import React from 'react';
import PropTypes from 'prop-types';
import momentPropTypes from 'react-moment-proptypes';
import { forbidExtraProps, nonNegativeInteger } from 'airbnb-prop-types';
import moment from 'moment';
import values from 'object.values';
import isTouchDevice from 'is-touch-device';

import { DayPickerPhrases } from '../defaultPhrases';
import getPhrasePropTypes from '../utils/getPhrasePropTypes';

import isInclusivelyAfterDay from '../utils/isInclusivelyAfterDay';
import isNextDay from '../utils/isNextDay';
import isSameDay from '../utils/isSameDay';
import isAfterDay from '../utils/isAfterDay';
import isBeforeDay from '../utils/isBeforeDay';

import getVisibleDays from '../utils/getVisibleDays';
import isDayVisible from '../utils/isDayVisible';

import toISODateString from '../utils/toISODateString';
import toISOMonthString from '../utils/toISOMonthString';

import FocusedInputShape from '../shapes/FocusedInputShape';
import ScrollableOrientationShape from '../shapes/ScrollableOrientationShape';
import DayOfWeekShape from '../shapes/DayOfWeekShape';

import {
  START_DATE,
  END_DATE,
  HORIZONTAL_ORIENTATION,
  VERTICAL_SCROLLABLE,
  DAY_SIZE,
} from '../constants';

import DayPicker from './DayPicker';

const propTypes = forbidExtraProps({
  startDate: momentPropTypes.momentObj,
  endDate: momentPropTypes.momentObj,
  onDatesChange: PropTypes.func,

  focusedInput: FocusedInputShape,
  onFocusChange: PropTypes.func,
  onClose: PropTypes.func,

  keepOpenOnDateSelect: PropTypes.bool,
  minimumNights: PropTypes.number,
  isOutsideRange: PropTypes.func,
  isDayBlocked: PropTypes.func,
  isDayHighlighted: PropTypes.func,

  // DayPicker props
  renderMonth: PropTypes.func,
  enableOutsideDays: PropTypes.bool,
  numberOfMonths: PropTypes.number,
  orientation: ScrollableOrientationShape,
  withPortal: PropTypes.bool,
  initialVisibleMonth: PropTypes.func,
  hideKeyboardShortcutsPanel: PropTypes.bool,
  daySize: nonNegativeInteger,
  noBorder: PropTypes.bool,

  navPrev: PropTypes.node,
  navNext: PropTypes.node,

  onPrevMonthClick: PropTypes.func,
  onNextMonthClick: PropTypes.func,
  onOutsideClick: PropTypes.func,
  renderCalendarDay: PropTypes.func,
  renderDayContents: PropTypes.func,
  renderCalendarInfo: PropTypes.func,
  firstDayOfWeek: DayOfWeekShape,
  verticalHeight: nonNegativeInteger,
  transitionDuration: nonNegativeInteger,

  // accessibility
  onBlur: PropTypes.func,
  isFocused: PropTypes.bool,
  showKeyboardShortcuts: PropTypes.bool,

  // i18n
  monthFormat: PropTypes.string,
  weekDayFormat: PropTypes.string,
  phrases: PropTypes.shape(getPhrasePropTypes(DayPickerPhrases)),
  dayAriaLabelFormat: PropTypes.string,

  isRTL: PropTypes.bool,
});

const defaultProps = {
  startDate: undefined, // TODO: use null
  endDate: undefined, // TODO: use null
  onDatesChange() {},

  focusedInput: null,
  onFocusChange() {},
  onClose() {},

  keepOpenOnDateSelect: false,
  minimumNights: 1,
  isOutsideRange() {},
  isDayBlocked() {},
  isDayHighlighted() {},

