# SPDX-License-Identifier: GPL-3.0-or-later

# Haketilo proxy data and configuration (RepoRef and RepoStore subtypes).
#
# This file is part of Hydrilla&Haketilo.
#
# Copyright (C) 2022 Wojtek Kosior
#
# This program 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, either version 3 of the License, or
# (at your option) any later version.
#
# 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, see <https://www.gnu.org/licenses/>.
#
#
# I, Wojtek Kosior, thereby promise not to sue for violation of this
# file's license. Although I request that you do not make use this code
# in a proprietary program, I am not going to enforce this in court.

"""
This module provides an interface to interact with repositories configured
inside Haketilo.
"""

# Enable using with Python 3.7.
from __future__ import annotations

import typing as t
import dataclasses as dc

from datetime import datetime

from .. import state as st
from . import base

def make_repo_display_info(
        ref:            st.RepoRef,
        name:           str,
        url:            t.Optional[str],
        deleted:        t.Optional[bool],
        last_refreshed: t.Optional[int],
        resource_count: int,
        mapping_count:  int
) -> st.RepoDisplayInfo:
        last_refreshed_converted: t.Optional[datetime] = None
        if last_refreshed is not None:
            last_refreshed_converted = datetime.fromtimestamp(last_refreshed)

        return st.RepoDisplayInfo(
            ref            = ref,
            name           = name,
            url            = url,
            deleted        = deleted,
            last_refreshed = last_refreshed_converted,
            resource_count = resource_count,
            mapping_count  = mapping_count
        )


@dc.dataclass(frozen=True, unsafe_hash=True)
class ConcreteRepoRef(st.RepoRef):
    """...."""
    state: base.HaketiloStateWithFields = dc.field(hash=False, compare=False)

    def remove(self) -> None:
        raise NotImplementedError()

    def update(
            self,
            *,
            name: t.Optional[str] = None,
            url:  t.Optional[str] = None
    ) -> st.RepoRef:
        raise NotImplementedError()

    def refresh(self) -> st.RepoIterationRef:
        raise NotImplementedError()

    def get_display_info(self) -> st.RepoDisplayInfo:
        with self.state.cursor() as cursor:
            cursor.execute(
                '''
                SELECT
                        name, url, deleted, last_refreshed,
                        resource_count, mapping_count
                FROM
                        repo_display_infos
                WHERE
                        repo_id = ?;
                ''',
                (self.id,)
            )

            rows = cursor.fetchall()

        if rows == []:
            raise st.MissingItemError()

        row, = rows

        return make_repo_display_info(self, *row)


@dc.dataclass(frozen=True)
class ConcreteRepoStore(st.RepoStore):
    state: base.HaketiloStateWithFields

    def get(self, id: str) -> st.RepoRef:
        return ConcreteRepoRef(id, self.state)

    def get_display_infos(self, include_deleted: bool = False) \
        -> t.Iterable[st.RepoDisplayInfo]:
        with self.state.cursor() as cursor:
            condition: str = 'TRUE'
            if include_deleted:
                condition = 'COALESCE(deleted = FALSE, TRUE)'

            cursor.execute(
                f'''
                SELECT
                        repo_id, name, url, deleted, last_refreshed,
                        resource_count, mapping_count
                FROM
                        repo_display_infos
                WHERE
                        {condition}
                ORDER BY
                        repo_id != 1, name;
                '''
            )

            all_rows = cursor.fetchall()

        assert len(all_rows) > 0 and all_rows[0][0] == 1

        result = []
        for row in all_rows:
            repo_id, *rest = row

            ref = ConcreteRepoRef(str(repo_id), self.state)

            result.append(make_repo_display_info(ref, *rest))

        return result