"""Copyright since 2019, EPAM Systems

   This file is part of OSCI.

   OSCI 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.

   OSCI 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 OSCI.  If not, see <http://www.gnu.org/licenses/>."""

from datetime import datetime, timedelta

from .osci_change_report import get_osci_ranking_change_report
from osci.datalake.reports.general.change_ranking import OSCIChangeRanking, OSCIGrowthSpeed
from osci.datalake.reports.general import OSCIChangeRankingDTD
from osci.datalake.reports.general.osci_ranking import OSCIRankingYTD
from osci.datalake.reports.excel import OSCIChangeRankingExcel


def get_previous_date(date: datetime):
    if date.month == 1:
        return datetime(year=date.year, month=date.month, day=1)
    return datetime(year=date.year, month=date.month, day=1) - timedelta(days=1)


def get_prev_day(date: datetime):
    """Get previous day from the date except 1st January"""
    if date.month == 1 and date.day == 1:
        return date
    return date - timedelta(days=1)


def get_change_report(date: datetime):
    previous_date = get_previous_date(date=date)

    ranking = OSCIRankingYTD(date=date)
    ranking_df = ranking.read().reset_index().rename(columns={'index': ranking.schema.position})

    old_ranking = OSCIRankingYTD(date=previous_date)
    old_ranking_df = old_ranking.read().reset_index().rename(columns={'index': old_ranking.schema.position})

    report = OSCIChangeRanking(date=date)
    change_report = get_osci_ranking_change_report(old_report=old_ranking_df,
                                                   new_report=ranking_df,

                                                   company_field=ranking.schema.company,

                                                   active_contributors_field=ranking.schema.active,
                                                   active_contributors_change_field=report.schema.active_change,

                                                   total_community_field=ranking.schema.total,
                                                   total_community_change_field=report.schema.total_change,

                                                   rank_field=ranking.schema.position,
                                                   rank_change_field=report.schema.position_change)

    report.save(df=change_report)

    excel_report = OSCIChangeRankingExcel(from_date=previous_date, to_date=date)
    excel_report.save(df=change_report)


def get_daily_ranking_change(date: datetime):
    """Get daily Active Contributors and Total Community changes"""
    prev_date = get_prev_day(date)
    prev_ranking = OSCIRankingYTD(date=prev_date)
    prev_ranking_df = prev_ranking.read().reset_index().rename(columns={'index': prev_ranking.schema.position})

    ranking = OSCIRankingYTD(date=date)
    ranking_df = ranking.read().reset_index().rename(columns={'index': ranking.schema.position})

    report = OSCIChangeRankingDTD(date=date)
    change_report = get_osci_ranking_change_report(
        old_report=prev_ranking_df,
        new_report=ranking_df,
        company_field=ranking.schema.company,

        active_contributors_field=ranking.schema.active,
        active_contributors_change_field=report.schema.active_change,

        total_community_field=ranking.schema.total,
        total_community_change_field=report.schema.total_change,

        rank_field=ranking.schema.position,
        rank_change_field=report.schema.position_change)

    report.save(df=change_report)
    return change_report


def generate_growth_speed_report(date: datetime):
    """Generate growth speed report"""
    previous_date = get_prev_day(date)

    ranking = OSCIChangeRanking(date=date)
    ranking_df = ranking.read().reset_index()

    old_ranking = OSCIChangeRanking(date=previous_date)
    old_ranking_df = old_ranking.read()

    report = OSCIGrowthSpeed(date=date)
    change_report = get_osci_ranking_change_report(old_report=old_ranking_df,
                                                   new_report=ranking_df,

                                                   company_field=ranking.schema.company,

                                                   active_contributors_field=ranking.schema.active_change,
                                                   active_contributors_change_field=report.schema.active_growth,

                                                   total_community_field=ranking.schema.total_change,
                                                   total_community_change_field=report.schema.total_growth,

                                                   rank_field=ranking.schema.position_change,
                                                   rank_change_field=report.schema.position_growth)

    report.save(df=change_report)