<?php

final class PhabricatorCalendarEventSearchEngine
  extends PhabricatorApplicationSearchEngine {

  private $calendarYear;
  private $calendarMonth;
  private $calendarDay;

  public function getResultTypeDescription() {
    return pht('Calendar Events');
  }

  public function getApplicationClassName() {
    return 'PhabricatorCalendarApplication';
  }

  public function buildSavedQueryFromRequest(AphrontRequest $request) {
    $saved = new PhabricatorSavedQuery();

    $saved->setParameter(
      'rangeStart',
      $this->readDateFromRequest($request, 'rangeStart'));

    $saved->setParameter(
      'rangeEnd',
      $this->readDateFromRequest($request, 'rangeEnd'));

    $saved->setParameter(
      'upcoming',
      $this->readBoolFromRequest($request, 'upcoming'));

    $saved->setParameter(
      'invitedPHIDs',
      $this->readUsersFromRequest($request, 'invited'));

    $saved->setParameter(
      'creatorPHIDs',
      $this->readUsersFromRequest($request, 'creators'));

    $saved->setParameter(
      'isCancelled',
      $request->getStr('isCancelled'));

    $saved->setParameter(
      'display',
      $request->getStr('display'));

    return $saved;
  }

  public function buildQueryFromSavedQuery(PhabricatorSavedQuery $saved) {
    $query = id(new PhabricatorCalendarEventQuery());
    $viewer = $this->requireViewer();
    $timezone = new DateTimeZone($viewer->getTimezoneIdentifier());

    $min_range = $this->getDateFrom($saved)->getEpoch();
    $max_range = $this->getDateTo($saved)->getEpoch();

    if ($this->isMonthView($saved) ||
      $this->isDayView($saved)) {
      list($start_year, $start_month, $start_day) =
        $this->getDisplayYearAndMonthAndDay($saved);

      $start_day = new DateTime(
        "{$start_year}-{$start_month}-{$start_day}",
        $timezone);
      $next = clone $start_day;

      if ($this->isMonthView($saved)) {
        $next->modify('+1 month');
      } else if ($this->isDayView($saved)) {
        $next->modify('+6 day');
      }

      $display_start = $start_day->format('U');
      $display_end = $next->format('U');

      $preferences = $viewer->loadPreferences();
      $pref_week_day = PhabricatorUserPreferences::PREFERENCE_WEEK_START_DAY;

      $start_of_week = $preferences->getPreference($pref_week_day, 0);
      $end_of_week = ($start_of_week + 6) % 7;

      $first_of_month = $start_day->format('w');
      $last_of_month = id(clone $next)->modify('-1 day')->format('w');

      if (!$min_range || ($min_range < $display_start)) {
        $min_range = $display_start;

        if ($this->isMonthView($saved) &&
          $first_of_month !== $start_of_week) {
          $interim_day_num = ($first_of_month + 7 - $start_of_week) % 7;
          $min_range = id(clone $start_day)
            ->modify('-'.$interim_day_num.' days')
            ->format('U');
        }
      }
      if (!$max_range || ($max_range > $display_end)) {
        $max_range = $display_end;

        if ($this->isMonthView($saved) &&
          $last_of_month !== $end_of_week) {
          $interim_day_num = ($end_of_week + 7 - $last_of_month) % 7;
          $max_range = id(clone $next)
            ->modify('+'.$interim_day_num.' days')
            ->format('U');
        }

      }
    }

    if ($saved->getParameter('upcoming')) {
      if ($min_range) {
        $min_range = max(time(), $min_range);
      } else {
        $min_range = time();
      }
    }

    if ($min_range || $max_range) {
      $query->withDateRange($min_range, $max_range);
    }

    $invited_phids = $saved->getParameter('invitedPHIDs');
    if ($invited_phids) {
      $query->withInvitedPHIDs($invited_phids);
    }

    $creator_phids = $saved->getParameter('creatorPHIDs');
    if ($creator_phids) {
      $query->withCreatorPHIDs($creator_phids);
    }

    $is_cancelled = $saved->getParameter('isCancelled');
    switch ($is_cancelled) {
      case 'active':
        $query->withIsCancelled(false);
        break;
      case 'cancelled':
        $query->withIsCancelled(true);
        break;
    }

    return $query;
  }

  public function buildSearchForm(
    AphrontFormView $form,
    PhabricatorSavedQuery $saved) {

    $range_start = $this->getDateFrom($saved);
    $e_start = null;

    $range_end = $this->getDateTo($saved);
    $e_end = null;

    if (!$range_start->isValid()) {
      $this->addError(pht('Start date is not valid.'));
      $e_start = pht('Invalid');
    }

    if (!$range_end->isValid()) {
      $this->addError(pht('End date is not valid.'));
      $e_end = pht('Invalid');
    }

    $start_epoch = $range_start->getEpoch();
    $end_epoch = $range_end->getEpoch();

    if ($start_epoch && $end_epoch && ($start_epoch > $end_epoch)) {
      $this->addError(pht('End date must be after start date.'));
      $e_start = pht('Invalid');
      $e_end = pht('Invalid');
    }

