from ..models import Corpus
import docker
import logging
import os
import shutil


class CheckCorporaMixin:
    def check_corpora(self):
        corpora = Corpus.query.all()
        queued_corpora = list(filter(lambda corpus: corpus.status == 'queued', corpora))  # noqa
        running_corpora = list(filter(lambda corpus: corpus.status == 'running', corpora))  # noqa
        start_analysis_corpora = list(filter(lambda corpus: corpus.status == 'start analysis', corpora))  # noqa
        analysing_corpora = list(filter(lambda corpus: corpus.status == 'analysing', corpora))  # noqa
        stop_analysis_corpora = list(filter(lambda corpus: corpus.status == 'stop analysis', corpora))  # noqa
        submitted_corpora = list(filter(lambda corpus: corpus.status == 'submitted', corpora))  # noqa
        for corpus in submitted_corpora:
            self.create_build_corpus_service(corpus)
        for corpus in queued_corpora + running_corpora:
            self.checkout_build_corpus_service(corpus)
        for corpus in start_analysis_corpora:
            self.create_cqpserver_container(corpus)
        for corpus in analysing_corpora:
            self.checkout_analysing_corpus_container(corpus)
        for corpus in stop_analysis_corpora:
            self.remove_cqpserver_container(corpus)

    def create_build_corpus_service(self, corpus):
        corpus_data_dir = os.path.join(corpus.path, 'data')
        shutil.rmtree(corpus_data_dir, ignore_errors=True)
        os.mkdir(corpus_data_dir)
        corpus_registry_dir = os.path.join(corpus.path, 'registry')
        shutil.rmtree(corpus_registry_dir, ignore_errors=True)
        os.mkdir(corpus_registry_dir)
        corpus_file = os.path.join(corpus.path, 'merged', 'corpus.vrt')
        service_kwargs = {
            'command': 'docker-entrypoint.sh build-corpus',
            'constraints': ['node.role==worker'],
            'labels': {'origin': 'nopaque',
                       'type': 'corpus.build',
                       'corpus_id': str(corpus.id)},
            'mounts': [corpus_file + ':/root/files/corpus.vrt:ro',
                       corpus_data_dir + ':/corpora/data:rw',
                       corpus_registry_dir + ':/usr/local/share/cwb/registry:rw'],
            'name': 'build-corpus_{}'.format(corpus.id),
            'restart_policy': docker.types.RestartPolicy()
        }
        service_image = \
            'gitlab.ub.uni-bielefeld.de:4567/sfb1288inf/cqpserver:latest'
        try:
            self.docker.services.create(service_image, **service_kwargs)
        except docker.errors.APIError as e:
            logging.error(
                'Create "{}" service raised '.format(service_kwargs['name'])
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
        else:
            corpus.status = 'queued'
            patch_operation = {
                'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
            self.buffer_user_patch_operation(corpus, patch_operation)

    def checkout_build_corpus_service(self, corpus):
        service_name = 'build-corpus_{}'.format(corpus.id)
        try:
            service = self.docker.services.get(service_name)
        except docker.errors.NotFound:
            logging.error(
                'Get "{}" service raised '.format(service_name)
                + '"docker.errors.NotFound" The service does not exist. '
                + '(corpus.status: {} -> failed)'.format(corpus.status)
            )
            corpus.status = 'failed'
            patch_operation = {
                'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
            self.buffer_user_patch_operation(corpus, patch_operation)
        except docker.errors.APIError as e:
            logging.error(
                'Get "{}" service raised '.format(service_name)
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
        except docker.errors.InvalidVersion:
            logging.error(
                'Get "{}" service raised '.format(service_name)
                + '"docker.errors.InvalidVersion" One of the arguments is '
                + 'not supported with the current API version.'
            )
        else:
            service_tasks = service.tasks()
            if not service_tasks:
                return
            task_state = service_tasks[0].get('Status').get('State')
            if corpus.status == 'queued' and task_state != 'pending':
                corpus.status = 'running'
                patch_operation = {
                    'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
                self.buffer_user_patch_operation(corpus, patch_operation)
            elif (corpus.status == 'running'
                  and task_state in ['complete', 'failed']):
                try:
                    service.remove()
                except docker.errors.APIError as e:
                    logging.error(
                        'Remove "{}" service raised '.format(service_name)
                        + '"docker.errors.APIError" The server returned an error. '
                        + 'Details: {}'.format(e)
                    )
                    return
                else:
                    corpus.status = 'prepared' if task_state == 'complete' \
                                    else 'failed'
                    patch_operation = {
                        'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
                    self.buffer_user_patch_operation(corpus, patch_operation)

