# -*- coding: utf-8 -*-
#
# This file is part of SENAITE.CORE.
#
# SENAITE.CORE is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation, version 2.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Copyright 2018-2021 by it's authors.
# Some rights reserved, see README and LICENSE.

import re

import six

from AccessControl import ClassSecurityInfo
from bika.lims import api
from bika.lims.browser.widgets import RemarksWidget
from bika.lims.events import RemarksAddedEvent
from bika.lims.interfaces import IRemarksField
from bika.lims.utils import tmpID
from DateTime import DateTime
from Products.Archetypes.event import ObjectEditedEvent
from Products.Archetypes.Field import ObjectField
from Products.Archetypes.Registry import registerField
from Products.CMFPlone.i18nl10n import ulocalized_time
from zope import event
from zope.interface import implements


class RemarksHistory(list):
    """A list containing a remarks history, but __str__ returns the legacy
    format from instances prior v1.3.3
    """

    def html(self):
        return api.text_to_html(str(self))

    def __str__(self):
        """Returns the remarks in legacy format
        """
        remarks = map(lambda rec: str(rec), self)
        remarks = filter(None, remarks)
        return "\n".join(remarks)

    def __eq__(self, y):
        if isinstance(y, six.string_types):
            return str(self) == y
        return super(RemarksHistory, self).__eq__(y)


class RemarksHistoryRecord(dict):
    """A dict implementation that represents a record/entry of Remarks History
    """

    def __init__(self, *arg, **kw):
        super(RemarksHistoryRecord, self).__init__(*arg, **kw)
        self["id"] = self.id or tmpID()
        self["user_id"] = self.user_id
        self["user_name"] = self.user_name
        self["created"] = self.created or DateTime().ISO()
        self["content"] = self.content

    @property
    def id(self):
        return self.get("id", "")

    @property
    def user_id(self):
        return self.get("user_id", "")

    @property
    def user_name(self):
        return self.get("user_name", "")

    @property
    def created(self):
        return self.get("created", "")

    @property
    def created_ulocalized(self):
        return ulocalized_time(self.created,
                               long_format=True,
                               context=api.get_portal(),
                               request=api.get_request(),
                               domain="senaite.core")

    @property
    def content(self):
        return self.get("content", "")

    @property
    def html_content(self):
        return api.text_to_html(self.content)

    def __str__(self):
        """Returns a legacy string format of the Remarks record
        """
        if not self.content:
            return ""
        if self.created and self.user_id:
            # Build the legacy format
            return "=== {} ({})\n{}".format(self.created, self.user_id,
                                            self.content)
        return self.content


class RemarksField(ObjectField):
    """A field that stores remarks.  The value submitted to the setter
    will always be appended to the actual value of the field.
    A divider will be included with extra information about the text.
    """

    _properties = ObjectField._properties.copy()
    _properties.update({
        'type': 'remarks',
        'widget': RemarksWidget,
        'default': '',
    })

    implements(IRemarksField)
    security = ClassSecurityInfo()

    @property
    def searchable(self):
        """Returns False, preventing this field to be searchable by AT's
        SearcheableText
        """
        return False

    @security.private
    def set(self, instance, value, **kwargs):
        """Adds the value to the existing text stored in the field,
        along with a small divider showing username and date of this entry.
        """

        if not value:
            return

        if isinstance(value, RemarksHistory):
            # Override the whole history here
            history = value

        elif isinstance(value, (list, tuple)):
            # This is a list, convert to RemarksHistory
            remarks = map(lambda item: RemarksHistoryRecord(item), value)
            history = RemarksHistory(remarks)

        elif isinstance(value, RemarksHistoryRecord):
            # This is a record, append to the history
            history = self.get_history(instance)
            history.insert(0, value)

        elif isinstance(value, six.string_types):
            # Create a new history record
            record = self.to_history_record(value)

            # Append the new record to the history
            history = self.get_history(instance)
            history.insert(0, record)

        else:
            raise ValueError("Type not supported: {}".format(type(value)))

        # Store the data
        ObjectField.set(self, instance, history)

        # N.B. ensure updated catalog metadata for the snapshot
        instance.reindexObject()

        # notify object edited event
        event.notify(ObjectEditedEvent(instance))

        # notify new remarks for e.g. later email notification etc.
        event.notify(RemarksAddedEvent(instance, history))

    def get(self, instance, **kwargs):
        """Returns a RemarksHistory object
        """
        return self.get_history(instance)

    def getRaw(self, instance, **kwargs):
        """Returns raw field value (possible wrapped in BaseUnit)
        """
        value = ObjectField.get(self, instance, **kwargs)
        # getattr(instance, "Remarks") returns a BaseUnit
        if callable(value):
            value = value()
        return value

    def to_history_record(self, value):
        """Transforms the value to an history record
        """
        user = api.get_current_user()
        contact = api.get_user_contact(user)
        fullname = contact and contact.getFullname() or ""
        if not contact:
            # get the fullname from the user properties
            props = api.get_user_properties(user)
            fullname = props.get("fullname", "")
        return RemarksHistoryRecord(user_id=user.id,
                                    user_name=fullname,
                                    content=value.strip())

    def get_history(self, instance):
        """Returns a RemarksHistory object with the remarks entries
        """
        remarks = instance.getRawRemarks()
        if not remarks:
            return RemarksHistory()

        # Backwards compatibility with legacy from < v1.3.3
        if isinstance(remarks, six.string_types):
            parsed_remarks = self._parse_legacy_remarks(remarks)
            if parsed_remarks is None:
                remark = RemarksHistoryRecord(content=remarks.strip())
                remarks = RemarksHistory([remark, ])
            else:
                remarks = RemarksHistory(
                    map(lambda r: RemarksHistoryRecord(r), parsed_remarks))

        return remarks

    def _parse_legacy_remarks(self, text):
        """Parse legacy remarks from the text
        """

        # split legacy remarks on the complete delimiter, e.g.:
        # === Tue, 28 Jan 2020 06:53:58 +0100 (admin)\nThis is a Test
        lines = re.split(r"(===) ([A-Za-z]{3}, \d{1,2} [A-Za-z]{3} \d{2,4} \d{2}:\d{2}:\d{2} [+-]{1}\d{4}) \((.*?)\)", text)  # noqa

        record = None
        records = []

        # group into remark records of date, user-id and content
        for line in lines:
            # start a new remarks record when the marker was found
            if line == "===":
                record = []
                # immediately append the new entry to the records
                records.append(record)
                # skip the marker entry
                continue

            # append the line to the entry until the next marker is found
            # -> this also skips the empty first line
            if record is not None:
                record.append(line)

        remarks = []

        for record in records:
            # each record must contain the date, user-id and text
            # -> we invalidate the whole parsing if this is not given
            if len(record) != 3:
                return None

            created, userid, content = record

            # try to get the full name of the user id
            fullname = self._get_fullname_from_user_id(userid)

            # strip off leading and trailing escape sequences from the content
            content = content.strip("\n\r\t")

            # append a remarks record
            remarks.append({
               "created": created,
               "user_id": userid,
               "user_name": fullname,
               "content": content,
            })

        return remarks

    def _get_fullname_from_user_id(self, userid, default=""):
        """Try the fullname of the user
        """
        fullname = default
        user = api.get_user(userid)
        if user:
            props = api.get_user_properties(user)
            fullname = props.get("fullname", fullname)
            contact = api.get_user_contact(user)
            fullname = contact and contact.getFullname() or fullname
        return fullname


registerField(RemarksField, title="Remarks", description="")
