src/controllers/NostrController.ts

@@ -378,6 +378,61 @@ export class NostrController extends EventEmitter {
     throw new Error('Login method is undefined')
   }
 
+  /**
+   * Decrypts a given content based on the current login method.
+   *
+   * @param sender - The sender's public key.
+   * @param content - The encrypted content to decrypt.
+   * @returns A promise that resolves to the decrypted content.
+   */
+  nip04Decrypt = async (sender: string, content: string) => {
+    const loginMethod = (store.getState().auth as AuthState).loginMethod
+
+    if (loginMethod === LoginMethods.extension) {
+      const nostr = this.getNostrObject()
+
+      if (!nostr.nip04) {
+        throw new Error(
+          `Your nostr extension does not support nip04 encryption & decryption`
+        )
+      }
+
+      const decrypted = await nostr.nip04.decrypt(sender, content)
+      return decrypted
+    }
+
+    if (loginMethod === LoginMethods.privateKey) {
+      const keys = (store.getState().auth as AuthState).keyPair
+
+      if (!keys) {
+        throw new Error(
+          `Login method is ${LoginMethods.privateKey} but private & public key pair is not found.`
+        )
+      }
+
+      const { private: nsec } = keys
+      const privateKey = nip19.decode(nsec).data as Uint8Array
+
+      const decrypted = await nip04.decrypt(privateKey, sender, content)
+      return decrypted
+    }
+
+    if (loginMethod === LoginMethods.nsecBunker) {
+      const user = new NDKUser({ pubkey: sender })
+
+      this.remoteSigner?.on('authUrl', (authUrl) => {
+        this.emit('nsecbunker-auth', authUrl)
+      })
+
+      if (!this.remoteSigner) throw new Error('Remote signer is undefined.')
+      const decrypted = await this.remoteSigner.decrypt(user, content)
+
+      return decrypted
+    }
+
+    throw new Error('Login method is undefined')
+  }
+
   /**
    * Function will capture the public key from the nostr extension or if no extension present
    * function wil capture the public key from the local storage

src/pages/create/index.tsx

@@ -22,7 +22,7 @@ import JSZip from 'jszip'
 import { MuiFileInput } from 'mui-file-input'
 import { useEffect, useRef, useState } from 'react'
 import { useSelector } from 'react-redux'
-import { useNavigate } from 'react-router-dom'
+import { useLocation, useNavigate } from 'react-router-dom'
 import { toast } from 'react-toastify'
 import { LoadingSpinner } from '../../components/LoadingSpinner'
 import { UserComponent } from '../../components/username'
@@ -33,6 +33,7 @@ import { Meta, ProfileMetadata, User, UserRole } from '../../types'
 import {
   encryptArrayBuffer,
   generateEncryptionKey,
+  generateKeysFile,
   getHash,
   hexToNpub,
   isOnline,
@@ -49,15 +50,15 @@ import { HTML5Backend } from 'react-dnd-html5-backend'
 import type { Identifier, XYCoord } from 'dnd-core'
 import { useDrag, useDrop } from 'react-dnd'
 import saveAs from 'file-saver'
-import CopyModal from '../../components/copyModal'
 import { Event, kinds } from 'nostr-tools'
 
 export const CreatePage = () => {
   const navigate = useNavigate()
+  const location = useLocation()
+  const { uploadedFile } = location.state || {}
+
   const [isLoading, setIsLoading] = useState(false)
   const [loadingSpinnerDesc, setLoadingSpinnerDesc] = useState('')
-  const [openCopyModal, setOpenCopyModel] = useState(false)
-  const [textToCopy, setTextToCopy] = useState('')
 
   const [authUrl, setAuthUrl] = useState<string>()
 
@@ -74,6 +75,12 @@ export const CreatePage = () => {
 
   const nostrController = NostrController.getInstance()
 
+  useEffect(() => {
+    if (uploadedFile) {
+      setSelectedFiles([uploadedFile])
+    }
+  }, [uploadedFile])
+
   useEffect(() => {
     if (usersPubkey) {
       setUsers((prev) => {
@@ -221,57 +228,67 @@ export const CreatePage = () => {
     )
   }
 
-  const handleCreate = async () => {
+  // Validate inputs before proceeding
+  const validateInputs = (): boolean => {
     if (!title.trim()) {
       toast.error('Title can not be empty')
-      return
+      return false
     }
 
     if (users.length === 0) {
       toast.error(
         'No signer/viewer is provided. At least add one signer or viewer.'
       )
-      return
+      return false
     }
 
     if (selectedFiles.length === 0) {
       toast.error('No file is selected. Select at least 1 file')
-      return
+      return false
     }
 
