#!/usr/bin/env python

import argparse
import zipfile
import boto3
import tempfile
import os
import yaml
import json
import stat
import logging
import sys

BASE_DIR = os.path.normpath(os.path.join(os.path.dirname(os.path.abspath(__file__)), '..'))


def fetch_file_path(dpath, root_dir):
    tf = []
    for root, dirs, files in os.walk(dpath):
        for fname in files:
            if not root.endswith('/__pycache__'):
                fpath = os.path.join(root, fname)
                tf.append((fpath, fpath[len(root_dir) + 1:]))

    return tf


def pack_zip_file(config):
    fd1, tpath = tempfile.mkstemp('.zip')
    os.close(fd1)

    target_files = []
    pkg_dir = os.path.normpath(
        os.path.join(os.path.dirname(boto3.__path__[0]), '..')
    )

    target_files = fetch_file_path(pkg_dir, pkg_dir) + \
        fetch_file_path(os.path.join(BASE_DIR, 'bin'), BASE_DIR) + \
        fetch_file_path(os.path.join(BASE_DIR, 'slam'), BASE_DIR)

    with zipfile.ZipFile(tpath, 'w', zipfile.ZIP_DEFLATED) as z:
        for fpath, wpath in target_files:
            if wpath.startswith('boto3-') or wpath.startswith('botocore-'):
                continue

            z.write(fpath, wpath)

        fd2, jpath = tempfile.mkstemp('.json')
        os.write(fd2, json.dumps(config).encode('utf8'))
        os.close(fd2)
        os.chmod(jpath, stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH)
        z.write(jpath, 'config.json')

    return tpath


def configure_lambda(client, raw_data, config):
    logger.info('configure {} -> {}'.format(config['script-name'],
                                            config['function-name']))
    code_res = client.update_function_code(
        FunctionName=config['function-name'],
        ZipFile=raw_data,
    )
    logger.debug('  Upload code: %s', json.dumps(code_res, indent=4))

    conf_res = client.update_function_configuration(
        FunctionName=config['function-name'],
        Handler='bin.{}.lambda_handler'.format(config['script-name']),
        Timeout=config.get('timeout', 60),
        MemorySize=config.get('memory', 128),
        Runtime='python3.6'
    )
    logger.debug('  Update config: %s', json.dumps(conf_res, indent=4))


def main():
    psr = argparse.ArgumentParser()
    psr.add_argument('-c', '--config',
                     default=os.path.join(BASE_DIR, 'config.yml'), type=open)
    args = psr.parse_args()

    config = yaml.load(args.config)

    zip_fpath = pack_zip_file(config)

    client = boto3.client('lambda')


    raw_data = open(zip_fpath, 'rb').read()
    for func in config['functions']:
        configure_lambda(client, raw_data, func)



if __name__ == '__main__':
    logger = logging.getLogger()
    logger.setLevel(logging.INFO)
    logger.addHandler(logging.StreamHandler(sys.stdout))
    main()