fix: file manager incorrectly decoding/encoding when editing files (made base64/utf8 dependent)

src/backend/ssh/file-manager.ts

@@ -343,6 +343,27 @@ function getMimeType(fileName: string): string {
   return mimeTypes[ext || ""] || "application/octet-stream";
 }
 
+function detectBinary(buffer: Buffer): boolean {
+  if (buffer.length === 0) return false;
+
+  const sampleSize = Math.min(buffer.length, 8192);
+  let nullBytes = 0;
+
+  for (let i = 0; i < sampleSize; i++) {
+    const byte = buffer[i];
+
+    if (byte === 0) {
+      nullBytes++;
+    }
+
+    if (byte < 32 && byte !== 9 && byte !== 10 && byte !== 13) {
+      if (++nullBytes > 1) return true;
+    }
+  }
+
+  return nullBytes / sampleSize > 0.01;
+}
+
 app.post("/ssh/file_manager/ssh/connect", async (req, res) => {
   const {
     sessionId,
@@ -1368,11 +1389,11 @@ app.get("/ssh/file_manager/ssh/readFile", (req, res) => {
             return res.status(500).json({ error: err.message });
           }
 
-          let data = "";
+          let binaryData = Buffer.alloc(0);
           let errorData = "";
 
           stream.on("data", (chunk: Buffer) => {
-            data += chunk.toString();
+            binaryData = Buffer.concat([binaryData, chunk]);
           });
 
           stream.stderr.on("data", (chunk: Buffer) => {
@@ -1396,7 +1417,23 @@ app.get("/ssh/file_manager/ssh/readFile", (req, res) => {
               });
             }
 
-            res.json({ content: data, path: filePath });
+            const isBinary = detectBinary(binaryData);
+
+            if (isBinary) {
+              const base64Content = binaryData.toString("base64");
+              res.json({
+                content: base64Content,
+                path: filePath,
+                encoding: "base64",
+              });
+            } else {
+              const textContent = binaryData.toString("utf8");
+              res.json({
+                content: textContent,
+                path: filePath,
+                encoding: "utf8",
+              });
+            }
           });
         });
       });
@@ -1440,7 +1477,16 @@ app.post("/ssh/file_manager/ssh/writeFile", async (req, res) => {
         let fileBuffer;
         try {
           if (typeof content === "string") {
-            fileBuffer = Buffer.from(content, "base64");
+            try {
+              const testBuffer = Buffer.from(content, "base64");
+              if (testBuffer.toString("base64") === content) {
+                fileBuffer = testBuffer;
+              } else {
+                fileBuffer = Buffer.from(content, "utf8");
+              }
+            } catch {
+              fileBuffer = Buffer.from(content, "utf8");
+            }
           } else if (Buffer.isBuffer(content)) {
             fileBuffer = content;
           } else {

src/ui/desktop/apps/features/file-manager/components/FileViewer.tsx

@@ -333,13 +333,7 @@ export function FileViewer({
     const ext = fileName.split(".").pop()?.toLowerCase() || "";
 
     if (ext === "svg") {
-      try {
-        const base64 = btoa(unescape(encodeURIComponent(content)));
-        return `data:image/svg+xml;base64,${base64}`;
-      } catch (e) {
-        console.error("Failed to encode SVG:", e);
-        return "";
-      }
+      return `data:image/svg+xml;base64,${content}`;
     }
 
     return `data:image/*;base64,${content}`;

src/ui/desktop/apps/features/file-manager/components/FileWindow.tsx

@@ -47,6 +47,22 @@ interface FileWindowProps {
   onFileNotFound?: (file: FileItem) => void;
 }
 
+function isDisplayableText(str: string): boolean {
+  let printable = 0;
+  for (let i = 0; i < Math.min(str.length, 1000); i++) {
+    const code = str.charCodeAt(i);
+    if (
+      (code >= 32 && code <= 126) ||
+      code === 9 ||
+      code === 10 ||
+      code === 13
+    ) {
+      printable++;
+    }
+  }
+  return printable / Math.min(str.length, 1000) > 0.85;
+}
+
 export function FileWindow({
   windowId,
   file,
@@ -106,7 +122,19 @@ export function FileWindow({
         await ensureSSHConnection();
 
         const response = await readSSHFile(sshSessionId, file.path);
-        const fileContent = response.content || "";
+        let fileContent = response.content || "";
+
+        if (response.encoding === "base64") {
+          try {
+            const decoded = atob(fileContent);
+            if (isDisplayableText(decoded)) {
+              fileContent = decoded;
+            }
+          } catch (err) {
+            console.error("Failed to decode base64 content:", err);
+          }
+        }
+
         setContent(fileContent);
         setPendingContent(fileContent);
 

src/ui/main-axios.ts

@@ -1421,7 +1421,11 @@ export async function identifySSHSymlink(
 export async function readSSHFile(
   sessionId: string,
   path: string,
-): Promise<{ content: string; path: string }> {
+): Promise<{
+  content: string;
+  path: string;
+  encoding?: "base64" | "utf8";
+}> {
   try {
     const response = await fileManagerApi.get("/ssh/readFile", {
       params: { sessionId, path },