  // DayPicker props
  renderMonth: null,
  enableOutsideDays: false,
  numberOfMonths: 1,
  orientation: HORIZONTAL_ORIENTATION,
  withPortal: false,
  hideKeyboardShortcutsPanel: false,
  initialVisibleMonth: null,
  daySize: DAY_SIZE,

  navPrev: null,
  navNext: null,

  onPrevMonthClick() {},
  onNextMonthClick() {},
  onOutsideClick() {},

  renderCalendarDay: undefined,
  renderDayContents: null,
  renderCalendarInfo: null,
  firstDayOfWeek: null,
  verticalHeight: null,
  noBorder: false,
  transitionDuration: undefined,

  // accessibility
  onBlur() {},
  isFocused: false,
  showKeyboardShortcuts: false,

  // i18n
  monthFormat: 'MMMM YYYY',
  weekDayFormat: 'dd',
  phrases: DayPickerPhrases,

  isRTL: false,
};

const getChooseAvailableDatePhrase = (phrases, focusedInput) => {
  if (focusedInput === START_DATE) {
    return phrases.chooseAvailableStartDate;
  } else if (focusedInput === END_DATE) {
    return phrases.chooseAvailableEndDate;
  }
  return phrases.chooseAvailableDate;
};

export default class DayPickerRangeController extends React.Component {
  constructor(props) {
    super(props);

    this.isTouchDevice = isTouchDevice();
    this.today = moment();
    this.modifiers = {
      today: day => this.isToday(day),
      blocked: day => this.isBlocked(day),
      'blocked-calendar': day => props.isDayBlocked(day),
      'blocked-out-of-range': day => props.isOutsideRange(day),
      'highlighted-calendar': day => props.isDayHighlighted(day),
      valid: day => !this.isBlocked(day),
      'selected-start': day => this.isStartDate(day),
      'selected-end': day => this.isEndDate(day),
      'blocked-minimum-nights': day => this.doesNotMeetMinimumNights(day),
      'selected-span': day => this.isInSelectedSpan(day),
      'last-in-range': day => this.isLastInRange(day),
      hovered: day => this.isHovered(day),
      'hovered-span': day => this.isInHoveredSpan(day),
      'after-hovered-start': day => this.isDayAfterHoveredStartDate(day),
    };

    const { currentMonth, visibleDays } = this.getStateForNewMonth(props);

    // initialize phrases
    // set the appropriate CalendarDay phrase based on focusedInput
    const chooseAvailableDate = getChooseAvailableDatePhrase(props.phrases, props.focusedInput);

    this.state = {
      hoverDate: null,
      currentMonth,
      phrases: {
        ...props.phrases,
        chooseAvailableDate,
      },
      visibleDays,
    };

    this.onDayClick = this.onDayClick.bind(this);
    this.onDayMouseEnter = this.onDayMouseEnter.bind(this);
    this.onDayMouseLeave = this.onDayMouseLeave.bind(this);
    this.onPrevMonthClick = this.onPrevMonthClick.bind(this);
    this.onNextMonthClick = this.onNextMonthClick.bind(this);
    this.onMultiplyScrollableMonths = this.onMultiplyScrollableMonths.bind(this);
    this.getFirstFocusableDay = this.getFirstFocusableDay.bind(this);
    this.setDayPickerRef = this.setDayPickerRef.bind(this);
  }

  componentWillReceiveProps(nextProps) {
    const {
      startDate,
      endDate,
      focusedInput,
      minimumNights,
      isOutsideRange,
      isDayBlocked,
      isDayHighlighted,
      phrases,
      initialVisibleMonth,
      numberOfMonths,
      enableOutsideDays,
    } = nextProps;

    const {
      startDate: prevStartDate,
      endDate: prevEndDate,
      focusedInput: prevFocusedInput,
      minimumNights: prevMinimumNights,
      isOutsideRange: prevIsOutsideRange,
      isDayBlocked: prevIsDayBlocked,
      isDayHighlighted: prevIsDayHighlighted,
      phrases: prevPhrases,
      initialVisibleMonth: prevInitialVisibleMonth,
      numberOfMonths: prevNumberOfMonths,
      enableOutsideDays: prevEnableOutsideDays,
    } = this.props;

    let { visibleDays } = this.state;

