Added global book list context and useLibrary hook for it

src/App/index.tsx

@@ -1,5 +1,6 @@
 import React from "react";
 import { Route, Switch } from "wouter";
+import { BookListContextProvider } from "~/context";
 
 import { Bookshelf } from "~/pages/Bookshelf";
 import { BookView } from "~/pages/BookView";
@@ -9,11 +10,13 @@ import styles from "./App.module.css";
 
 export const App = () => (
   <div className={styles.container}>
-    <Switch>
-      <Route path="/upload" component={UploadForm} />
-      <Route path="/" component={Bookshelf} />
-      <Route path="/:hash" component={BookView} />
-    </Switch>
+    <BookListContextProvider>
+      <Switch>
+        <Route path="/upload" component={UploadForm} />
+        <Route path="/" component={Bookshelf} />
+        <Route path="/:hash" component={BookView} />
+      </Switch>
+    </BookListContextProvider>
   </div>
 );
 

src/api.ts

@@ -1,4 +1,4 @@
-import { IBook, optionalBookProps, requiredBookProps } from "~/types/book";
+import { IBook, requiredBookProps } from "~/types/book";
 
 import { API_URL } from "./constants";
 
@@ -39,12 +39,11 @@ export const submitFile = async (
   }
 };
 
-export const validateResponse = (
-  content: Record<string, unknown>
-): content is IBook => {
-  for (const key of requiredBookProps)
-    if (!(key in content))
-      throw new Error(`${key} is not specified in server response`);
+export const validateResponse = (content: unknown): content is IBook => {
+  if (content && typeof content === "object")
+    for (const key of requiredBookProps)
+      if (!(key in content))
+        throw new Error(`${key} is not specified in server response`);
 
   return true;
 };

src/context.tsx

@@ -0,0 +1,18 @@
+import React from "react";
+import { useLibrary, UseLibraryReturnTuple } from "./hooks/useLibrary";
+import { IBook } from "./types/book";
+
+export const BookListContext = React.createContext<UseLibraryReturnTuple>([
+  [],
+  (book: IBook) => {},
+]);
+
+export const BookListContextProvider: React.FC = ({ children }) => {
+  const library = useLibrary();
+
+  return (
+    <BookListContext.Provider value={library}>
+      {children}
+    </BookListContext.Provider>
+  );
+};

src/hooks/useLibrary.ts

@@ -0,0 +1,38 @@
+import { useEffect, useState } from "react";
+import { IBook } from "~/types/book";
+import {
+  getBookList,
+  getTitleList,
+  setBook,
+  updateTitleList,
+} from "~/utils/localStorage";
+
+export type AddBookFT = (book: IBook) => void;
+
+export type UseLibraryReturnTuple = [IBook[], AddBookFT];
+
+export const useLibrary = (): UseLibraryReturnTuple => {
+  const [bookList, setBookList] = useState<IBook[]>([]);
+  const [titleList, setTitleList] = useState<string[]>([]);
+
+  const addBook: AddBookFT = (book) => {
+    const key = book.hash || Date.now().toString();
+    if (key && !titleList.includes(key)) {
+      setTitleList([key, ...titleList]);
+      setBookList([book, ...bookList]);
+
+      setBook(key, book);
+    }
+  };
+
+  useEffect(() => {
+    const receivedTitleList = getTitleList();
+
+    setTitleList(receivedTitleList);
+    setBookList(getBookList(receivedTitleList));
+  }, []);
+
+  useEffect(() => updateTitleList(titleList), [titleList]);
+
+  return [bookList, addBook];
+};

src/pages/Bookshelf/AddBook/index.tsx

@@ -3,7 +3,6 @@ import { useLocation } from "wouter";
 
 import plusIcon from "~/assets/plus.svg";
 import styles from "./AddBook.module.css";
-import { BASE_URL } from "~/constants";
 
 export const AddBook = () => {
   const [_, setLocation] = useLocation();

