feat: add Git staging event listeners and diff pre-warming

Author: Hi7cl4w

package.json

@@ -154,7 +154,7 @@
         "diffy-explain-ai.customCommitPrompt": {
           "type": "string",
           "order": 5,
-          "default": "Generate a commit message for the following git diff.\n\nRequirements:\n- Maximum subject length: {maxLength} characters\n- Use imperative mood\n- Be concise and clear{bodyInstructions}\n\nReturn ONLY the commit message, no explanations.",
+          "default": "Generate a commit message for the following git diff.\n\nRequirements:\n- Maximum subject length: {maxLength} characters\n- Use imperative mood\n- Be concise and clear{bodyInstructions}\n\nReturn ONLY the commit message, no explanations.\nDo not wrap the response in code blocks, backticks, or any markdown formatting.",
           "editPresentation": "multilineText",
           "markdownDescription": "Custom prompt template for commit message generation.\n\nAvailable placeholders: `{maxLength}`, `{bodyInstructions}`, `{locale}`, `{diff}`.\n\nUsed when Commit Message Type is set to `custom`."
         },
@@ -236,10 +236,10 @@
         "diffy-explain-ai.maxIndexedFileSize": {
           "type": "number",
           "order": 10,
-          "default": 100,
+          "default": 50,
           "minimum": 10,
           "maximum": 500,
-          "markdownDescription": "**Maximum File Size for Analysis**\n\nFiles larger than this are skipped during codebase indexing.\n\n**Default:** 100 KB (sufficient for most config files)\n\n**Guidelines:**\n- `50 KB` - Conservative (skips larger READMEs)\n- `100 KB` - Balanced *(recommended)*\n- `200+ KB` - Permissive (may include large docs)\n\n> Larger limits increase token usage and API costs."
+          "markdownDescription": "**Maximum File Size for Analysis**\n\nFiles larger than this are skipped during codebase indexing.\n\n**Default:** 50 KB (conservative, skips larger READMEs)\n\n**Guidelines:**\n- `50 KB` - Conservative *(recommended)*\n- `100 KB` - Balanced (sufficient for most config files)\n- `200+ KB` - Permissive (may include large docs)\n\n> Larger limits increase token usage and API costs."
         },
         "diffy-explain-ai.codebaseContextTokenBudget": {
           "type": "number",

src/Diffy.ts

@@ -605,6 +605,42 @@ class Diffy extends BaseDiffy {
     }
   }
 
+  /**
+   * Update staged changes when Git staging area changes
+   * Pre-warms diff context preparation in background for faster commit generation
+   */
+  async updateStagedChanges() {
+    try {
+      // Check if we have a valid workspace and repo
+      if (!this.workspaceService?.checkAndWarnWorkSpaceExist()) {
+        return;
+      }
+      if (!this.gitService?.checkAndWarnRepoExist()) {
+        return;
+      }
+
+      const repo = this.gitService?.getCurrentRepo();
+      if (!repo) {
+        return;
+      }
+
+      // Get current staged diff in background
+      const diff = await this.gitService?.getDiffAndWarnUser(repo, false);
+      if (!diff) {
+        return;
+      }
+
+      // Pre-warm the diff context preparation in background
+      this.prepareDiffWithContext(diff).catch((error) => {
+        logger.error("Error pre-warming diff context", error);
+      });
+
+      logger.info("Staged changes updated - pre-warming diff context");
+    } catch (error) {
+      logger.error("Error in updateStagedChanges", error);
+    }
+  }
+
   /**
    * Dispose all objects
    */

src/extension.ts

@@ -1,14 +1,60 @@
 // The module 'vscode' contains the VS Code extensibility API
 // Import the module and reference it with the alias vscode in your code below
 import * as vscode from "vscode";
+import type { API as GitApi, GitExtension, Repository } from "./@types/git";
 import Diffy from "./Diffy";
 
 let app: Diffy | null = null;
 
+function setupGitStagingEventListeners(context: vscode.ExtensionContext) {
+  const gitExtension = vscode.extensions.getExtension<GitExtension>("vscode.git");
+  if (!gitExtension) {
+    return;
+  }
+
+  const gitApi = gitExtension.exports.getAPI(1);
+  if (!gitApi) {
+    return;
+  }
+
+  // Listen for changes in the Git staging area
+  gitApi.repositories.forEach((repo: Repository) => {
+    const onDidChangeRepository = repo.state.onDidChange;
+    if (onDidChangeRepository) {
+      context.subscriptions.push(
+        onDidChangeRepository(() => {
+          // Update the Diffy app when the repository state changes
+          app?.updateStagedChanges().catch((error) => {
+            console.error("Error updating staged changes:", error);
+          });
+        }),
+      );
+    }
+  });
+
+  // Also listen for new repositories being added
+  context.subscriptions.push(
+    gitApi.onDidOpenRepository((repo: Repository) => {
+      const onDidChangeRepository = repo.state.onDidChange;
+      if (onDidChangeRepository) {
+        context.subscriptions.push(
+          onDidChangeRepository(() => {
+            app?.updateStagedChanges().catch((error) => {
+              console.error("Error updating staged changes:", error);
+            });
+          }),
+        );
+      }
+    }),
+  );
+}
+
 export function activate(context: vscode.ExtensionContext) {
   app = new Diffy(context);
   app.init();
 
+  setupGitStagingEventListeners(context);
+
   context.subscriptions.push(
     vscode.commands.registerCommand("diffy-explain-ai.explainDiffClipboard", () => {
       return app?.explainDiffToClipboard();

src/service/WorkspaceService.ts

@@ -167,7 +167,8 @@ Requirements:
 - Use imperative mood
 - Be concise and clear{bodyInstructions}
 
-Return ONLY the commit message, no explanations.`;
+Return ONLY the commit message, no explanations.
+Do not wrap the response in code blocks, backticks, or any markdown formatting.`;
   }
 
   getIncludeCommitBody() {