# -*- coding: utf-8 -*-
#
import re
import time
import uuid
import threading
import os
import time
import uuid

from collections import defaultdict
from django.db import models, transaction
from django.db.models import Q, Manager
from django.db.utils import IntegrityError
from django.utils.translation import ugettext_lazy as _
from django.utils.translation import ugettext
from django.db.transaction import atomic
from django.core.cache import cache

from common.utils.lock import DistributedLock
from common.utils.common import timeit
from common.db.models import output_as_string
from common.utils import get_logger
from orgs.mixins.models import OrgModelMixin, OrgManager
from orgs.utils import get_current_org, tmp_to_org
from orgs.models import Organization


__all__ = ['Node', 'FamilyMixin', 'compute_parent_key', 'NodeQuerySet']
logger = get_logger(__name__)


def compute_parent_key(key):
    try:
        return key[:key.rindex(':')]
    except ValueError:
        return ''


class NodeQuerySet(models.QuerySet):
    def delete(self):
        raise NotImplementedError


class FamilyMixin:
    __parents = None
    __children = None
    __all_children = None
    is_node = True
    child_mark: int

    @staticmethod
    def clean_children_keys(nodes_keys):
        sort_key = lambda k: [int(i) for i in k.split(':')]
        nodes_keys = sorted(list(nodes_keys), key=sort_key)

        nodes_keys_clean = []
        base_key = ''
        for key in nodes_keys:
            if key.startswith(base_key + ':'):
                continue
            nodes_keys_clean.append(key)
            base_key = key
        return nodes_keys_clean

    @classmethod
    def get_node_all_children_key_pattern(cls, key, with_self=True):
        pattern = r'^{0}:'.format(key)
        if with_self:
            pattern += r'|^{0}$'.format(key)
        return pattern

    @classmethod
    def get_node_children_key_pattern(cls, key, with_self=True):
        pattern = r'^{0}:[0-9]+$'.format(key)
        if with_self:
            pattern += r'|^{0}$'.format(key)
        return pattern

    def get_children_key_pattern(self, with_self=False):
        return self.get_node_children_key_pattern(self.key, with_self=with_self)

    def get_all_children_pattern(self, with_self=False):
        return self.get_node_all_children_key_pattern(self.key, with_self=with_self)

    def is_children(self, other):
        children_pattern = other.get_children_key_pattern(with_self=False)
        return re.match(children_pattern, self.key)

    def get_children(self, with_self=False):
        q = Q(parent_key=self.key)
        if with_self:
            q |= Q(key=self.key)
        return Node.objects.filter(q)

    def get_all_children(self, with_self=False):
        q = Q(key__istartswith=f'{self.key}:')
        if with_self:
            q |= Q(key=self.key)
        return Node.objects.filter(q)

    @property
    def children(self):
        return self.get_children(with_self=False)

    @property
    def all_children(self):
        return self.get_all_children(with_self=False)

    def create_child(self, value=None, _id=None):
        with atomic(savepoint=False):
            child_key = self.get_next_child_key()
            if value is None:
                value = child_key
            child = self.__class__.objects.create(
                id=_id, key=child_key, value=value
            )
            return child

    def get_or_create_child(self, value, _id=None):
        """
        :return: Node, bool (created)
        """
        children = self.get_children()
        exist = children.filter(value=value).exists()
        if exist:
            child = children.filter(value=value).first()
            created = False
        else:
            child = self.create_child(value, _id)
            created = True
        return child, created

    def get_valid_child_mark(self):
        key = "{}:{}".format(self.key, self.child_mark)
        if not self.__class__.objects.filter(key=key).exists():
            return self.child_mark
        children_keys = self.get_children().values_list('key', flat=True)
        children_keys_last = [key.split(':')[-1] for key in children_keys]
        children_keys_last = [int(k) for k in children_keys_last if k.strip().isdigit()]
        max_key_last = max(children_keys_last) if children_keys_last else 1
        return max_key_last + 1

    def get_next_child_key(self):
        child_mark = self.get_valid_child_mark()
        key = "{}:{}".format(self.key, child_mark)
        self.child_mark = child_mark + 1
        self.save()
        return key

    def get_next_child_preset_name(self):
        name = ugettext("New node")
        values = [
            child.value[child.value.rfind(' '):]
            for child in self.get_children()
            if child.value.startswith(name)
        ]
        values = [int(value) for value in values if value.strip().isdigit()]
        count = max(values) + 1 if values else 1
        return '{} {}'.format(name, count)

