Merge pull request #107 from delibae/fix/multi-file-pdf-preview

fix: resolve PDF preview to correct root file in multi-file LaTeX projects

apps/desktop/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@claude-prism/desktop",
-  "version": "1.1.1",
+  "version": "1.1.2",
   "private": true,
   "type": "module",
   "scripts": {

apps/desktop/src-tauri/tauri.conf.json

@@ -2,7 +2,7 @@
   "$schema": "https://raw.githubusercontent.com/nicegui-unofficial/nicegui-tauri-template/main/src-tauri/tauri.conf-v2-schema.json",
   "identifier": "com.claude-prism.desktop",
   "productName": "ClaudePrism",
-  "version": "1.1.1",
+  "version": "1.1.2",
   "build": {
     "beforeDevCommand": "pnpm dev",
     "beforeBuildCommand": "pnpm build",

apps/desktop/src/lib/latex-compiler.ts

@@ -5,6 +5,8 @@ import { createLogger } from "@/lib/debug/logger";
 const log = createLogger("latex");
 
 /** Resolve which file to compile and the root ID for caching.
+ *  resolveTexRoot now handles \documentclass detection and main.tex fallback,
+ *  so the only remaining fallback here is for projects with no .tex files.
  *  Returns `null` when the project has no compilable .tex file. */
 export function resolveCompileTarget(
   activeFileId: string,
@@ -15,19 +17,11 @@ export function resolveCompileTarget(
   if (rootEntry?.type === "tex") {
     return { rootId, targetPath: rootEntry.relativePath };
   }
-  // Fallback: look for any well-known root tex file
-  const fallback = files.find(
-    (f) => f.name === "main.tex" || f.name === "document.tex",
-  );
-  if (fallback) {
-    return { rootId: fallback.id, targetPath: fallback.relativePath };
-  }
-  // Final fallback: use the first available .tex file in the project
+  // No .tex file exists — cannot compile
   const anyTex = files.find((f) => f.type === "tex");
   if (anyTex) {
     return { rootId: anyTex.id, targetPath: anyTex.relativePath };
   }
-  // No .tex file exists — cannot compile
   return null;
 }
 

apps/desktop/src/stores/document-store.ts

@@ -148,25 +148,57 @@ function getActiveFile(state: { files: ProjectFile[]; activeFileId: string }) {
 
 /**
  * Resolve the root .tex file for compilation.
- * Parses `% !TEX root = <file>` magic comment from the first 20 lines.
- * Returns the root file's ID (relativePath), or the input fileId if no root is specified.
+ *
+ * Priority order:
+ * 1. `% !TEX root = <file>` magic comment in the first 20 lines of the active file
+ * 2. The file itself, if it contains `\documentclass`
+ * 3. `main.tex` or `document.tex` that contains `\documentclass`
+ * 4. Any other .tex file in the project that contains `\documentclass`
+ * 5. Fallback: the active file itself
  */
 export function resolveTexRoot(fileId: string, files: ProjectFile[]): string {
   const file = files.find((f) => f.id === fileId);
   if (!file || file.type !== "tex" || !file.content) return fileId;
 
+  // 1. Check for % !TEX root magic comment
   const lines = file.content.split("\n").slice(0, 20);
   for (const line of lines) {
     const match = line.match(/^%\s*!TEX\s+root\s*=\s*(.+)/i);
     if (match) {
       const rootPath = match[1].trim();
-      // Try matching by relative path first, then by filename
       const target =
         files.find((f) => f.relativePath === rootPath) ??
         files.find((f) => f.name === rootPath);
       if (target) return target.id;
     }
   }
+
+  // 2. If the current file contains \documentclass, it is a root file
+  if (/\\documentclass[\s{[]/.test(file.content)) {
+    return fileId;
+  }
+
+  // 3. Look for main.tex or document.tex with \documentclass
+  const wellKnown = files.find(
+    (f) =>
+      (f.name === "main.tex" || f.name === "document.tex") &&
+      f.type === "tex" &&
+      f.content &&
+      /\\documentclass[\s{[]/.test(f.content),
+  );
+  if (wellKnown) return wellKnown.id;
+
+  // 4. Any .tex file with \documentclass
+  const anyRoot = files.find(
+    (f) =>
+      f.type === "tex" &&
+      f.id !== fileId &&
+      f.content &&
+      /\\documentclass[\s{[]/.test(f.content),
+  );
+  if (anyRoot) return anyRoot.id;
+
+  // 5. Fallback: the active file itself
   return fileId;
 }