# Copyright (c) 2017 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Inputs
Download all data.
"""

import re
import gzip
import logging

from os import rename, remove
from os.path import join, getsize
from shutil import move
from zipfile import ZipFile, is_zipfile, BadZipfile

from httplib import responses
from requests import get, codes, RequestException, Timeout, TooManyRedirects, \
    HTTPError, ConnectionError

from errors import PresentationError


# Chunk size used for file download
CHUNK_SIZE = 512

# Separator used in file names
SEPARATOR = "__"

REGEX_RELEASE = re.compile(r'(\D*)(\d{4}|master)(\D*)')


def download_data_files(spec):
    """Download all data specified in the specification file in the section
    type: input --> builds.

    :param spec: Specification.
    :type spec: Specification
    :raises: PresentationError if there is no url defined for the job.
    """

    for job, builds in spec.builds.items():
        for build in builds:
            if job.startswith("csit-"):
                if spec.input["file-name"].endswith(".zip"):
                    url = spec.environment["urls"]["URL[JENKINS,CSIT]"]
                elif spec.input["file-name"].endswith(".gz"):
                    url = spec.environment["urls"]["URL[NEXUS,LOG]"]
                else:
                    logging.error("Not supported file format.")
                    continue
            elif job.startswith("hc2vpp-"):
                url = spec.environment["urls"]["URL[JENKINS,HC]"]
            else:
                raise PresentationError("No url defined for the job '{}'.".
                                        format(job))
            file_name = spec.input["file-name"]
            full_name = spec.input["download-path"].\
                format(job=job, build=build["build"], filename=file_name)
            url = "{0}/{1}".format(url, full_name)
            new_name = join(
                spec.environment["paths"]["DIR[WORKING,DATA]"],
                "{job}{sep}{build}{sep}{name}".format(job=job,
                                                      sep=SEPARATOR,
                                                      build=build["build"],
                                                      name=file_name))
            logging.info(
                "Downloading the file '{0}' to '{1}' ...".format(url, new_name))

            status = "failed"
            try:
                response = get(url, stream=True)
                code = response.status_code
                if code != codes["OK"]:
                    logging.warning(
                        "Jenkins: {0}: {1}.".format(code, responses[code]))
                    logging.info("Trying to download from Nexus:")
                    spec.set_input_state(job, build["build"], "not found")
                    if code == codes["not_found"]:
                        release = re.search(REGEX_RELEASE, job).group(2)
                        nexus_file_name = "{job}{sep}{build}{sep}{name}".\
                            format(job=job, sep=SEPARATOR, build=build["build"],
                                   name=file_name)
                        try:
                            release = "rls".format(int(release))
                        except ValueError:
                            pass
                        url = "{url}/{release}/{dir}/{file}".\
                            format(url=spec.environment["urls"]["URL[NEXUS]"],
                                   release=release,
                                   dir=spec.environment["urls"]["DIR[NEXUS]"],
                                   file=nexus_file_name)
                        logging.info("Downloading the file '{0}' to '{1}' ...".
                                     format(url, new_name))
                        response = get(url, stream=True)
                        code = response.status_code
                        if code != codes["OK"]:
                            logging.error(
                                "Nexus: {0}: {1}".format(code, responses[code]))
                            spec.set_input_state(
                                job, build["build"], "not found")
                            continue

                file_handle = open(new_name, "wb")
                for chunk in response.iter_content(chunk_size=CHUNK_SIZE):
                    if chunk:
                        file_handle.write(chunk)
                file_handle.close()

                if spec.input["file-name"].endswith(".zip"):
                    expected_length = None
                    try:
                        expected_length = int(response.
                                              headers["Content-Length"])
                        logging.debug("  Expected file size: {0}B".
                                      format(expected_length))
                    except KeyError:
                        logging.debug("  No information about expected size.")

