
# if [[ -f ".env" ]]; then
#   echo "Loading environment variables from .env"
#   source .env
# else
#   echo "Warning: .env file not found. Secrets might be missing."
# fi

# Example 2: Using a secrets management tool (e.g., HashiCorp Vault, AWS Secrets Manager)
# echo "Fetching secrets from Vault..."
# export DATABASE_URL=\$(vault read -field=value secret/myapp/database_url)
# export API_KEY=\$(vault read -field=value secret/myapp/api_key)
# -------------------------------------------------------------------

echo "Starting Docker Compose services for ${app_name}..."
docker compose -f "${compose_file}" up -d

echo "Application ${app_name} started. Check logs with: docker compose logs -f ${app_name}"
EOF
  chmod +x "${start_script}" # Make the start script executable
fi

# 7. If secrets will be used, append another chapter at the end of the README.md file
if [[ "$requires_secrets" == "yes" || "$requires_secrets" == "y" ]]; then
  echo "Appending 'Secrets Management' chapter to ${readme_file}..."
  cat >> "${readme_file}" << EOF

## Secrets Management

This application utilizes secrets for sensitive configurations (e.g., database credentials, API keys).

### Configuration
Secrets are expected to be provided via environment variables or Docker Compose secrets.
Refer to the \`start.sh\` script for an example of how to load these secrets before application startup.

**Example Environment Variables (to be set in your environment or a \`.env\` file):**
\`\`\`
DATABASE_URL="postgres://user:password@host:port/database"
API_KEY="your_super_secret_api_key"
\`\`\`

**For Docker Compose secrets:**
Ensure the necessary Docker secrets are created on your Docker host or Swarm cluster.
\`\`\`bash
docker secret create my_database_password <(echo "your_db_password")
docker secret create my_api_key <(echo "your_api_key")
\`\`\`
Then, update the \`compose.yaml\` to reference these secrets.

EOF
fi

echo "--- Setup complete for ${app_name} ---"
echo "Check the '${app_base_dir}' directory for your new files."