feat(offline): add decrypt as zip util

src/utils/zip.ts

@@ -1,6 +1,12 @@
 import JSZip from 'jszip'
 import { toast } from 'react-toastify'
-import { InputFileFormat, OutputByType, OutputType } from '../types'
+import { InputFileFormat, Meta, OutputByType, OutputType } from '../types'
+import { NavigateOptions, To } from 'react-router-dom'
+import { appPublicRoutes } from '../routes'
+import { NostrController } from '../controllers'
+import { decryptArrayBuffer } from './crypto'
+import { hexToNpub, parseJson, SigitStatus, timeout } from '.'
+import { SignerService } from '../services'
 
 /**
  * Read the content of a file within a zip archive.
@@ -9,7 +15,7 @@ import { InputFileFormat, OutputByType, OutputType } from '../types'
  * @param outputType The type of output to return (e.g., 'string', 'arraybuffer', 'uint8array', etc.).
  * @returns A Promise resolving to the content of the file, or null if an error occurs.
  */
-const readContentOfZipEntry = async <T extends OutputType>(
+export const readContentOfZipEntry = async <T extends OutputType>(
   zip: JSZip,
   filePath: string,
   outputType: T
@@ -34,7 +40,7 @@ const readContentOfZipEntry = async <T extends OutputType>(
   })
 }
 
-const loadZip = async (data: InputFileFormat): Promise<JSZip | null> => {
+export const loadZip = async (data: InputFileFormat): Promise<JSZip | null> => {
   try {
     return await JSZip.loadAsync(data)
   } catch (err) {
@@ -46,4 +52,130 @@ const loadZip = async (data: InputFileFormat): Promise<JSZip | null> => {
   }
 }
 
-export { readContentOfZipEntry, loadZip }
+export const decrypt = async (file: File) => {
+  const nostrController = NostrController.getInstance()
+
+  const zip = await loadZip(file)
+  if (!zip) return
+
+  const keysFileContent = await readContentOfZipEntry(
+    zip,
+    'keys.json',
+    'string'
+  )
+
+  if (!keysFileContent) return null
+
+  const parsedKeysJson = await parseJson<{ sender: string; keys: string[] }>(
+    keysFileContent
+  ).catch((err) => {
+    console.log(`Error parsing content of keys.json:`, err)
+    toast.error(err.message || `Error parsing content of keys.json`)
+    return null
+  })
+
+  if (!parsedKeysJson) return
+
+  const encryptedArrayBuffer = await readContentOfZipEntry(
+    zip,
+    'compressed.sigit',
+    'arraybuffer'
+  )
+
+  if (!encryptedArrayBuffer) return
+
+  const { keys, sender } = parsedKeysJson
+
+  for (const key of keys) {
+    // decrypt the encryptionKey, with timeout (duration = 60 seconds)
+    const encryptionKey = await Promise.race([
+      nostrController.nip04Decrypt(sender, key),
+      timeout(60000)
+    ])
+      .then((res) => {
+        return res
+      })
+      .catch((err) => {
+        console.log('err :>> ', err)
+        return null
+      })
+
+    // Return if encryption failed
+    if (!encryptionKey) continue
+
+    const arrayBuffer = await decryptArrayBuffer(
+      encryptedArrayBuffer,
+      encryptionKey
+    ).catch((err) => {
+      console.log('err in decryption:>> ', err)
+      return null
+    })
+
+    if (arrayBuffer) return arrayBuffer
+  }
+
+  return null
+}
+
+type NavigateArgs = { to: To; options?: NavigateOptions }
+export const navigateFromZip = async (file: File, pubkey: `npub1${string}`) => {
+  if (!file.name.endsWith('.sigit.zip')) {
+    toast.error(`Not a SiGit zip file: ${file.name}`)
+  }
+
+  try {
+    let zip = await JSZip.loadAsync(file)
+    if (!zip) {
+      return null
+    }
+
+    let arrayBuffer: ArrayBuffer | undefined
+    if ('keys.json' in zip.files) {
+      // Decrypt
+      const decryptedArrayBuffer = await decrypt(file).catch((err) => {
+        console.error(`error occurred in decryption`, err)
+        toast.error(err.message || `error occurred in decryption`)
+      })
+
+      if (decryptedArrayBuffer) {
+        // Replace the zip and continue processing
+        zip = await JSZip.loadAsync(decryptedArrayBuffer)
+        arrayBuffer = decryptedArrayBuffer
+      }
+    }
+
+    if ('meta.json' in zip.files) {
+      // Check where we need to navigate
+      // Find Meta and process it for signer state
+      const metaContent = await readContentOfZipEntry(
+        zip,
+        'meta.json',
+        'string'
+      )
+      if (metaContent) {
+        const meta = JSON.parse(metaContent) as Meta
+        const signerService = new SignerService(meta)
+
+        const to =
+          signerService.getSignedStatus() === SigitStatus.Complete
+            ? appPublicRoutes.verify
+            : signerService.getNavigate(hexToNpub(pubkey))
+
+        return {
+          to,
+          options: {
+            state: { uploadedZip: arrayBuffer || file }
+          }
+        } as NavigateArgs
+      }
+    }
+
+    return null
+  } catch (err) {
+    console.error('err in processing sigit zip file :>> ', err)
+    if (err instanceof Error) {
+      toast.error(err.message || 'An error occurred in loading zip file.')
+    }
+    return null
+  }
+}