From d879c7d45a0d4c6356008a6572277c3e443ce806 Mon Sep 17 00:00:00 2001
From: SwiftHawk <SwiftHawk@SwiftHawk.com>
Date: Mon, 22 Apr 2024 16:24:50 +0500
Subject: [PATCH] feat: added hashes.json in zip

---
 src/pages/home/index.tsx | 10 +++++++++-
 src/pages/sign/index.tsx | 37 ++++++++++++++++++++++++++++++++++---
 src/utils/hash.ts        |  6 +++---
 3 files changed, 46 insertions(+), 7 deletions(-)

diff --git a/src/pages/home/index.tsx b/src/pages/home/index.tsx
index 85586b5..ebea0d4 100644
--- a/src/pages/home/index.tsx
+++ b/src/pages/home/index.tsx
@@ -214,8 +214,16 @@ export const HomePage = () => {
 
     try {
       const stringifiedMeta = JSON.stringify(meta, null, 2)
-
       zip.file('meta.json', stringifiedMeta)
+
+      const metaHash = await getHash(stringifiedMeta)
+      if (!metaHash) return
+
+      const metaHashJson = {
+        [usersPubkey!]: metaHash
+      }
+
+      zip.file('hashes.json', JSON.stringify(metaHashJson, null, 2))
     } catch (err) {
       toast.error('An error occurred in converting meta json to string')
     }
diff --git a/src/pages/sign/index.tsx b/src/pages/sign/index.tsx
index 56c24b0..bfbc6af 100644
--- a/src/pages/sign/index.tsx
+++ b/src/pages/sign/index.tsx
@@ -78,7 +78,27 @@ export const SignDocument = () => {
       return null
     })
 
-    if (!meta) return
+    const hashesFileContent = await readContentOfZipEntry(
+      zip,
+      'hashes.json',
+      'string'
+    )
+
+    if (!hashesFileContent) {
+      setIsLoading(false)
+      return
+    }
+
+    const hashes = await parseJson(hashesFileContent).catch((err) => {
+      console.log('err in parsing the content of hashes.json :>> ', err)
+      toast.error(
+        err.message || 'error occurred in parsing the content of hashes.json'
+      )
+      setIsLoading(false)
+      return null
+    })
+
+    if (!hashes) return
 
     setLoadingSpinnerDesc('Generating hashes for files')
 
@@ -117,12 +137,12 @@ export const SignDocument = () => {
     // if current user is the last signer, then send DMs to all viewers
     if (isLastSigner) {
       for (const viewer of meta.viewers) {
-        await signAndSendToNext(zip, meta, viewer, fileHashes, false)
+        await signAndSendToNext(zip, meta, hashes, viewer, fileHashes, false)
       }
     } else {
       const nextSigner = meta.signers[signerIndex + 1]
 
-      await signAndSendToNext(zip, meta, nextSigner, fileHashes, true)
+      await signAndSendToNext(zip, meta, hashes, nextSigner, fileHashes, true)
     }
 
     setIsLoading(false)
@@ -131,6 +151,7 @@ export const SignDocument = () => {
   const signAndSendToNext = async (
     zip: JSZip,
     meta: any,
+    hashes: any,
     receiver: string,
     fileHashes: {
       [key: string]: string
@@ -155,6 +176,16 @@ export const SignDocument = () => {
     const stringifiedMeta = JSON.stringify(meta, null, 2)
     zip.file('meta.json', stringifiedMeta)
 
+    const metaHash = await getHash(stringifiedMeta)
+    if (!metaHash) return
+
+    hashes = {
+      ...hashes,
+      [usersPubkey!]: metaHash
+    }
+
+    zip.file('hashes.json', JSON.stringify(hashes, null, 2))
+
     const arrayBuffer = await zip
       .generateAsync({
         type: 'arraybuffer',
diff --git a/src/utils/hash.ts b/src/utils/hash.ts
index eb8c8dd..bd2d4e7 100644
--- a/src/utils/hash.ts
+++ b/src/utils/hash.ts
@@ -6,12 +6,12 @@ import { toast } from 'react-toastify'
  * @param arrayBuffer The ArrayBuffer to hash.
  * @returns A Promise resolving to the SHA-256 hash as a hexadecimal string, or null if hashing fails.
  */
-export const getHash = async (arrayBuffer: ArrayBuffer) => {
+export const getHash = async (input: ArrayBuffer | string) => {
   // Compute the SHA-256 hash of the array buffer
-  const hash = await sha256(arrayBuffer).catch((err) => {
+  const hash = await sha256(input).catch((err) => {
     // Handle error if hashing fails
     console.log(`error occurred in hashing arrayBuffer :>> `, err)
-    toast.error(err.message || `error occurred in hashing arrayBuffer`)
+    toast.error(err.message || `error occurred in hashing`)
     return null // Return null if hashing fails
   })