diff --git a/app/api/upload/check/route.ts b/app/api/upload/check/route.ts
index 85140de..868b282 100644
--- a/app/api/upload/check/route.ts
+++ b/app/api/upload/check/route.ts
@@ -4,8 +4,7 @@ import { getRemoteFolder } from '@/lib/github'
 import { classifyFileChanges } from '@/lib/diff-files'
 import { getModelFolderPath } from '@/lib/model-paths'
 import { ensurePreparedStagingAssets } from '@/lib/upload-staging'
-import { parseStagingRequestBody } from '@/lib/upload-request'
-import { getErrorMessage } from '@/lib/guards'
+import { readStagingRequestBody, uploadErrorResponse } from '@/lib/upload-request'
 import type { FileDiff } from '@/lib/types'
 
 export const runtime = 'nodejs'
@@ -22,15 +21,13 @@ export async function POST(req: NextRequest) {
   let stagingId: string
 
   try {
-    const body: unknown = await req.json()
-    stagingId = parseStagingRequestBody(body).stagingId
+    stagingId = (await readStagingRequestBody(req)).stagingId
   } catch (err) {
-    const message = getErrorMessage(err)
-    return NextResponse.json({ success: false, error: message }, { status: 400 })
+    return uploadErrorResponse(err, 400)
   }
 
   try {
-    const { folderName, filesToPush } = await ensurePreparedStagingAssets(stagingId)
+    const { folderName, filesToPush, deliveryMode, compressionError } = await ensurePreparedStagingAssets(stagingId)
     const folderPath = getModelFolderPath(folderName)
     const { exists, files } = await getRemoteFolder(folderPath)
 
@@ -53,12 +50,18 @@ export async function POST(req: NextRequest) {
         exists: true,
         path: folderPath,
         diffs,
+        deliveryMode,
+        compressionError,
       })
     }
 
-    return NextResponse.json({ success: true, exists: false })
+    return NextResponse.json({
+      success: true,
+      exists: false,
+      deliveryMode,
+      compressionError,
+    })
   } catch (err) {
-    const message = getErrorMessage(err)
-    return NextResponse.json({ success: false, error: message }, { status: 500 })
+    return uploadErrorResponse(err, 500)
   }
 }
diff --git a/app/api/upload/drive/route.ts b/app/api/upload/drive/route.ts
index 61c232d..4da08d5 100644
--- a/app/api/upload/drive/route.ts
+++ b/app/api/upload/drive/route.ts
@@ -8,7 +8,12 @@ import {
   findNextVersion,
 } from '@/lib/nextcloud'
 import { acquireUploadLock, releaseUploadLock } from '@/lib/upload-lock'
-import { parseDriveRequestBody } from '@/lib/upload-request'
+import {
+  readDriveRequestBody,
+  uploadErrorMessageResponse,
+  uploadErrorResponse,
+  uploadLockConflictResponse,
+} from '@/lib/upload-request'
 import { getErrorMessage } from '@/lib/guards'
 import type { DriveAction } from '@/lib/types'
 
@@ -20,9 +25,9 @@ export async function POST(req: NextRequest) {
   if (authError) return authError
 
   if (!process.env.NEXTCLOUD_URL || !process.env.NEXTCLOUD_SHARE_TOKEN) {
-    return NextResponse.json(
-      { success: false, error: 'Nextcloud non configure sur le serveur (NEXTCLOUD_URL, NEXTCLOUD_SHARE_TOKEN)' },
-      { status: 500 },
+    return uploadErrorMessageResponse(
+      'Nextcloud non configure sur le serveur (NEXTCLOUD_URL, NEXTCLOUD_SHARE_TOKEN)',
+      500,
     )
   }
 
@@ -31,23 +36,18 @@ export async function POST(req: NextRequest) {
   let action: DriveAction
 
   try {
-    const body: unknown = await req.json()
-    const parsedBody = parseDriveRequestBody(body)
+    const parsedBody = await readDriveRequestBody(req)
     action = parsedBody.action
     const stagingId = parsedBody.stagingId
     const staged = await readStagedOriginalFiles(stagingId)
     folderName = staged.folderName
     parsedFiles = staged.files
   } catch (err) {
-    const message = getErrorMessage(err)
-    return NextResponse.json({ success: false, error: message }, { status: 400 })
+    return uploadErrorResponse(err, 400)
   }
 
   if (!acquireUploadLock(folderName)) {
-    return NextResponse.json(
-      { success: false, error: 'Un upload est deja en cours pour ce dossier. Patientez quelques secondes.' },
-      { status: 409 },
-    )
+    return uploadLockConflictResponse()
   }
 
   const basePath = process.env.NEXTCLOUD_BASE_PATH || 'Models'
@@ -79,10 +79,7 @@ export async function POST(req: NextRequest) {
     })
   } catch (err) {
     const message = getErrorMessage(err, 'Erreur Nextcloud inconnue')
-    return NextResponse.json(
-      { success: false, error: `Drive echoue: ${message}` },
-      { status: 500 },
-    )
+    return uploadErrorMessageResponse(`Drive echoue: ${message}`, 500)
   } finally {
     releaseUploadLock(folderName)
   }
diff --git a/app/api/upload/git/route.ts b/app/api/upload/git/route.ts
index f663f36..bd0583a 100644
--- a/app/api/upload/git/route.ts
+++ b/app/api/upload/git/route.ts
@@ -6,12 +6,26 @@ import { classifyFileChanges } from '@/lib/diff-files'
 import { getModelFolderPath } from '@/lib/model-paths'
 import { cleanupStagingUpload, ensurePreparedStagingAssets, readStagedManifest } from '@/lib/upload-staging'
 import { acquireUploadLock, releaseUploadLock } from '@/lib/upload-lock'
-import { parseStagingRequestBody } from '@/lib/upload-request'
+import {
+  readStagingRequestBody,
+  uploadErrorMessageResponse,
+  uploadErrorResponse,
+  uploadLockConflictResponse,
+} from '@/lib/upload-request'
 import { getErrorMessage } from '@/lib/guards'
 
 export const runtime = 'nodejs'
 export const dynamic = 'force-dynamic'
 