    let recomputeOutsideRange = false;
    let recomputeDayBlocked = false;
    let recomputeDayHighlighted = false;

    if (isOutsideRange !== prevIsOutsideRange) {
      this.modifiers['blocked-out-of-range'] = day => isOutsideRange(day);
      recomputeOutsideRange = true;
    }

    if (isDayBlocked !== prevIsDayBlocked) {
      this.modifiers['blocked-calendar'] = day => isDayBlocked(day);
      recomputeDayBlocked = true;
    }

    if (isDayHighlighted !== prevIsDayHighlighted) {
      this.modifiers['highlighted-calendar'] = day => isDayHighlighted(day);
      recomputeDayHighlighted = true;
    }

    const recomputePropModifiers = (
      recomputeOutsideRange || recomputeDayBlocked || recomputeDayHighlighted
    );

    const didStartDateChange = startDate !== prevStartDate;
    const didEndDateChange = endDate !== prevEndDate;
    const didFocusChange = focusedInput !== prevFocusedInput;

    if (
      numberOfMonths !== prevNumberOfMonths ||
      enableOutsideDays !== prevEnableOutsideDays ||
      (
        initialVisibleMonth !== prevInitialVisibleMonth &&
        !prevFocusedInput &&
        didFocusChange
      )
    ) {
      const newMonthState = this.getStateForNewMonth(nextProps);
      const { currentMonth } = newMonthState;
      ({ visibleDays } = newMonthState);
      this.setState({
        currentMonth,
        visibleDays,
      });
    }

    let modifiers = {};

    if (didStartDateChange) {
      modifiers = this.deleteModifier(modifiers, prevStartDate, 'selected-start');
      modifiers = this.addModifier(modifiers, startDate, 'selected-start');

      if (prevStartDate) {
        const startSpan = prevStartDate.clone().add(1, 'day');
        const endSpan = prevStartDate.clone().add(prevMinimumNights + 1, 'days');
        modifiers = this.deleteModifierFromRange(modifiers, startSpan, endSpan, 'after-hovered-start');
      }
    }

    if (didEndDateChange) {
      modifiers = this.deleteModifier(modifiers, prevEndDate, 'selected-end');
      modifiers = this.addModifier(modifiers, endDate, 'selected-end');
    }

    if (didStartDateChange || didEndDateChange) {
      if (prevStartDate && prevEndDate) {
        modifiers = this.deleteModifierFromRange(
          modifiers,
          prevStartDate,
          prevEndDate.clone().add(1, 'day'),
          'selected-span',
        );
      }

      if (startDate && endDate) {
        modifiers = this.deleteModifierFromRange(
          modifiers,
          startDate,
          endDate.clone().add(1, 'day'),
          'hovered-span',
        );

        modifiers = this.addModifierToRange(
          modifiers,
          startDate.clone().add(1, 'day'),
          endDate,
          'selected-span',
        );
      }
    }

    if (!this.isTouchDevice && didStartDateChange && startDate && !endDate) {
      const startSpan = startDate.clone().add(1, 'day');
      const endSpan = startDate.clone().add(minimumNights + 1, 'days');
      modifiers = this.addModifierToRange(modifiers, startSpan, endSpan, 'after-hovered-start');
    }

    if (minimumNights > 0 || minimumNights !== prevMinimumNights) {
      if (didFocusChange || didStartDateChange) {
        const startSpan = prevStartDate || this.today;
        modifiers = this.deleteModifierFromRange(
          modifiers,
          startSpan,
          startSpan.clone().add(minimumNights, 'days'),
          'blocked-minimum-nights',
        );
      }

      if (startDate && focusedInput === END_DATE) {
        modifiers = this.addModifierToRange(
          modifiers,
          startDate,
          startDate.clone().add(minimumNights, 'days'),
          'blocked-minimum-nights',
        );
      }
    }

    if (didFocusChange || recomputePropModifiers) {
      values(visibleDays).forEach((days) => {
        Object.keys(days).forEach((day) => {
          const momentObj = moment(day);

