No Server, No Database, No Problem: The Client-Heavy Architecture of Follow Sync

A serverless GitHub manager for finding non-mutuals. Uses a client-heavy architecture with GitHub Gists as a database and adaptive caching to respect API limits.

Jul, 2025Completedvercel.app Source

Introduction

After a period of intense work through 2024, I took a necessary step back from development in early 2025. When I was ready to dive back in a few months later, I found my GitHub account buzzing with activity. My network had grown significantly, and I had no easy way to manage it or understand my connections.

My search for a solution led me to some existing tools, like Hesbon-Osoro's follow-for-follow-back project. It was a great starting point, but I quickly identified its limitations. To unfollow someone, I was redirected to their GitHub page to click the button manually, and there was no way to perform bulk actions. This friction sparked an idea. I would build my own tool, not just to solve my own problem, but also as the perfect challenge to reignite my passion for coding.

The Technical Blueprint: Pivoting to the Client

I had two core principles for this project: the architecture had to be simple, and it had to be free to run. I also knew that for a tool like this to be truly useful, it couldn't rely on a shared, easily exhausted API rate limit. The first major decision was to use a GitHub OAuth App, giving every user their own 5,000 requests/hour quota to work with.

My initial impulse was to use Next.js's server capabilities to fetch a user's entire network. However, I quickly realized this would be a dead end for power users. A full network sync for an account with tens of thousands of connections could easily exceed the execution limits on Vercel's free tier. Since the app's primary objective was completeness (you need the full picture to accurately calculate non-mutuals), a partial fetch wasn't an option. This forced a crucial pivot:

Follow Sync would be a client-heavy application. The user's own browser would handle the long-running data fetch, bypassing serverless timeouts entirely.

With the fetching strategy decided, I needed a place to cache the processed data. As I explored options, the solution hit me: why not use GitHub itself? I could leverage GitHub Gists as a user-owned database. For state management, I chose a combination of React Query for server state and Zustand for client state.

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No Server, No Database, No Problem: The Client-Heavy Architecture of Follow Sync

A serverless GitHub manager for finding non-mutuals. Uses a client-heavy architecture with GitHub Gists as a database and adaptive caching to respect API limits.

Jul, 2025Completedvercel.app Source

Introduction

The Technical Blueprint: Pivoting to the Client

Follow Sync would be a client-heavy application. The user's own browser would handle the long-running data fetch, bypassing serverless timeouts entirely.

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import { useEffect } from 'react';
import { useSession } from 'next-auth/react';
import { useGhostStore } from '@/lib/store/ghost';
import { useNetworkStore } from '@/lib/store/network';
import { useSettingsStore } from '@/lib/store/settings';
import { useCacheManager } from './useCacheManager';

const DELAY_BETWEEN_BATCHES = 1000; // 1 second

interface GhostDetectorProps {
  isNetworkReady: boolean;
}

export const useGhostDetector = ({ isNetworkReady }: GhostDetectorProps) => {
  const { data: session } = useSession();
  const accessToken = session?.accessToken;
  const { nonMutuals } = useNetworkStore();
  const { nonMutualsFollowingYou, nonMutualsYouFollow } = nonMutuals;
  const { ghosts, setIsCheckingGhosts } = useGhostStore();
  const { ghostDetectionBatchSize } = useSettingsStore();
  const { updateGhosts } = useCacheManager();

  useEffect(() => {
    const detectGhosts = async () => {
      if (!isNetworkReady || !accessToken) {
        setIsCheckingGhosts(false);
        return;
      }

      setIsCheckingGhosts(true);

      const potentialGhosts = [
        ...nonMutualsYouFollow,
        ...nonMutualsFollowingYou,
      ].filter(
        (user) =>
          user?.followers.totalCount === 0 && user?.following.totalCount === 0
      );

      const newPotentialGhosts = potentialGhosts.filter(
        (potentialGhost) =>
          !ghosts.some(
            (existingGhost) => existingGhost.login === potentialGhost.login
          )
      );

      if (newPotentialGhosts.length === 0) {
        setIsCheckingGhosts(false);
        return;
      }

      const confirmedGhosts = [];

      for (
        let i = 0;
        i < newPotentialGhosts.length;
        i += ghostDetectionBatchSize
      ) {
        const batch = newPotentialGhosts.slice(i, i + ghostDetectionBatchSize);
        const usernames = batch.map((user) => user?.login);

        try {
          const response = await fetch('/api/verify-ghosts', {
            method: 'POST',
            headers: {
              'Content-Type': 'application/json',
            },
            body: JSON.stringify({ usernames }),
          });

          if (response.ok) {
            const { ghosts: ghostUsernames } = await response.json();
            const batchGhosts = batch.filter((user) =>
              ghostUsernames.includes(user?.login)
            );
            confirmedGhosts.push(...batchGhosts);
          }
        } catch (error) {
          console.error('Error verifying ghost batch:', error);
        }

