// Copyright 2022 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only

import { createSelector } from 'reselect';
import { pick } from 'lodash';

import type { GetConversationByIdType } from './conversations';
import type { ConversationType } from '../ducks/conversations';
import type { AttachmentType } from '../../types/Attachment';
import type {
  ConversationStoryType,
  MyStoryType,
  ReplyStateType,
  StoryDistributionListWithMembersDataType,
  StorySendStateType,
  StoryViewType,
} from '../../types/Stories';
import type { StateType } from '../reducer';
import type {
  SelectedStoryDataType,
  StoryDataType,
  StoriesStateType,
  AddStoryData,
} from '../ducks/stories';
import { HasStories, MY_STORIES_ID } from '../../types/Stories';
import { ReadStatus } from '../../messages/MessageReadStatus';
import { SendStatus } from '../../messages/MessageSendState';
import { canReply } from './message';
import {
  getContactNameColorSelector,
  getConversationSelector,
  getHideStoryConversationIds,
  getMe,
} from './conversations';
import { getUserConversationId } from './user';
import { getDistributionListSelector } from './storyDistributionLists';
import { getStoriesEnabled } from './items';
import { calculateExpirationTimestamp } from '../../util/expirationTimer';
import { getMessageIdForLogging } from '../../util/idForLogging';
import * as log from '../../logging/log';
import { SIGNAL_ACI } from '../../types/SignalConversation';

export const getStoriesState = (state: StateType): StoriesStateType =>
  state.stories;

export const shouldShowStoriesView = createSelector(
  getStoriesState,
  ({ openedAtTimestamp }): boolean => Boolean(openedAtTimestamp)
);

export const hasSelectedStoryData = createSelector(
  getStoriesState,
  ({ selectedStoryData }): boolean => Boolean(selectedStoryData)
);

export const getSelectedStoryData = createSelector(
  getStoriesState,
  ({ selectedStoryData }): SelectedStoryDataType | undefined =>
    selectedStoryData
);

export const getAddStoryData = createSelector(
  getStoriesState,
  ({ addStoryData }): AddStoryData => addStoryData
);

function sortByRecencyAndUnread(
  storyA: ConversationStoryType,
  storyB: ConversationStoryType
): number {
  if (
    storyA.storyView.sender.uuid === SIGNAL_ACI &&
    storyA.storyView.isUnread
  ) {
    return -1;
  }

  if (
    storyB.storyView.sender.uuid === SIGNAL_ACI &&
    storyB.storyView.isUnread
  ) {
    return 1;
  }

  if (storyA.storyView.isUnread && storyB.storyView.isUnread) {
    return storyA.storyView.timestamp > storyB.storyView.timestamp ? -1 : 1;
  }

  if (storyB.storyView.isUnread) {
    return 1;
  }

  if (storyA.storyView.isUnread) {
    return -1;
  }

  if (storyA.storyView.readAt && storyB.storyView.readAt) {
    return storyA.storyView.readAt > storyB.storyView.readAt ? -1 : 1;
  }

  return storyA.storyView.timestamp > storyB.storyView.timestamp ? -1 : 1;
}

function sortMyStories(storyA: MyStoryType, storyB: MyStoryType): number {
  if (storyA.id === MY_STORIES_ID) {
    return -1;
  }

  if (storyB.id === MY_STORIES_ID) {
    return 1;
  }

  if (!storyA.stories.length) {
    return 1;
  }

  if (!storyB.stories.length) {
    return -1;
  }

  return storyA.stories[0].timestamp > storyB.stories[0].timestamp ? -1 : 1;
}

function getAvatarData(
  conversation: ConversationType
): Pick<
  ConversationType,
  | 'acceptedMessageRequest'
  | 'avatarPath'
  | 'badges'
  | 'color'
  | 'isMe'
  | 'id'
  | 'name'
  | 'profileName'
  | 'sharedGroupNames'
  | 'title'
> {
  return pick(conversation, [
    'acceptedMessageRequest',
    'avatarPath',
    'badges',
    'color',
    'isMe',
    'id',
    'name',
    'profileName',
    'sharedGroupNames',
    'title',
  ]);
}

export function getStoryDownloadableAttachment({
  attachment,
}: StoryDataType): AttachmentType | undefined {
  // See: getStoryDataFromMessageAttributes for how preview gets populated.
  return attachment?.textAttachment?.preview?.image ?? attachment;
}

export function getStoryView(
  conversationSelector: GetConversationByIdType,
  ourConversationId: string | undefined,
  story: StoryDataType
): StoryViewType {
  const sender = pick(conversationSelector(story.sourceUuid || story.source), [
    'acceptedMessageRequest',
    'avatarPath',
    'badges',
    'color',
    'firstName',
    'hideStory',
    'id',
    'isMe',
    'name',
    'profileName',
    'sharedGroupNames',
    'title',
    'uuid',
  ]);

  const {
    attachment,
    expirationStartTimestamp,
    expireTimer,
    readAt,
    timestamp,
  } = story;

  const { sendStateByConversationId } = story;
  let sendState: Array<StorySendStateType> | undefined;
  let views: number | undefined;

  if (sendStateByConversationId) {
    const innerSendState: Array<StorySendStateType> = [];
    let innerViews = 0;

