feat(storage): phase 5 — replace Supabase storage with local filesystem + HMAC evidence serving

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/api/evidence/[...path]/route.ts

@@ -0,0 +1,85 @@
+import { NextRequest, NextResponse } from 'next/server'
+import fs from 'node:fs'
+import path from 'node:path'
+import crypto from 'node:crypto'
+import { getSession } from '@/lib/auth/get-session'
+import { signEvidencePath } from '@/lib/storage/evidence'
+import { asAdmin } from '@/lib/db/with-user'
+import { evidenceFiles } from '@/lib/db/schema'
+import { eq } from 'drizzle-orm'
+
+export const dynamic = 'force-dynamic'
+
+export async function GET(
+  request: NextRequest,
+  { params }: { params: Promise<{ path: string[] }> }
+) {
+  const { path: segments } = await params
+  const filePath = segments.join('/')
+
+  // Verify HMAC token
+  const token = request.nextUrl.searchParams.get('token')
+  if (!token) return new NextResponse('Missing token', { status: 401 })
+  if (token.length !== 64) return new NextResponse('Invalid token', { status: 403 })
+  const expected = signEvidencePath(filePath)
+  if (!crypto.timingSafeEqual(Buffer.from(token, 'hex'), Buffer.from(expected, 'hex'))) {
+    return new NextResponse('Invalid token', { status: 403 })
+  }
+
+  // Verify session
+  const session = await getSession()
+  if (!session) return new NextResponse('Unauthorized', { status: 401 })
+
+  // Authorization: uploader or hse/admin
+  const isPrivileged = ['hse', 'admin'].includes(session.role)
+  if (!isPrivileged) {
+    // Check if user is the uploader
+    const [row] = await asAdmin(db =>
+      db.select({ uploadedBy: evidenceFiles.uploadedBy })
+        .from(evidenceFiles)
+        .where(eq(evidenceFiles.fileUrl, `/api/evidence/${filePath}`))
+        .limit(1)
+    )
+    if (!row || row.uploadedBy !== session.sub) {
+      return new NextResponse('Forbidden', { status: 403 })
+    }
+  }
+
+  // Serve file — path traversal prevention
+  const evidenceDir = process.env.EVIDENCE_DIR
+  if (!evidenceDir) return new NextResponse('Storage not configured', { status: 500 })
+
+  const resolved = path.resolve(path.join(evidenceDir, filePath))
+  if (!resolved.startsWith(path.resolve(evidenceDir))) {
+    return new NextResponse('Forbidden', { status: 403 })
+  }
+
+  if (!fs.existsSync(resolved)) return new NextResponse('Not found', { status: 404 })
+
+  const stat = fs.statSync(resolved)
+  const fileBuffer = fs.readFileSync(resolved)
+
+  // Infer content type from extension
+  const ext = path.extname(filePath).toLowerCase().slice(1)
+  const MIME: Record<string, string> = {
+    jpg: 'image/jpeg', jpeg: 'image/jpeg', png: 'image/png', gif: 'image/gif',
+    webp: 'image/webp', heic: 'image/heic', avif: 'image/avif',
+    mp4: 'video/mp4', mov: 'video/quicktime', webm: 'video/webm',
+    pdf: 'application/pdf',
+    doc: 'application/msword',
+    docx: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
+    xls: 'application/vnd.ms-excel',
+    xlsx: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+  }
+  const contentType = MIME[ext] ?? 'application/octet-stream'
+
+  return new NextResponse(fileBuffer, {
+    status: 200,
+    headers: {
+      'Content-Type': contentType,
+      'Content-Length': String(stat.size),
+      'Cache-Control': 'private, max-age=3600',
+      'Content-Disposition': 'inline',
+    },
+  })
+}

app/api/incidents/route.ts

@@ -1,8 +1,7 @@
 import { NextResponse } from 'next/server'
-import { createClient } from '@/lib/supabase/server'
 import { getSession } from '@/lib/auth/get-session'
 import { validateIncidentInput, validateTypeDetails, type IncidentType, type MedicalStatus } from '@/lib/incidents/validate'
-import { uploadEvidenceFile } from '@/lib/supabase/storage'
+import { uploadEvidenceFile } from '@/lib/storage/evidence'
 import { sendNewIncidentEmail } from '@/lib/notifications/email'
 import { sendWhatsAppMessage } from '@/lib/notifications/whatsapp'
 import { createInAppNotifications } from '@/lib/notifications/in-app'
@@ -148,12 +147,11 @@ async function handlePost(request: Request) {
     })
   })
 