+async function cleanupCompletedStagingUpload(stagingId: string) {
+  await cleanupStagingUpload(stagingId).catch((err) => {
+    console.warn('[WARN] Git upload -> staging cleanup failed', {
+      stagingId,
+      error: getErrorMessage(err),
+    })
+  })
+}
+
 /**
  * POST /api/upload/git
  * Upload prepared files and push to GitHub via Octokit.
@@ -24,20 +38,15 @@ export async function POST(req: NextRequest) {
   let stagingId: string
 
   try {
-    const body: unknown = await req.json()
-    stagingId = parseStagingRequestBody(body).stagingId
+    stagingId = (await readStagingRequestBody(req)).stagingId
     const manifest = await readStagedManifest(stagingId)
     folderName = manifest.folderName
   } catch (err) {
-    const message = getErrorMessage(err)
-    return NextResponse.json({ success: false, error: message }, { status: 400 })
+    return uploadErrorResponse(err, 400)
   }
 
   if (!acquireUploadLock(folderName)) {
-    return NextResponse.json(
-      { success: false, error: 'Un upload est deja en cours pour ce dossier. Patientez quelques secondes.' },
-      { status: 409 },
-    )
+    return uploadLockConflictResponse()
   }
 
   try {
@@ -45,6 +54,7 @@ export async function POST(req: NextRequest) {
       filesToPush,
       modelFilename,
       compressed,
+      deliveryMode,
       compressionError,
       assetSummaries,
     } = await ensurePreparedStagingAssets(stagingId)
@@ -59,12 +69,13 @@ export async function POST(req: NextRequest) {
       classifyFileChanges(filesToPush, remoteFileMap, folderPath)
 
     if (changedFilesToPush.length === 0 && deletePaths.length === 0) {
-      await cleanupStagingUpload(stagingId).catch(() => {})
+      await cleanupCompletedStagingUpload(stagingId)
       return NextResponse.json({
         success: true,
         folderName,
         filesCount: 0,
         compressed,
+        deliveryMode,
         compressionError: compressionError || undefined,
         message: 'Aucun fichier modifie — rien a envoyer.',
       })
@@ -79,26 +90,22 @@ export async function POST(req: NextRequest) {
       deletedFileNames,
     )
 
-    try {
-      const { commitUrl } = await pushAllToGitHub(changedFilesToPush, deletePaths, commitMessage)
-      await cleanupStagingUpload(stagingId).catch(() => {})
+    const { commitUrl } = await pushAllToGitHub(changedFilesToPush, deletePaths, commitMessage)
+    await cleanupCompletedStagingUpload(stagingId)
 
-      return NextResponse.json({
-        success: true,
-        folderName,
-        filesCount: changedFilesToPush.length,
-        compressed,
-        compressionError: compressionError || undefined,
-        message: `${changedFilesToPush.length} fichier(s) modifie(s) envoye(s) sur GitHub en un seul commit.`,
-        commitUrl,
-      })
-    } catch (err) {
-      const message = getErrorMessage(err, 'Erreur GitHub inconnue')
-      return NextResponse.json(
-        { success: false, error: `Push GitHub echoue: ${message}` },
-        { status: 500 },
-      )
-    }
+    return NextResponse.json({
+      success: true,
+      folderName,
+      filesCount: changedFilesToPush.length,
+      compressed,
+      deliveryMode,
+      compressionError: compressionError || undefined,
+      message: `${changedFilesToPush.length} fichier(s) modifie(s) envoye(s) sur GitHub en un seul commit.`,
+      commitUrl,
+    })
+  } catch (err) {
+    const message = getErrorMessage(err, 'Erreur GitHub inconnue')
+    return uploadErrorMessageResponse(`Upload GitHub echoue: ${message}`, 500)
   } finally {
     releaseUploadLock(folderName)
   }
diff --git a/app/api/upload/stage/route.ts b/app/api/upload/stage/route.ts
index 9e12b9e..68d8179 100644
--- a/app/api/upload/stage/route.ts
+++ b/app/api/upload/stage/route.ts
@@ -2,7 +2,7 @@ import { NextRequest, NextResponse } from 'next/server'
 import { validateUploadSecret } from '@/lib/auth'
 import { parseMultiUpload } from '@/lib/parse-upload'
 import { createStagingUpload } from '@/lib/upload-staging'
-import { getErrorMessage } from '@/lib/guards'
+import { uploadErrorResponse } from '@/lib/upload-request'
 
 export const runtime = 'nodejs'
 export const dynamic = 'force-dynamic'
@@ -16,7 +16,6 @@ export async function POST(req: NextRequest) {
     const staged = await createStagingUpload(parsed.folderName, parsed.files, parsed.gitModelMode)
     return NextResponse.json({ success: true, ...staged })
   } catch (err) {
-    const message = getErrorMessage(err)
-    return NextResponse.json({ success: false, error: message }, { status: 400 })
+    return uploadErrorResponse(err, 400)
   }
 }
diff --git a/components/ModelViewer.tsx b/components/ModelViewer.tsx
index 50f599c..18d33dc 100644
--- a/components/ModelViewer.tsx
+++ b/components/ModelViewer.tsx
@@ -1,6 +1,7 @@
 'use client'
 
-import { useEffect, useState } from 'react'
+import { Component, useEffect, useState } from 'react'
+import type { ComponentType, ReactNode } from 'react'
 import type { ModelStats } from './SceneViewer'
 
 interface ModelViewerProps {
@@ -10,10 +11,51 @@ interface ModelViewerProps {
   size: string
 }
 