        if (i + ghostDetectionBatchSize < newPotentialGhosts.length) {
          await new Promise((resolve) =>
            setTimeout(resolve, DELAY_BETWEEN_BATCHES)
          );
        }
      }

      if (confirmedGhosts.length > 0) {
        await updateGhosts(confirmedGhosts);
      }

      setIsCheckingGhosts(false);
    };

    detectGhosts();
  }, [
    isNetworkReady,
    nonMutualsFollowingYou,
    nonMutualsYouFollow,
    accessToken,
    ghosts,
    setIsCheckingGhosts,
    ghostDetectionBatchSize,
    updateGhosts,
  ]);
};

import { create } from 'zustand';
import { PAGE_SIZE_LIST } from '../constants';

export type SettingsState = {
  isSettingsModalOpen: boolean;
  showAvatars: boolean;
  ghostDetectionBatchSize: number;
  paginationPageSize: number;
  customStaleTime: number | null;
};

export type SettingsActions = {
  toggleSettingsModal: () => void;
  setShowAvatars: (show: boolean) => void;
  setGhostDetectionBatchSize: (size: number) => void;
  setPaginationPageSize: (size: number) => void;
  setCustomStaleTime: (time: number | null) => void;
  saveSettings: (
    accessToken: string,
    persistChanges: (accessToken: string) => Promise<void>
  ) => Promise<void>;
};

export type SettingsStore = SettingsState & SettingsActions;

export const useSettingsStore = create<SettingsStore>((set) => ({
  isSettingsModalOpen: false,
  showAvatars: true,
  ghostDetectionBatchSize: 10,
  paginationPageSize: PAGE_SIZE_LIST[0],
  customStaleTime: null,
  toggleSettingsModal: () =>
    set((state) => ({ isSettingsModalOpen: !state.isSettingsModalOpen })),
  setShowAvatars: (show) => set({ showAvatars: show }),
  setGhostDetectionBatchSize: (size) => set({ ghostDetectionBatchSize: size }),
  setPaginationPageSize: (size) => set({ paginationPageSize: size }),
  setCustomStaleTime: (time) => set({ customStaleTime: time }),
  saveSettings: async (accessToken, persistChanges) => {
    await persistChanges(accessToken);
  },
}));

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';
import { useSession } from 'next-auth/react';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts, addGhosts } = useGhostStore();
  const { setGistName, setGistData, setTimestamp } = useGistStore();
  const settings = useSettingsStore();

  const { data } = useSession();
  const accessToken = data?.accessToken;

  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  const persistChanges = useCallback(async () => {
    if (!accessToken) return;

    const { network } = useNetworkStore.getState();
    const { ghosts } = useGhostStore.getState();
    const { metadata, gistName } = useGistStore.getState();
    const currentSettings = useSettingsStore.getState();

    if (!network || !metadata) return;
    const newTimestamp = Date.now();
    setTimestamp(newTimestamp);

    const dataToCache: CachedData = {
      network,
      ghosts,
      settings: currentSettings,
      timestamp: newTimestamp,
      metadata,
    };

    await writeCache(accessToken, dataToCache, gistName);
  }, [accessToken, setTimestamp]);

  const updateGhosts = useCallback(
    async (newGhosts: UserInfoFragment[]) => {
      addGhosts(newGhosts);
      await persistChanges();
    },
    [addGhosts, persistChanges]
  );

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    persistChanges,
    updateGhosts,
  };
};

cache.ts

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts,  } = useGhostStore();
  const { setGistName, setGistData, } = useGistStore();
  const settings = useSettingsStore();


  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  // other functions

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    // other functions
  };
};

useFollowManager.ts

import { useSession } from 'next-auth/react';
import { useMutation } from '@tanstack/react-query';
import { toast } from 'sonner';
import { useNetworkStore } from '@/lib/store/network';
import { followUser, unfollowUser } from '@/lib/gql/fetchers';
import { useClientAuthenticatedGraphQLClient } from '@/lib/gql/client';
import { UserInfoFragment } from '@/lib/gql/types';
import { useModalsStore } from '@/lib/store/modals';
import { useCacheManager } from './useCacheManager';

export const useFollowManager = () => {
  const { client } = useClientAuthenticatedGraphQLClient();
  const { data: session } = useSession();
  const { network, setNetwork } = useNetworkStore();
  const { persistChanges } = useCacheManager();
  const { incrementActionCount } = useModalsStore();