    # Parents
    @classmethod
    def get_node_ancestor_keys(cls, key, with_self=False):
        parent_keys = []
        key_list = key.split(":")
        if not with_self:
            key_list.pop()
        for i in range(len(key_list)):
            parent_keys.append(":".join(key_list))
            key_list.pop()
        return parent_keys

    def get_ancestor_keys(self, with_self=False):
        return self.get_node_ancestor_keys(
            self.key, with_self=with_self
        )

    @property
    def ancestors(self):
        return self.get_ancestors(with_self=False)

    def get_ancestors(self, with_self=False):
        ancestor_keys = self.get_ancestor_keys(with_self=with_self)
        return self.__class__.objects.filter(key__in=ancestor_keys)

    # @property
    # def parent_key(self):
    #     parent_key = ":".join(self.key.split(":")[:-1])
    #     return parent_key

    def compute_parent_key(self):
        return compute_parent_key(self.key)

    def is_parent(self, other):
        return other.is_children(self)

    @property
    def parent(self):
        if self.is_org_root():
            return self
        parent_key = self.parent_key
        return Node.objects.get(key=parent_key)

    @parent.setter
    def parent(self, parent):
        if not self.is_node:
            self.key = parent.key + ':fake'
            return
        children = self.get_all_children()
        old_key = self.key
        with transaction.atomic():
            self.key = parent.get_next_child_key()
            self.save()
            for child in children:
                child.key = child.key.replace(old_key, self.key, 1)
                child.save()

    def get_siblings(self, with_self=False):
        key = ':'.join(self.key.split(':')[:-1])
        pattern = r'^{}:[0-9]+$'.format(key)
        sibling = Node.objects.filter(
            key__regex=pattern.format(self.key)
        )
        if not with_self:
            sibling = sibling.exclude(key=self.key)
        return sibling

    @classmethod
    def create_node_by_full_value(cls, full_value):
        if not full_value:
            return []
        nodes_family = full_value.split('/')
        nodes_family = [v for v in nodes_family if v]
        org_root = cls.org_root()
        if nodes_family[0] == org_root.value:
            nodes_family = nodes_family[1:]
        return cls.create_nodes_recurse(nodes_family, org_root)

    @classmethod
    def create_nodes_recurse(cls, values, parent=None):
        values = [v for v in values if v]
        if not values:
            return None
        if parent is None:
            parent = cls.org_root()
        value = values[0]
        child, created = parent.get_or_create_child(value=value)
        if len(values) == 1:
            return child
        return cls.create_nodes_recurse(values[1:], child)

    def get_family(self):
        ancestors = self.get_ancestors()
        children = self.get_all_children()
        return [*tuple(ancestors), self, *tuple(children)]


class NodeAllAssetsMappingMixin:
    # Use a new plan

    # { org_id: { node_key: [ asset1_id, asset2_id ] } }
    orgid_nodekey_assetsid_mapping = defaultdict(dict)

    @classmethod
    def get_node_all_assets_id_mapping(cls, org_id):
        _mapping = cls.get_node_all_assets_id_mapping_from_memory(org_id)
        if _mapping:
            return _mapping

        _mapping = cls.get_node_all_assets_id_mapping_from_cache_or_generate_to_cache(org_id)
        cls.set_node_all_assets_id_mapping_to_memory(org_id, mapping=_mapping)
        return _mapping

    # from memory
    @classmethod
    def get_node_all_assets_id_mapping_from_memory(cls, org_id):
        mapping = cls.orgid_nodekey_assetsid_mapping.get(org_id, {})
        return mapping

    @classmethod
    def set_node_all_assets_id_mapping_to_memory(cls, org_id, mapping):
        cls.orgid_nodekey_assetsid_mapping[org_id] = mapping

    @classmethod
    def expire_node_all_assets_id_mapping_from_memory(cls, org_id):
        org_id = str(org_id)
        cls.orgid_nodekey_assetsid_mapping.pop(org_id, None)

