/*
 * Copyright 2010-2011 Ning, Inc.
 *
 * Ning licenses this file to you under the Apache License, version 2.0
 * (the "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at:
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package com.ning.billing.invoice.tests.inAdvance;

import com.ning.billing.invoice.model.InvalidDateSequenceException;
import org.joda.time.DateTime;
import org.testng.annotations.Test;

import java.math.BigDecimal;

@Test(groups = {"fast", "invoicing", "proRation"})
public abstract class GenericProRationTestBase extends ProRationInAdvanceTestBase {
    /**
     * used for testing cancellation in less than a single billing period
     * @return BigDecimal the number of days in the billing period beginning 2011/1/1
     */
    protected abstract BigDecimal getDaysInTestPeriod();
    
    @Test
    public void testSinglePlan_OnStartDate() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);

        testCalculateNumberOfBillingCycles(startDate, startDate, 15, ONE);
    }

    @Test
    public void testSinglePlan_LessThanOnePeriod() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);
        DateTime targetDate = buildDateTime(2011, 3, 1);

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, ONE);
    }

    @Test
    public void testSinglePlan_OnePeriodLessADayAfterStart() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);
        DateTime targetDate = startDate.plusMonths(getBillingPeriod().getNumberOfMonths()).plusDays(-1);

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, ONE);
    }

    @Test
    public void testSinglePlan_ExactlyOnePeriodAfterStart() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);
        DateTime targetDate = startDate.plusMonths(getBillingPeriod().getNumberOfMonths());

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, TWO);
    }

    @Test
    public void testSinglePlan_SlightlyMoreThanOnePeriodAfterStart() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);
        DateTime targetDate = startDate.plusMonths(getBillingPeriod().getNumberOfMonths()).plusDays(1);

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, TWO);
    }

    @Test
    public void testSinglePlan_CrossingYearBoundary() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 12, 15);
        DateTime oneCycleLater = startDate.plusMonths(getBillingPeriod().getNumberOfMonths());

        // test just before the billing cycle day
        testCalculateNumberOfBillingCycles(startDate, oneCycleLater.plusDays(-1), 15, ONE);

        // test on the billing cycle day
        testCalculateNumberOfBillingCycles(startDate, oneCycleLater, 15, TWO);

        // test just after the billing cycle day
        testCalculateNumberOfBillingCycles(startDate, oneCycleLater.plusDays(1), 15, TWO);
    }

    @Test
    public void testSinglePlan_StartingMidFebruary() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 2, 15);
        DateTime targetDate = startDate.plusMonths(getBillingPeriod().getNumberOfMonths());

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, TWO);
    }

    @Test
    public void testSinglePlan_StartingMidFebruaryOfLeapYear() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2012, 2, 15);
        DateTime targetDate = startDate.plusMonths(getBillingPeriod().getNumberOfMonths());

        testCalculateNumberOfBillingCycles(startDate, targetDate, 15, TWO);
    }

    @Test
    public void testSinglePlan_MovingForwardThroughTime() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 31);
        BigDecimal expectedValue = ONE;

        for (int i = 1; i <= 12; i++) {
            DateTime oneCycleLater = startDate.plusMonths(i * getBillingPeriod().getNumberOfMonths());
            // test just before the billing cycle day
            testCalculateNumberOfBillingCycles(startDate, oneCycleLater.plusDays(-1), 31, expectedValue);

            expectedValue = expectedValue.add(ONE);

            // test on the billing cycle day
            testCalculateNumberOfBillingCycles(startDate, oneCycleLater, 31, expectedValue);

            // test just after the billing cycle day
            testCalculateNumberOfBillingCycles(startDate, oneCycleLater.plusDays(1), 31, expectedValue);
        }
    }
    
    // tests for cancellation in less than one period, beginning Jan 1
    @Test
    public void testCancelledBeforeOnePeriod_TargetDateInStartDate() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 1, 1);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }

    @Test
    public void testCancelledBeforeOnePeriod_TargetDateInSubscriptionPeriod() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 1, 7);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }

    @Test
    public void testCancelledBeforeOnePeriod_TargetDateOnEndDate() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 1, 15);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }

    @Test
    public void testCancelledBeforeOnePeriod_TargetDateAfterEndDateButInFirstBillingPeriod() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 1, 17);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }

    @Test
    public void testCancelledBeforeOnePeriod_TargetDateAtEndOfFirstBillingPeriod() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 2, 1);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }

    @Test
    public void testCancelledBeforeOnePeriod_TargetDateAfterFirstBillingPeriod() throws InvalidDateSequenceException {
        DateTime startDate = buildDateTime(2011, 1, 1);
        DateTime targetDate = buildDateTime(2011, 4, 5);
        DateTime endDate = buildDateTime(2011, 1, 15);

        BigDecimal expectedValue = FOURTEEN.divide(getDaysInTestPeriod(), NUMBER_OF_DECIMALS, ROUNDING_METHOD);
        testCalculateNumberOfBillingCycles(startDate, endDate, targetDate, 1, expectedValue);
    }
}