    def create_cqpserver_container(self, corpus):
        corpus_data_dir = os.path.join(corpus.path, 'data')
        corpus_registry_dir = os.path.join(corpus.path, 'registry')
        container_kwargs = {
            'command': 'cqpserver',
            'detach': True,
            'volumes': [corpus_data_dir + ':/corpora/data:rw',
                        corpus_registry_dir + ':/usr/local/share/cwb/registry:rw'],
            'name': 'cqpserver_{}'.format(corpus.id),
            'network': 'nopaque_default'
        }
        container_image = \
            'gitlab.ub.uni-bielefeld.de:4567/sfb1288inf/cqpserver:latest'
        # Check if a cqpserver container already exists. If this is the case,
        # remove it and create a new one
        try:
            container = self.docker.containers.get(container_kwargs['name'])
        except docker.errors.NotFound:
            pass
        except docker.errors.APIError as e:
            logging.error(
                'Get "{}" container raised '.format(container_kwargs['name'])
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
            return
        else:
            try:
                container.remove(force=True)
            except docker.errors.APIError as e:
                logging.error(
                    'Remove "{}" container raised '.format(
                        container_kwargs['name'])
                    + '"docker.errors.APIError" The server returned an error. '
                    + 'Details: {}'.format(e)
                )
                return
        try:
            self.docker.containers.run(container_image, **container_kwargs)
        except docker.errors.ContainerError:
            # This case should not occur, because detach is True.
            logging.error(
                'Run "{}" container raised '.format(container_kwargs['name'])
                + '"docker.errors.ContainerError" The container exits with a '
                + 'non-zero exit code and detach is False.'
            )
            corpus.status = 'failed'
            patch_operation = {
                'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
            self.buffer_user_patch_operation(corpus, patch_operation)
        except docker.errors.ImageNotFound:
            logging.error(
                'Run "{}" container raised '.format(container_kwargs['name'])
                + '"docker.errors.ImageNotFound" The specified image does not '
                + 'exist.'
            )
            corpus.status = 'failed'
            patch_operation = {
                'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
            self.buffer_user_patch_operation(corpus, patch_operation)
        except docker.errors.APIError as e:
            logging.error(
                'Run "{}" container raised '.format(container_kwargs['name'])
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
        else:
            corpus.status = 'analysing'
            patch_operation = {
                'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
            self.buffer_user_patch_operation(corpus, patch_operation)

    def checkout_analysing_corpus_container(self, corpus):
        container_name = 'cqpserver_{}'.format(corpus.id)
        try:
            self.docker.containers.get(container_name)
        except docker.errors.NotFound:
            logging.error('Could not find "{}" but the corpus state is "analysing".')  # noqa
            corpus.status = 'prepared'
        except docker.errors.APIError as e:
            logging.error(
                'Get "{}" container raised '.format(container_name)
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
            return

    def remove_cqpserver_container(self, corpus):
        container_name = 'cqpserver_{}'.format(corpus.id)
        try:
            container = self.docker.containers.get(container_name)
        except docker.errors.NotFound:
            pass
        except docker.errors.APIError as e:
            logging.error(
                'Get "{}" container raised '.format(container_name)
                + '"docker.errors.APIError" The server returned an error. '
                + 'Details: {}'.format(e)
            )
            return
        else:
            try:
                container.remove(force=True)
            except docker.errors.APIError as e:
                logging.error(
                    'Remove "{}" container raised '.format(container_name)
                    + '"docker.errors.APIError" The server returned an error. '
                    + 'Details: {}'.format(e)
                )
                return
        corpus.status = 'prepared'
        patch_operation = {
            'op': 'replace', 'path': '/corpora/{}/status'.format(corpus.id), 'value': corpus.status}
        self.buffer_user_patch_operation(corpus, patch_operation)