          if (this.isBlocked(momentObj)) {
            modifiers = this.addModifier(modifiers, momentObj, 'blocked');
          } else {
            modifiers = this.deleteModifier(modifiers, momentObj, 'blocked');
          }

          if (didFocusChange || recomputeOutsideRange) {
            if (isOutsideRange(momentObj)) {
              modifiers = this.addModifier(modifiers, momentObj, 'blocked-out-of-range');
            } else {
              modifiers = this.deleteModifier(modifiers, momentObj, 'blocked-out-of-range');
            }
          }

          if (didFocusChange || recomputeDayBlocked) {
            if (isDayBlocked(momentObj)) {
              modifiers = this.addModifier(modifiers, momentObj, 'blocked-calendar');
            } else {
              modifiers = this.deleteModifier(modifiers, momentObj, 'blocked-calendar');
            }
          }

          if (didFocusChange || recomputeDayHighlighted) {
            if (isDayHighlighted(momentObj)) {
              modifiers = this.addModifier(modifiers, momentObj, 'highlighted-calendar');
            } else {
              modifiers = this.deleteModifier(modifiers, momentObj, 'highlighted-calendar');
            }
          }
        });
      });
    }

    const today = moment();
    if (!isSameDay(this.today, today)) {
      modifiers = this.deleteModifier(modifiers, this.today, 'today');
      modifiers = this.addModifier(modifiers, today, 'today');
      this.today = today;
    }

    if (Object.keys(modifiers).length > 0) {
      this.setState({
        visibleDays: {
          ...visibleDays,
          ...modifiers,
        },
      });
    }

    if (didFocusChange || phrases !== prevPhrases) {
      // set the appropriate CalendarDay phrase based on focusedInput
      const chooseAvailableDate = getChooseAvailableDatePhrase(phrases, focusedInput);

      this.setState({
        phrases: {
          ...phrases,
          chooseAvailableDate,
        },
      });
    }
  }

  onDayClick(day, e) {
    const { keepOpenOnDateSelect, minimumNights, onBlur } = this.props;
    if (e) e.preventDefault();
    if (this.isBlocked(day)) return;

    const { focusedInput, onFocusChange, onClose } = this.props;
    let { startDate, endDate } = this.props;

    if (focusedInput === START_DATE) {
      onFocusChange(END_DATE);

      startDate = day;

      if (isInclusivelyAfterDay(day, endDate)) {
        endDate = null;
      }
    } else if (focusedInput === END_DATE) {
      const firstAllowedEndDate = startDate && startDate.clone().add(minimumNights, 'days');

      if (!startDate) {
        endDate = day;
        onFocusChange(START_DATE);
      } else if (isInclusivelyAfterDay(day, firstAllowedEndDate)) {
        endDate = day;
        if (!keepOpenOnDateSelect) {
          onFocusChange(null);
          onClose({ startDate, endDate });
        }
      } else {
        startDate = day;
        endDate = null;
      }
    }

    this.props.onDatesChange({ startDate, endDate });
    onBlur();
  }

  onDayMouseEnter(day) {
    if (this.isTouchDevice) return;
    const {
      startDate,
      endDate,
      focusedInput,
      minimumNights,
    } = this.props;
    const { hoverDate, visibleDays } = this.state;

    if (focusedInput) {
      let modifiers = {};
      modifiers = this.deleteModifier(modifiers, hoverDate, 'hovered');
      modifiers = this.addModifier(modifiers, day, 'hovered');

      if (startDate && !endDate && focusedInput === END_DATE) {
        if (isAfterDay(hoverDate, startDate)) {
          const endSpan = hoverDate.clone().add(1, 'day');
          modifiers = this.deleteModifierFromRange(modifiers, startDate, endSpan, 'hovered-span');
        }

        if (!this.isBlocked(day) && isAfterDay(day, startDate)) {
          const endSpan = day.clone().add(1, 'day');
          modifiers = this.addModifierToRange(modifiers, startDate, endSpan, 'hovered-span');
        }
      }

