#!/bin/bash

# Environment Setup Script for Formal Specification Generation System
# This script initializes the development environment and checks dependencies

set -e  # Exit on any error

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# Function to print colored output
print_status() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

print_success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1"
}

print_warning() {
    echo -e "${YELLOW}[WARNING]${NC} $1"
}

print_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Function to check if command exists
command_exists() {
    command -v "$1" >/dev/null 2>&1
}

# Function to check Python version
check_python() {
    print_status "Checking Python installation..."

    if ! command_exists python3; then
        print_error "Python 3 is not installed. Please install Python 3.8 or later."
        exit 1
    fi

    PYTHON_VERSION=$(python3 -c 'import sys; print(".".join(map(str, sys.version_info[:2])))')
    REQUIRED_VERSION="3.8"

    if python3 -c "import sys; exit(0 if sys.version_info >= (3, 8) else 1)"; then
        print_success "Python $PYTHON_VERSION found (>= $REQUIRED_VERSION)"
    else
        print_error "Python $PYTHON_VERSION found, but $REQUIRED_VERSION or later is required"
        exit 1
    fi
}

# Function to check CBMC installation
check_cbmc() {
    print_status "Checking CBMC installation..."

    if ! command_exists cbmc; then
        print_warning "CBMC is not installed or not in PATH"
        print_status "Please install CBMC 5.0 or later:"
        echo "  - Ubuntu/Debian: sudo apt-get install cbmc"
        echo "  - Or download from: https://github.com/diffblue/cbmc"
        echo "  - Make sure cbmc is in your PATH"
        return 1
    fi

    CBMC_VERSION=$(cbmc --version 2>/dev/null | head -n1 || echo "unknown")
    print_success "CBMC found: $CBMC_VERSION"
}

# Function to check pip
check_pip() {
    print_status "Checking pip installation..."

    if ! command_exists pip3; then
        print_error "pip3 is not installed. Please install pip for Python 3."
        exit 1
    fi

    print_success "pip3 found"
}

# Function to create virtual environment
create_venv() {
    print_status "Creating virtual environment..."

    if [ -d "venv" ]; then
        print_warning "Virtual environment already exists"
        return 0
    fi

    python3 -m venv venv
    print_success "Virtual environment created"
}

# Function to activate virtual environment and install dependencies
install_dependencies() {
    print_status "Installing Python dependencies..."

    # Activate virtual environment
    source venv/bin/activate

    # Upgrade pip
    pip install --upgrade pip

    # Install requirements
    if [ -f "requirements.txt" ]; then
        pip install -r requirements.txt
        print_success "Dependencies installed from requirements.txt"
    else
        print_error "requirements.txt not found"
        exit 1
    fi
}

# Function to create necessary directories
create_directories() {
    print_status "Creating necessary directories..."

    directories=(
        "logs"
        "uploads"
        "config"
        "cbmc/proofs"
        "cbmc/harnesses"
        "cbmc/configs"
        "results"
        "temp"
    )

    for dir in "${directories[@]}"; do
        if [ ! -d "$dir" ]; then
            mkdir -p "$dir"
            print_status "Created directory: $dir"
        fi
    done

    print_success "All directories created"
}

# Function to create .env file
create_env_file() {
    print_status "Creating environment configuration..."

    if [ ! -f ".env" ]; then
        if [ -f ".env.template" ]; then
            cp .env.template .env
            print_success "Created .env file from template"
            print_warning "Please edit .env file and add your SiliconFlow API key"
        else
            print_error ".env.template not found"
            exit 1
        fi
    else
        print_warning ".env file already exists"
    fi
}

# Function to validate configuration
validate_config() {
    print_status "Validating configuration..."

    # Check if .env file exists
    if [ ! -f ".env" ]; then
        print_error ".env file not found. Please create it from .env.template"
        return 1
    fi

    # Source .env file to check environment variables
    source .env

    # Check required environment variables
    required_vars=(
        "SILICONFLOW_API_KEY"
    )

    missing_vars=()
    for var in "${required_vars[@]}"; do
        if [ -z "${!var}" ]; then
            missing_vars+=("$var")
        fi
    done

    if [ ${#missing_vars[@]} -gt 0 ]; then
        print_error "Missing required environment variables:"
        for var in "${missing_vars[@]}"; do
            echo "  - $var"
        done
        print_warning "Please add these variables to your .env file"
        return 1
    fi

    print_success "Configuration validation passed"
}

# Function to run basic tests
run_tests() {
    print_status "Running basic tests..."

    # Activate virtual environment
    source venv/bin/activate

    # Run Python import tests
    python -c "
import sys
sys.path.insert(0, 'src')
try:
    from utils.config import get_config
    from utils.logger import get_logger
    print('✓ Core utilities import successful')

    config = get_config()
    print('✓ Configuration loading successful')

    logger = get_logger('test')
    logger.info('Test message')
    print('✓ Logging system working')

except ImportError as e:
    print(f'✗ Import error: {e}')
    sys.exit(1)
except Exception as e:
    print(f'✗ Error: {e}')
    sys.exit(1)
"

    if [ $? -eq 0 ]; then
        print_success "Basic tests passed"
    else
        print_error "Basic tests failed"
        return 1
    fi
}

# Function to show usage information
show_usage() {
    echo "Usage: $0 [OPTIONS]"
    echo ""
    echo "Options:"
    echo "  -h, --help          Show this help message"
    echo "  -f, --force         Force recreation of virtual environment"
    echo "  -s, --skip-tests    Skip running tests"
    echo "  -v, --verbose       Verbose output"
    echo ""
    echo "This script sets up the development environment for the Formal"
    echo "Specification Generation System."
}

# Main setup function
main() {
    local force_recreate=false
    local skip_tests=false
    local verbose=false

    # Parse command line arguments
    while [[ $# -gt 0 ]]; do
        case $1 in
            -h|--help)
                show_usage
                exit 0
                ;;
            -f|--force)
                force_recreate=true
                shift
                ;;
            -s|--skip-tests)
                skip_tests=true
                shift
                ;;
            -v|--verbose)
                verbose=true
                set -x  # Enable command tracing
                shift
                ;;
            *)
                print_error "Unknown option: $1"
                show_usage
                exit 1
                ;;
        esac
    done

    print_status "Starting environment setup..."
    print_status "Project: Formal Specification Generation System"
    print_status "=========================================="

    # Check dependencies
    check_python
    check_pip
    check_cbmc

    # Force recreate virtual environment if requested
    if [ "$force_recreate" = true ] && [ -d "venv" ]; then
        print_status "Removing existing virtual environment..."
        rm -rf venv
    fi

    # Setup environment
    create_venv
    install_dependencies
    create_directories
    create_env_file

    # Validate configuration
    if ! validate_config; then
        print_error "Configuration validation failed"
        exit 1
    fi

    # Run tests unless skipped
    if [ "$skip_tests" = false ]; then
        if ! run_tests; then
            print_error "Setup tests failed"
            exit 1
        fi
    fi

    print_success ""
    print_success "Environment setup completed successfully!"
    print_success ""
    print_status "Next steps:"
    echo "  1. Edit .env file to add your API keys if needed"
    echo "  2. Activate virtual environment: source venv/bin/activate"
    echo "  3. (Web UI coming soon) Run the web server: python -m src.ui.web_app"
    echo "  4. Open http://localhost:8080 in your browser"
    echo ""
    print_status "Available now:"
    echo "  - Use CLI: python -m src.ui.cli (once implemented)"
    echo "  - Test core utilities: python -c 'from src.utils.config import get_config; print(\"Config loaded successfully\")'"
    print_success ""
}

# Run main function
main "$@"