src/pages/Bookshelf/index.tsx

@@ -1,18 +1,13 @@
-import React, { useEffect, useState } from "react";
-import { IBook } from "~/types/book";
+import React, { useContext, useEffect, useState } from "react";
 
 import styles from "./Bookshelf.module.css";
 
 import { BookItem } from "./BookItem";
 import { AddBook } from "./AddBook";
-import { readBooks } from "~/utils/localStorage";
+import { BookListContext } from "~/context";
 
 export const Bookshelf = () => {
-  const [books, setBooks] = useState<IBook[]>([]);
-
-  useEffect(() => {
-    setBooks(readBooks());
-  }, []);
+  const [books] = useContext(BookListContext);
 
   return (
     <div className={styles.container}>

src/pages/UploadForm/index.tsx

@@ -1,16 +1,18 @@
-import React, { useState } from "react";
+import React, { useContext, useState } from "react";
 import { useLocation } from "wouter";
 
 import plusIcon from "~/assets/plus.svg";
 import styles from "./UploadForm.module.css";
 import { submitFile, validateResponse, validState } from "~/api";
-import { saveBook } from "~/utils/localStorage";
+import { BookListContext } from "~/context";
 
 export const UploadForm = () => {
   const [error, setError] = useState("");
   const [loading, setLoading] = useState(false);
   const [_, setLocation] = useLocation();
 
+  const [__, saveBook] = useContext(BookListContext);
+
   const processFile = async (file: File | undefined) => {
     try {
       if (validState(file)) {
@@ -23,7 +25,7 @@ export const UploadForm = () => {
         console.log(validateResponse(res));
 
         if (validateResponse(res)) {
-          saveBook(res, res.hash || Date.now().toString());
+          saveBook(res);
           setLocation("/");
         }
       }

src/utils/localStorage.ts

@@ -1,40 +1,33 @@
 import { IBook } from "~/types/book";
 import { isArrOfStr } from "~/types/utils";
 import { validateResponse } from "~/api";
-import { BookItem } from "~/pages/Bookshelf/BookItem";
 
-const readBookList = <T>(
-  cb: (bookList: string[]) => T,
-  defaultValue: T extends void ? undefined : T
-) => {
-  const bookListStr = localStorage.getItem("list") || "[]";
-  const bookList: unknown = JSON.parse(bookListStr);
+export const getTitleList = () => {
+  const titleListStr = localStorage.getItem("list") || "[]";
+  const titleList: unknown = JSON.parse(titleListStr);
 
-  if (isArrOfStr(bookList)) return cb(bookList);
-  return defaultValue;
+  if (isArrOfStr(titleList)) return titleList;
+  else {
+    localStorage.setItem("list", "[]");
+    return [];
+  }
 };
 
-export const saveBook = (bookObj: IBook, key: string) =>
-  readBookList((bookList) => {
-    if (!bookList.includes(key)) {
-      const newBookList = [key, ...bookList];
+export const getBookList = (titleList: string[]) =>
+  titleList
+    .map<unknown>((hash) => JSON.parse(localStorage.getItem(hash) || "{}"))
+    .filter((obj): obj is IBook => {
+      try {
+        return validateResponse(obj);
+      } catch (err) {
+        if (import.meta.env.NODE_ENV === "development")
+          console.log(err.message);
+        return false;
+      }
+    });
 
-      localStorage.setItem("list", JSON.stringify(newBookList));
-      localStorage.setItem(key, JSON.stringify(bookObj));
-    }
-  }, undefined);
+export const setBook = (key: string, book: IBook) =>
+  localStorage.setItem(key, JSON.stringify(book));
 
-export const readBooks = (): IBook[] =>
-  readBookList(
-    (bookList) =>
-      bookList
-        .map((hash) => JSON.parse(localStorage.getItem(hash) || "{}"))
-        .filter((e) => {
-          try {
-            return validateResponse(e);
-          } catch (err) {
-            return false;
-          }
-        }),
-    []
-  );
+export const updateTitleList = (titleList: string[]) =>
+  localStorage.setItem("list", JSON.stringify(titleList));