  const followMutation = useMutation({
    mutationFn: (userToFollow: UserInfoFragment) => {
      if (!client) throw new Error('GraphQL client not available');
      return followUser({ client, userId: userToFollow.id });
    },
    onMutate: async (userToFollow: UserInfoFragment) => {
      const previousNetwork = network;
      const newFollowing = [...network.following, userToFollow];
      const newNetwork = { ...network, following: newFollowing };
      setNetwork(newNetwork);
      return { previousNetwork };
    },
    onError: (err, userToFollow, context) => {
      if (context?.previousNetwork) {
        setNetwork(context.previousNetwork);
      }
      toast.error(`Failed to follow @${userToFollow.login}: ${err.message}`);
    },
    onSettled: () => {
      if (session?.accessToken) {
        persistChanges();
      }
    },
  });

  const unfollowMutation = useMutation({
    mutationFn: (userToUnfollow: UserInfoFragment) => {
      if (!client) throw new Error('GraphQL client not available');
      return unfollowUser({ client, userId: userToUnfollow.id });
    },
    onMutate: async (userToUnfollow: UserInfoFragment) => {
      const previousNetwork = network;
      const newFollowing = network.following.filter(
        (u) => u.id !== userToUnfollow.id
      );
      const newNetwork = { ...network, following: newFollowing };
      setNetwork(newNetwork);
      return { previousNetwork };
    },
    onError: (err, userToUnfollow, context) => {
      if (context?.previousNetwork) {
        setNetwork(context.previousNetwork);
      }
      toast.error(
        `Failed to unfollow @${userToUnfollow.login}: ${err.message}`
      );
    },
    onSettled: () => {
      if (session?.accessToken) {
        persistChanges();
      }
    },
  });

  return {
    followMutation,
    unfollowMutation,
    incrementActionCount,
  };
};

import { useEffect } from 'react';
import { useSession } from 'next-auth/react';
import { useGhostStore } from '@/lib/store/ghost';
import { useNetworkStore } from '@/lib/store/network';
import { useSettingsStore } from '@/lib/store/settings';
import { useCacheManager } from './useCacheManager';

const DELAY_BETWEEN_BATCHES = 1000; // 1 second

interface GhostDetectorProps {
  isNetworkReady: boolean;
}

export const useGhostDetector = ({ isNetworkReady }: GhostDetectorProps) => {
  const { data: session } = useSession();
  const accessToken = session?.accessToken;
  const { nonMutuals } = useNetworkStore();
  const { nonMutualsFollowingYou, nonMutualsYouFollow } = nonMutuals;
  const { ghosts, setIsCheckingGhosts } = useGhostStore();
  const { ghostDetectionBatchSize } = useSettingsStore();
  const { updateGhosts } = useCacheManager();

  useEffect(() => {
    const detectGhosts = async () => {
      if (!isNetworkReady || !accessToken) {
        setIsCheckingGhosts(false);
        return;
      }

      setIsCheckingGhosts(true);

      const potentialGhosts = [
        ...nonMutualsYouFollow,
        ...nonMutualsFollowingYou,
      ].filter(
        (user) =>
          user?.followers.totalCount === 0 && user?.following.totalCount === 0
      );

      const newPotentialGhosts = potentialGhosts.filter(
        (potentialGhost) =>
          !ghosts.some(
            (existingGhost) => existingGhost.login === potentialGhost.login
          )
      );

      if (newPotentialGhosts.length === 0) {
        setIsCheckingGhosts(false);
        return;
      }

      const confirmedGhosts = [];

      for (
        let i = 0;
        i < newPotentialGhosts.length;
        i += ghostDetectionBatchSize
      ) {
        const batch = newPotentialGhosts.slice(i, i + ghostDetectionBatchSize);
        const usernames = batch.map((user) => user?.login);

        try {
          const response = await fetch('/api/verify-ghosts', {
            method: 'POST',
            headers: {
              'Content-Type': 'application/json',
            },
            body: JSON.stringify({ usernames }),
          });

          if (response.ok) {
            const { ghosts: ghostUsernames } = await response.json();
            const batchGhosts = batch.filter((user) =>
              ghostUsernames.includes(user?.login)
            );
            confirmedGhosts.push(...batchGhosts);
          }
        } catch (error) {
          console.error('Error verifying ghost batch:', error);
        }

        if (i + ghostDetectionBatchSize < newPotentialGhosts.length) {
          await new Promise((resolve) =>
            setTimeout(resolve, DELAY_BETWEEN_BATCHES)
          );
        }
      }

      if (confirmedGhosts.length > 0) {
        await updateGhosts(confirmedGhosts);
      }

      setIsCheckingGhosts(false);
    };

    detectGhosts();
  }, [
    isNetworkReady,
    nonMutualsFollowingYou,
    nonMutualsYouFollow,
    accessToken,
    ghosts,
    setIsCheckingGhosts,
    ghostDetectionBatchSize,
    updateGhosts,
  ]);
};

import { create } from 'zustand';
import { PAGE_SIZE_LIST } from '../constants';