    # get order: from memory -> (from cache -> to generate)
    @classmethod
    def get_node_all_assets_id_mapping_from_cache_or_generate_to_cache(cls, org_id):
        mapping = cls.get_node_all_assets_id_mapping_from_cache(org_id)
        if mapping:
            return mapping

        lock_key = f'KEY_LOCK_GENERATE_ORG_{org_id}_NODE_ALL_ASSETS_ID_MAPPING'
        logger.info(f'Thread[{threading.get_ident()}] acquiring lock[{lock_key}] ...')
        with DistributedLock(lock_key):
            logger.info(f'Thread[{threading.get_ident()}] acquire lock[{lock_key}] ok')
            # 这里使用无限期锁，原因是如果这里卡住了，就卡在数据库了，说明
            # 数据库繁忙，所以不应该再有线程执行这个操作，使数据库忙上加忙

            # 这里最好先判断内存中有没有，防止同一进程的多个线程重复从 cache 中获取数据，
            # 但逻辑过于繁琐，直接判断 cache 吧
            _mapping = cls.get_node_all_assets_id_mapping_from_cache(org_id)
            if _mapping:
                return _mapping

            _mapping = cls.generate_node_all_assets_id_mapping(org_id)
            cls.set_node_all_assets_id_mapping_to_cache(org_id=org_id, mapping=_mapping)
            return _mapping

    @classmethod
    def get_node_all_assets_id_mapping_from_cache(cls, org_id):
        cache_key = cls._get_cache_key_for_node_all_assets_id_mapping(org_id)
        mapping = cache.get(cache_key)
        return mapping

    @classmethod
    def set_node_all_assets_id_mapping_to_cache(cls, org_id, mapping):
        cache_key = cls._get_cache_key_for_node_all_assets_id_mapping(org_id)
        cache.set(cache_key, mapping, timeout=None)

    @classmethod
    def expire_node_all_assets_id_mapping_from_cache(cls, org_id):
        cache_key = cls._get_cache_key_for_node_all_assets_id_mapping(org_id)
        cache.delete(cache_key)

    @staticmethod
    def _get_cache_key_for_node_all_assets_id_mapping(org_id):
        return 'ASSETS_ORG_NODE_ALL_ASSETS_ID_MAPPING_{}'.format(org_id)

    @classmethod
    def generate_node_all_assets_id_mapping(cls, org_id):
        from .asset import Asset

        t1 = time.time()
        with tmp_to_org(org_id):
            nodes_id_key = Node.objects.filter(org_id=org_id) \
                .annotate(char_id=output_as_string('id')) \
                .values_list('char_id', 'key')

            # * 直接取出全部. filter(node__org_id=org_id)(大规模下会更慢)
            nodes_assets_id = Asset.nodes.through.objects.all() \
                .annotate(char_node_id=output_as_string('node_id')) \
                .annotate(char_asset_id=output_as_string('asset_id')) \
                .values_list('char_node_id', 'char_asset_id')

            node_id_ancestor_keys_mapping = {
                node_id: cls.get_node_ancestor_keys(node_key, with_self=True)
                for node_id, node_key in nodes_id_key
            }

            nodeid_assetsid_mapping = defaultdict(set)
            for node_id, asset_id in nodes_assets_id:
                nodeid_assetsid_mapping[node_id].add(asset_id)

        t2 = time.time()

        mapping = defaultdict(set)
        for node_id, node_key in nodes_id_key:
            assets_id = nodeid_assetsid_mapping[node_id]
            node_ancestor_keys = node_id_ancestor_keys_mapping[node_id]
            for ancestor_key in node_ancestor_keys:
                mapping[ancestor_key].update(assets_id)

        t3 = time.time()
        logger.debug('t1-t2(DB Query): {} s, t3-t2(Generate mapping): {} s'.format(t2-t1, t3-t2))
        return mapping


class NodeAssetsMixin(NodeAllAssetsMappingMixin):
    org_id: str
    key = ''
    id = None
    objects: Manager

    def get_all_assets(self):
        from .asset import Asset
        q = Q(nodes__key__startswith=f'{self.key}:') | Q(nodes__key=self.key)
        return Asset.objects.filter(q).distinct()