      if (!startDate && endDate && focusedInput === START_DATE) {
        if (isBeforeDay(hoverDate, endDate)) {
          modifiers = this.deleteModifierFromRange(modifiers, hoverDate, endDate, 'hovered-span');
        }

        if (!this.isBlocked(day) && isBeforeDay(day, endDate)) {
          modifiers = this.addModifierToRange(modifiers, day, endDate, 'hovered-span');
        }
      }

      if (startDate) {
        if (isSameDay(day, startDate)) {
          const newStartSpan = startDate.clone().add(1, 'day');
          const newEndSpan = startDate.clone().add(minimumNights + 1, 'days');
          modifiers = this.addModifierToRange(
            modifiers,
            newStartSpan,
            newEndSpan,
            'after-hovered-start',
          );
        }
      }

      this.setState({
        hoverDate: day,
        visibleDays: {
          ...visibleDays,
          ...modifiers,
        },
      });
    }
  }

  onDayMouseLeave(day) {
    const { startDate, endDate, minimumNights } = this.props;
    const { hoverDate, visibleDays } = this.state;
    if (this.isTouchDevice || !hoverDate) return;

    let modifiers = {};
    modifiers = this.deleteModifier(modifiers, hoverDate, 'hovered');

    if (startDate && !endDate && isAfterDay(hoverDate, startDate)) {
      const endSpan = hoverDate.clone().add(1, 'day');
      modifiers = this.deleteModifierFromRange(modifiers, startDate, endSpan, 'hovered-span');
    }

    if (!startDate && endDate && isAfterDay(endDate, hoverDate)) {
      modifiers = this.deleteModifierFromRange(modifiers, hoverDate, endDate, 'hovered-span');
    }

    if (startDate && isSameDay(day, startDate)) {
      const startSpan = startDate.clone().add(1, 'day');
      const endSpan = startDate.clone().add(minimumNights + 1, 'days');
      modifiers = this.deleteModifierFromRange(modifiers, startSpan, endSpan, 'after-hovered-start');
    }

    this.setState({
      hoverDate: null,
      visibleDays: {
        ...visibleDays,
        ...modifiers,
      },
    });
  }

  onPrevMonthClick() {
    const { onPrevMonthClick, numberOfMonths, enableOutsideDays } = this.props;
    const { currentMonth, visibleDays } = this.state;

    const newVisibleDays = {};
    Object.keys(visibleDays).sort().slice(0, numberOfMonths + 1).forEach((month) => {
      newVisibleDays[month] = visibleDays[month];
    });

    const prevMonth = currentMonth.clone().subtract(2, 'months');
    const prevMonthVisibleDays = getVisibleDays(prevMonth, 1, enableOutsideDays, true);

    const newCurrentMonth = currentMonth.clone().subtract(1, 'month');
    this.setState({
      currentMonth: newCurrentMonth,
      visibleDays: {
        ...newVisibleDays,
        ...this.getModifiers(prevMonthVisibleDays),
      },
    });

    onPrevMonthClick(newCurrentMonth.clone());
  }

  onNextMonthClick() {
    const { onNextMonthClick, numberOfMonths, enableOutsideDays } = this.props;
    const { currentMonth, visibleDays } = this.state;

    const newVisibleDays = {};
    Object.keys(visibleDays).sort().slice(1).forEach((month) => {
      newVisibleDays[month] = visibleDays[month];
    });

    const nextMonth = currentMonth.clone().add(numberOfMonths + 1, 'month');
    const nextMonthVisibleDays = getVisibleDays(nextMonth, 1, enableOutsideDays, true);

    const newCurrentMonth = currentMonth.clone().add(1, 'month');
    this.setState({
      currentMonth: newCurrentMonth,
      visibleDays: {
        ...newVisibleDays,
        ...this.getModifiers(nextMonthVisibleDays),
      },
    });