export type SettingsState = {
  isSettingsModalOpen: boolean;
  showAvatars: boolean;
  ghostDetectionBatchSize: number;
  paginationPageSize: number;
  customStaleTime: number | null;
};

export type SettingsActions = {
  toggleSettingsModal: () => void;
  setShowAvatars: (show: boolean) => void;
  setGhostDetectionBatchSize: (size: number) => void;
  setPaginationPageSize: (size: number) => void;
  setCustomStaleTime: (time: number | null) => void;
  saveSettings: (
    accessToken: string,
    persistChanges: (accessToken: string) => Promise<void>
  ) => Promise<void>;
};

export type SettingsStore = SettingsState & SettingsActions;

export const useSettingsStore = create<SettingsStore>((set) => ({
  isSettingsModalOpen: false,
  showAvatars: true,
  ghostDetectionBatchSize: 10,
  paginationPageSize: PAGE_SIZE_LIST[0],
  customStaleTime: null,
  toggleSettingsModal: () =>
    set((state) => ({ isSettingsModalOpen: !state.isSettingsModalOpen })),
  setShowAvatars: (show) => set({ showAvatars: show }),
  setGhostDetectionBatchSize: (size) => set({ ghostDetectionBatchSize: size }),
  setPaginationPageSize: (size) => set({ paginationPageSize: size }),
  setCustomStaleTime: (time) => set({ customStaleTime: time }),
  saveSettings: async (accessToken, persistChanges) => {
    await persistChanges(accessToken);
  },
}));

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';
import { useSession } from 'next-auth/react';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts, addGhosts } = useGhostStore();
  const { setGistName, setGistData, setTimestamp } = useGistStore();
  const settings = useSettingsStore();

  const { data } = useSession();
  const accessToken = data?.accessToken;

  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  const persistChanges = useCallback(async () => {
    if (!accessToken) return;

    const { network } = useNetworkStore.getState();
    const { ghosts } = useGhostStore.getState();
    const { metadata, gistName } = useGistStore.getState();
    const currentSettings = useSettingsStore.getState();

    if (!network || !metadata) return;
    const newTimestamp = Date.now();
    setTimestamp(newTimestamp);

    const dataToCache: CachedData = {
      network,
      ghosts,
      settings: currentSettings,
      timestamp: newTimestamp,
      metadata,
    };

    await writeCache(accessToken, dataToCache, gistName);
  }, [accessToken, setTimestamp]);

  const updateGhosts = useCallback(
    async (newGhosts: UserInfoFragment[]) => {
      addGhosts(newGhosts);
      await persistChanges();
    },
    [addGhosts, persistChanges]
  );

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    persistChanges,
    updateGhosts,
  };
};

cache.ts

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts,  } = useGhostStore();
  const { setGistName, setGistData, } = useGistStore();
  const settings = useSettingsStore();


  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  // other functions

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    // other functions
  };
};

useFollowManager.ts

import { useSession } from 'next-auth/react';
import { useMutation } from '@tanstack/react-query';
import { toast } from 'sonner';
import { useNetworkStore } from '@/lib/store/network';
import { followUser, unfollowUser } from '@/lib/gql/fetchers';
import { useClientAuthenticatedGraphQLClient } from '@/lib/gql/client';
import { UserInfoFragment } from '@/lib/gql/types';
import { useModalsStore } from '@/lib/store/modals';
import { useCacheManager } from './useCacheManager';

export const useFollowManager = () => {
  const { client } = useClientAuthenticatedGraphQLClient();
  const { data: session } = useSession();
  const { network, setNetwork } = useNetworkStore();
  const { persistChanges } = useCacheManager();
  const { incrementActionCount } = useModalsStore();

  const followMutation = useMutation({
    mutationFn: (userToFollow: UserInfoFragment) => {
      if (!client) throw new Error('GraphQL client not available');
      return followUser({ client, userId: userToFollow.id });
    },
    onMutate: async (userToFollow: UserInfoFragment) => {
      const previousNetwork = network;
      const newFollowing = [...network.following, userToFollow];
      const newNetwork = { ...network, following: newFollowing };
      setNetwork(newNetwork);
      return { previousNetwork };
    },
    onError: (err, userToFollow, context) => {
      if (context?.previousNetwork) {
        setNetwork(context.previousNetwork);
      }
      toast.error(`Failed to follow @${userToFollow.login}: ${err.message}`);
    },
    onSettled: () => {
      if (session?.accessToken) {
        persistChanges();
      }
    },
  });

