#!/bin/bash

# Install Python 3.12 on Amazon Linux (without sudo)
# This script attempts to install Python 3.12 in user space

set -e

echo "🐍 Installing Python 3.12 for AWS Lambda Layers..."

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

print_status() {
    echo -e "${GREEN}[INFO]${NC} $1"
}

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

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

# Check if we already have Python 3.12
if command -v python3.12 &> /dev/null; then
    print_status "Python 3.12 is already available: $(python3.12 --version)"
    exit 0
fi

# Try to install Python 3.12 using package manager first
print_status "Attempting to install Python 3.12 using package manager..."

# For Amazon Linux 2023
if [ -f /etc/os-release ]; then
    source /etc/os-release
    if [[ "$NAME" == *"Amazon Linux"* ]]; then
        print_status "Detected Amazon Linux"
        
        # Try with dnf (Amazon Linux 2023)
        if command -v dnf &> /dev/null; then
            print_status "Using dnf to install Python 3.12..."
            dnf install -y python3.12 python3.12-pip python3.12-devel || {
                print_warning "Failed to install Python 3.12 via dnf"
            }
        # Try with yum (Amazon Linux 2)
        elif command -v yum &> /dev/null; then
            print_status "Using yum to install Python 3.12..."
            yum install -y python3.12 python3.12-pip python3.12-devel || {
                print_warning "Failed to install Python 3.12 via yum"
            }
        fi
    fi
fi

# Check if installation was successful
if command -v python3.12 &> /dev/null; then
    print_status "✅ Python 3.12 installed successfully: $(python3.12 --version)"
    
    # Create symlinks if they don't exist
    if [ ! -f /usr/bin/python3.12 ]; then
        which python3.12 > /dev/null && ln -sf $(which python3.12) /usr/local/bin/python3.12 || true
    fi
    
    # Set alternatives
    if command -v alternatives &> /dev/null; then
        alternatives --install /usr/bin/python3 python3 /usr/bin/python3.12 1 || true
        alternatives --install /usr/bin/pip3 pip3 /usr/bin/pip3.12 1 || true
    fi
    
    exit 0
fi

# If package manager installation failed, try building from source
print_warning "Package manager installation failed. Attempting to build from source..."

# Create a local installation directory
PYTHON_HOME="$HOME/.local/python3.12"
mkdir -p $PYTHON_HOME

# Download Python 3.12 source
PYTHON_VERSION="3.12.2"
PYTHON_URL="https://www.python.org/ftp/python/${PYTHON_VERSION}/Python-${PYTHON_VERSION}.tgz"

print_status "Downloading Python ${PYTHON_VERSION}..."
cd /tmp
wget $PYTHON_URL
tar -xzf Python-${PYTHON_VERSION}.tgz
cd Python-${PYTHON_VERSION}

# Configure and build
print_status "Configuring Python build..."
./configure --prefix=$PYTHON_HOME \
    --enable-optimizations \
    --enable-shared \
    --with-ensurepip=install

print_status "Building Python (this may take a while)..."
make -j$(nproc)

print_status "Installing Python to ${PYTHON_HOME}..."
make install

# Create symlinks
ln -sf $PYTHON_HOME/bin/python3.12 $HOME/.local/bin/python3.12
ln -sf $PYTHON_HOME/bin/pip3.12 $HOME/.local/bin/pip3.12

# Add to PATH
echo "export PATH=$HOME/.local/bin:$PATH" >> $HOME/.bashrc
export PATH=$HOME/.local/bin:$PATH

# Verify installation
if command -v python3.12 &> /dev/null; then
    print_status "✅ Python 3.12 built and installed successfully!"
    print_status "Version: $(python3.12 --version)"
    print_status "Location: $(which python3.12)"
else
    print_error "❌ Failed to install Python 3.12"
    exit 1
fi

# Clean up
cd $HOME
rm -rf /tmp/Python-${PYTHON_VERSION}*

print_status "🎉 Python 3.12 is ready to use!"
print_status "Run 'source ~/.bashrc' or restart your shell to update PATH"