    Object.keys(sendStateByConversationId).forEach(recipientId => {
      const recipient = conversationSelector(recipientId);

      const recipientSendState = sendStateByConversationId[recipient.id];
      if (recipientSendState.status === SendStatus.Viewed) {
        innerViews += 1;
      }

      innerSendState.push({
        ...recipientSendState,
        recipient,
      });
    });

    sendState = innerSendState;
    views = innerViews;
  }

  const messageIdForLogging = getMessageIdForLogging({
    ...pick(story, 'type', 'sourceUuid', 'sourceDevice'),
    sent_at: story.timestamp,
  });

  return {
    attachment,
    canReply: canReply(story, ourConversationId, conversationSelector),
    isHidden: Boolean(sender.hideStory),
    isUnread: story.readStatus === ReadStatus.Unread,
    messageId: story.messageId,
    messageIdForLogging,
    readAt,
    sender,
    sendState,
    timestamp,
    expirationTimestamp: calculateExpirationTimestamp({
      expireTimer,
      expirationStartTimestamp,
    }),
    views,
  };
}

export function getConversationStory(
  conversationSelector: GetConversationByIdType,
  ourConversationId: string | undefined,
  story: StoryDataType
): ConversationStoryType {
  const sender = pick(conversationSelector(story.sourceUuid || story.source), [
    'id',
  ]);

  const conversation = pick(conversationSelector(story.conversationId), [
    'acceptedMessageRequest',
    'avatarPath',
    'color',
    'hideStory',
    'id',
    'name',
    'profileName',
    'sharedGroupNames',
    'sortedGroupMembers',
    'title',
    'left',
  ]);

  const storyView = getStoryView(
    conversationSelector,
    ourConversationId,
    story
  );

  return {
    conversationId: conversation.id,
    group: conversation.id !== sender.id ? conversation : undefined,
    hasReplies: story.hasReplies,
    hasRepliesFromSelf: story.hasRepliesFromSelf,
    isHidden: Boolean(conversation.hideStory),
    storyView,
  };
}

export const getStoryReplies = createSelector(
  getConversationSelector,
  getContactNameColorSelector,
  getMe,
  getStoriesState,
  (
    conversationSelector,
    contactNameColorSelector,
    me,
    { replyState }: Readonly<StoriesStateType>
  ): ReplyStateType | undefined => {
    if (!replyState) {
      return;
    }

    const replies = replyState.replies.map(reply => {
      const conversation =
        reply.type === 'outgoing'
          ? me
          : conversationSelector(reply.sourceUuid || reply.source);

      return {
        author: getAvatarData(conversation),
        ...pick(reply, [
          'body',
          'bodyRanges',
          'deletedForEveryone',
          'id',
          'timestamp',
        ]),
        reactionEmoji: reply.storyReaction?.emoji,
        contactNameColor: contactNameColorSelector(
          reply.conversationId,
          conversation.id
        ),
        conversationId: conversation.id,
        readStatus: reply.readStatus,
      };
    });

    return {
      messageId: replyState.messageId,
      replies,
    };
  }
);

export const getStories = createSelector(
  getConversationSelector,
  getDistributionListSelector,
  getStoriesState,
  getUserConversationId,
  (
    conversationSelector,
    distributionListSelector,
    { stories }: Readonly<StoriesStateType>,
    ourConversationId
  ): {
    hiddenStories: Array<ConversationStoryType>;
    myStories: Array<MyStoryType>;
    stories: Array<ConversationStoryType>;
  } => {
    const hiddenStoriesById = new Map<string, ConversationStoryType>();
    const myStoriesById = new Map<string, MyStoryType>();
    const storiesById = new Map<string, ConversationStoryType>();

    stories.forEach(story => {
      if (story.deletedForEveryone) {
        return;
      }