    @classmethod
    def get_node_all_assets_by_key_v2(cls, key):
        # 最初的写法是：
        #   Asset.objects.filter(Q(nodes__key__startswith=f'{node.key}:') | Q(nodes__id=node.id))
        #   可是 startswith 会导致表关联时 Asset 索引失效
        from .asset import Asset
        node_ids = cls.objects.filter(
            Q(key__startswith=f'{key}:') | Q(key=key)
        ).values_list('id', flat=True).distinct()
        assets = Asset.objects.filter(
            nodes__id__in=list(node_ids)
        ).distinct()
        return assets

    def get_assets(self):
        from .asset import Asset
        assets = Asset.objects.filter(nodes=self)
        return assets.distinct()

    def get_valid_assets(self):
        return self.get_assets().valid()

    def get_all_valid_assets(self):
        return self.get_all_assets().valid()

    @classmethod
    def get_nodes_all_assets_ids_by_keys(cls, nodes_keys):
        nodes = Node.objects.filter(key__in=nodes_keys)
        assets_ids = cls.get_nodes_all_assets(*nodes).values_list('id', flat=True)
        return assets_ids

    @classmethod
    def get_nodes_all_assets(cls, *nodes):
        from .asset import Asset
        node_ids = set()
        descendant_node_query = Q()
        for n in nodes:
            node_ids.add(n.id)
            descendant_node_query |= Q(key__istartswith=f'{n.key}:')
        if descendant_node_query:
            _ids = Node.objects.order_by().filter(descendant_node_query).values_list('id', flat=True)
            node_ids.update(_ids)
        return Asset.objects.order_by().filter(nodes__id__in=node_ids).distinct()

    def get_all_assets_id(self):
        assets_id = self.get_all_assets_id_by_node_key(org_id=self.org_id, node_key=self.key)
        return set(assets_id)

    @classmethod
    def get_all_assets_id_by_node_key(cls, org_id, node_key):
        org_id = str(org_id)
        nodekey_assetsid_mapping = cls.get_node_all_assets_id_mapping(org_id)
        assets_id = nodekey_assetsid_mapping.get(node_key, [])
        return set(assets_id)


class SomeNodesMixin:
    key = ''
    default_key = '1'
    default_value = 'Default'
    empty_key = '-11'
    empty_value = _("empty")

    @classmethod
    def default_node(cls):
        with tmp_to_org(Organization.default()):
            defaults = {'value': cls.default_value}
            try:
                obj, created = cls.objects.get_or_create(
                    defaults=defaults, key=cls.default_key,
                )
            except IntegrityError as e:
                logger.error("Create default node failed: {}".format(e))
                cls.modify_other_org_root_node_key()
                obj, created = cls.objects.get_or_create(
                    defaults=defaults, key=cls.default_key,
                )
            return obj

    def is_default_node(self):
        return self.key == self.default_key

    def is_org_root(self):
        if self.key.isdigit():
            return True
        else:
            return False

    @classmethod
    def get_next_org_root_node_key(cls):
        with tmp_to_org(Organization.root()):
            org_nodes_roots = cls.objects.filter(key__regex=r'^[0-9]+$')
            org_nodes_roots_keys = org_nodes_roots.values_list('key', flat=True)
            if not org_nodes_roots_keys:
                org_nodes_roots_keys = ['1']
            max_key = max([int(k) for k in org_nodes_roots_keys])
            key = str(max_key + 1) if max_key != 0 else '2'
            return key

    @classmethod
    def create_org_root_node(cls):
        # 如果使用current_org 在set_current_org时会死循环
        ori_org = get_current_org()
        with transaction.atomic():
            if not ori_org.is_real():
                return cls.default_node()
            key = cls.get_next_org_root_node_key()
            root = cls.objects.create(key=key, value=ori_org.name)
            return root

    @classmethod
    def org_root(cls):
        root = cls.objects.filter(parent_key='')\
            .filter(key__regex=r'^[0-9]+$')\
            .exclude(key__startswith='-')\
            .order_by('key')
        if root:
            return root[0]
        else:
            return cls.create_org_root_node()

    @classmethod
    def initial_some_nodes(cls):
        cls.default_node()