-    setIsLoading(true)
+    return true
-    setLoadingSpinnerDesc('Generating hashes for files')
+  }
 
-    const fileHashes: { [key: string]: string } = {}
+  // Handle errors during file arrayBuffer conversion
-
+  const handleFileError = (file: File) => (err: any) => {
-    // generating file hashes
-    for (const file of selectedFiles) {
-      const arraybuffer = await file.arrayBuffer().catch((err) => {
     console.log(
-          `err while getting arrayBuffer of file ${file.name} :>> `,
+      `Error while getting arrayBuffer of file ${file.name} :>> `,
       err
     )
     toast.error(
-          err.message || `err while getting arrayBuffer of file ${file.name}`
+      err.message || `Error while getting arrayBuffer of file ${file.name}`
     )
     return null
-      })
+  }
 
-      if (!arraybuffer) return
+  // Generate hash for each selected file
+  const generateFileHashes = async (): Promise<{
+    [key: string]: string
+  } | null> => {
+    const fileHashes: { [key: string]: string } = {}
+
+    for (const file of selectedFiles) {
+      const arraybuffer = await file.arrayBuffer().catch(handleFileError(file))
+      if (!arraybuffer) return null
 
       const hash = await getHash(arraybuffer)
-
       if (!hash) {
-        setIsLoading(false)
+        return null
-        return
       }
 
       fileHashes[file.name] = hash
     }
 
+    return fileHashes
+  }
+
+  // Create a zip file with the selected files and sign the event
+  const createZipFile = async (fileHashes: {
+    [key: string]: string
+  }): Promise<{ zip: JSZip; createSignature: string } | null> => {
     const zip = new JSZip()
 
-    // zipping files
     selectedFiles.forEach((file) => {
       zip.file(`files/${file.name}`, file)
     })
@@ -280,6 +297,7 @@ export const CreatePage = () => {
     const viewers = users.filter((user) => user.role === UserRole.viewer)
 
     setLoadingSpinnerDesc('Signing nostr event')
+
     const createSignature = await signEventForMetaFile(
       JSON.stringify({
         signers: signers.map((signer) => hexToNpub(signer.pubkey)),
@@ -290,12 +308,27 @@ export const CreatePage = () => {
       setIsLoading
     )
 
-    if (!createSignature) return
+    if (!createSignature) return null
 
+    try {
+      return {
+        zip,
+        createSignature: JSON.stringify(createSignature, null, 2)
+      }
+    } catch (error) {
+      return null
+    }
+  }
+
+  // Add metadata and file hashes to the zip file
+  const addMetaToZip = async (
+    zip: JSZip,
+    createSignature: string
+  ): Promise<string | null> => {
     // create content for meta file
     const meta: Meta = {
       title,
-      createSignature: JSON.stringify(createSignature, null, 2),
+      createSignature,
       docSignatures: {}
     }
 
@@ -304,68 +337,146 @@ export const CreatePage = () => {
       zip.file('meta.json', stringifiedMeta)
 
       const metaHash = await getHash(stringifiedMeta)
-      if (!metaHash) return
+      if (!metaHash) return null
 
       const metaHashJson = {
         [usersPubkey!]: metaHash
       }
 
       zip.file('hashes.json', JSON.stringify(metaHashJson, null, 2))
+      return metaHash
     } catch (err) {
       console.error(err)
       toast.error('An error occurred in converting meta json to string')
-      return
+      return null
+    }
   }
 
+  // Handle errors during zip file generation
+  const handleZipError = (err: any) => {
+    console.log('Error in zip:>> ', err)
+    setIsLoading(false)
+    toast.error(err.message || 'Error occurred in generating zip file')
+    return null
+  }
+
+  // Generate the zip file
+  const generateZipFile = async (zip: JSZip): Promise<ArrayBuffer | null> => {
     setLoadingSpinnerDesc('Generating zip file')
 
     const arraybuffer = await zip
       .generateAsync({
         type: 'arraybuffer',
         compression: 'DEFLATE',
-        compressionOptions: {
+        compressionOptions: { level: 6 }
-          level: 6
+      })
+      .catch(handleZipError)
+
+    return arraybuffer
   }
-      })
-      .catch((err) => {
-        console.log('err in zip:>> ', err)
-        setIsLoading(false)
-        toast.error(err.message || 'Error occurred in generating zip file')
-        return null
-      })
-
-    if (!arraybuffer) return
-
-    const encryptionKey = await generateEncryptionKey()
 
