#!/bin/bash

# This script installs the latest Python version and pip on Ubuntu 22.04 LTS

# Function to check for errors
check_error() {
    if [ $? -ne 0 ]; then
        echo "Error: $1"
        exit 1
    fi
}

# Step 1: Update the package list
echo "Updating package list..."
sudo apt update
check_error "Failed to update package list."

# Step 2: Install prerequisite packages
echo "Installing prerequisite packages..."
sudo apt install -y software-properties-common curl
check_error "Failed to install prerequisites."

# Step 3: Add the deadsnakes PPA
echo "Adding deadsnakes PPA for latest Python versions..."
sudo add-apt-repository ppa:deadsnakes/ppa -y
check_error "Failed to add deadsnakes PPA."

# Step 4: Update the package list again after adding the PPA
echo "Updating package list after adding PPA..."
sudo apt update
check_error "Failed to update package list after adding PPA."

# Step 5: Install the latest Python version (e.g., Python 3.11)
PYTHON_VERSION=3.11
echo "Installing Python $PYTHON_VERSION..."
sudo apt install -y python${PYTHON_VERSION}
check_error "Failed to install Python $PYTHON_VERSION."

# Step 6: Set Python 3.x as the default python3 version
echo "Setting Python $PYTHON_VERSION as the default python3..."
sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python${PYTHON_VERSION} 1
check_error "Failed to set Python $PYTHON_VERSION as the default python3."

# Step 7: Install pip
echo "Installing pip for Python $PYTHON_VERSION..."
sudo apt install -y python3-pip
check_error "Failed to install pip."

# If pip is not installed for the latest version, use get-pip.py
if ! command -v pip3 &> /dev/null; then
    echo "Pip not found, downloading get-pip.py..."
    curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
    sudo python${PYTHON_VERSION} get-pip.py
    check_error "Failed to install pip using get-pip.py."
    rm get-pip.py
fi

# Step 8: Verify installation
echo "Verifying Python and pip installation..."
python3 --version
pip3 --version

echo "Python and pip installation completed successfully!"