"""AWS Lambda Container Experiment."""

import shlex
import subprocess
import time

import cowsay

CHARACTER = 'cow'


def handler(event, context):
    """Entrypoint."""
    start = time.time()
    if CHARACTER not in cowsay.char_names:
        raise Exception(f'{CHARACTER} not in {cowsay.char_names}')
    result = fibonacci(event['n'])
    getattr(cowsay, CHARACTER)(f'{result:,}')
    command = 'pip list --format=freeze --not-required'
    pip_result = subprocess.run(
        shlex.split(command),
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        encoding='utf-8'
    )
    runtime = time.time() - start
    return {
        'result': result,
        'runtime': runtime,
        'packages': pip_result.stdout.split('\n'),
        'character': CHARACTER
    }


def fibonacci(n):
    """Return fibinacci number in sequence."""
    if n <= 0:
        raise Exception(f'{n} <= 0')
    elif n == 1:
        return 0
    elif n == 2:
        return 1
    else:
        return fibonacci(n - 1) + fibonacci(n - 2)