import os
import shutil
import yaml
from collections import defaultdict

from django.conf import settings
from django.utils import timezone
from django.utils.translation import gettext as _

from common.utils import get_logger
from assets.automations.methods import platform_automation_methods
from ops.ansible import JMSInventory, PlaybookRunner, DefaultCallback

logger = get_logger(__name__)


class PlaybookCallback(DefaultCallback):
    def playbook_on_stats(self, event_data, **kwargs):
        super().playbook_on_stats(event_data, **kwargs)


class BasePlaybookManager:
    bulk_size = 100
    ansible_account_policy = 'privileged_first'

    def __init__(self, execution):
        self.execution = execution
        self.automation = execution.automation
        self.method_id_meta_mapper = {
            method['id']: method
            for method in platform_automation_methods
            if method['method'] == self.__class__.method_type()
        }
        # 根据执行方式就行分组, 不同资产的改密、推送等操作可能会使用不同的执行方式
        # 然后根据执行方式分组, 再根据 bulk_size 分组, 生成不同的 playbook
        # 避免一个 playbook 中包含太多的主机
        self.method_hosts_mapper = defaultdict(list)
        self.playbooks = []

    @classmethod
    def method_type(cls):
        raise NotImplementedError

    def get_assets_group_by_platform(self):
        return self.automation.all_assets_group_by_platform()

    @property
    def runtime_dir(self):
        ansible_dir = settings.ANSIBLE_DIR
        dir_name = '{}_{}'.format(self.automation.name.replace(' ', '_'), self.execution.id)
        path = os.path.join(
            ansible_dir, 'automations', self.automation.type,
            dir_name, timezone.now().strftime('%Y%m%d_%H%M%S')
        )
        if not os.path.exists(path):
            os.makedirs(path, exist_ok=True, mode=0o755)
        return path

    def prepare_playbook_dir(self):
        for d in [self.runtime_dir]:
            if not os.path.exists(d):
                os.makedirs(d, exist_ok=True, mode=0o755)

    def host_callback(self, host, automation=None, **kwargs):
        enabled_attr = '{}_enabled'.format(self.__class__.method_type())
        method_attr = '{}_method'.format(self.__class__.method_type())

        method_enabled = automation and \
            getattr(automation, enabled_attr) and \
            getattr(automation, method_attr) and \
            getattr(automation, method_attr) in self.method_id_meta_mapper

        if not method_enabled:
            host['error'] = _('{} disabled'.format(self.__class__.method_type()))
            return host
        return host

    def generate_inventory(self, platformed_assets, inventory_path):
        inventory = JMSInventory(
            assets=platformed_assets,
            account_policy=self.ansible_account_policy,
            host_callback=self.host_callback
        )
        inventory.write_to_file(inventory_path)

    def generate_playbook(self, platformed_assets, platform, sub_playbook_dir):
        method_id = getattr(platform.automation, '{}_method'.format(self.__class__.method_type()))
        method = self.method_id_meta_mapper.get(method_id)
        if not method:
            logger.error("Method not found: {}".format(method_id))
            return method
        method_playbook_dir_path = method['dir']
        sub_playbook_path = os.path.join(sub_playbook_dir, 'project', 'main.yml')
        shutil.copytree(method_playbook_dir_path, os.path.dirname(sub_playbook_path))

        with open(sub_playbook_path, 'r') as f:
            plays = yaml.safe_load(f)
        for play in plays:
            play['hosts'] = 'all'

        with open(sub_playbook_path, 'w') as f:
            yaml.safe_dump(plays, f)
        return sub_playbook_path

    def get_runners(self):
        runners = []
        for platform, assets in self.get_assets_group_by_platform().items():
            assets_bulked = [assets[i:i+self.bulk_size] for i in range(0, len(assets), self.bulk_size)]

            for i, _assets in enumerate(assets_bulked, start=1):
                sub_dir = '{}_{}'.format(platform.name, i)
                playbook_dir = os.path.join(self.runtime_dir, sub_dir)
                inventory_path = os.path.join(self.runtime_dir, sub_dir, 'hosts.json')
                self.generate_inventory(_assets, inventory_path)
                playbook_path = self.generate_playbook(_assets, platform, playbook_dir)

                runer = PlaybookRunner(
                    inventory_path,
                    playbook_path,
                    self.runtime_dir,
                    callback=PlaybookCallback(),
                )
                runners.append(runer)
        return runners

    def on_host_success(self, host, result):
        pass

    def on_host_error(self, host, error, result):
        pass

    def on_runner_success(self, runner, cb):
        summary = cb.summary
        for state, hosts in summary.items():
            for host in hosts:
                result = cb.host_results.get(host)
                if state == 'ok':
                    self.on_host_success(host, result)
                else:
                    error = hosts.get(host)
                    self.on_host_error(host, error, result)

    def on_runner_failed(self, runner, e):
        print("Runner failed: {} {}".format(e, self))

    def before_runner_start(self, runner):
        print("Start run task: ")
        print("  inventory: {}".format(runner.inventory))
        print("  playbook: {}".format(runner.playbook))

    def run(self,  *args, **kwargs):
        runners = self.get_runners()
        if len(runners) > 1:
            print("### 分批次执行开始任务, 总共 {}\n".format(len(runners)))
        else:
            print(">>> 开始执行任务\n")

        for i, runner in enumerate(runners, start=1):
            if len(runners) > 1:
                print(">>> 开始执行第 {} 批任务".format(i))
            self.before_runner_start(runner)
            try:
                cb = runner.run(**kwargs)
                self.on_runner_success(runner, cb)
            except Exception as e:
                self.on_runner_failed(runner, e)
            print('\n')