+  // Encrypt the zip file with the generated encryption key
+  const encryptZipFile = async (
+    arraybuffer: ArrayBuffer,
+    encryptionKey: string
+  ): Promise<ArrayBuffer> => {
     setLoadingSpinnerDesc('Encrypting zip file')
-    const encryptedArrayBuffer = await encryptArrayBuffer(
+    return encryptArrayBuffer(arraybuffer, encryptionKey)
-      arraybuffer,
+  }
-      encryptionKey
-    ).finally(() => setIsLoading(false))
 
+  // create final zip file
+  const createFinalZipFile = async (
+    encryptedArrayBuffer: ArrayBuffer,
+    encryptionKey: string
+  ): Promise<File | null> => {
+    // Get the current timestamp in seconds
+    const unixNow = Math.floor(Date.now() / 1000)
     const blob = new Blob([encryptedArrayBuffer])
-
+    // Create a File object with the Blob data
-    if (await isOnline()) {
+    const file = new File([blob], `compressed.sigit`, {
-      setIsLoading(true)
+      type: 'application/sigit'
-      setLoadingSpinnerDesc('Uploading zip file to file storage.')
-      const fileUrl = await uploadToFileStorage(blob, nostrController)
-        .then((url) => {
-          toast.success('zip file uploaded to file storage')
-          return url
-        })
-        .catch((err) => {
-          console.log('err in upload:>> ', err)
-          setIsLoading(false)
-          toast.error(err.message || 'Error occurred in uploading zip file')
-          return null
     })
 
+    const firstSigner = users.filter((user) => user.role === UserRole.signer)[0]
+
+    const keysFileContent = await generateKeysFile(
+      [firstSigner.pubkey],
+      encryptionKey
+    )
+    if (!keysFileContent) return null
+
+    const zip = new JSZip()
+    zip.file(`compressed.sigit`, file)
+    zip.file('keys.json', keysFileContent)
+
+    const arraybuffer = await zip
+      .generateAsync({
+        type: 'arraybuffer',
+        compression: 'DEFLATE',
+        compressionOptions: { level: 6 }
+      })
+      .catch(handleZipError)
+
+    if (!arraybuffer) return null
+
+    const finalZipFile = new File(
+      [new Blob([arraybuffer])],
+      `${unixNow}.sigit.zip`,
+      {
+        type: 'application/zip'
+      }
+    )
+
+    return finalZipFile
+  }
+
+  const handleOnlineFlow = async (
+    encryptedArrayBuffer: ArrayBuffer,
+    encryptionKey: string
+  ) => {
+    const unixNow = Math.floor(Date.now() / 1000)
+    const blob = new Blob([encryptedArrayBuffer])
+    // Create a File object with the Blob data
+    const file = new File([blob], `compressed-${unixNow}.sigit`, {
+      type: 'application/sigit'
+    })
+
+    const fileUrl = await uploadFile(file)
     if (!fileUrl) return
 
+    await sendDMs(fileUrl, encryptionKey)
+  }
+
+  // Handle errors during file upload
+  const handleUploadError = (err: any) => {
+    console.log('Error in upload:>> ', err)
+    setIsLoading(false)
+    toast.error(err.message || 'Error occurred in uploading file')
+    return null
+  }
+
+  // Upload the file to the storage
+  const uploadFile = async (file: File): Promise<string | null> => {
+    setIsLoading(true)
+    setLoadingSpinnerDesc('Uploading sigit to file storage.')
+
+    const fileUrl = await uploadToFileStorage(file, nostrController)
+      .then((url) => {
+        toast.success('Sigit uploaded to file storage')
+        return url
+      })
+      .catch(handleUploadError)
+
+    return fileUrl
+  }
+
+  // Send DMs to signers and viewers with the file URL
+  const sendDMs = async (fileUrl: string, encryptionKey: string) => {
     setLoadingSpinnerDesc('Sending DM to signers/viewers')
 