    onNextMonthClick(newCurrentMonth.clone());
  }

  onMultiplyScrollableMonths() {
    const { numberOfMonths, enableOutsideDays } = this.props;
    const { currentMonth, visibleDays } = this.state;

    const numberOfVisibleMonths = Object.keys(visibleDays).length;
    const nextMonth = currentMonth.clone().add(numberOfVisibleMonths, 'month');
    const newVisibleDays = getVisibleDays(nextMonth, numberOfMonths, enableOutsideDays, true);

    this.setState({
      visibleDays: {
        ...visibleDays,
        ...this.getModifiers(newVisibleDays),
      },
    });
  }

  getFirstFocusableDay(newMonth) {
    const {
      startDate,
      endDate,
      focusedInput,
      minimumNights,
      numberOfMonths,
    } = this.props;

    let focusedDate = newMonth.clone().startOf('month');
    if (focusedInput === START_DATE && startDate) {
      focusedDate = startDate.clone();
    } else if (focusedInput === END_DATE && !endDate && startDate) {
      focusedDate = startDate.clone().add(minimumNights, 'days');
    } else if (focusedInput === END_DATE && endDate) {
      focusedDate = endDate.clone();
    }

    if (this.isBlocked(focusedDate)) {
      const days = [];
      const lastVisibleDay = newMonth.clone().add(numberOfMonths - 1, 'months').endOf('month');
      let currentDay = focusedDate.clone();
      while (!isAfterDay(currentDay, lastVisibleDay)) {
        currentDay = currentDay.clone().add(1, 'day');
        days.push(currentDay);
      }

      const viableDays = days.filter(day => !this.isBlocked(day));

      if (viableDays.length > 0) {
        ([focusedDate] = viableDays);
      }
    }

    return focusedDate;
  }

  getModifiers(visibleDays) {
    const modifiers = {};
    Object.keys(visibleDays).forEach((month) => {
      modifiers[month] = {};
      visibleDays[month].forEach((day) => {
        modifiers[month][toISODateString(day)] = this.getModifiersForDay(day);
      });
    });

    return modifiers;
  }

  getModifiersForDay(day) {
    return new Set(Object.keys(this.modifiers).filter(modifier => this.modifiers[modifier](day)));
  }

  getStateForNewMonth(nextProps) {
    const {
      initialVisibleMonth,
      numberOfMonths,
      enableOutsideDays,
      orientation,
      startDate,
    } = nextProps;
    const initialVisibleMonthThunk = initialVisibleMonth || (
      startDate ? () => startDate : () => this.today
    );
    const currentMonth = initialVisibleMonthThunk();
    const withoutTransitionMonths = orientation === VERTICAL_SCROLLABLE;
    const visibleDays = this.getModifiers(getVisibleDays(
      currentMonth,
      numberOfMonths,
      enableOutsideDays,
      withoutTransitionMonths,
    ));
    return { currentMonth, visibleDays };
  }

  setDayPickerRef(ref) {
    this.dayPicker = ref;
  }

  addModifier(updatedDays, day, modifier) {
    const { numberOfMonths: numberOfVisibleMonths, enableOutsideDays, orientation } = this.props;
    const { currentMonth: firstVisibleMonth, visibleDays } = this.state;

    let currentMonth = firstVisibleMonth;
    let numberOfMonths = numberOfVisibleMonths;
    if (orientation !== VERTICAL_SCROLLABLE) {
      currentMonth = currentMonth.clone().subtract(1, 'month');
      numberOfMonths += 2;
    }
    if (!day || !isDayVisible(day, currentMonth, numberOfMonths, enableOutsideDays)) {
      return updatedDays;
    }

    const iso = toISODateString(day);

    let updatedDaysAfterAddition = { ...updatedDays };
    if (enableOutsideDays) {
      const monthsToUpdate = Object.keys(visibleDays).filter(monthKey => (
        Object.keys(visibleDays[monthKey]).indexOf(iso) > -1
      ));

