feat: adds chukwumaibezim folder with CsvLoader class

lesson_12/io/io_app/src/main/java/com/codedifferently/lesson12/factory/chukwumaibezim/CsvLoader.java

@@ -0,0 +1,98 @@
+package com.codedifferently.lesson12.factory.mohamedibrahim;
+
+import com.codedifferently.lesson12.factory.LibraryCsvDataLoader;
+import com.codedifferently.lesson12.models.CheckoutModel;
+import com.codedifferently.lesson12.models.LibraryDataModel;
+import com.codedifferently.lesson12.models.LibraryGuestModel;
+import com.codedifferently.lesson12.models.MediaItemModel;
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import org.springframework.stereotype.Service;
+
+@Service
+public class CsvLoader implements LibraryCsvDataLoader {
+
+ @Override
+ public LibraryDataModel loadData() throws IOException {
+ LibraryDataModel libraryData = new LibraryDataModel();
+
+ libraryData.guests = readGuestList("csv/guests.csv");
+ libraryData.mediaItems = readMediaItems("csv/media_items.csv");
+ libraryData.checkedOutItems = readCheckedOutByEmail("csv/checked_out_items.csv");
+
+ // Gives each guest a list of their checked out books.
+ libraryData.guests.forEach(
+ guest ->
+ guest.checkedOutItems =
+ libraryData.checkedOutItems.getOrDefault(guest.email, new ArrayList<>()));
+
+ return libraryData;
+ }
+
+ private List<MediaItemModel> readMediaItems(String path) throws IOException {
+ try (BufferedReader reader = new BufferedReader(new FileReader(path))) {
+ return reader
+ .lines()
+ .skip(1)
+ .map(
+ line -> {
+ String[] parts = line.split(",", 8);
+ MediaItemModel item = new MediaItemModel();
+ item.type = parts[0];
+ item.id = UUID.fromString(parts[1]);
+ item.title = parts[2];
+ item.isbn = parts[3];
+ item.authors = List.of(parts[4]);
+ item.pages = parts[5].isEmpty() ? 0 : Integer.parseInt(parts[5]);
+ item.runtime = parts[6].isEmpty() ? 0 : Integer.parseInt(parts[6]);
+ item.edition = parts[7];
+ return item;
+ })
+ .collect(Collectors.toList());
+ }
+ }
+
+ private List<LibraryGuestModel> readGuestList(String path) throws IOException {
+ try (BufferedReader reader = new BufferedReader(new FileReader(path))) {
+ return reader
+ .lines()
+ .skip(1)
+ .map(
+ line -> {
+ String[] parts = line.split(",");
+ LibraryGuestModel guest = new LibraryGuestModel();
+ guest.type = parts[0];
+ guest.name = parts[1];
+ guest.email = parts[2];
+ return guest;
+ })
+ .collect(Collectors.toList());
+ }
+ }
+
+ private Map<String, List<CheckoutModel>> readCheckedOutByEmail(String path) throws IOException {
+ try (BufferedReader reader = new BufferedReader(new FileReader(path))) {
+ return reader
+ .lines()
+ .skip(1)
+ .map(
+ line -> {
+ String[] parts = line.split(",");
+ CheckoutModel item = new CheckoutModel();
+ item.itemId = UUID.fromString(parts[1]);
+ item.dueDate = Instant.parse(parts[2]);
+ return Map.entry(parts[0], item);
+ })
+ .collect(
+ Collectors.groupingBy(
+ Map.Entry::getKey, Collectors.mapping(Map.Entry::getValue, Collectors.toList())));
+ }
+ }
+}