-      // send DM to first signer if exists
+    const signers = users.filter((user) => user.role === UserRole.signer)
+    const viewers = users.filter((user) => user.role === UserRole.viewer)
+
     if (signers.length > 0) {
       await sendDM(
         fileUrl,
@@ -376,9 +487,7 @@ export const CreatePage = () => {
         setAuthUrl
       )
     } else {
-        // send DM to all viewers if no signer
       for (const viewer of viewers) {
-          // todo: execute in parallel
         await sendDM(
           fileUrl,
           encryptionKey,
@@ -389,27 +498,60 @@ export const CreatePage = () => {
         )
       }
     }
-      setIsLoading(false)
+  }
 
-      navigate(
+  // Manage offline scenarios for signing or viewing the file
-        `${appPrivateRoutes.sign}?file=${encodeURIComponent(
+  const handleOfflineFlow = async (
-          fileUrl
+    encryptedArrayBuffer: ArrayBuffer,
-        )}&key=${encodeURIComponent(encryptionKey)}`
+    encryptionKey: string
+  ) => {
+    const finalZipFile = await createFinalZipFile(
+      encryptedArrayBuffer,
+      encryptionKey
     )
-    } else {
-      if (signers[0] && signers[0].pubkey === usersPubkey) {
-        // Create a File object with the Blob data
-        const file = new File([blob], `compressed.sigit`, {
-          type: 'application/sigit'
-        })
 
-        navigate(appPrivateRoutes.sign, { state: { file, encryptionKey } })
+    if (!finalZipFile) return
+
+    saveAs(finalZipFile, 'request.sigit.zip')
+  }
+
+  const handleCreate = async () => {
+    if (!validateInputs()) return
+
+    setIsLoading(true)
+    setLoadingSpinnerDesc('Generating hashes for files')
+
+    const fileHashes = await generateFileHashes()
+    if (!fileHashes) return
+
+    const createZipResponse = await createZipFile(fileHashes)
+    if (!createZipResponse) return
+
+    const { zip, createSignature } = createZipResponse
+
+    const metaHash = await addMetaToZip(zip, createSignature)
+    if (!metaHash) return
+
+    setLoadingSpinnerDesc('Generating zip file')
+
+    const arrayBuffer = await generateZipFile(zip)
+    if (!arrayBuffer) return
+
+    const encryptionKey = await generateEncryptionKey()
+
+    setLoadingSpinnerDesc('Encrypting zip file')
+    const encryptedArrayBuffer = await encryptZipFile(
+      arrayBuffer,
+      encryptionKey
+    )
+
+    if (await isOnline()) {
+      await handleOnlineFlow(encryptedArrayBuffer, encryptionKey)
     } else {
-        saveAs(blob, 'request.sigit')
+      await handleOfflineFlow(encryptedArrayBuffer, encryptionKey)
-        setTextToCopy(encryptionKey)
-        setOpenCopyModel(true)
-      }
     }
+
+    navigate(appPrivateRoutes.sign, { state: { arrayBuffer } })
   }
 
   if (authUrl) {
@@ -506,15 +648,6 @@ export const CreatePage = () => {
           </Button>
         </Box>
       </Box>
-      <CopyModal
-        open={openCopyModal}
-        handleClose={() => {
-          setOpenCopyModel(false)
-          navigate(appPrivateRoutes.sign)
-        }}
-        title="Decryption key for Sigit file"
-        textToCopy={textToCopy}
-      />
     </>
   )
 }

src/pages/home/index.tsx

@@ -7,11 +7,61 @@ import {
 } from '@mui/icons-material'
 import { Box, Button, Tooltip, Typography } from '@mui/material'
 import { useNavigate } from 'react-router-dom'
-import { appPrivateRoutes } from '../../routes'
+import { appPrivateRoutes, appPublicRoutes } from '../../routes'
 import styles from './style.module.scss'
+import { useRef } from 'react'
+import JSZip from 'jszip'
+import { toast } from 'react-toastify'
 