      updatedDaysAfterAddition = monthsToUpdate.reduce((days, monthIso) => {
        const month = updatedDays[monthIso] || visibleDays[monthIso];
        const modifiers = new Set(month[iso]);
        modifiers.add(modifier);
        return {
          ...days,
          [monthIso]: {
            ...month,
            [iso]: modifiers,
          },
        };
      }, updatedDaysAfterAddition);
    } else {
      const monthIso = toISOMonthString(day);
      const month = updatedDays[monthIso] || visibleDays[monthIso];

      const modifiers = new Set(month[iso]);
      modifiers.add(modifier);
      updatedDaysAfterAddition = {
        ...updatedDaysAfterAddition,
        [monthIso]: {
          ...month,
          [iso]: modifiers,
        },
      };
    }

    return updatedDaysAfterAddition;
  }

  addModifierToRange(updatedDays, start, end, modifier) {
    let days = updatedDays;

    let spanStart = start.clone();
    while (isBeforeDay(spanStart, end)) {
      days = this.addModifier(days, spanStart, modifier);
      spanStart = spanStart.clone().add(1, 'day');
    }

    return days;
  }

  deleteModifier(updatedDays, day, modifier) {
    const { numberOfMonths: numberOfVisibleMonths, enableOutsideDays, orientation } = this.props;
    const { currentMonth: firstVisibleMonth, visibleDays } = this.state;

    let currentMonth = firstVisibleMonth;
    let numberOfMonths = numberOfVisibleMonths;
    if (orientation !== VERTICAL_SCROLLABLE) {
      currentMonth = currentMonth.clone().subtract(1, 'month');
      numberOfMonths += 2;
    }
    if (!day || !isDayVisible(day, currentMonth, numberOfMonths, enableOutsideDays)) {
      return updatedDays;
    }

    const iso = toISODateString(day);

    let updatedDaysAfterDeletion = { ...updatedDays };
    if (enableOutsideDays) {
      const monthsToUpdate = Object.keys(visibleDays).filter(monthKey => (
        Object.keys(visibleDays[monthKey]).indexOf(iso) > -1
      ));

      updatedDaysAfterDeletion = monthsToUpdate.reduce((days, monthIso) => {
        const month = updatedDays[monthIso] || visibleDays[monthIso];
        const modifiers = new Set(month[iso]);
        modifiers.delete(modifier);
        return {
          ...days,
          [monthIso]: {
            ...month,
            [iso]: modifiers,
          },
        };
      }, updatedDaysAfterDeletion);
    } else {
      const monthIso = toISOMonthString(day);
      const month = updatedDays[monthIso] || visibleDays[monthIso];

      const modifiers = new Set(month[iso]);
      modifiers.delete(modifier);
      updatedDaysAfterDeletion = {
        ...updatedDaysAfterDeletion,
        [monthIso]: {
          ...month,
          [iso]: modifiers,
        },
      };
    }

    return updatedDaysAfterDeletion;
  }

  deleteModifierFromRange(updatedDays, start, end, modifier) {
    let days = updatedDays;

    let spanStart = start.clone();
    while (isBeforeDay(spanStart, end)) {
      days = this.deleteModifier(days, spanStart, modifier);
      spanStart = spanStart.clone().add(1, 'day');
    }

    return days;
  }

  doesNotMeetMinimumNights(day) {
    const {
      startDate,
      isOutsideRange,
      focusedInput,
      minimumNights,
    } = this.props;
    if (focusedInput !== END_DATE) return false;

    if (startDate) {
      const dayDiff = day.diff(startDate.clone().startOf('day').hour(12), 'days');
      return dayDiff < minimumNights && dayDiff >= 0;
    }
    return isOutsideRange(moment(day).subtract(minimumNights, 'days'));
  }

  isDayAfterHoveredStartDate(day) {
    const { startDate, endDate, minimumNights } = this.props;
    const { hoverDate } = this.state || {};
    return !!startDate && !endDate && !this.isBlocked(day) && isNextDay(hoverDate, day) &&
      minimumNights > 0 && isSameDay(hoverDate, startDate);
  }