  const unfollowMutation = useMutation({
    mutationFn: (userToUnfollow: UserInfoFragment) => {
      if (!client) throw new Error('GraphQL client not available');
      return unfollowUser({ client, userId: userToUnfollow.id });
    },
    onMutate: async (userToUnfollow: UserInfoFragment) => {
      const previousNetwork = network;
      const newFollowing = network.following.filter(
        (u) => u.id !== userToUnfollow.id
      );
      const newNetwork = { ...network, following: newFollowing };
      setNetwork(newNetwork);
      return { previousNetwork };
    },
    onError: (err, userToUnfollow, context) => {
      if (context?.previousNetwork) {
        setNetwork(context.previousNetwork);
      }
      toast.error(
        `Failed to unfollow @${userToUnfollow.login}: ${err.message}`
      );
    },
    onSettled: () => {
      if (session?.accessToken) {
        persistChanges();
      }
    },
  });

  return {
    followMutation,
    unfollowMutation,
    incrementActionCount,
  };
};

import { useEffect } from 'react';
import { useSession } from 'next-auth/react';
import { useGhostStore } from '@/lib/store/ghost';
import { useNetworkStore } from '@/lib/store/network';
import { useSettingsStore } from '@/lib/store/settings';
import { useCacheManager } from './useCacheManager';

const DELAY_BETWEEN_BATCHES = 1000; // 1 second

interface GhostDetectorProps {
  isNetworkReady: boolean;
}

export const useGhostDetector = ({ isNetworkReady }: GhostDetectorProps) => {
  const { data: session } = useSession();
  const accessToken = session?.accessToken;
  const { nonMutuals } = useNetworkStore();
  const { nonMutualsFollowingYou, nonMutualsYouFollow } = nonMutuals;
  const { ghosts, setIsCheckingGhosts } = useGhostStore();
  const { ghostDetectionBatchSize } = useSettingsStore();
  const { updateGhosts } = useCacheManager();

  useEffect(() => {
    const detectGhosts = async () => {
      if (!isNetworkReady || !accessToken) {
        setIsCheckingGhosts(false);
        return;
      }

      setIsCheckingGhosts(true);

      const potentialGhosts = [
        ...nonMutualsYouFollow,
        ...nonMutualsFollowingYou,
      ].filter(
        (user) =>
          user?.followers.totalCount === 0 && user?.following.totalCount === 0
      );

      const newPotentialGhosts = potentialGhosts.filter(
        (potentialGhost) =>
          !ghosts.some(
            (existingGhost) => existingGhost.login === potentialGhost.login
          )
      );

      if (newPotentialGhosts.length === 0) {
        setIsCheckingGhosts(false);
        return;
      }

      const confirmedGhosts = [];

      for (
        let i = 0;
        i < newPotentialGhosts.length;
        i += ghostDetectionBatchSize
      ) {
        const batch = newPotentialGhosts.slice(i, i + ghostDetectionBatchSize);
        const usernames = batch.map((user) => user?.login);

        try {
          const response = await fetch('/api/verify-ghosts', {
            method: 'POST',
            headers: {
              'Content-Type': 'application/json',
            },
            body: JSON.stringify({ usernames }),
          });

          if (response.ok) {
            const { ghosts: ghostUsernames } = await response.json();
            const batchGhosts = batch.filter((user) =>
              ghostUsernames.includes(user?.login)
            );
            confirmedGhosts.push(...batchGhosts);
          }
        } catch (error) {
          console.error('Error verifying ghost batch:', error);
        }

        if (i + ghostDetectionBatchSize < newPotentialGhosts.length) {
          await new Promise((resolve) =>
            setTimeout(resolve, DELAY_BETWEEN_BATCHES)
          );
        }
      }

      if (confirmedGhosts.length > 0) {
        await updateGhosts(confirmedGhosts);
      }

      setIsCheckingGhosts(false);
    };

    detectGhosts();
  }, [
    isNetworkReady,
    nonMutualsFollowingYou,
    nonMutualsYouFollow,
    accessToken,
    ghosts,
    setIsCheckingGhosts,
    ghostDetectionBatchSize,
    updateGhosts,
  ]);
};

import { useEffect } from 'react';
import { useSession } from 'next-auth/react';
import { useGhostStore } from '@/lib/store/ghost';
import { useNetworkStore } from '@/lib/store/network';
import { useSettingsStore } from '@/lib/store/settings';
import { useCacheManager } from './useCacheManager';

const DELAY_BETWEEN_BATCHES = 1000; // 1 second

interface GhostDetectorProps {
  isNetworkReady: boolean;
}

export const useGhostDetector = ({ isNetworkReady }: GhostDetectorProps) => {
  const { data: session } = useSession();
  const accessToken = session?.accessToken;
  const { nonMutuals } = useNetworkStore();
  const { nonMutualsFollowingYou, nonMutualsYouFollow } = nonMutuals;
  const { ghosts, setIsCheckingGhosts } = useGhostStore();
  const { ghostDetectionBatchSize } = useSettingsStore();
  const { updateGhosts } = useCacheManager();

