import { createSelector } from 'reselect';
import { format } from '../../types/PhoneNumber';

import { LocalizerType } from '../../types/Util';
import { StateType } from '../reducer';
import {
  ConversationLookupType,
  ConversationsStateType,
  ConversationType,
} from '../ducks/conversations';

import { getIntl, getRegionCode, getUserNumber } from './user';
import { PropsData as ConversationListItemPropsType } from '../../components/ConversationListItem';
import { BlockedNumberController } from '../../util';

export const getConversations = (state: StateType): ConversationsStateType =>
  state.conversations;

export const getConversationLookup = createSelector(
  getConversations,
  (state: ConversationsStateType): ConversationLookupType => {
    return state.conversationLookup;
  }
);

export const getSelectedConversation = createSelector(
  getConversations,
  (state: ConversationsStateType): string | undefined => {
    return state.selectedConversation;
  }
);

export const getShowArchived = createSelector(
  getConversations,
  (state: ConversationsStateType): boolean => {
    return Boolean(state.showArchived);
  }
);

function getConversationTitle(
  conversation: ConversationType,
  options: { i18n: LocalizerType; ourRegionCode: string }
): string {
  if (conversation.name) {
    return conversation.name;
  }

  if (conversation.type === 'group') {
    const { i18n } = options;

    return i18n('unknown');
  }

  return format(conversation.phoneNumber, options);
}

const collator = new Intl.Collator();

export const _getConversationComparator = (
  i18n: LocalizerType,
  ourRegionCode: string
) => {
  return (left: ConversationType, right: ConversationType): number => {
    const leftTimestamp = left.timestamp;
    const rightTimestamp = right.timestamp;
    if (leftTimestamp && !rightTimestamp) {
      return -1;
    }
    if (rightTimestamp && !leftTimestamp) {
      return 1;
    }
    if (leftTimestamp && rightTimestamp && leftTimestamp !== rightTimestamp) {
      return rightTimestamp - leftTimestamp;
    }

    const leftTitle = getConversationTitle(left, {
      i18n,
      ourRegionCode,
    }).toLowerCase();
    const rightTitle = getConversationTitle(right, {
      i18n,
      ourRegionCode,
    }).toLowerCase();

    return collator.compare(leftTitle, rightTitle);
  };
};
export const getConversationComparator = createSelector(
  getIntl,
  getRegionCode,
  _getConversationComparator
);

export const _getLeftPaneLists = (
  lookup: ConversationLookupType,
  comparator: (left: ConversationType, right: ConversationType) => number,
  selectedConversation?: string
): {
  conversations: Array<ConversationType>;
  archivedConversations: Array<ConversationType>;
  contacts: Array<ConversationType>;
  unreadCount: number;
} => {
  const values = Object.values(lookup);
  const sorted = values.sort(comparator);

  const conversations: Array<ConversationType> = [];
  const archivedConversations: Array<ConversationType> = [];
  const allContacts: Array<ConversationType> = [];

  let unreadCount = 0;
  for (let conversation of sorted) {
    if (selectedConversation === conversation.id) {
      conversation = {
        ...conversation,
        isSelected: true,
      };
    }
    const isBlocked =
      BlockedNumberController.isBlocked(conversation.primaryDevice) ||
      BlockedNumberController.isGroupBlocked(conversation.id);

    if (isBlocked) {
      conversation = {
        ...conversation,
        isBlocked: true,
      };
    }

    // Add Open Group to list as soon as the name has been set
    if (
      conversation.isPublic &&
      (!conversation.name || conversation.name === 'Unknown group')
    ) {
      continue;
    }

    // Show loading icon while fetching messages
    if (conversation.isPublic && !conversation.timestamp) {
      conversation.lastMessage = {
        status: 'sending',
        text: '',
        isRss: false,
      };
    }

    // Remove all invalid conversations and conversatons of devices associated
    //  with cancelled attempted links
    if (!conversation.isPublic && !conversation.activeAt) {
      continue;
    }

    if (conversation.activeAt !== undefined) {
      allContacts.push(conversation);
    }

    if (unreadCount < 9 && conversation.unreadCount > 0) {
      unreadCount += conversation.unreadCount;
    }

    if (conversation.isArchived) {
      archivedConversations.push(conversation);
    } else {
      conversations.push(conversation);
    }
  }

  const filterToPrimary = <
    T extends Array<ConversationType | ConversationListItemPropsType>
  >(
    group: Array<ConversationType | ConversationListItemPropsType>
  ): T => {
    const secondariesToRemove: Array<string> = [];

    group.forEach(device => {
      if (!device.isSecondary) {
        return;
      }

      const devicePrimary = group.find(c => c.id === device.primaryDevice);

      // Remove secondary where primary already exists in group
      if (group.some(c => c === devicePrimary)) {
        secondariesToRemove.push(device.id);
      }
    });

    const filteredGroup = [
      ...new Set(group.filter(c => !secondariesToRemove.find(s => s === c.id))),
    ];

    return filteredGroup as T;
  };

  const contacts: Array<ConversationType> = filterToPrimary(allContacts);
  return {
    conversations,
    archivedConversations,
    contacts,
    unreadCount,
  };
};

export const _getSessionConversationInfo = (
  lookup: ConversationLookupType,
  comparator: (left: ConversationType, right: ConversationType) => number,
  selectedConversation?: string
): {
  conversation: ConversationType | undefined;
  selectedConversation?: string;
} => {
  const values = Object.values(lookup);
  const sorted = values.sort(comparator);

  let conversation;
  const max = sorted.length;

  for (let i = 0; i < max; i += 1) {
    const conv = sorted[i];

    if (conv.id === selectedConversation) {
      conversation = conv;
      break;
    }
  }

  return {
    conversation,
    selectedConversation,
  };
};

export const getLeftPaneLists = createSelector(
  getConversationLookup,
  getConversationComparator,
  getSelectedConversation,
  _getLeftPaneLists
);

export const getSessionConversationInfo = createSelector(
  getConversationLookup,
  getConversationComparator,
  getSelectedConversation,
  _getSessionConversationInfo
);

export const getMe = createSelector(
  [getConversationLookup, getUserNumber],
  (lookup: ConversationLookupType, ourNumber: string): ConversationType => {
    return lookup[ourNumber];
  }
);