+function getPreviewErrorMessage(error: unknown) {
+  return error instanceof Error ? error.message : 'Erreur preview inconnue'
+}
+
+function PreviewFallback({ message }: { message?: string }) {
+  return (
+    <div className="flex h-full w-full items-center justify-center px-6 text-center">
+      <div className="max-w-sm space-y-2">
+        <p className="text-sm font-medium text-gray-300">Preview 3D indisponible pour ce modele.</p>
+        <p className="text-xs text-gray-500">
+          L&apos;upload reste possible. {message ? `Detail technique : ${message}` : ''}
+        </p>
+      </div>
+    </div>
+  )
+}
+
+class PreviewErrorBoundary extends Component<
+  { children: ReactNode },
+  { message: string | null }
+> {
+  state = { message: null }
+
+  static getDerivedStateFromError(error: unknown) {
+    return { message: getPreviewErrorMessage(error) }
+  }
+
+  componentDidCatch(error: unknown) {
+    console.error('[ERROR] Preview 3D indisponible', error)
+  }
+
+  render() {
+    if (this.state.message) {
+      return <PreviewFallback message={this.state.message} />
+    }
+
+    return this.props.children
+  }
+}
+
 export default function ModelViewer({ url, assetUrls, filename, size }: ModelViewerProps) {
   const canPreview = filename.toLowerCase().endsWith('.gltf')
   const [stats, setStats] = useState<ModelStats | null>(null)
-  const [Scene, setScene] = useState<React.ComponentType<{
+  const [sceneError, setSceneError] = useState<string | null>(null)
+  const [Scene, setScene] = useState<ComponentType<{
     url: string
     assetUrls: Record<string, string>
     onStatsReady: (stats: ModelStats) => void
@@ -23,13 +65,19 @@ export default function ModelViewer({ url, assetUrls, filename, size }: ModelVie
     if (!canPreview) return
 
     let cancel = false
+    setSceneError(null)
+    setStats(null)
 
-    import('./SceneViewer').then((mod) => {
-      if (!cancel) setScene(() => mod.default)
-    })
+    import('./SceneViewer')
+      .then((mod) => {
+        if (!cancel) setScene(() => mod.default)
+      })
+      .catch((error: unknown) => {
+        if (!cancel) setSceneError(getPreviewErrorMessage(error))
+      })
 
     return () => { cancel = true }
-  }, [canPreview])
+  }, [canPreview, url])
 
   if (!canPreview) {
     return (
@@ -87,7 +135,13 @@ export default function ModelViewer({ url, assetUrls, filename, size }: ModelVie
           </span>
         </div>
       )}
-      <Scene url={url} assetUrls={assetUrls} onStatsReady={setStats} />
+      {sceneError ? (
+        <PreviewFallback message={sceneError} />
+      ) : (
+        <PreviewErrorBoundary key={url}>
+          <Scene url={url} assetUrls={assetUrls} onStatsReady={setStats} />
+        </PreviewErrorBoundary>
+      )}
     </div>
   )
 }
diff --git a/components/SceneViewer.tsx b/components/SceneViewer.tsx
index 5b99e20..158a358 100644
--- a/components/SceneViewer.tsx
+++ b/components/SceneViewer.tsx
@@ -93,7 +93,7 @@ function supportsAlphaMap(material: Material): material is AlphaMapMaterial {
   return 'alphaMap' in material
 }
 
-function isAlphaImageSource(image: object | null | undefined): image is AlphaImageSource {
+function isAlphaImageSource(image: unknown): image is AlphaImageSource {
   return image instanceof HTMLImageElement
     || image instanceof HTMLCanvasElement
     || (typeof ImageBitmap !== 'undefined' && image instanceof ImageBitmap)
@@ -103,7 +103,7 @@ function createAlphaMapTexture(texture: Texture) {
   const cachedTexture = alphaMapTextureCache.get(texture)
   if (cachedTexture) return cachedTexture
 
-  const image = texture.image as object | null | undefined
+  const image = texture.image
 
   if (!isAlphaImageSource(image)) {
     texture.flipY = false
@@ -243,7 +243,7 @@ function Model({
     loader.manager.setURLModifier((requestedUrl) => resolveAssetUrl(requestedUrl, assetUrls))
   })
   const opacityMapEntries = getOpacityMapEntries(assetUrls)
-  const opacityMaps = useLoader(TextureLoader, opacityMapEntries.map((entry) => entry.url)) as Texture[]
+  const opacityMaps = useLoader(TextureLoader, opacityMapEntries.map((entry) => entry.url))
 
   useEffect(() => {
     onStatsReady(getModelStats(scene, assetUrls))
diff --git a/components/upload/DriveStatusLine.tsx b/components/upload/DriveStatusLine.tsx
index 544b25b..908a84e 100644
--- a/components/upload/DriveStatusLine.tsx
+++ b/components/upload/DriveStatusLine.tsx
@@ -1,8 +1,8 @@
 import { SpinnerIcon, XIcon, WarningIcon } from '@/components/ui/icons'
-import type { FolderEntry } from '@/lib/client-types'
+import type { DriveStatus } from '@/lib/client-types'
 
 interface DriveStatusLineProps {
-  driveStatus: NonNullable<FolderEntry['driveStatus']>
+  driveStatus: DriveStatus
   driveError?: string
 }
 
diff --git a/components/upload/FolderCard.tsx b/components/upload/FolderCard.tsx
index e63ab0e..1452f4c 100644
--- a/components/upload/FolderCard.tsx
+++ b/components/upload/FolderCard.tsx
@@ -1,7 +1,7 @@
 import dynamic from 'next/dynamic'
 import type { FolderEntry } from '@/lib/client-types'
 import { formatBytes } from '@/lib/format-bytes'
-import { SpinnerIcon, CheckIcon, XIcon, ChevronIcon } from '@/components/ui/icons'
+import { SpinnerIcon, CheckIcon, XIcon, ChevronIcon, WarningIcon } from '@/components/ui/icons'
 import DriveStatusLine from './DriveStatusLine'
 import WarningBanner from './WarningBanner'
 
@@ -63,6 +63,13 @@ export default function FolderCard({ entry, index, onToggleViewer, onRemove }: F
             <DriveStatusLine driveStatus={entry.driveStatus} driveError={entry.driveError} />
           )}
 