 export const HomePage = () => {
   const navigate = useNavigate()
+  const fileInputRef = useRef<HTMLInputElement>(null)
+
+  const handleUploadClick = () => {
+    if (fileInputRef.current) {
+      fileInputRef.current.click()
+    }
+  }
+
+  const handleFileChange = async (
+    event: React.ChangeEvent<HTMLInputElement>
+  ) => {
+    const file = event.target.files?.[0]
+    if (file) {
+      // Check if the file extension is .sigit.zip
+      const fileName = file.name
+      const fileExtension = fileName.slice(-10) // ".sigit.zip" has 10 characters
+      if (fileExtension === '.sigit.zip') {
+        const zip = await JSZip.loadAsync(file).catch((err) => {
+          console.log('err in loading zip file :>> ', err)
+          toast.error(err.message || 'An error occurred in loading zip file.')
+          return null
+        })
+
+        if (!zip) return
+
+        // navigate to sign page if zip contains keys.json
+        if ('keys.json' in zip.files) {
+          return navigate(appPrivateRoutes.sign, {
+            state: { uploadedZip: file }
+          })
+        }
+
+        // navigate to verify page if zip contains meta.json
+        if ('meta.json' in zip.files) {
+          return navigate(appPublicRoutes.verify, {
+            state: { uploadedZip: file }
+          })
+        }
+
+        toast.error('Invalid zip file')
+        return
+      }
+
+      // navigate to create page
+      navigate(appPrivateRoutes.create, { state: { uploadedFile: file } })
+    }
+  }
 
   return (
     <Box className={styles.container}>
@@ -29,10 +79,16 @@ export const HomePage = () => {
             }
           }}
         >
+          <input
+            type="file"
+            ref={fileInputRef}
+            style={{ display: 'none' }}
+            onChange={handleFileChange}
+          />
           <Button
             variant="outlined"
             startIcon={<Upload />}
-            onClick={() => navigate(appPrivateRoutes.sign)}
+            onClick={handleUploadClick}
           >
             Upload
           </Button>

