from flask import current_app
import docker
import os
import shutil
from app import db, docker_client, scheduler
from app.models import Corpus, CorpusStatus


def handle_corpora():
    with scheduler.app.app_context():
        _handle_corpora()

def _handle_corpora():
    corpora = Corpus.query.all()
    for corpus in [x for x in corpora if x.status == CorpusStatus.SUBMITTED]:
        _create_build_corpus_service(corpus)
    for corpus in [x for x in corpora if x.status in [CorpusStatus.QUEUED, CorpusStatus.BUILDING]]:
        _checkout_build_corpus_service(corpus)
    for corpus in [x for x in corpora if x.status == CorpusStatus.BUILT and x.num_analysis_sessions > 0]:
        corpus.status = CorpusStatus.STARTING_ANALYSIS_SESSION
    for corpus in [x for x in corpora if x.status == CorpusStatus.RUNNING_ANALYSIS_SESSION and x.num_analysis_sessions == 0]:
        corpus.status = CorpusStatus.CANCELING_ANALYSIS_SESSION
    for corpus in [x for x in corpora if x.status == CorpusStatus.RUNNING_ANALYSIS_SESSION]:
        _checkout_cqpserver_container(corpus)
    for corpus in [x for x in corpora if x.status == CorpusStatus.STARTING_ANALYSIS_SESSION]:
        _create_cqpserver_container(corpus)
    for corpus in [x for x in corpora if x.status == CorpusStatus.CANCELING_ANALYSIS_SESSION]:
        _remove_cqpserver_container(corpus)
    db.session.commit()

def _create_build_corpus_service(corpus: Corpus):
    ''' # Docker service settings # '''
    ''' ## Command ## '''
    command = ['bash', '-c']
    command.append(
        f'mkdir /corpora/data/nopaque-{corpus.hashid.lower()}'
        ' && '
        'cwb-encode'
        ' -c utf8'
        f' -d /corpora/data/nopaque-{corpus.hashid.lower()}'
        ' -f /root/files/corpus.vrt'
        f' -R /usr/local/share/cwb/registry/nopaque-{corpus.hashid.lower()}'
        ' -P pos -P lemma -P simple_pos'
        ' -S ent:0+type -S s:0'
        ' -S text:0+address+author+booktitle+chapter+editor+institution+journal+pages+publisher+publishing_year+school+title'
        ' -xsB -9'
        ' && '
        f'cwb-make -V NOPAQUE-{corpus.hashid.upper()}'
    )
    ''' ## Constraints ## '''
    constraints = ['node.role==worker']
    ''' ## Image ## '''
    image = f'{current_app.config["NOPAQUE_DOCKER_IMAGE_PREFIX"]}cwb:r1887'
    ''' ## Labels ## '''
    labels = {
        'nopaque.server_name': current_app.config['SERVER_NAME']
    }
    ''' ## Mounts ## '''
    mounts = []
    ''' ### Data mount ### '''
    data_mount_source = os.path.join(corpus.path, 'cwb', 'data')
    data_mount_target = '/corpora/data'
    data_mount = f'{data_mount_source}:{data_mount_target}:rw'
    # Make sure that their is no data in the data directory
    shutil.rmtree(data_mount_source, ignore_errors=True)
    os.makedirs(data_mount_source)
    mounts.append(data_mount)
    ''' ### File mount ### '''
    file_mount_source = os.path.join(corpus.path, 'cwb', 'corpus.vrt')
    file_mount_target = '/root/files/corpus.vrt'
    file_mount = f'{file_mount_source}:{file_mount_target}:ro'
    mounts.append(file_mount)
    ''' ### Registry mount ### '''
    registry_mount_source = os.path.join(corpus.path, 'cwb', 'registry')
    registry_mount_target = '/usr/local/share/cwb/registry'
    registry_mount = f'{registry_mount_source}:{registry_mount_target}:rw'
    # Make sure that their is no data in the registry directory
    shutil.rmtree(registry_mount_source, ignore_errors=True)
    os.makedirs(registry_mount_source)
    mounts.append(registry_mount)
    ''' ## Name ## '''
    name = f'build-corpus_{corpus.id}'
    ''' ## Restart policy ## '''
    restart_policy = docker.types.RestartPolicy()
    try:
        docker_client.services.create(
            image,
            command=command,
            constraints=constraints,
            labels=labels,
            mounts=mounts,
            name=name,
            restart_policy=restart_policy,
            user='0:0'
        )
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Create service "{name}" failed: {e}')
        return
    corpus.status = CorpusStatus.QUEUED