  useEffect(() => {
    const detectGhosts = async () => {
      if (!isNetworkReady || !accessToken) {
        setIsCheckingGhosts(false);
        return;
      }

      setIsCheckingGhosts(true);

      const potentialGhosts = [
        ...nonMutualsYouFollow,
        ...nonMutualsFollowingYou,
      ].filter(
        (user) =>
          user?.followers.totalCount === 0 && user?.following.totalCount === 0
      );

      const newPotentialGhosts = potentialGhosts.filter(
        (potentialGhost) =>
          !ghosts.some(
            (existingGhost) => existingGhost.login === potentialGhost.login
          )
      );

      if (newPotentialGhosts.length === 0) {
        setIsCheckingGhosts(false);
        return;
      }

      const confirmedGhosts = [];

      for (
        let i = 0;
        i < newPotentialGhosts.length;
        i += ghostDetectionBatchSize
      ) {
        const batch = newPotentialGhosts.slice(i, i + ghostDetectionBatchSize);
        const usernames = batch.map((user) => user?.login);

        try {
          const response = await fetch('/api/verify-ghosts', {
            method: 'POST',
            headers: {
              'Content-Type': 'application/json',
            },
            body: JSON.stringify({ usernames }),
          });

          if (response.ok) {
            const { ghosts: ghostUsernames } = await response.json();
            const batchGhosts = batch.filter((user) =>
              ghostUsernames.includes(user?.login)
            );
            confirmedGhosts.push(...batchGhosts);
          }
        } catch (error) {
          console.error('Error verifying ghost batch:', error);
        }

        if (i + ghostDetectionBatchSize < newPotentialGhosts.length) {
          await new Promise((resolve) =>
            setTimeout(resolve, DELAY_BETWEEN_BATCHES)
          );
        }
      }

      if (confirmedGhosts.length > 0) {
        await updateGhosts(confirmedGhosts);
      }

      setIsCheckingGhosts(false);
    };

    detectGhosts();
  }, [
    isNetworkReady,
    nonMutualsFollowingYou,
    nonMutualsYouFollow,
    accessToken,
    ghosts,
    setIsCheckingGhosts,
    ghostDetectionBatchSize,
    updateGhosts,
  ]);
};

import { create } from 'zustand';
import { PAGE_SIZE_LIST } from '../constants';

export type SettingsState = {
  isSettingsModalOpen: boolean;
  showAvatars: boolean;
  ghostDetectionBatchSize: number;
  paginationPageSize: number;
  customStaleTime: number | null;
};

export type SettingsActions = {
  toggleSettingsModal: () => void;
  setShowAvatars: (show: boolean) => void;
  setGhostDetectionBatchSize: (size: number) => void;
  setPaginationPageSize: (size: number) => void;
  setCustomStaleTime: (time: number | null) => void;
  saveSettings: (
    accessToken: string,
    persistChanges: (accessToken: string) => Promise<void>
  ) => Promise<void>;
};

export type SettingsStore = SettingsState & SettingsActions;

export const useSettingsStore = create<SettingsStore>((set) => ({
  isSettingsModalOpen: false,
  showAvatars: true,
  ghostDetectionBatchSize: 10,
  paginationPageSize: PAGE_SIZE_LIST[0],
  customStaleTime: null,
  toggleSettingsModal: () =>
    set((state) => ({ isSettingsModalOpen: !state.isSettingsModalOpen })),
  setShowAvatars: (show) => set({ showAvatars: show }),
  setGhostDetectionBatchSize: (size) => set({ ghostDetectionBatchSize: size }),
  setPaginationPageSize: (size) => set({ paginationPageSize: size }),
  setCustomStaleTime: (time) => set({ customStaleTime: time }),
  saveSettings: async (accessToken, persistChanges) => {
    await persistChanges(accessToken);
  },
}));

import { create } from 'zustand';
import { PAGE_SIZE_LIST } from '../constants';

export type SettingsState = {
  isSettingsModalOpen: boolean;
  showAvatars: boolean;
  ghostDetectionBatchSize: number;
  paginationPageSize: number;
  customStaleTime: number | null;
};

export type SettingsActions = {
  toggleSettingsModal: () => void;
  setShowAvatars: (show: boolean) => void;
  setGhostDetectionBatchSize: (size: number) => void;
  setPaginationPageSize: (size: number) => void;
  setCustomStaleTime: (time: number | null) => void;
  saveSettings: (
    accessToken: string,
    persistChanges: (accessToken: string) => Promise<void>
  ) => Promise<void>;
};

export type SettingsStore = SettingsState & SettingsActions;

export const useSettingsStore = create<SettingsStore>((set) => ({
  isSettingsModalOpen: false,
  showAvatars: true,
  ghostDetectionBatchSize: 10,
  paginationPageSize: PAGE_SIZE_LIST[0],
  customStaleTime: null,
  toggleSettingsModal: () =>
    set((state) => ({ isSettingsModalOpen: !state.isSettingsModalOpen })),
  setShowAvatars: (show) => set({ showAvatars: show }),
  setGhostDetectionBatchSize: (size) => set({ ghostDetectionBatchSize: size }),
  setPaginationPageSize: (size) => set({ paginationPageSize: size }),
  setCustomStaleTime: (time) => set({ customStaleTime: time }),
  saveSettings: async (accessToken, persistChanges) => {
    await persistChanges(accessToken);
  },
}));