src/pages/sign/internal/displayMeta.tsx

@@ -0,0 +1,426 @@
+import JSZip from 'jszip'
+import {
+  Meta,
+  ProfileMetadata,
+  SignedEventContent,
+  User,
+  UserRole
+} from '../../../types'
+import {
+  Box,
+  IconButton,
+  List,
+  ListItem,
+  ListSubheader,
+  Table,
+  TableBody,
+  TableCell,
+  TableHead,
+  TableRow,
+  Tooltip,
+  Typography,
+  useTheme
+} from '@mui/material'
+import {
+  Download,
+  CheckCircle,
+  Cancel,
+  HourglassTop
+} from '@mui/icons-material'
+import saveAs from 'file-saver'
+import { kinds, Event } from 'nostr-tools'
+import { useState, useEffect } from 'react'
+import { toast } from 'react-toastify'
+import { UserComponent } from '../../../components/username'
+import { MetadataController } from '../../../controllers'
+import {
+  npubToHex,
+  readContentOfZipEntry,
+  shorten,
+  hexToNpub,
+  parseJson
+} from '../../../utils'
+import styles from '../style.module.scss'
+
+type DisplayMetaProps = {
+  meta: Meta
+  zip: JSZip
+  submittedBy: string
+  signers: `npub1${string}`[]
+  viewers: `npub1${string}`[]
+  creatorFileHashes: { [key: string]: string }
+  currentFileHashes: { [key: string]: string | null }
+  signedBy: `npub1${string}`[]
+  nextSigner?: string
+  getPrevSignersSig: (usersNpub: string) => string | null
+}
+
+export const DisplayMeta = ({
+  meta,
+  zip,
+  submittedBy,
+  signers,
+  viewers,
+  creatorFileHashes,
+  currentFileHashes,
+  signedBy,
+  nextSigner,
+  getPrevSignersSig
+}: DisplayMetaProps) => {
+  const theme = useTheme()
+
+  const textColor = theme.palette.getContrastText(
+    theme.palette.background.paper
+  )
+
+  const [metadata, setMetadata] = useState<{ [key: string]: ProfileMetadata }>(
+    {}
+  )
+  const [users, setUsers] = useState<User[]>([])
+
+  useEffect(() => {
+    signers.forEach((signer) => {
+      const hexKey = npubToHex(signer)
+      setUsers((prev) => {
+        if (prev.findIndex((user) => user.pubkey === hexKey) !== -1) return prev
+
+        return [
+          ...prev,
+          {
+            pubkey: hexKey!,
+            role: UserRole.signer
+          }
+        ]
+      })
+    })
+
+    viewers.forEach((viewer) => {
+      const hexKey = npubToHex(viewer)
+      setUsers((prev) => {
+        if (prev.findIndex((user) => user.pubkey === hexKey) !== -1) return prev
+
+        return [
+          ...prev,
+          {
+            pubkey: hexKey!,
+            role: UserRole.viewer
+          }
+        ]
+      })
+    })
+  }, [signers, viewers])
+
+  useEffect(() => {
+    const metadataController = new MetadataController()
+
+    const hexKeys: string[] = [
+      npubToHex(submittedBy)!,
+      ...users.map((user) => user.pubkey)
+    ]
+
+    hexKeys.forEach((key) => {
+      if (!(key in metadata)) {
+        const handleMetadataEvent = (event: Event) => {
+          const metadataContent =
+            metadataController.extractProfileMetadataContent(event)
+
+          if (metadataContent)
+            setMetadata((prev) => ({
+              ...prev,
+              [key]: metadataContent
+            }))
+        }
+
+        metadataController.on(key, (kind: number, event: Event) => {
+          if (kind === kinds.Metadata) {
+            handleMetadataEvent(event)
+          }
+        })
+
+        metadataController
+          .findMetadata(key)
+          .then((metadataEvent) => {
+            if (metadataEvent) handleMetadataEvent(metadataEvent)
+          })
+          .catch((err) => {
+            console.error(`error occurred in finding metadata for: ${key}`, err)
+          })
+      }
+    })
+  }, [users, submittedBy])
+
+  const downloadFile = async (filename: string) => {
+    const arrayBuffer = await readContentOfZipEntry(
+      zip,
+      `files/${filename}`,
+      'arraybuffer'
+    )
+    if (!arrayBuffer) return
+
+    const blob = new Blob([arrayBuffer])
+    saveAs(blob, filename)
+  }
+
+  return (
+    <List
+      sx={{
+        bgcolor: 'background.paper',
+        marginTop: 2
+      }}
+      subheader={
+        <ListSubheader className={styles.subHeader}>Meta Info</ListSubheader>
+      }
+    >
+      <ListItem
+        sx={{
+          marginTop: 1,
+          gap: '15px'
+        }}
+      >
+        <Typography variant="h6" sx={{ color: textColor }}>
+          Submitted By
+        </Typography>
+        {(function () {
+          const profile = metadata[submittedBy]
+          return (
+            <UserComponent
+              pubkey={submittedBy}
+              name={
+                profile?.display_name ||
+                profile?.name ||
+                shorten(hexToNpub(submittedBy))
+              }
+              image={profile?.picture}
+            />
+          )
+        })()}
+      </ListItem>
+      <ListItem
+        sx={{
+          marginTop: 1,
+          flexDirection: 'column',
+          alignItems: 'flex-start'
+        }}
+      >
+        <Typography variant="h6" sx={{ color: textColor }}>
+          Files
+        </Typography>
+        <Box className={styles.filesWrapper}>
+          {Object.entries(currentFileHashes).map(([filename, hash], index) => {
+            const isValidHash = creatorFileHashes[filename] === hash
+
+            return (
+              <Box key={`file-${index}`} className={styles.file}>
+                <Tooltip title="Download File" arrow>
+                  <IconButton onClick={() => downloadFile(filename)}>
+                    <Download />
+                  </IconButton>
+                </Tooltip>
+                <Typography
+                  component="label"
+                  sx={{
+                    color: textColor,
+                    flexGrow: 1
+                  }}
+                >
+                  {filename}
+                </Typography>
+                {isValidHash && (
+                  <Tooltip title="File integrity check passed" arrow>
