from flask import current_app
from ..models import Corpus
import docker
import os
import shutil


class CheckCorporaMixin:
    def check_corpora(self):
        corpora = Corpus.query.all()
        for corpus in (x for x in corpora if x.status == 'submitted'):
            self.create_build_corpus_service(corpus)
        for corpus in (x for x in corpora if x.status == 'queued' or x.status == 'running'):  # noqa
            self.checkout_build_corpus_service(corpus)
        for corpus in (x for x in corpora if x.status == 'prepared' and x.num_analysis_sessions > 0):  # noqa
            corpus.status = 'start analysis'
        for corpus in (x for x in corpora if x.status == 'analysing' and x.num_analysis_sessions == 0):  # noqa
            corpus.status = 'stop analysis'
        for corpus in (x for x in corpora if x.status == 'analysing'):
            self.checkout_analysing_corpus_container(corpus)
        for corpus in (x for x in corpora if x.status == 'start analysis'):
            self.create_cqpserver_container(corpus)
        for corpus in (x for x in corpora if x.status == 'stop analysis'):
            self.remove_cqpserver_container(corpus)

    def create_build_corpus_service(self, corpus):
        ''' # Docker service settings # '''
        ''' ## Command ## '''
        command = 'docker-entrypoint.sh build-corpus'
        ''' ## Constraints ## '''
        constraints = ['node.role==worker']
        ''' ## Image ## '''
        image = f'{current_app.config["NOPAQUE_DOCKER_IMAGE_PREFIX"]}cqpserver:r1674'  # noqa
        ''' ## Labels ## '''
        labels = {
            'origin': current_app.config['SERVER_NAME'],
            'type': 'build-corpus',
            'corpus_id': str(corpus.id)
        }
        ''' ## Mounts ## '''
        ''' ### Corpus file mount ### '''
        corpus_file_source = os.path.join(corpus.path, 'merged', 'corpus.vrt')
        corpus_file_target = '/root/files/corpus.vrt'
        corpus_file_mount = f'{corpus_file_source}:{corpus_file_target}:ro'
        ''' ### Corpus data mount ### '''
        corpus_data_source = os.path.join(corpus.path, 'data')
        corpus_data_target = '/corpora/data'
        corpus_data_mount = f'{corpus_data_source}:{corpus_data_target}:rw'
        # Make sure that their is no data in the corpus data directory
        shutil.rmtree(corpus_data_source, ignore_errors=True)
        os.mkdir(corpus_data_source)
        ''' ### Corpus registry mount ### '''
        corpus_registry_source = os.path.join(corpus.path, 'registry')
        corpus_registry_target = '/usr/local/share/cwb/registry'
        corpus_registry_mount = f'{corpus_registry_source}:{corpus_registry_target}:rw'  # noqa
        # Make sure that their is no data in the corpus registry directory
        shutil.rmtree(corpus_registry_source, ignore_errors=True)
        os.mkdir(corpus_registry_source)
        mounts = [corpus_file_mount, corpus_data_mount, corpus_registry_mount]
        ''' ## Name ## '''
        name = f'build-corpus_{corpus.id}'
        ''' ## Restart policy ## '''
        restart_policy = docker.types.RestartPolicy()
        try:
            self.docker.services.create(
                image,
                command=command,
                constraints=constraints,
                labels=labels,
                mounts=mounts,
                name=name,
                restart_policy=restart_policy
            )
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Create service "{name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )
            return
        corpus.status = 'queued'

    def checkout_build_corpus_service(self, corpus):
        service_name = f'build-corpus_{corpus.id}'
        try:
            service = self.docker.services.get(service_name)
        except docker.errors.NotFound as e:
            current_app.logger.error(
                f'Get service "{service_name}" failed '
                + f'due to "docker.errors.NotFound": {e}'
            )
            corpus.status = 'failed'
            return
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Get service "{service_name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )
        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'
            return
        elif corpus.status == 'running' and task_state == 'complete':
            corpus.status = 'prepared'
        elif corpus.status == 'running' and task_state == 'failed':
            corpus.status = 'failed'
        else:
            return
        try:
            service.remove()
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Remove service "{service_name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )

    def create_cqpserver_container(self, corpus):
        ''' # Docker container settings # '''
        ''' ## Command ## '''
        command = 'cqpserver'
        ''' ## Detach ## '''
        detach = True
        ''' ## Image ## '''
        image = f'{current_app.config["NOPAQUE_DOCKER_IMAGE_PREFIX"]}cqpserver:r1674'  # noqa
        ''' ## Name ## '''
        name = f'cqpserver_{corpus.id}'
        ''' ## Network ## '''
        network = 'nopaque_default'
        ''' ## Volumes ## '''
        ''' ### Corpus data volume ### '''
        corpus_data_source = os.path.join(corpus.path, 'data')
        corpus_data_target = '/corpora/data'
        corpus_data_volume = f'{corpus_data_source}:{corpus_data_target}:rw'
        ''' ### Corpus registry volume ### '''
        corpus_registry_source = os.path.join(corpus.path, 'registry')
        corpus_registry_target = '/usr/local/share/cwb/registry'
        corpus_registry_volume = f'{corpus_registry_source}:{corpus_registry_target}:rw'  # noqa
        volumes = [corpus_data_volume, corpus_registry_volume]
        # 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(name)
        except docker.errors.NotFound:
            pass
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Get container "{name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )
            return
        else:
            try:
                container.remove(force=True)
            except docker.errors.APIError as e:
                current_app.logger.error(
                    f'Remove container "{name}" failed '
                    + f'due to "docker.errors.APIError": {e}'
                )
                return
        try:
            self.docker.containers.run(
                image,
                command=command,
                detach=detach,
                volumes=volumes,
                name=name,
                network=network
            )
        except docker.errors.ImageNotFound as e:
            current_app.logger.error(
                f'Run container "{name}" failed '
                + f'due to "docker.errors.ImageNotFound" error: {e}'
            )
            corpus.status = 'failed'
            return
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Run container "{name}" failed '
                + f'due to "docker.errors.APIError" error: {e}'
            )
            return
        corpus.status = 'analysing'

    def checkout_analysing_corpus_container(self, corpus):
        container_name = f'cqpserver_{corpus.id}'
        try:
            self.docker.containers.get(container_name)
        except docker.errors.NotFound as e:
            current_app.logger.error(
                f'Get container "{container_name}" failed '
                + f'due to "docker.errors.NotFound": {e}'
            )
            corpus.num_analysis_sessions = 0
            corpus.status = 'prepared'
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Get container "{container_name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )

    def remove_cqpserver_container(self, corpus):
        container_name = f'cqpserver_{corpus.id}'
        try:
            container = self.docker.containers.get(container_name)
        except docker.errors.NotFound:
            corpus.status = 'prepared'
            return
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Get container "{container_name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )
            return
        try:
            container.remove(force=True)
        except docker.errors.APIError as e:
            current_app.logger.error(
                f'Remove container "{container_name}" failed '
                + f'due to "docker.errors.APIError": {e}'
            )