def _checkout_build_corpus_service(corpus: Corpus):
    service_name = f'build-corpus_{corpus.id}'
    try:
        service = docker_client.services.get(service_name)
    except docker.errors.NotFound as e:
        current_app.logger.error(f'Get service "{service_name}" failed: {e}')
        corpus.status = CorpusStatus.FAILED
        return
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Get service "{service_name}" failed: {e}')
    service_tasks = service.tasks()
    if not service_tasks:
        return
    task_state = service_tasks[0].get('Status').get('State')
    if corpus.status == CorpusStatus.QUEUED and task_state != 'pending':
        corpus.status = CorpusStatus.BUILDING
        return
    elif corpus.status == CorpusStatus.BUILDING and task_state == 'complete':
        corpus.status = CorpusStatus.BUILT
    elif corpus.status == CorpusStatus.BUILDING and task_state == 'failed':
        corpus.status = CorpusStatus.FAILED
    else:
        return
    try:
        service.remove()
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Remove service "{service_name}" failed: {e}')

def _create_cqpserver_container(corpus: Corpus):
    ''' ## Command ## '''
    command = []
    command.append(
        'echo "host *;" > cqpserver.init'
        ' && '
        'echo "user anonymous \\"\\";" >> cqpserver.init'
        ' && '
        'cqpserver -I cqpserver.init'
    )
    ''' ## Detach ## '''
    detach = True
    ''' ## Entrypoint ## '''
    entrypoint = ['bash', '-c']
    ''' ## Image ## '''
    image = f'{current_app.config["NOPAQUE_DOCKER_IMAGE_PREFIX"]}cwb:r1887'
    ''' ## Name ## '''
    name = f'nopaque-cqpserver-{corpus.id}'
    ''' ## Network ## '''
    network = f'{current_app.config["NOPAQUE_DOCKER_NETWORK_NAME"]}'
    ''' ## Volumes ## '''
    volumes = []
    ''' ### Corpus data volume ### '''
    data_volume_source = os.path.join(corpus.path, 'cwb', 'data')
    data_volume_target = '/corpora/data'
    # data_volume_source = os.path.join(corpus.path, 'cwb', 'data', f'nopaque_{corpus.id}')
    # data_volume_target = f'/corpora/data/nopaque_{corpus.hashid.lower()}'
    data_volume = f'{data_volume_source}:{data_volume_target}:rw'
    volumes.append(data_volume)
    ''' ### Corpus registry volume ### '''
    registry_volume_source = os.path.join(corpus.path, 'cwb', 'registry')
    registry_volume_target = '/usr/local/share/cwb/registry'
    # registry_volume_source = os.path.join(corpus.path, 'cwb', 'registry', f'nopaque_{corpus.id}')
    # registry_volume_target = f'/usr/local/share/cwb/registry/nopaque_{corpus.hashid.lower()}'
    registry_volume = f'{registry_volume_source}:{registry_volume_target}:rw'
    volumes.append(registry_volume)
    # Check if a cqpserver container already exists. If this is the case,
    # remove it and create a new one
    try:
        container = docker_client.containers.get(name)
    except docker.errors.NotFound:
        pass
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Get container "{name}" failed: {e}')
        return
    else:
        try:
            container.remove(force=True)
        except docker.errors.DockerException as e:
            current_app.logger.error(f'Remove container "{name}" failed: {e}')
            return
    try:
        docker_client.containers.run(
            image,
            command=command,
            detach=detach,
            entrypoint=entrypoint,
            name=name,
            network=network,
            user='0:0',
            volumes=volumes
        )
    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 = CorpusStatus.FAILED
        return
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Run container "{name}" failed: {e}')
        return
    corpus.status = CorpusStatus.RUNNING_ANALYSIS_SESSION

def _checkout_cqpserver_container(corpus: Corpus):
    container_name = f'nopaque-cqpserver-{corpus.id}'
    try:
        docker_client.containers.get(container_name)
    except docker.errors.NotFound as e:
        current_app.logger.error(f'Get container "{container_name}" failed: {e}')
        corpus.num_analysis_sessions = 0
        corpus.status = CorpusStatus.BUILT
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Get container "{container_name}" failed: {e}')

def _remove_cqpserver_container(corpus: Corpus):
    container_name = f'nopaque-cqpserver-{corpus.id}'
    try:
        container = docker_client.containers.get(container_name)
    except docker.errors.NotFound:
        corpus.status = CorpusStatus.BUILT
        return
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Get container "{container_name}" failed: {e}')
        return
    try:
        container.remove(force=True)
    except docker.errors.DockerException as e:
        current_app.logger.error(f'Remove container "{container_name}" failed: {e}')