refactor: improve block modularity on server (#758)

lib/blocks/server.ts

@@ -0,0 +1,99 @@
+import { codeDocumentHandler } from '@/blocks/code/server';
+import { imageDocumentHandler } from '@/blocks/image/server';
+import { sheetDocumentHandler } from '@/blocks/sheet/server';
+import { textDocumentHandler } from '@/blocks/text/server';
+import { BlockKind } from '@/components/block';
+import { DataStreamWriter } from 'ai';
+import { Document } from '../db/schema';
+import { saveDocument } from '../db/queries';
+import { Session } from 'next-auth';
+
+export interface SaveDocumentProps {
+  id: string;
+  title: string;
+  kind: BlockKind;
+  content: string;
+  userId: string;
+}
+
+export interface CreateDocumentCallbackProps {
+  id: string;
+  title: string;
+  dataStream: DataStreamWriter;
+  session: Session;
+}
+
+export interface UpdateDocumentCallbackProps {
+  document: Document;
+  description: string;
+  dataStream: DataStreamWriter;
+  session: Session;
+}
+
+export interface DocumentHandler<T = BlockKind> {
+  kind: T;
+  onCreateDocument: (args: CreateDocumentCallbackProps) => Promise<void>;
+  onUpdateDocument: (args: UpdateDocumentCallbackProps) => Promise<void>;
+}
+
+export function createDocumentHandler<T extends BlockKind>(config: {
+  kind: T;
+  onCreateDocument: (params: CreateDocumentCallbackProps) => Promise<string>;
+  onUpdateDocument: (params: UpdateDocumentCallbackProps) => Promise<string>;
+}): DocumentHandler<T> {
+  return {
+    kind: config.kind,
+    onCreateDocument: async (args: CreateDocumentCallbackProps) => {
+      const draftContent = await config.onCreateDocument({
+        id: args.id,
+        title: args.title,
+        dataStream: args.dataStream,
+        session: args.session,
+      });
+
+      if (args.session?.user?.id) {
+        await saveDocument({
+          id: args.id,
+          title: args.title,
+          content: draftContent,
+          kind: config.kind,
+          userId: args.session.user.id,
+        });
+      }
+
+      return;
+    },
+    onUpdateDocument: async (args: UpdateDocumentCallbackProps) => {
+      const draftContent = await config.onUpdateDocument({
+        document: args.document,
+        description: args.description,
+        dataStream: args.dataStream,
+        session: args.session,
+      });
+
+      if (args.session?.user?.id) {
+        await saveDocument({
+          id: args.document.id,
+          title: args.document.title,
+          content: draftContent,
+          kind: config.kind,
+          userId: args.session.user.id,
+        });
+      }
+
+      return;
+    },
+  };
+}
+
+/*
+ * Use this array to define the document handlers for each block kind.
+ */
+export const documentHandlersByBlockKind: Array<DocumentHandler> = [
+  textDocumentHandler,
+  codeDocumentHandler,
+  imageDocumentHandler,
+  sheetDocumentHandler,
+];
+
+export const blockKinds = ['text', 'code', 'image', 'sheet'] as const;