+          {entry.uploadWarning && (
+            <div className="mt-1.5 flex items-start gap-1.5 text-xs text-yellow-400">
+              <WarningIcon className="mt-0.5 h-3.5 w-3.5 shrink-0" />
+              <span className="line-clamp-2">{entry.uploadWarning}</span>
+            </div>
+          )}
+
           {entry.status === 'uploading' && (
             <div className="mt-1.5 w-full h-1 bg-black-700 rounded-full overflow-hidden">
               <div
diff --git a/components/upload/FolderDropzone.tsx b/components/upload/FolderDropzone.tsx
index 9731a50..45a054d 100644
--- a/components/upload/FolderDropzone.tsx
+++ b/components/upload/FolderDropzone.tsx
@@ -1,6 +1,7 @@
 import { useRef, useState } from 'react'
 import type { FolderEntry } from '@/lib/client-types'
 import { validateFolder } from '@/lib/validate-folder'
+import { getErrorMessage } from '@/lib/guards'
 import { FolderIcon } from '@/components/ui/icons'
 
 function buildAssetUrls(model: File, supportFiles: File[]) {
@@ -156,8 +157,8 @@ export default function FolderDropzone({
       if (droppedFiles.length === 0) return
 
       await processFiles(droppedFiles)
-    } catch {
-      onError('Impossible de lire le dossier depose')
+    } catch (err) {
+      onError(`Impossible de lire le dossier depose: ${getErrorMessage(err)}`)
     }
   }
 
diff --git a/hooks/useUploadOrchestrator.ts b/hooks/useUploadOrchestrator.ts
index 5b1b3b3..47e9846 100644
--- a/hooks/useUploadOrchestrator.ts
+++ b/hooks/useUploadOrchestrator.ts
@@ -3,9 +3,13 @@
 import { useState, useRef, useCallback } from 'react'
 import { getErrorMessage } from '@/lib/guards'
 import type { FolderEntry } from '@/lib/client-types'
-import type { DriveAction, FileDiff, GitModelMode } from '@/lib/types'
+import type {
+  CheckUploadResult,
+  DriveAction,
+  FileDiff,
+  GitModelMode,
+} from '@/lib/types'
 import { checkFolderDiffs, stageUpload, uploadDrive, uploadGit } from '@/lib/upload-api'
-import type { CheckResult } from '@/lib/upload-api'
 
 type UploadLogDetails = Record<string, string | number | boolean | undefined>
 
@@ -62,7 +66,7 @@ export function useUploadOrchestrator({
   } | null>(null)
 
   const abortRef = useRef<AbortController | null>(null)
-  const checkResultRef = useRef<CheckResult>({ exists: false, diffs: [] })
+  const checkResultRef = useRef<CheckUploadResult>({ exists: false, diffs: [] })
   const uploadActionRef = useRef(false)
   const stagingIdRef = useRef<string | null>(null)
 
@@ -101,6 +105,7 @@ export function useUploadOrchestrator({
       status: gitResult.success ? 'success' : 'error',
       progress: gitResult.success ? 100 : 0,
       error: gitResult.success ? undefined : gitResult.error,
+      uploadWarning: gitResult.success ? gitResult.warning : undefined,
       filename: gitResult.filename,
     })
   }, [updateEntry])
@@ -135,6 +140,7 @@ export function useUploadOrchestrator({
           status: 'uploading',
           progress: 1,
           error: undefined,
+          uploadWarning: undefined,
           driveStatus: 'uploading',
           driveError: undefined,
         })
@@ -221,7 +227,7 @@ export function useUploadOrchestrator({
         folderName: folder.folderName,
         stagingId: staged.stagingId,
       })
-      let check: CheckResult
+      let check: CheckUploadResult
 
       try {
         check = await checkFolderDiffs(
@@ -238,6 +244,7 @@ export function useUploadOrchestrator({
       }
 
       checkResultRef.current = check
+      updateEntry(0, { uploadWarning: check.warning })
 
       if (check.exists) {
         if (check.diffs.length === 0) {
@@ -289,6 +296,7 @@ export function useUploadOrchestrator({
           status: 'uploading',
           progress: 0,
           error: undefined,
+          uploadWarning: undefined,
           driveStatus: 'skipped',
         })
 
diff --git a/lib/client-types.ts b/lib/client-types.ts
index 73be2d6..eda1f5f 100644
--- a/lib/client-types.ts
+++ b/lib/client-types.ts
@@ -1,11 +1,11 @@
-type FileStatus = 'pending' | 'uploading' | 'success' | 'error'
+export type FileStatus = 'pending' | 'uploading' | 'success' | 'error'
 
 export interface TextureFile {
   name: string
   file: File
 }
 
-type DriveStatus = 'pending' | 'uploading' | 'success' | 'error' | 'skipped'
+export type DriveStatus = 'pending' | 'uploading' | 'success' | 'error' | 'skipped'
 
 export interface FolderEntry {
   folderName: string
@@ -14,6 +14,7 @@ export interface FolderEntry {
   status: FileStatus
   progress: number
   error?: string
+  uploadWarning?: string
   filename?: string
   modelUrl?: string
   assetUrls: Record<string, string>
diff --git a/lib/github.ts b/lib/github.ts
index dd4ab1f..cdda391 100644
--- a/lib/github.ts
+++ b/lib/github.ts
@@ -19,17 +19,33 @@ function getOctokit(): Octokit {
 }
 
 function parseRepoUrl(): { owner: string; repo: string } {
-  const url = process.env.GIT_REPO_URL
+  const url = process.env.GIT_REPO_URL?.trim()
   if (!url) throw new Error('GIT_REPO_URL non configure')
 
-  const httpsMatch = url.match(/github\.com\/([^/]+)\/([^/.]+)/)
-  const sshMatch = url.match(/github\.com:([^/]+)\/([^/.]+)/)
-  const shortMatch = url.match(/^([^/]+)\/([^/]+)$/)
+  const cleanRepoName = (repo: string) => repo.replace(/\/+$/, '').replace(/\.git$/, '')
+  const shortMatch = url.match(/^([^/\s:]+)\/([^/\s]+)$/)
+  if (shortMatch) {
+    return { owner: shortMatch[1], repo: cleanRepoName(shortMatch[2]) }
+  }
 
-  const match = httpsMatch || sshMatch || shortMatch
-  if (!match) throw new Error(`Format GIT_REPO_URL invalide: "${url}"`)
+  const sshMatch = url.match(/github\.com:([^/\s]+)\/(.+)$/)
+  if (sshMatch) {
+    return { owner: sshMatch[1], repo: cleanRepoName(sshMatch[2]) }
+  }
 