+                    <CheckCircle sx={{ color: theme.palette.success.light }} />
+                  </Tooltip>
+                )}
+                {!isValidHash && (
+                  <Tooltip title="File integrity check failed" arrow>
+                    <Cancel sx={{ color: theme.palette.error.main }} />
+                  </Tooltip>
+                )}
+              </Box>
+            )
+          })}
+        </Box>
+      </ListItem>
+      <ListItem sx={{ marginTop: 1 }}>
+        <Table>
+          <TableHead>
+            <TableRow>
+              <TableCell className={styles.tableCell}>User</TableCell>
+              <TableCell className={styles.tableCell}>Role</TableCell>
+              <TableCell>Signed Status</TableCell>
+            </TableRow>
+          </TableHead>
+          <TableBody>
+            {users.map((user) => (
+              <DisplayUser
+                key={user.pubkey}
+                meta={meta}
+                user={user}
+                metadata={metadata}
+                signedBy={signedBy}
+                nextSigner={nextSigner}
+                getPrevSignersSig={getPrevSignersSig}
+              />
+            ))}
+          </TableBody>
+        </Table>
+      </ListItem>
+    </List>
+  )
+}
+
+enum PrevSignatureValidationEnum {
+  Pending,
+  Valid,
+  Invalid
+}
+
+enum UserStatus {
+  Viewer = 'Viewer',
+  Awaiting = 'Awaiting Signature',
+  Signed = 'Signed',
+  Pending = 'Pending'
+}
+
+type DisplayUserProps = {
+  meta: Meta
+  user: User
+  metadata: { [key: string]: ProfileMetadata }
+  signedBy: `npub1${string}`[]
+  nextSigner?: string
+  getPrevSignersSig: (usersNpub: string) => string | null
+}
+
+const DisplayUser = ({
+  meta,
+  user,
+  metadata,
+  signedBy,
+  nextSigner,
+  getPrevSignersSig
+}: DisplayUserProps) => {
+  const theme = useTheme()
+
+  const userMeta = metadata[user.pubkey]
+  const [userStatus, setUserStatus] = useState<UserStatus>(UserStatus.Pending)
+  const [prevSignatureStatus, setPreviousSignatureStatus] =
+    useState<PrevSignatureValidationEnum>(PrevSignatureValidationEnum.Pending)
+
+  useEffect(() => {
+    if (user.role === UserRole.viewer) {
+      setUserStatus(UserStatus.Viewer)
+      return
+    }
+
+    // check if user has signed the document
+    const usersNpub = hexToNpub(user.pubkey)
+    if (signedBy.includes(usersNpub)) {
+      setUserStatus(UserStatus.Signed)
+      return
+    }
+
+    // check if user is the next signer
+    if (user.pubkey === nextSigner) {
+      setUserStatus(UserStatus.Awaiting)
+      return
+    }
+  }, [user, nextSigner, signedBy])
+
+  useEffect(() => {
+    const validatePrevSignature = async () => {
+      const handleNullCase = () => {
+        setPreviousSignatureStatus(PrevSignatureValidationEnum.Invalid)
+        return
+      }
+
+      // get previous signers sig from the content of current signers signed event
+      const npub = hexToNpub(user.pubkey)
+      const signedEvent = await parseJson<Event>(
+        meta.docSignatures[npub]
+      ).catch((err) => {
+        console.log(`err in parsing the singed event for ${npub}:>> `, err)
+        toast.error(
+          err.message ||
+            'error occurred in parsing the signed event signature event'
+        )
+        return null
+      })
+
+      if (!signedEvent) return handleNullCase()
+
+      // now that we have signed event of current signer, we'll extract prevSig from its content
+      const parsedContent = await parseJson<SignedEventContent>(
+        signedEvent.content
+      ).catch((err) => {
+        console.log(
+          `an error occurred in parsing the content of signedEvent of ${npub}`,
+          err
+        )
+        toast.error(
+          err.message ||
+            `an error occurred in parsing the content of signedEvent of ${npub}`
+        )
+        return null
+      })
+
+      if (!parsedContent) return handleNullCase()
+
+      const prevSignersSignature = getPrevSignersSig(npub)
+
+      if (!prevSignersSignature) return handleNullCase()
+
+      setPreviousSignatureStatus(
+        parsedContent.prevSig === prevSignersSignature
+          ? PrevSignatureValidationEnum.Valid
+          : PrevSignatureValidationEnum.Invalid
+      )
+    }
+
+    if (userStatus === UserStatus.Signed) {
+      validatePrevSignature()
+    }
+  }, [userStatus, meta.docSignatures, user.pubkey, getPrevSignersSig])
+
+  return (
+    <TableRow>
+      <TableCell className={styles.tableCell}>
+        <UserComponent
+          pubkey={user.pubkey}
+          name={
+            userMeta?.display_name ||
+            userMeta?.name ||
+            shorten(hexToNpub(user.pubkey))
+          }
+          image={userMeta?.picture}
+        />
+      </TableCell>
+      <TableCell className={styles.tableCell}>{user.role}</TableCell>
+      <TableCell>
+        <Box sx={{ display: 'flex', alignItems: 'center', gap: '10px' }}>
+          <Typography component="label">{userStatus}</Typography>
+          {userStatus === UserStatus.Signed && (
+            <>
+              {prevSignatureStatus === PrevSignatureValidationEnum.Valid && (
+                <Tooltip title="Contains valid signature of prev signer" arrow>
+                  <CheckCircle sx={{ color: theme.palette.success.light }} />
+                </Tooltip>
+              )}
+              {prevSignatureStatus === PrevSignatureValidationEnum.Invalid && (
+                <Tooltip
+                  title="Contains invalid signature of prev signer"
+                  arrow
+                >
+                  <Cancel sx={{ color: theme.palette.error.main }} />
+                </Tooltip>
+              )}
+            </>
+          )}
+          {userStatus === UserStatus.Awaiting && (
+            <Tooltip title="Waiting for user's sign" arrow>
+              <HourglassTop />
+            </Tooltip>
+          )}
+        </Box>
+      </TableCell>
+    </TableRow>
+  )
+}