      // if for some reason this story is already expired (bug)
      // log it and skip it. Unless it's the onboarding story, that story
      // doesn't have an expiration until it is viewed.
      if (
        !story.sourceUuid === SIGNAL_ACI &&
        (calculateExpirationTimestamp(story) ?? 0) < Date.now()
      ) {
        const messageIdForLogging = getMessageIdForLogging({
          ...pick(story, 'type', 'sourceUuid', 'sourceDevice'),
          sent_at: story.timestamp,
        });
        log.warn('selectors/getStories: story already expired', {
          message: messageIdForLogging,
          expireTimer: story.expireTimer,
          expirationStartTimestamp: story.expirationStartTimestamp,
        });
        return;
      }

      const conversationStory = getConversationStory(
        conversationSelector,
        ourConversationId,
        story
      );

      if (story.sendStateByConversationId) {
        let sentId = story.conversationId;
        let sentName = conversationStory.group?.title;

        if (story.storyDistributionListId) {
          const list =
            story.storyDistributionListId === MY_STORIES_ID
              ? { id: MY_STORIES_ID, name: MY_STORIES_ID }
              : distributionListSelector(
                  story.storyDistributionListId.toLowerCase()
                );

          if (!list) {
            return;
          }

          sentId = list.id;
          sentName = list.name;
        }

        if (!sentName) {
          return;
        }

        const storyView = getStoryView(
          conversationSelector,
          ourConversationId,
          story
        );

        const existingMyStory = myStoriesById.get(sentId) || { stories: [] };

        myStoriesById.set(sentId, {
          id: sentId,
          name: sentName,
          stories: [storyView, ...existingMyStory.stories],
        });

        // If it's a group story we still want it to render as part of regular
        // stories or hidden stories.
        if (story.storyDistributionListId) {
          return;
        }
      }

      let storiesMap: Map<string, ConversationStoryType>;
      if (conversationStory.isHidden) {
        storiesMap = hiddenStoriesById;
      } else {
        storiesMap = storiesById;
      }

      const existingConversationStory = storiesMap.get(
        conversationStory.conversationId
      );

      storiesMap.set(conversationStory.conversationId, {
        ...existingConversationStory,
        ...conversationStory,
        hasReplies:
          existingConversationStory?.hasReplies || conversationStory.hasReplies,
        hasRepliesFromSelf:
          existingConversationStory?.hasRepliesFromSelf ||
          conversationStory.hasRepliesFromSelf,
        storyView: conversationStory.storyView,
      });
    });

    return {
      hiddenStories: Array.from(hiddenStoriesById.values()).sort(
        sortByRecencyAndUnread
      ),
      myStories: Array.from(myStoriesById.values()).sort(sortMyStories),
      stories: Array.from(storiesById.values()).sort(sortByRecencyAndUnread),
    };
  }
);

export const getStoriesNotificationCount = createSelector(
  getHideStoryConversationIds,
  getStoriesState,
  (hideStoryConversationIds, { lastOpenedAtTimestamp, stories }): number => {
    const hiddenConversationIds = new Set(hideStoryConversationIds);

    return new Set(
      stories
        .filter(
          story =>
            story.readStatus === ReadStatus.Unread &&
            !story.deletedForEveryone &&
            story.timestamp > (lastOpenedAtTimestamp || 0) &&
            !hiddenConversationIds.has(story.conversationId)
        )
        .map(story => story.conversationId)
    ).size;
  }
);

export const getHasStoriesSelector = createSelector(
  getStoriesEnabled,
  getStoriesState,
  (isEnabled, { stories }) =>
    (conversationId?: string): HasStories | undefined => {
      if (!isEnabled || !conversationId) {
        return;
      }

      const conversationStories = stories.filter(
        story => story.conversationId === conversationId
      );

      if (!conversationStories.length) {
        return;
      }

      return conversationStories.some(
        story =>
          story.readStatus === ReadStatus.Unread && !story.deletedForEveryone
      )
        ? HasStories.Unread
        : HasStories.Read;
    }
);

export const getStoryByIdSelector = createSelector(
  getStoriesState,
  getUserConversationId,
  getDistributionListSelector,
  ({ stories }, ourConversationId, distributionListSelector) =>
    (
      conversationSelector: GetConversationByIdType,
      messageId: string
    ):
      | {
          conversationStory: ConversationStoryType;
          distributionList:
            | Pick<StoryDistributionListWithMembersDataType, 'id' | 'name'>
            | undefined;
          storyView: StoryViewType;
        }
      | undefined => {
      const story = stories.find(item => item.messageId === messageId);

      if (!story) {
        return;
      }

      let distributionList:
        | Pick<StoryDistributionListWithMembersDataType, 'id' | 'name'>
        | undefined;
      if (story.storyDistributionListId) {
        distributionList =
          story.storyDistributionListId === MY_STORIES_ID
            ? { id: MY_STORIES_ID, name: MY_STORIES_ID }
            : distributionListSelector(
                story.storyDistributionListId.toLowerCase()
              );
      }

      return {
        conversationStory: getConversationStory(
          conversationSelector,
          ourConversationId,
          story
        ),
        distributionList,
        storyView: getStoryView(conversationSelector, ourConversationId, story),
      };
    }
);