-  return { owner: match[1], repo: match[2] }
+  if (URL.canParse(url)) {
+    const parsed = new URL(url)
+    const pathParts = parsed.pathname
+      .replace(/^\/+|\/+$/g, '')
+      .split('/')
+      .filter(Boolean)
+
+    if (parsed.hostname === 'github.com' && pathParts.length >= 2) {
+      return { owner: pathParts[0], repo: cleanRepoName(pathParts[1]) }
+    }
+  }
+
+  throw new Error(`Format GIT_REPO_URL invalide: "${url}"`)
 }
 
 function isLfsFile(filePath: string): boolean {
@@ -73,12 +89,17 @@ interface LfsObject {
   contentBase64: string
 }
 
+interface LfsBatchAction {
+  href: string
+  header?: Record<string, string>
+}
+
 interface LfsBatchObject {
   oid: string
   size: number
   actions?: {
-    upload?: { href: string; header?: Record<string, string> }
-    verify?: { href: string; header?: Record<string, string> }
+    upload?: LfsBatchAction
+    verify?: LfsBatchAction
   }
   error?: { code: number; message: string }
 }
@@ -87,7 +108,7 @@ function isStringRecord(value: unknown): value is Record<string, string> {
   return isRecord(value) && Object.values(value).every((entry) => typeof entry === 'string')
 }
 
-function parseLfsAction(value: unknown) {
+function parseLfsAction(value: unknown): LfsBatchAction | undefined {
   if (!isRecord(value) || typeof value.href !== 'string') return undefined
   return {
     href: value.href,
diff --git a/lib/parse-upload.ts b/lib/parse-upload.ts
index b2e58fb..7addb26 100644
--- a/lib/parse-upload.ts
+++ b/lib/parse-upload.ts
@@ -19,8 +19,16 @@ function parseGitModelMode(value: FormDataEntryValue | null): GitModelMode {
 export async function parseMultiUpload(req: NextRequest): Promise<ParsedUpload> {
   const formData = await req.formData()
   const folderValue = formData.get('folderName')
-  const folderName = typeof folderValue === 'string' ? folderValue.trim() || 'assets' : 'assets'
+  if (typeof folderValue !== 'string' || folderValue.trim() === '') {
+    throw new Error('Nom de dossier manquant')
+  }
+
+  const folderName = folderValue.trim()
   const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
+  if (!safeFolderName) {
+    throw new Error('Nom de dossier invalide')
+  }
+
   const gitModelMode = parseGitModelMode(formData.get('gitModelMode'))
 
   const rawFiles = formData.getAll('files')
diff --git a/lib/prepare-git-assets.ts b/lib/prepare-git-assets.ts
index 6a96a1e..bb6c1e1 100644
--- a/lib/prepare-git-assets.ts
+++ b/lib/prepare-git-assets.ts
@@ -7,6 +7,7 @@ import { compressTextureBuffer } from '@/lib/texture-compression'
 import { classifyAssetCategory } from '@/lib/asset-classification'
 import { normalizeTextureFilename } from '@/lib/asset-naming'
 import { TEXTURE_EXTENSIONS, TMP_DIR } from '@/lib/constants'
+import { getErrorMessage, isRecord } from '@/lib/guards'
 import { getModelAssetPath } from '@/lib/model-paths'
 import type { GitModelMode, ParsedFile, PreparedAssetSummary, PreparedGitAssetsResult, PushFile } from '@/lib/types'
 
@@ -18,6 +19,30 @@ interface PrepareGitAssetsParams {
 
 type JsonValue = string | number | boolean | null | JsonValue[] | { [key: string]: JsonValue }
 
+function isJsonValue(value: unknown): value is JsonValue {
+  if (value === null) return true
+
+  if (typeof value === 'string' || typeof value === 'number' || typeof value === 'boolean') {
+    return true
+  }
+
+  if (Array.isArray(value)) {
+    return value.every(isJsonValue)
+  }
+
+  return isRecord(value) && Object.values(value).every(isJsonValue)
+}
+
+function parseJsonValue(content: string) {
+  const parsed: unknown = JSON.parse(content)
+
+  if (!isJsonValue(parsed)) {
+    throw new Error('model.gltf contient un JSON invalide')
+  }
+
+  return parsed
+}
+
 function getTextureFilenameMap(parsedFiles: ParsedFile[]) {
   const filenameMap = new Map<string, string>()
   const normalizedGroups = new Map<string, Array<{ original: string; normalized: string }>>()
@@ -75,7 +100,7 @@ function rewriteGltfUris(value: JsonValue, filenameMap: Map<string, string>): Js
 function prepareModelBuffer(buffer: Buffer, filenameMap: Map<string, string>) {
   if (filenameMap.size === 0) return buffer
 
-  const parsed = JSON.parse(buffer.toString('utf-8')) as JsonValue
+  const parsed = parseJsonValue(buffer.toString('utf-8'))
   return Buffer.from(JSON.stringify(rewriteGltfUris(parsed, filenameMap), null, 2), 'utf-8')
 }
 
@@ -130,7 +155,14 @@ async function prepareSeparateFiles(
     })
   }
 
-  return { filesToPush, modelFilename, assetSummaries, compressed, compressionError }
+  return {
+    filesToPush,
+    modelFilename,
+    assetSummaries,
+    compressed,
+    compressionError,
+    deliveryMode: 'keep-gltf' as const,
+  }
 }
 
 async function prepareDracoGlb(
@@ -160,22 +192,35 @@ async function prepareDracoGlb(
       await writeFile(join(tmpFolder, filename), content)
     }
 
-    const result = await compressWithBlender(inputModelPath, outputModelPath)
-    if (!result.success || !existsSync(outputModelPath)) {
-      throw new Error(result.error || 'Compression Blender echouee')
-    }
+    try {
+      const result = await compressWithBlender(inputModelPath, outputModelPath)
+      if (!result.success || !existsSync(outputModelPath)) {
+        throw new Error(result.error || 'Compression Blender echouee')
+      }
 
-    const content = await readFile(outputModelPath)
-    const modelFilename = 'model.glb'
+      const content = await readFile(outputModelPath)
+      const modelFilename = 'model.glb'
 
