import datetime
from flask import request, abort, redirect, url_for, flash, render_template
import paginate
import sqlalchemy as sa
import wradmin.model as model
import wrpylib.wrmwcache


class BerichtController:

    def _dependent_date_dict(self, date_invalid):
        now = datetime.datetime.today()
        if date_invalid is None:
            date_invalid = now
        return {
            'date_now': now,
            'date_no_change': date_invalid,
            'date_tomorrow': now + datetime.timedelta(1),
            'date_one_week': now + datetime.timedelta(7),
            'date_two_weeks': now + datetime.timedelta(14),
            'date_one_week_more': date_invalid + datetime.timedelta(7),
            'date_end_of_saison': datetime.datetime(now.year if now.month < 7 else now.year + 1, 7, 1),
        }

    def list(self):
        """Lists all reports"""
        q = model.meta.Session.query(model.WrReport)
        q = q.order_by(sa.sql.expression.desc(model.WrReport.id))
        paginator = paginate.Page(q.all(), page=int(request.args.get('page', 1)),
                                  url_maker=lambda page: url_for('bericht_list', page=page),
                                  items_per_page=25)
        return render_template('bericht_list.html', paginator=paginator)

    def view(self, id):
        """Displays a report"""
        q = model.meta.Session.query(model.WrReport)
        wrreport = q.get(id)
        if wrreport is None:
            abort(404)
        dates = self._dependent_date_dict(wrreport.date_invalid)
        return render_template('bericht_view.html', wrreport=wrreport, **dates)

    def change_date_invalid(self, id=None):
        assert request.method == 'POST'
        if id is None:
            abort(404)
        wrreport_q = model.meta.Session.query(model.WrReport)
        wrreport = wrreport_q.get(id)
        if wrreport is None:
            abort(404)
        dates = self._dependent_date_dict(wrreport.date_invalid)
        date = request.form['date_invalid']
        if   date == 'tomorrow':      wrreport.date_invalid = dates['date_tomorrow']
        elif date == 'one_week':      wrreport.date_invalid = dates['date_one_week']
        elif date == 'two_weeks':     wrreport.date_invalid = dates['date_two_weeks']
        elif date == 'one_week_more': wrreport.date_invalid = dates['date_one_week_more']
        elif date == 'end_of_saison': wrreport.date_invalid = dates['date_end_of_saison']
        elif date == 'now':           wrreport.date_invalid = dates['date_now']
        elif date == 'userdefined':
            date_userdefined = request.form['date_userdefined']
            try:
                date_userdefined = datetime.datetime.strptime(date_userdefined, '%Y-%m-%d %H:%M')
            except ValueError as e:
                flash(str(e))
                return redirect(url_for('bericht_view', id=id))
            wrreport.date_invalid = date_userdefined
        model.meta.Session.commit()
        flash('Datum wurde erfolgreich geändert')
        return redirect(url_for('bericht_view', id=id))

    def update_reportcache(self):
        """Updates the wrreportcache table."""
        c = model.meta.Session.connection()
        try:
            wrpylib.wrmwcache.update_wrreportcache(c)
            model.meta.Session.commit()
            flash('Die Berichtzusammenfassung-Tabelle wurde erfolgreich aktualisiesrt.', 'info')
        except wrpylib.wrmwcache.UpdateCacheError as e:
            flash(str(e), 'error')
        # Redirect to result page
        return redirect(url_for('bericht_list'))