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';
import { useSession } from 'next-auth/react';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts, addGhosts } = useGhostStore();
  const { setGistName, setGistData, setTimestamp } = useGistStore();
  const settings = useSettingsStore();

  const { data } = useSession();
  const accessToken = data?.accessToken;

  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  const persistChanges = useCallback(async () => {
    if (!accessToken) return;

    const { network } = useNetworkStore.getState();
    const { ghosts } = useGhostStore.getState();
    const { metadata, gistName } = useGistStore.getState();
    const currentSettings = useSettingsStore.getState();

    if (!network || !metadata) return;
    const newTimestamp = Date.now();
    setTimestamp(newTimestamp);

    const dataToCache: CachedData = {
      network,
      ghosts,
      settings: currentSettings,
      timestamp: newTimestamp,
      metadata,
    };

    await writeCache(accessToken, dataToCache, gistName);
  }, [accessToken, setTimestamp]);

  const updateGhosts = useCallback(
    async (newGhosts: UserInfoFragment[]) => {
      addGhosts(newGhosts);
      await persistChanges();
    },
    [addGhosts, persistChanges]
  );

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    persistChanges,
    updateGhosts,
  };
};

import { GraphQLClient } from 'graphql-request';
import { toast } from 'sonner';
import { useCallback } from 'react';

import { useNetworkStore } from '@/lib/store/network';
import { useGistStore } from '@/lib/store/gist';
import { useGhostStore } from '@/lib/store/ghost';
import { useSettingsStore } from '@/lib/store/settings';

import { findCacheGist, parseCache, writeCache } from '@/lib/gist';
import { fetchAllUserFollowersAndFollowing } from '@/lib/gql/fetchers';
import {
  GIST_ID_STORAGE_KEY,
  STALE_TIME_LARGE,
  STALE_TIME_MANUAL_ONLY,
  STALE_TIME_MEDIUM,
  STALE_TIME_SMALL,
} from '@/lib/constants';
import { CachedData, ProgressCallbacks } from '@/lib/types';
import { UserInfoFragment } from '@/lib/gql/types';
import { useSession } from 'next-auth/react';

export const useCacheManager = () => {
  const setNetwork = useNetworkStore((state) => state.setNetwork);
  const { setGhosts, addGhosts } = useGhostStore();
  const { setGistName, setGistData, setTimestamp } = useGistStore();
  const settings = useSettingsStore();

  const { data } = useSession();
  const accessToken = data?.accessToken;

  const loadFromCache = useCallback(
    (cachedData: CachedData) => {
      setNetwork(cachedData.network);
      setGhosts(cachedData.ghosts);
      setGistData({
        timestamp: cachedData.timestamp,
        metadata: cachedData.metadata,
      });

      if (cachedData.settings) {
        settings.setShowAvatars(cachedData.settings.showAvatars);
        settings.setGhostDetectionBatchSize(
          cachedData.settings.ghostDetectionBatchSize
        );
        settings.setPaginationPageSize(cachedData.settings.paginationPageSize);
        settings.setCustomStaleTime(cachedData.settings.customStaleTime);
      }
    },
    [setNetwork, setGhosts, setGistData, settings]
  );

  const initializeAndFetchNetwork = useCallback(
    async (
      client: GraphQLClient,
      username: string,
      accessToken: string,
      progress: ProgressCallbacks
    ) => {
      const { show, update, complete, fail } = progress;
      const localGistName = window.localStorage.getItem(GIST_ID_STORAGE_KEY);
      setGistName(localGistName);

      const isForced = useGistStore.getState().forceNextRefresh;
      const currentGistName = useGistStore.getState().gistName;

      if (isForced) {
        useGistStore.getState().setForceNextRefresh(false);
      }

      if (!isForced) {
        const foundGist = await findCacheGist(client, currentGistName);
        if (foundGist) {
          const cachedData = parseCache(foundGist);
          if (cachedData) {
            setGistName(foundGist.name);
            const totalConnections = cachedData.metadata.totalConnections;
            const { customStaleTime } = settings;