-    return {
-      filesToPush: [{
-        path: getModelAssetPath(folderName, modelFilename),
-        contentBase64: content.toString('base64'),
-      }],
-      modelFilename,
-      assetSummaries: [{ filename: modelFilename, kind: 'model', compressed: true }],
-      compressed: true,
+      return {
+        filesToPush: [{
+          path: getModelAssetPath(folderName, modelFilename),
+          contentBase64: content.toString('base64'),
+        }],
+        modelFilename,
+        assetSummaries: [{ filename: modelFilename, kind: 'model', compressed: true }],
+        compressed: true,
+        deliveryMode: 'draco-glb',
+      }
+    } catch (err) {
+      const fallback = await prepareSeparateFiles(folderName, parsedFiles, textureFilenameMap)
+      const message = getErrorMessage(err, 'Compression Blender echouee')
+
+      return {
+        ...fallback,
+        compressionError: fallback.compressionError
+          ? `${message}. ${fallback.compressionError}`
+          : message,
+      }
     }
   } finally {
     await rm(tmpFolder, { recursive: true, force: true }).catch(() => {})
diff --git a/lib/types.ts b/lib/types.ts
index 53fee88..7e4e8fa 100644
--- a/lib/types.ts
+++ b/lib/types.ts
@@ -15,11 +15,13 @@ export type DriveAction = 'new' | 'replace'
 
 export type FileChange = 'new' | 'changed' | 'unchanged'
 
+export type FileDiffStatus = 'changed' | 'new' | 'deleted'
+
 export type AssetCategory = 'color' | 'diffuse' | 'roughness' | 'normal' | 'metalness' | 'height' | 'opacity' | 'orm' | 'ao' | 'assets'
 
 export interface FileDiff {
   name: string
-  status: 'changed' | 'new' | 'deleted'
+  status: FileDiffStatus
 }
 
 export interface RemoteFile {
@@ -40,11 +42,30 @@ export interface StagingUploadResult {
   filesCount: number
 }
 
+export interface CheckUploadResult {
+  exists: boolean
+  diffs: FileDiff[]
+  warning?: string
+}
+
+export interface DriveUploadResult {
+  success: boolean
+  error?: string
+}
+
+export interface GitUploadResult {
+  success: boolean
+  filename?: string
+  warning?: string
+  error?: string
+}
+
 export interface PreparedGitAssetsResult {
   filesToPush: PushFile[]
   modelFilename: string
   assetSummaries: PreparedAssetSummary[]
   compressed: boolean
+  deliveryMode: GitModelMode
   compressionError?: string
 }
 
diff --git a/lib/upload-api.ts b/lib/upload-api.ts
index 1a5fd4e..e8c7260 100644
--- a/lib/upload-api.ts
+++ b/lib/upload-api.ts
@@ -1,16 +1,46 @@
-import { isRecord } from './guards'
+import { getErrorMessage, isRecord } from './guards'
 import type { FolderEntry } from './client-types'
-import type { DriveAction, FileDiff, GitModelMode, StagingUploadResult } from './types'
+import type {
+  CheckUploadResult,
+  DriveAction,
+  DriveUploadResult,
+  FileDiff,
+  GitModelMode,
+  GitUploadResult,
+  StagingUploadResult,
+} from './types'
 
-export interface CheckResult {
-  exists: boolean
-  diffs: FileDiff[]
+interface CompressionWarningPayload {
+  compressionError?: unknown
 }
 
+interface SuccessfulUploadData extends CompressionWarningPayload {
+  success: true
+  exists?: unknown
+  diffs?: unknown
+  stagingId?: unknown
+  folderName?: unknown
+  filesCount?: unknown
+}
+
+type UploadJsonBody =
+  | { stagingId: string }
+  | { stagingId: string; action: DriveAction }
+
 function getApiError(data: unknown, fallback: string) {
   return isRecord(data) && typeof data.error === 'string' ? data.error : fallback
 }
 
+function getClientRequestError(err: unknown, label: string) {
+  return `${label}: ${getErrorMessage(err)}`
+}
+
+function getCompressionWarning(data: CompressionWarningPayload) {
+  if (typeof data.compressionError !== 'string') return undefined
+
+  return `Compression GLB impossible. Le modele a ete prepare en GLTF separe. Detail : ${data.compressionError}`
+}
+
 function getUploadJsonHeaders(secret: string) {
   return {
     'Content-Type': 'application/json',
@@ -18,10 +48,35 @@ function getUploadJsonHeaders(secret: string) {
   }
 }
 
+async function postUploadJson(
+  endpoint: string,
+  secret: string,
+  body: UploadJsonBody,
+  signal?: AbortSignal,
+) {
+  const res = await fetch(endpoint, {
+    method: 'POST',
+    headers: getUploadJsonHeaders(secret),
+    body: JSON.stringify(body),
+    signal,
+  })
+
+  const data: unknown = await res.json()
+  return { res, data }
+}
+
+function isSuccessfulUploadData(data: unknown): data is SuccessfulUploadData {
+  return isRecord(data) && data.success === true
+}
+
 function isAbortError(err: unknown) {
   return err instanceof DOMException && err.name === 'AbortError'
 }
 
+function getNetworkUploadError(err: unknown, label: string) {
+  return isAbortError(err) ? 'Upload annule' : getClientRequestError(err, label)
+}
+
 function isFileDiff(value: unknown): value is FileDiff {
   return isRecord(value)
     && typeof value.name === 'string'
@@ -50,27 +105,34 @@ export async function checkFolderDiffs(
   stagingId: string,
   secret: string,
   signal?: AbortSignal,
-): Promise<CheckResult> {
-  const res = await fetch('/api/upload/check', {
-    method: 'POST',
-    headers: getUploadJsonHeaders(secret),
-    body: JSON.stringify({ stagingId }),
-    signal,
-  })
-
-  const data: unknown = await res.json()
+): Promise<CheckUploadResult> {
+  const { res, data } = await postUploadJson('/api/upload/check', secret, { stagingId }, signal)
 
   if (!res.ok) {
     throw new Error(getApiError(data, `Erreur serveur (${res.status})`))
   }
 
