merge files inital commit

src/merge/useMergeQueue.ts

@@ -0,0 +1,102 @@
+import { useCallback, useState } from 'react';
+import { loadPdfFromFile } from '../pdf/pdfService';
+import {
+  canMergeQueue,
+  createMergeQueueItemId,
+  getReadyMergeQueuePdfs,
+  hasMergeQueueErrors,
+  isMergeQueueLoading,
+  moveMergeQueueItem,
+} from './mergeQueueHelpers';
+import type { MergeQueueItem } from './mergeTypes';
+
+export function useMergeQueue() {
+  const [items, setItems] = useState<MergeQueueItem[]>([]);
+
+  const addFiles = useCallback((files: File[]) => {
+    const pdfFiles = files.filter(
+      (file) =>
+        file.type === 'application/pdf' ||
+        file.name.toLowerCase().endsWith('.pdf')
+    );
+
+    if (pdfFiles.length === 0) return;
+
+    const queuedItems: MergeQueueItem[] = pdfFiles.map((file) => ({
+      id: createMergeQueueItemId(),
+      file,
+      name: file.name,
+      size: file.size,
+      pageCount: null,
+      pdf: null,
+      status: 'loading',
+    }));
+
+    setItems((current) => [...current, ...queuedItems]);
+
+    queuedItems.forEach((item) => {
+      void (async () => {
+        try {
+          const loadedPdf = await loadPdfFromFile(item.file);
+
+          setItems((current) =>
+            current.map((currentItem) =>
+              currentItem.id === item.id
+                ? {
+                    ...currentItem,
+                    pdf: loadedPdf,
+                    pageCount: loadedPdf.pageCount,
+                    status: 'ready',
+                    error: undefined,
+                  }
+                : currentItem
+            )
+          );
+        } catch (error) {
+          console.error(error);
+
+          setItems((current) =>
+            current.map((currentItem) =>
+              currentItem.id === item.id
+                ? {
+                    ...currentItem,
+                    status: 'error',
+                    error: 'Could not load this PDF.',
+                  }
+                : currentItem
+            )
+          );
+        }
+      })();
+    });
+  }, []);
+
+  const removeItem = useCallback((itemId: string) => {
+    setItems((current) => current.filter((item) => item.id !== itemId));
+  }, []);
+
+  const moveItemUp = useCallback((itemId: string) => {
+    setItems((current) => moveMergeQueueItem(current, itemId, 'up'));
+  }, []);
+
+  const moveItemDown = useCallback((itemId: string) => {
+    setItems((current) => moveMergeQueueItem(current, itemId, 'down'));
+  }, []);
+
+  const clearQueue = useCallback(() => {
+    setItems([]);
+  }, []);
+
+  return {
+    items,
+    addFiles,
+    removeItem,
+    moveItemUp,
+    moveItemDown,
+    clearQueue,
+    readyPdfs: getReadyMergeQueuePdfs(items),
+    canMerge: canMergeQueue(items),
+    hasErrors: hasMergeQueueErrors(items),
+    isLoading: isMergeQueueLoading(items),
+  };
+}