    $upcoming = $saved->getParameter('upcoming');
    $is_cancelled = $saved->getParameter('isCancelled', 'active');
    $display = $saved->getParameter('display', 'month');

    $invited_phids = $saved->getParameter('invitedPHIDs', array());
    $creator_phids = $saved->getParameter('creatorPHIDs', array());
    $resolution_types = array(
      'active' => pht('Active Events Only'),
      'cancelled' => pht('Cancelled Events Only'),
      'both' => pht('Both Cancelled and Active Events'),
    );
    $display_options = array(
      'month' => pht('Month View'),
      'day' => pht('Day View (beta)'),
      'list' => pht('List View'),
    );

    $form
      ->appendControl(
        id(new AphrontFormTokenizerControl())
          ->setDatasource(new PhabricatorPeopleDatasource())
          ->setName('creators')
          ->setLabel(pht('Created By'))
          ->setValue($creator_phids))
      ->appendControl(
        id(new AphrontFormTokenizerControl())
          ->setDatasource(new PhabricatorPeopleDatasource())
          ->setName('invited')
          ->setLabel(pht('Invited'))
          ->setValue($invited_phids))
      ->appendChild(
        id(new AphrontFormDateControl())
          ->setLabel(pht('Occurs After'))
          ->setUser($this->requireViewer())
          ->setName('rangeStart')
          ->setError($e_start)
          ->setValue($range_start))
      ->appendChild(
        id(new AphrontFormDateControl())
          ->setLabel(pht('Occurs Before'))
          ->setUser($this->requireViewer())
          ->setName('rangeEnd')
          ->setError($e_end)
          ->setValue($range_end))
      ->appendChild(
        id(new AphrontFormCheckboxControl())
          ->addCheckbox(
            'upcoming',
            1,
            pht('Show only upcoming events.'),
            $upcoming))
      ->appendChild(
        id(new AphrontFormSelectControl())
          ->setLabel(pht('Cancelled Events'))
          ->setName('isCancelled')
          ->setValue($is_cancelled)
          ->setOptions($resolution_types))
      ->appendChild(
        id(new AphrontFormSelectControl())
          ->setLabel(pht('Display Options'))
          ->setName('display')
          ->setValue($display)
          ->setOptions($display_options));
  }

  protected function getURI($path) {
    return '/calendar/'.$path;
  }

  protected function getBuiltinQueryNames() {
    $names = array(
      'month' => pht('Month View'),
      'day' => pht('Day View'),
      'upcoming' => pht('Upcoming Events'),
      'all' => pht('All Events'),
    );

    return $names;
  }

  public function setCalendarYearAndMonthAndDay($year, $month, $day = null) {
    $this->calendarYear = $year;
    $this->calendarMonth = $month;
    $this->calendarDay = $day;

    return $this;
  }

  public function buildSavedQueryFromBuiltin($query_key) {
    $query = $this->newSavedQuery();
    $query->setQueryKey($query_key);

    switch ($query_key) {
      case 'month':
        return $query->setParameter('display', 'month');
      case 'day':
        return $query->setParameter('display', 'day');
      case 'upcoming':
        return $query->setParameter('upcoming', true);
      case 'all':
        return $query;
    }

    return parent::buildSavedQueryFromBuiltin($query_key);
  }

  protected function getRequiredHandlePHIDsForResultList(
    array $objects,
    PhabricatorSavedQuery $query) {
    $phids = array();
    foreach ($objects as $event) {
      $phids[$event->getUserPHID()] = 1;
    }
    return array_keys($phids);
  }

  protected function renderResultList(
    array $events,
    PhabricatorSavedQuery $query,
    array $handles) {

    if ($this->isMonthView($query)) {
      return $this->buildCalendarView($events, $query, $handles);
    } else if ($this->isDayView($query)) {
      return $this->buildCalendarDayView($events, $query, $handles);
    }

    assert_instances_of($events, 'PhabricatorCalendarEvent');
    $viewer = $this->requireViewer();
    $list = new PHUIObjectItemListView();
    foreach ($events as $event) {
      $href = '/E'.$event->getID();
      $from = phabricator_datetime($event->getDateFrom(), $viewer);
      $to = phabricator_datetime($event->getDateTo(), $viewer);
      $creator_handle = $handles[$event->getUserPHID()];

      $item = id(new PHUIObjectItemView())
        ->setHeader($event->getName())
        ->setHref($href)
        ->addByline(pht('Creator: %s', $creator_handle->renderLink()))
        ->addAttribute(pht('From %s to %s', $from, $to))
        ->addAttribute(id(new PhutilUTF8StringTruncator())
          ->setMaximumGlyphs(64)
          ->truncateString($event->getDescription()));

      $list->addItem($item);
    }

    return $list;
  }

  private function buildCalendarView(
    array $statuses,
    PhabricatorSavedQuery $query,
    array $handles) {
    $viewer = $this->requireViewer();
    $now = time();

    list($start_year, $start_month) =
      $this->getDisplayYearAndMonthAndDay($query);