    @classmethod
    def modify_other_org_root_node_key(cls):
        """
        解决创建 default 节点失败的问题，
        因为在其他组织下存在 default 节点，故在 DEFAULT 组织下 get 不到 create 失败
        """
        logger.info("Modify other org root node key")

        with tmp_to_org(Organization.root()):
            node_key1 = cls.objects.filter(key='1').first()
            if not node_key1:
                logger.info("Not found node that `key` = 1")
                return
            if not node_key1.org.is_real():
                logger.info("Org is not real for node that `key` = 1")
                return

        with transaction.atomic():
            with tmp_to_org(node_key1.org):
                org_root_node_new_key = cls.get_next_org_root_node_key()
                for n in cls.objects.all():
                    old_key = n.key
                    key_list = n.key.split(':')
                    key_list[0] = org_root_node_new_key
                    new_key = ':'.join(key_list)
                    n.key = new_key
                    n.save()
                    logger.info('Modify key ( {} > {} )'.format(old_key, new_key))


class Node(OrgModelMixin, SomeNodesMixin, FamilyMixin, NodeAssetsMixin):
    id = models.UUIDField(default=uuid.uuid4, primary_key=True)
    key = models.CharField(unique=True, max_length=64, verbose_name=_("Key"))  # '1:1:1:1'
    value = models.CharField(max_length=128, verbose_name=_("Value"))
    full_value = models.CharField(max_length=4096, verbose_name=_('Full value'), default='')
    child_mark = models.IntegerField(default=0)
    date_create = models.DateTimeField(auto_now_add=True)
    parent_key = models.CharField(max_length=64, verbose_name=_("Parent key"),
                                  db_index=True, default='')
    assets_amount = models.IntegerField(default=0)

    objects = OrgManager.from_queryset(NodeQuerySet)()
    is_node = True
    _parents = None

    class Meta:
        verbose_name = _("Node")
        ordering = ['parent_key', 'value']

    def __str__(self):
        return self.full_value

    # def __eq__(self, other):
    #     if not other:
    #         return False
    #     return self.id == other.id
    #
    def __gt__(self, other):
        self_key = [int(k) for k in self.key.split(':')]
        other_key = [int(k) for k in other.key.split(':')]
        self_parent_key = self_key[:-1]
        other_parent_key = other_key[:-1]

        if self_parent_key and self_parent_key == other_parent_key:
            return self.value > other.value
        return self_key > other_key

    def __lt__(self, other):
        return not self.__gt__(other)

    @property
    def name(self):
        return self.value

    def computed_full_value(self):
        # 不要在列表中调用该属性
        values = self.__class__.objects.filter(
            key__in=self.get_ancestor_keys()
        ).values_list('key', 'value')
        values = [v for k, v in sorted(values, key=lambda x: len(x[0]))]
        values.append(str(self.value))
        return '/' + '/'.join(values)

    @property
    def level(self):
        return len(self.key.split(':'))

    def as_tree_node(self):
        from common.tree import TreeNode
        name = '{} ({})'.format(self.value, self.assets_amount)
        data = {
            'id': self.key,
            'name': name,
            'title': name,
            'pId': self.parent_key,
            'isParent': True,
            'open': self.is_org_root(),
            'meta': {
                'node': {
                    "id": self.id,
                    "name": self.name,
                    "value": self.value,
                    "key": self.key,
                    "assets_amount": self.assets_amount,
                },
                'type': 'node'
            }
        }
        tree_node = TreeNode(**data)
        return tree_node

    def has_children_or_has_assets(self):
        if self.children or self.get_assets().exists():
            return True
        return False

    def delete(self, using=None, keep_parents=False):
        if self.has_children_or_has_assets():
            return
        return super().delete(using=using, keep_parents=keep_parents)

    def update_child_full_value(self):
        nodes = self.get_all_children(with_self=True)
        sort_key_func = lambda n: [int(i) for i in n.key.split(':')]
        nodes_sorted = sorted(list(nodes), key=sort_key_func)
        nodes_mapper = {n.key: n for n in nodes_sorted}
        if not self.is_org_root():
            # 如果是org_root，那么parent_key为'', parent为自己，所以这种情况不处理
            # 更新自己时，自己的parent_key获取不到
            nodes_mapper.update({self.parent_key: self.parent})
        for node in nodes_sorted:
            parent = nodes_mapper.get(node.parent_key)
            if not parent:
                if node.parent_key:
                    logger.error(f'Node parent node in mapper: {node.parent_key} {node.value}')
                continue
            node.full_value = parent.full_value + '/' + node.value
        self.__class__.objects.bulk_update(nodes, ['full_value'])

    def save(self, *args, **kwargs):
        self.full_value = self.computed_full_value()
        instance = super().save(*args, **kwargs)
        self.update_child_full_value()
        return instance