src/pages/verify/index.tsx

@@ -32,14 +32,17 @@ import {
 } from '../../utils'
 import styles from './style.module.scss'
 import { Cancel, CheckCircle } from '@mui/icons-material'
+import { useLocation } from 'react-router-dom'
 
 export const VerifyPage = () => {
   const theme = useTheme()
-
   const textColor = theme.palette.getContrastText(
     theme.palette.background.paper
   )
 
+  const location = useLocation()
+  const { uploadedZip } = location.state || {}
+
   const [isLoading, setIsLoading] = useState(false)
   const [loadingSpinnerDesc, setLoadingSpinnerDesc] = useState('')
 
@@ -62,6 +65,12 @@ export const VerifyPage = () => {
     {}
   )
 
+  useEffect(() => {
+    if (uploadedZip) {
+      setSelectedFile(uploadedZip)
+    }
+  }, [uploadedZip])
+
   useEffect(() => {
     if (zip) {
       const generateCurrentFileHashes = async () => {
@@ -364,7 +373,7 @@ export const VerifyPage = () => {
               onChange={(value) => setSelectedFile(value)}
               InputProps={{
                 inputProps: {
-                  accept: '.zip'
+                  accept: '.sigit.zip'
                 }
               }}
             />

src/utils/misc.ts

@@ -1,5 +1,10 @@
 import axios from 'axios'
-import { EventTemplate } from 'nostr-tools'
+import {
+  EventTemplate,
+  generateSecretKey,
+  getPublicKey,
+  nip04
+} from 'nostr-tools'
 import { MetadataController, NostrController } from '../controllers'
 import { toast } from 'react-toastify'
 import { appPrivateRoutes } from '../routes'
@@ -11,17 +16,12 @@ import { appPrivateRoutes } from '../routes'
  * @returns The URL of the uploaded file.
  */
 export const uploadToFileStorage = async (
-  blob: Blob,
+  file: File,
   nostrController: NostrController
 ) => {
   // Get the current timestamp in seconds
   const unixNow = Math.floor(Date.now() / 1000)
 
-  // Create a File object with the Blob data
-  const file = new File([blob], `compressed-${unixNow}.sigit`, {
-    type: 'application/sigit'
-  })
-
   // Define event metadata for authorization
   const event: EventTemplate = {
     kind: 24242,
@@ -205,3 +205,52 @@ export const signEventForMetaFile = async (
 
   return signedEvent // Return the signed event
 }
+
+/**
+ * Generates the content for keys.json file.
+ *
+ * @param users - An array of public keys.
+ * @param key - The key that will be encrypted for each user.
+ * @returns A promise that resolves to a JSON string containing the sender's public key and encrypted keys, or null if an error occurs.
+ */
+export const generateKeysFile = async (
+  users: string[],
+  key: string
+): Promise<string | null> => {
+  // Generate a random private key to act as the sender
+  const privateKey = generateSecretKey()
+
+  // Calculate the required length to be a multiple of 10
+  const requiredLength = Math.ceil(users.length / 10) * 10
+  const additionalKeysCount = requiredLength - users.length
+
+  if (additionalKeysCount > 0) {
+    // generate random public keys to make the keys array multiple of 10
+    const additionalPubkeys = Array.from({ length: additionalKeysCount }, () =>
+      getPublicKey(generateSecretKey())
+    )
+
+    users.push(...additionalPubkeys)
+  }
+
+  // Encrypt the key for each user's public key
+  const promises = users.map((pubkey) => nip04.encrypt(privateKey, pubkey, key))
+
+  // Wait for all encryption promises to resolve
+  const keys = await Promise.all(promises).catch((err) => {
+    console.log('Error while generating keys :>> ', err)
+    toast.error(err.message || 'An error occurred while generating key')
+    return null
+  })
+
+  // If any encryption promise failed, return null
+  if (!keys) return null
+
+  try {
+    // Return a JSON string containing the sender's public key and encrypted keys
+    return JSON.stringify({ sender: getPublicKey(privateKey), keys })
+  } catch (error) {
+    // Return null if an error occurs during JSON stringification
+    return null
+  }
+}