    $now_year  = phabricator_format_local_time($now, $viewer, 'Y');
    $now_month = phabricator_format_local_time($now, $viewer, 'm');
    $now_day   = phabricator_format_local_time($now, $viewer, 'j');

    if ($start_month == $now_month && $start_year == $now_year) {
      $month_view = new PHUICalendarMonthView(
        $this->getDateFrom($query),
        $this->getDateTo($query),
        $start_month,
        $start_year,
        $now_day);
    } else {
      $month_view = new PHUICalendarMonthView(
        $this->getDateFrom($query),
        $this->getDateTo($query),
        $start_month,
        $start_year);
    }

    $month_view->setUser($viewer);

    $phids = mpull($statuses, 'getUserPHID');

    foreach ($statuses as $status) {
      $viewer_is_invited = $status->getIsUserInvited($viewer->getPHID());

      $event = new AphrontCalendarEventView();
      $event->setEpochRange($status->getDateFrom(), $status->getDateTo());
      $event->setIsAllDay($status->getIsAllDay());
      $event->setIcon($status->getIcon());

      $name_text = $handles[$status->getUserPHID()]->getName();
      $status_text = $status->getName();
      $event->setUserPHID($status->getUserPHID());
      $event->setDescription(pht('%s (%s)', $name_text, $status_text));
      $event->setName($status_text);
      $event->setEventID($status->getID());
      $event->setViewerIsInvited($viewer_is_invited);
      $month_view->addEvent($event);
    }

    $month_view->setBrowseURI(
      $this->getURI('query/'.$query->getQueryKey().'/'));

    return $month_view;
  }

  private function buildCalendarDayView(
    array $statuses,
    PhabricatorSavedQuery $query,
    array $handles) {
    $viewer = $this->requireViewer();
    list($start_year, $start_month, $start_day) =
      $this->getDisplayYearAndMonthAndDay($query);

    $day_view = new PHUICalendarDayView(
      $this->getDateFrom($query),
      $this->getDateTo($query),
      $start_year,
      $start_month,
      $start_day);

    $day_view->setUser($viewer);

    $phids = mpull($statuses, 'getUserPHID');

    foreach ($statuses as $status) {
      if ($status->getIsCancelled()) {
        continue;
      }

      $viewer_is_invited = $status->getIsUserInvited($viewer->getPHID());

      $event = new AphrontCalendarEventView();
      $event->setEventID($status->getID());
      $event->setEpochRange($status->getDateFrom(), $status->getDateTo());
      $event->setIsAllDay($status->getIsAllDay());
      $event->setIcon($status->getIcon());
      $event->setViewerIsInvited($viewer_is_invited);

      $event->setName($status->getName());
      $event->setURI('/'.$status->getMonogram());
      $day_view->addEvent($event);
    }

    $day_view->setBrowseURI(
      $this->getURI('query/'.$query->getQueryKey().'/'));

    return $day_view;
  }

  private function getDisplayYearAndMonthAndDay(
    PhabricatorSavedQuery $query) {
    $viewer = $this->requireViewer();
    if ($this->calendarYear && $this->calendarMonth) {
      $start_year = $this->calendarYear;
      $start_month = $this->calendarMonth;
      $start_day = $this->calendarDay ? $this->calendarDay : 1;
    } else {
      $epoch = $this->getDateFrom($query)->getEpoch();
      if (!$epoch) {
        $epoch = $this->getDateTo($query)->getEpoch();
        if (!$epoch) {
          $epoch = time();
        }
      }
      if ($this->isMonthView($query)) {
        $day = 1;
      } else {
        $day = phabricator_format_local_time($epoch, $viewer, 'd');
      }
      $start_year = phabricator_format_local_time($epoch, $viewer, 'Y');
      $start_month = phabricator_format_local_time($epoch, $viewer, 'm');
      $start_day = $day;
    }
    return array($start_year, $start_month, $start_day);
  }

  public function getPageSize(PhabricatorSavedQuery $saved) {
    return $saved->getParameter('limit', 1000);
  }

  private function getDateFrom(PhabricatorSavedQuery $saved) {
    return $this->getDate($saved, 'rangeStart');
  }

  private function getDateTo(PhabricatorSavedQuery $saved) {
    return $this->getDate($saved, 'rangeEnd');
  }

  private function getDate(PhabricatorSavedQuery $saved, $key) {
    $viewer = $this->requireViewer();

    $wild = $saved->getParameter($key);
    if ($wild) {
      $value = AphrontFormDateControlValue::newFromWild($viewer, $wild);
    } else {
      $value = AphrontFormDateControlValue::newFromEpoch(
        $viewer,
        PhabricatorTime::getTodayMidnightDateTime($viewer)->format('U'));
      $value->setEnabled(false);
    }

    $value->setOptional(true);

    return $value;
  }

  private function isMonthView(PhabricatorSavedQuery $query) {
    if ($this->isDayView($query)) {
      return false;
    }
    if ($query->getParameter('display') == 'month') {
      return true;
    }
  }

  private function isDayView(PhabricatorSavedQuery $query) {
    if ($query->getParameter('display') == 'day') {
      return true;
    }
    if ($this->calendarDay) {
      return true;
    }

    return false;
  }
}