            let staleTime = 0;
            if (customStaleTime) {
              staleTime = customStaleTime * 60 * 1000;
            } else if (totalConnections <= 2000) {
              staleTime = STALE_TIME_SMALL;
            } else if (totalConnections <= 10000) {
              staleTime = STALE_TIME_MEDIUM;
            } else if (totalConnections <= 50000) {
              staleTime = STALE_TIME_LARGE;
            } else {
              staleTime = STALE_TIME_MANUAL_ONLY;
            }

            const isStale = Date.now() - cachedData.timestamp > staleTime;
            loadFromCache(cachedData);

            if (!isStale) {
              toast.info('Loaded fresh data from cache.');
              return cachedData.network;
            }

            if (staleTime === STALE_TIME_MANUAL_ONLY) {
              toast.info(
                'Data loaded from cache. Refresh manually for the latest update.'
              );
              return cachedData.network;
            }
          }
        }
      }

      const fetchStart = performance.now();
      show({
        title: 'Syncing Your Network',
        message: 'Fetching connections from GitHub...',
        items: [
          { label: 'Followers', current: 0, total: 0 },
          { label: 'Following', current: 0, total: 0 },
        ],
      });

      try {
        const networkData = await fetchAllUserFollowersAndFollowing({
          client,
          username,
          onProgress: (p) => {
            update([
              {
                label: 'Followers',
                current: p.fetchedFollowers,
                total: p.totalFollowers,
              },
              {
                label: 'Following',
                current: p.fetchedFollowing,
                total: p.totalFollowing,
              },
            ]);
          },
        });

        const fetchEnd = performance.now();
        const fetchDuration = Math.round((fetchEnd - fetchStart) / 1000);
        const followers = networkData.followers.nodes as UserInfoFragment[];
        const following = networkData.following.nodes as UserInfoFragment[];
        const network = { followers, following };
        const timestamp = Date.now();

        const dataToCache: CachedData = {
          network,
          ghosts: [],
          settings,
          timestamp,
          metadata: {
            totalConnections: followers.length + following.length,
            fetchDuration,
            cacheVersion: '1.0',
          },
        };

        const newGist = await writeCache(
          accessToken,
          dataToCache,
          currentGistName
        );

        setNetwork(network);
        setGistData({ timestamp, metadata: dataToCache.metadata });
        setGistName(newGist.id);
        complete();

        return network;
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
      } catch (err: any) {
        fail({ message: err.message || 'Failed to sync network.' });
        throw err;
      }
    },
    [settings, loadFromCache, setGistName, setNetwork, setGistData]
  );

  const persistChanges = useCallback(async () => {
    if (!accessToken) return;

    const { network } = useNetworkStore.getState();
    const { ghosts } = useGhostStore.getState();
    const { metadata, gistName } = useGistStore.getState();
    const currentSettings = useSettingsStore.getState();

    if (!network || !metadata) return;
    const newTimestamp = Date.now();
    setTimestamp(newTimestamp);

    const dataToCache: CachedData = {
      network,
      ghosts,
      settings: currentSettings,
      timestamp: newTimestamp,
      metadata,
    };

    await writeCache(accessToken, dataToCache, gistName);
  }, [accessToken, setTimestamp]);

  const updateGhosts = useCallback(
    async (newGhosts: UserInfoFragment[]) => {
      addGhosts(newGhosts);
      await persistChanges();
    },
    [addGhosts, persistChanges]
  );

  return {
    initializeAndFetchNetwork,
    loadFromCache,
    persistChanges,
    updateGhosts,
  };
};

No Server, No Database, No Problem: The Client-Heavy Architecture of Follow Sync

Introduction

The Technical Blueprint: Pivoting to the Client

Share Project

No Server, No Database, No Problem: The Client-Heavy Architecture of Follow Sync

Introduction

The Technical Blueprint: Pivoting to the Client

Share Project

The "GitHub-as-Infrastructure" Philosophy & Its Trade-offs

The Development Journey: Engineering for the Edge Cases

Challenge 1: Engineering a Rate-Limit-Aware Caching System

Doing the Math

The Adaptive Cache Tiers

Challenge 2: Detecting 'Ghost' Accounts via the Edge

Challenge 3: Building a Responsive UI with Optimistic Updates

Challenge 4: Empowering Users with Custom Settings

Code Spotlight: From Monolith to Modular State Management

Lessons Learned and The Road Ahead

cache.ts

useFollowManager.ts

The "GitHub-as-Infrastructure" Philosophy & Its Trade-offs

The Development Journey: Engineering for the Edge Cases

Challenge 1: Engineering a Rate-Limit-Aware Caching System

Doing the Math

The Adaptive Cache Tiers

Challenge 2: Detecting 'Ghost' Accounts via the Edge

Challenge 3: Building a Responsive UI with Optimistic Updates

Challenge 4: Empowering Users with Custom Settings

Code Spotlight: From Monolith to Modular State Management

Lessons Learned and The Road Ahead

cache.ts

useFollowManager.ts