                    real_length = getsize(new_name)
                    logging.debug("  Downloaded size: {0}B".format(real_length))

                    if expected_length:
                        if real_length == expected_length:
                            status = "downloaded"
                            logging.info("{0}: {1}".format(code,
                                                           responses[code]))
                        else:
                            logging.error("The file size differs from the "
                                          "expected size.")
                    else:
                        status = "downloaded"
                        logging.info("{0}: {1}".format(code, responses[code]))

                elif spec.input["file-name"].endswith(".gz"):
                    rename(new_name, new_name[:-3])
                    with open(new_name[:-3], 'r') as xml_file:
                        with gzip.open(new_name, 'wb') as gz_file:
                            gz_file.write(xml_file.read())
                    new_name = new_name[:-3]
                    status = "downloaded"
                    logging.info("{0}: {1}".format(code, responses[code]))

            except ConnectionError as err:
                logging.error("Not possible to connect to '{0}'.".format(url))
                logging.debug(err)
            except HTTPError as err:
                logging.error("Invalid HTTP response from '{0}'.".format(url))
                logging.debug(err)
            except TooManyRedirects as err:
                logging.error("Request exceeded the configured number "
                              "of maximum re-directions.")
                logging.debug(err)
            except Timeout as err:
                logging.error("Request timed out.")
                logging.debug(err)
            except RequestException as err:
                logging.error("Unexpected HTTP request exception.")
                logging.debug(err)
            except (IOError, ValueError, KeyError) as err:
                logging.error("Download failed.")
                logging.debug("Reason: {0}".format(err))

            spec.set_input_state(job, build["build"], status)
            spec.set_input_file_name(job, build["build"], new_name)

            if status == "failed":
                logging.info("Removing the file '{0}'".format(new_name))
                try:
                    remove(new_name)
                except OSError as err:
                    logging.warning(str(err))
                spec.set_input_file_name(job, build["build"], None)

    unzip_files(spec)


def unzip_files(spec):
    """Unzip downloaded zip files

    :param spec: Specification.
    :type spec: Specification
    :raises: PresentationError if the zip file does not exist or it is not a
    zip file.
    """

    if spec.is_debug:
        data_file = spec.debug["extract"]
    else:
        data_file = spec.input["extract"]

    for job, builds in spec.builds.items():
        for build in builds:
            if build["status"] == "failed" or build["status"] == "not found":
                continue
            try:
                status = "failed"
                directory = spec.environment["paths"]["DIR[WORKING,DATA]"]
                file_name = join(build["file-name"])

                if build["status"] == "downloaded":
                    logging.info("Unziping: '{0}' from '{1}'.".
                                 format(data_file, file_name))
                    new_name = "{0}{1}{2}".format(file_name.rsplit('.')[-2],
                                                  SEPARATOR,
                                                  data_file.split("/")[-1])
                    try:
                        if is_zipfile(file_name):
                            with ZipFile(file_name, 'r') as zip_file:
                                zip_file.extract(data_file, directory)
                            logging.info("Moving {0} to {1} ...".
                                         format(join(directory, data_file),
                                                directory))
                            move(join(directory, data_file), directory)
                            logging.info("Renaming the file '{0}' to '{1}'".
                                         format(join(directory,
                                                     data_file.split("/")[-1]),
                                                new_name))
                            rename(join(directory, data_file.split("/")[-1]),
                                   new_name)
                            spec.set_input_file_name(job, build["build"],
                                                     new_name)
                        status = "unzipped"
                        spec.set_input_state(job, build["build"], status)
                    except (BadZipfile, RuntimeError) as err:
                        logging.error("Failed to unzip the file '{0}': {1}.".
                                      format(file_name, str(err)))
                    except OSError as err:
                        logging.error("Failed to rename the file '{0}': {1}.".
                                      format(data_file, str(err)))
                    finally:
                        if status == "failed":
                            spec.set_input_file_name(job, build["build"], None)
                else:
                    raise PresentationError("The file '{0}' does not exist or "
                                            "it is not a zip file".
                                            format(file_name))

                spec.set_input_state(job, build["build"], status)

            except KeyError:
                pass