-  if (!isRecord(data) || data.success !== true || data.exists !== true) {
-    return { exists: false, diffs: [] }
+  if (!isSuccessfulUploadData(data)) {
+    throw new Error('Reponse serveur invalide')
+  }
+
+  const warning = getCompressionWarning(data)
+
+  if (data.exists !== true) {
+    return {
+      exists: false,
+      diffs: [],
+      warning,
+    }
   }
 
   const diffs = Array.isArray(data.diffs) ? data.diffs.filter(isFileDiff) : []
 
-  return { exists: true, diffs }
+  return {
+    exists: true,
+    diffs,
+    warning,
+  }
 }
 
 export async function stageUpload(
@@ -89,7 +151,7 @@ export async function stageUpload(
 
   const data: unknown = await res.json()
 
-  if (!res.ok || !isRecord(data) || data.success !== true) {
+  if (!res.ok || !isSuccessfulUploadData(data)) {
     throw new Error(getApiError(data, `Erreur serveur (${res.status})`))
   }
 
@@ -109,24 +171,15 @@ export async function uploadDrive(
   secret: string,
   action: DriveAction,
   signal?: AbortSignal,
-): Promise<{ success: boolean; error?: string }> {
+): Promise<DriveUploadResult> {
   try {
-    const res = await fetch('/api/upload/drive', {
-      method: 'POST',
-      headers: getUploadJsonHeaders(secret),
-      body: JSON.stringify({ stagingId, action }),
-      signal,
-    })
-    const data: unknown = await res.json()
-    if (!res.ok || !isRecord(data) || data.success !== true) {
+    const { res, data } = await postUploadJson('/api/upload/drive', secret, { stagingId, action }, signal)
+    if (!res.ok || !isSuccessfulUploadData(data)) {
       return { success: false, error: getApiError(data, `Erreur serveur (${res.status})`) }
     }
     return { success: true }
   } catch (err) {
-    if (isAbortError(err)) {
-      return { success: false, error: 'Upload annule' }
-    }
-    return { success: false, error: 'Erreur reseau (Drive)' }
+    return { success: false, error: getNetworkUploadError(err, 'Erreur Drive') }
   }
 }
 
@@ -135,30 +188,25 @@ export async function uploadGit(
   secret: string,
   onProgress: (pct: number) => void,
   signal?: AbortSignal,
-): Promise<{ success: boolean; filename?: string; error?: string }> {
+): Promise<GitUploadResult> {
   onProgress(10)
 
   try {
-    const res = await fetch('/api/upload/git', {
-      method: 'POST',
-      headers: getUploadJsonHeaders(secret),
-      body: JSON.stringify({ stagingId }),
-      signal,
-    })
+    const { res, data } = await postUploadJson('/api/upload/git', secret, { stagingId }, signal)
 
     onProgress(80)
-    const data: unknown = await res.json()
 
-    if (!res.ok || !isRecord(data) || data.success !== true) {
+    if (!res.ok || !isSuccessfulUploadData(data)) {
       return { success: false, error: getApiError(data, `Erreur serveur (${res.status})`) }
     }
 
     onProgress(100)
-    return { success: true, filename: typeof data.folderName === 'string' ? data.folderName : undefined }
-  } catch (err) {
-    if (isAbortError(err)) {
-      return { success: false, error: 'Upload annule' }
+    return {
+      success: true,
+      filename: typeof data.folderName === 'string' ? data.folderName : undefined,
+      warning: getCompressionWarning(data),
     }
-    return { success: false, error: 'Erreur reseau' }
+  } catch (err) {
+    return { success: false, error: getNetworkUploadError(err, 'Erreur GitHub') }
   }
 }
diff --git a/lib/upload-request.ts b/lib/upload-request.ts
index 34f0846..0093f8c 100644
--- a/lib/upload-request.ts
+++ b/lib/upload-request.ts
@@ -1,4 +1,5 @@
-import { isRecord } from './guards'
+import { NextResponse } from 'next/server'
+import { getErrorMessage, isRecord } from './guards'
 import type { DriveAction } from './types'
 
 interface StagingRequestBody {
@@ -9,6 +10,21 @@ interface DriveRequestBody extends StagingRequestBody {
   action: DriveAction
 }
 
+const UPLOAD_LOCK_ERROR = 'Un upload est deja en cours pour ce dossier. Patientez quelques secondes.'
+
+export function uploadErrorResponse(error: unknown, status: number, fallback?: string) {
+  const message = getErrorMessage(error, fallback)
+  return NextResponse.json({ success: false, error: message }, { status })
+}
+
+export function uploadErrorMessageResponse(message: string, status: number) {
+  return NextResponse.json({ success: false, error: message }, { status })
+}
+
+export function uploadLockConflictResponse() {
+  return uploadErrorMessageResponse(UPLOAD_LOCK_ERROR, 409)
+}
+
 export function parseStagingRequestBody(value: unknown): StagingRequestBody {
   if (!isRecord(value) || typeof value.stagingId !== 'string' || value.stagingId.trim() === '') {
     throw new Error('stagingId manquant')
@@ -17,9 +33,22 @@ export function parseStagingRequestBody(value: unknown): StagingRequestBody {
   return { stagingId: value.stagingId }
 }
 
+export async function readStagingRequestBody(req: Request): Promise<StagingRequestBody> {
+  const body: unknown = await req.json()
+  return parseStagingRequestBody(body)
+}
+
 export function parseDriveRequestBody(value: unknown): DriveRequestBody {
   const { stagingId } = parseStagingRequestBody(value)
-  const action = isRecord(value) && value.action === 'replace' ? 'replace' : 'new'
 