-  // Evidence upload — storage still uses supabase (Phase 5 replaces this)
-  const supabase = await createClient()
+  // Evidence upload — local filesystem storage with HMAC-signed URLs
   const evidenceInserts: Array<typeof evidenceFiles.$inferInsert> = []
   for (const file of files) {
     try {
-      const { publicUrl, hash } = await uploadEvidenceFile(supabase, file, incidentId, 'report', session.sub)
+      const { publicUrl, hash } = await uploadEvidenceFile(file, incidentId, 'report', session.sub)
       evidenceInserts.push({
         incidentId,
         stage: 'report',

components/incidents/evidence-gallery.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import type { EvidenceStage } from '@/lib/supabase/storage'
+import type { EvidenceStage } from '@/lib/storage/evidence'
 
 type EvidenceFile = {
   id: string
@@ -18,12 +18,6 @@ interface Props {
 function isImage(type: string) { return type.startsWith('image/') }
 function isVideo(type: string) { return type.startsWith('video/') }
 
-// Supabase Storage image transform endpoint. Falls back to the original object
-// URL via onError if the project plan has no image transformation.
-function thumbnailUrl(url: string, width = 320): string {
-  if (!url.includes('/storage/v1/object/public/')) return url
-  return `${url.replace('/storage/v1/object/public/', '/storage/v1/render/image/public/')}?width=${width}&quality=60`
-}
 
 export function EvidenceGallery({ files, stage }: Props) {
   const filtered = stage ? files.filter(f => f.stage === stage) : files
@@ -41,14 +35,10 @@ export function EvidenceGallery({ files, stage }: Props) {
         >
           {isImage(file.file_type) ? (
             <img
-              src={thumbnailUrl(file.file_url)}
+              src={file.file_url}
               alt="Evidence"
               loading="lazy"
               className="w-full h-full object-cover"
-              onError={e => {
-                const img = e.currentTarget
-                if (img.src !== file.file_url) img.src = file.file_url
-              }}
             />
           ) : isVideo(file.file_type) ? (
             <div className="w-full h-full flex items-center justify-center text-3xl">🎥</div>

lib/storage/evidence.ts

@@ -0,0 +1,79 @@
+import 'server-only'
+import fs from 'node:fs'
+import path from 'node:path'
+import crypto from 'node:crypto'
+import { fileTypeFromBuffer } from 'file-type'
+
+export type EvidenceStage = 'report' | 'response' | 'investigation' | 'capa' | 'verification'
+
+const ALLOWED_MIME_TYPES = new Set([
+  'image/jpeg', 'image/png', 'image/gif', 'image/webp', 'image/heic', 'image/avif',
+  'video/mp4', 'video/quicktime', 'video/webm', 'video/x-msvideo',
+  'application/pdf',
+  'application/msword',
+  'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
+  'application/vnd.ms-excel',
+  'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+])
+
+function evidenceDir(): string {
+  const dir = process.env.EVIDENCE_DIR
+  if (!dir) throw new Error('EVIDENCE_DIR env var not set')
+  return dir
+}
+
+function hmacSecret(): string {
+  const s = process.env.EVIDENCE_URL_SECRET
+  if (!s) throw new Error('EVIDENCE_URL_SECRET env var not set')
+  return s
+}
+
+export function signEvidencePath(filePath: string): string {
+  return crypto.createHmac('sha256', hmacSecret()).update(filePath).digest('hex')
+}
+
+export function getEvidenceUrl(filePath: string): string {
+  const token = signEvidencePath(filePath)
+  return `/api/evidence/${filePath}?token=${token}`
+}
+
+export async function uploadEvidenceFile(
+  file: File,
+  incidentId: string,
+  stage: EvidenceStage,
+  userId: string,
+): Promise<{ path: string; publicUrl: string; hash: string }> {
+  const isVideo = file.type.startsWith('video/')
+  const maxBytes = isVideo ? 200 * 1024 * 1024 : 10 * 1024 * 1024
+  if (file.size > maxBytes) {
+    throw new Error(`File too large: max ${isVideo ? '200MB' : '10MB'} for this file type`)
+  }
+
+  const buffer = await file.arrayBuffer()
+  const detected = await fileTypeFromBuffer(buffer)
+  const detectedMime = detected?.mime ?? null
+  if (!detectedMime || !ALLOWED_MIME_TYPES.has(detectedMime)) {
+    throw new Error(`File type not allowed: ${detectedMime ?? 'unknown'}`)
+  }
+
+  const ext = detected?.ext ?? file.name.split('.').pop() ?? 'bin'
+  const filename = `${Date.now()}-${crypto.randomBytes(6).toString('hex')}.${ext}`
+  const filePath = `${userId}/${incidentId}/${stage}/${filename}`
+
+  const hash = await computeHashFromBuffer(buffer)
+
+  const fullPath = path.join(evidenceDir(), filePath)
+  fs.mkdirSync(path.dirname(fullPath), { recursive: true })
+  fs.writeFileSync(fullPath, Buffer.from(buffer))
+
+  const publicUrl = getEvidenceUrl(filePath)
+
+  return { path: filePath, publicUrl, hash }
+}
+
+async function computeHashFromBuffer(buffer: ArrayBuffer): Promise<string> {
+  const hashBuffer = await crypto.subtle.digest('SHA-256', buffer)
+  return Array.from(new Uint8Array(hashBuffer))
+    .map(b => b.toString(16).padStart(2, '0'))
+    .join('')
+}