  isEndDate(day) {
    return isSameDay(day, this.props.endDate);
  }

  isHovered(day) {
    const { hoverDate } = this.state || {};
    const { focusedInput } = this.props;
    return !!focusedInput && isSameDay(day, hoverDate);
  }

  isInHoveredSpan(day) {
    const { startDate, endDate } = this.props;
    const { hoverDate } = this.state || {};

    const isForwardRange = !!startDate && !endDate &&
      (day.isBetween(startDate, hoverDate) ||
       isSameDay(hoverDate, day));
    const isBackwardRange = !!endDate && !startDate &&
      (day.isBetween(hoverDate, endDate) ||
       isSameDay(hoverDate, day));

    const isValidDayHovered = hoverDate && !this.isBlocked(hoverDate);

    return (isForwardRange || isBackwardRange) && isValidDayHovered;
  }

  isInSelectedSpan(day) {
    const { startDate, endDate } = this.props;
    return day.isBetween(startDate, endDate);
  }

  isLastInRange(day) {
    return this.isInSelectedSpan(day) && isNextDay(day, this.props.endDate);
  }

  isStartDate(day) {
    return isSameDay(day, this.props.startDate);
  }

  isBlocked(day) {
    const { isDayBlocked, isOutsideRange } = this.props;
    return isDayBlocked(day) || isOutsideRange(day) || this.doesNotMeetMinimumNights(day);
  }

  isToday(day) {
    return isSameDay(day, this.today);
  }

  render() {
    const {
      numberOfMonths,
      orientation,
      monthFormat,
      renderMonth,
      navPrev,
      navNext,
      onOutsideClick,
      withPortal,
      enableOutsideDays,
      firstDayOfWeek,
      hideKeyboardShortcutsPanel,
      daySize,
      focusedInput,
      renderCalendarDay,
      renderDayContents,
      renderCalendarInfo,
      onBlur,
      isFocused,
      showKeyboardShortcuts,
      isRTL,
      weekDayFormat,
      dayAriaLabelFormat,
      verticalHeight,
      noBorder,
      transitionDuration,
    } = this.props;

    const { currentMonth, phrases, visibleDays } = this.state;

    return (
      <DayPicker
        ref={this.setDayPickerRef}
        orientation={orientation}
        enableOutsideDays={enableOutsideDays}
        modifiers={visibleDays}
        numberOfMonths={numberOfMonths}
        onDayClick={this.onDayClick}
        onDayMouseEnter={this.onDayMouseEnter}
        onDayMouseLeave={this.onDayMouseLeave}
        onPrevMonthClick={this.onPrevMonthClick}
        onNextMonthClick={this.onNextMonthClick}
        onMultiplyScrollableMonths={this.onMultiplyScrollableMonths}
        monthFormat={monthFormat}
        renderMonth={renderMonth}
        withPortal={withPortal}
        hidden={!focusedInput}
        initialVisibleMonth={() => currentMonth}
        daySize={daySize}
        onOutsideClick={onOutsideClick}
        navPrev={navPrev}
        navNext={navNext}
        renderCalendarDay={renderCalendarDay}
        renderDayContents={renderDayContents}
        renderCalendarInfo={renderCalendarInfo}
        firstDayOfWeek={firstDayOfWeek}
        hideKeyboardShortcutsPanel={hideKeyboardShortcutsPanel}
        isFocused={isFocused}
        getFirstFocusableDay={this.getFirstFocusableDay}
        onBlur={onBlur}
        showKeyboardShortcuts={showKeyboardShortcuts}
        phrases={phrases}
        isRTL={isRTL}
        weekDayFormat={weekDayFormat}
        dayAriaLabelFormat={dayAriaLabelFormat}
        verticalHeight={verticalHeight}
        noBorder={noBorder}
        transitionDuration={transitionDuration}
      />
    );
  }
}

DayPickerRangeController.propTypes = propTypes;
DayPickerRangeController.defaultProps = defaultProps;