-  return { stagingId, action }
+  if (!isRecord(value) || (value.action !== 'new' && value.action !== 'replace')) {
+    throw new Error('Action Drive invalide')
+  }
+
+  return { stagingId, action: value.action }
+}
+
+export async function readDriveRequestBody(req: Request): Promise<DriveRequestBody> {
+  const body: unknown = await req.json()
+  return parseDriveRequestBody(body)
 }
diff --git a/lib/upload-staging.ts b/lib/upload-staging.ts
index 6b76bc6..4627a4e 100644
--- a/lib/upload-staging.ts
+++ b/lib/upload-staging.ts
@@ -3,9 +3,11 @@ import { dirname, join } from 'path'
 import { mkdir, readdir, readFile, rm, writeFile } from 'fs/promises'
 import { existsSync } from 'fs'
 import { TMP_DIR } from '@/lib/constants'
+import { isRecord } from '@/lib/guards'
 import { getModelAssetPath } from '@/lib/model-paths'
 import { prepareGitAssets } from '@/lib/prepare-git-assets'
 import type {
+  AssetCategory,
   GitModelMode,
   ParsedFile,
   PreparedAssetSummary,
@@ -26,6 +28,7 @@ interface StagedOriginalFile {
 interface StagedPreparedData {
   modelFilename: string
   compressed: boolean
+  deliveryMode?: GitModelMode
   compressionError?: string
   assetSummaries: PreparedAssetSummary[]
 }
@@ -55,6 +58,69 @@ function getManifestPath(stagingId: string) {
   return join(getStageDir(stagingId), 'manifest.json')
 }
 
+function isGitModelMode(value: unknown): value is GitModelMode {
+  return value === 'draco-glb' || value === 'keep-gltf'
+}
+
+function isAssetCategory(value: unknown): value is AssetCategory {
+  return value === 'color'
+    || value === 'diffuse'
+    || value === 'roughness'
+    || value === 'normal'
+    || value === 'metalness'
+    || value === 'height'
+    || value === 'opacity'
+    || value === 'orm'
+    || value === 'ao'
+    || value === 'assets'
+}
+
+function isPreparedAssetSummary(value: unknown): value is PreparedAssetSummary {
+  return isRecord(value)
+    && typeof value.filename === 'string'
+    && (value.kind === 'model' || value.kind === 'texture' || value.kind === 'asset')
+    && (value.category === undefined || isAssetCategory(value.category))
+    && typeof value.compressed === 'boolean'
+}
+
+function isStagedOriginalFile(value: unknown): value is StagedOriginalFile {
+  return isRecord(value)
+    && typeof value.filename === 'string'
+    && typeof value.size === 'number'
+    && typeof value.isModel === 'boolean'
+}
+
+function isStagedPreparedData(value: unknown): value is StagedPreparedData {
+  return isRecord(value)
+    && typeof value.modelFilename === 'string'
+    && typeof value.compressed === 'boolean'
+    && (value.deliveryMode === undefined || isGitModelMode(value.deliveryMode))
+    && (value.compressionError === undefined || typeof value.compressionError === 'string')
+    && Array.isArray(value.assetSummaries)
+    && value.assetSummaries.every(isPreparedAssetSummary)
+}
+
+function isStagingManifest(value: unknown): value is StagingManifest {
+  return isRecord(value)
+    && typeof value.stagingId === 'string'
+    && typeof value.folderName === 'string'
+    && isGitModelMode(value.gitModelMode)
+    && typeof value.createdAt === 'number'
+    && Array.isArray(value.originals)
+    && value.originals.every(isStagedOriginalFile)
+    && (value.prepared === undefined || isStagedPreparedData(value.prepared))
+}
+
+function parseStagingManifest(content: string) {
+  const parsed: unknown = JSON.parse(content)
+
+  if (!isStagingManifest(parsed)) {
+    throw new Error('Manifest de staging invalide')
+  }
+
+  return parsed
+}
+
 async function ensureParentDir(filePath: string) {
   await mkdir(dirname(filePath), { recursive: true })
 }
@@ -126,7 +192,7 @@ export async function createStagingUpload(
 export async function readStagedManifest(stagingId: string): Promise<StagingManifest> {
   const manifestPath = getManifestPath(stagingId)
   const content = await readFile(manifestPath, 'utf-8')
-  return JSON.parse(content) as StagingManifest
+  return parseStagingManifest(content)
 }
 
 async function readOriginalParsedFiles(stagingId: string, manifest: StagingManifest): Promise<ParsedFile[]> {
@@ -179,6 +245,7 @@ export async function ensurePreparedStagingAssets(stagingId: string): Promise<Pr
     manifest.prepared = {
       modelFilename: prepared.modelFilename,
       compressed: prepared.compressed,
+      deliveryMode: prepared.deliveryMode,
       compressionError: prepared.compressionError,
       assetSummaries: prepared.assetSummaries,
     }
@@ -192,6 +259,7 @@ export async function ensurePreparedStagingAssets(stagingId: string): Promise<Pr
     modelFilename: manifest.prepared.modelFilename,
     assetSummaries: manifest.prepared.assetSummaries,
     compressed: manifest.prepared.compressed,
+    deliveryMode: manifest.prepared.deliveryMode ?? manifest.gitModelMode,
     compressionError: manifest.prepared.compressionError,
   }
 }
diff --git a/lib/validate-folder.ts b/lib/validate-folder.ts
index 7816a7d..fc5bbcf 100644
--- a/lib/validate-folder.ts
+++ b/lib/validate-folder.ts
@@ -6,22 +6,25 @@ import type { TextureFile } from '@/lib/client-types'
 const SUPPORT_FILE_EXT_ARRAY = [...TEXTURE_EXTENSIONS, ...ASSET_EXTENSIONS]
 
 interface GltfBufferReference {
-  uri?: unknown
+  uri?: string
 }
 
 interface GltfJson {
   buffers?: GltfBufferReference[]
 }
 
-/** Discriminated union: either valid (with model) or invalid (with errors). */
 type ValidationResult =
   | { ok: true; model: File; textures: TextureFile[]; warnings: string[] }
   | { ok: false; errors: string[] }
 
+function isGltfBufferReference(value: unknown): value is GltfBufferReference {
+  return isRecord(value) && (value.uri === undefined || typeof value.uri === 'string')
+}
+
 function isGltfJson(value: unknown): value is GltfJson {
   if (!isRecord(value)) return false
   if (value.buffers === undefined) return true
-  return Array.isArray(value.buffers) && value.buffers.every(isRecord)
+  return Array.isArray(value.buffers) && value.buffers.every(isGltfBufferReference)
 }
 
 function getReferencedBufferNames(gltf: GltfJson) {