Add custom output filename template (ENG-649)

main.ts

@@ -13,6 +13,7 @@ import { checkDependencies, installPackage } from './src/utils/python';
 import {
 	getVaultBasePath,
 	resolveOutputFolder,
+	resolveFilenameTemplate,
 	resolveImageDir,
 	toVaultRelative,
 } from './src/utils/paths';
@@ -123,8 +124,11 @@ export default class MarkitdownPlugin extends Plugin {
 
 		const inputPath = path.join(vaultPath, file.path);
 		const outputFolder = resolveOutputFolder(vaultPath, this.settings.outputPath);
-		const baseName = file.basename;
-		const outputPath = path.join(outputFolder, `${baseName}.md`);
+		const resolvedName = resolveFilenameTemplate(
+			this.settings.outputFilenameTemplate || '{filename}',
+			inputPath
+		);
+		const outputPath = path.join(outputFolder, `${resolvedName}.md`);
 		const options = this.buildConversionOptions(outputPath);
 
 		new Notice('Converting file...');

src/modals/FileConvertModal.ts

@@ -3,7 +3,7 @@ import * as path from 'path';
 import * as fs from 'fs';
 import type MarkitdownPlugin from '../../main';
 import { FILE_INPUT_ACCEPT } from '../utils/fileTypes';
-import { getVaultBasePath, resolveOutputFolder, toVaultRelative } from '../utils/paths';
+import { getVaultBasePath, resolveOutputFolder, resolveFilenameTemplate, toVaultRelative } from '../utils/paths';
 
 export class FileConvertModal extends Modal {
 	private plugin: MarkitdownPlugin;
@@ -51,8 +51,11 @@ export class FileConvertModal extends Modal {
 				}
 
 				const outputFolder = resolveOutputFolder(vaultPath, this.plugin.settings.outputPath);
-				const baseName = path.basename(file.name, path.extname(file.name));
-				const outputPath = path.join(outputFolder, `${baseName}.md`);
+				const resolvedName = resolveFilenameTemplate(
+					this.plugin.settings.outputFilenameTemplate || '{filename}',
+					file.name
+				);
+				const outputPath = path.join(outputFolder, `${resolvedName}.md`);
 
 				// Write the DOM File to a temp file on disk
 				const safeName = file.name.replace(/[^a-zA-Z0-9._-]/g, '_');

src/modals/FolderConvertModal.ts

@@ -3,7 +3,7 @@ import * as path from 'path';
 import * as fs from 'fs';
 import type MarkitdownPlugin from '../../main';
 import { EXTENSION_GROUPS } from '../utils/fileTypes';
-import { getVaultBasePath, resolveOutputFolder } from '../utils/paths';
+import { getVaultBasePath, resolveOutputFolder, resolveFilenameTemplate } from '../utils/paths';
 import { BatchProgressModal } from './BatchProgressModal';
 
 export class FolderConvertModal extends Modal {
@@ -119,8 +119,11 @@ export class FolderConvertModal extends Modal {
 			const file = files[i];
 			progressModal?.updateProgress(i, file.name, success, failed);
 
-			const baseName = path.basename(file.name, path.extname(file.name));
-			const outputPath = path.join(outputFolder, `${baseName}.md`);
+			const resolvedName = resolveFilenameTemplate(
+				this.plugin.settings.outputFilenameTemplate || '{filename}',
+				file.name
+			);
+			const outputPath = path.join(outputFolder, `${resolvedName}.md`);
 			const safeName = file.name.replace(/[^a-zA-Z0-9._-]/g, '_');
 			const tempFilePath = path.join(outputFolder, `tmp_${Date.now()}_${i}_${safeName}`);
 

src/settings/SettingsTab.ts

@@ -76,6 +76,21 @@ export class SettingsTab extends PluginSettingTab {
 					await this.plugin.saveSettings();
 				}));
 
+		new Setting(containerEl)
+			.setName('Output filename template')
+			.setDesc(
+				'Template for converted filenames. Variables: {filename} (original name), ' +
+				'{ext} (original extension), {date} (YYYY-MM-DD), {datetime} (YYYY-MM-DD_HHmmss). ' +
+				'The .md extension is always appended automatically.'
+			)
+			.addText(text => text
+				.setPlaceholder('{filename}')
+				.setValue(this.plugin.settings.outputFilenameTemplate)
+				.onChange(async (value) => {
+					this.plugin.settings.outputFilenameTemplate = value || '{filename}';
+					await this.plugin.saveSettings();
+				}));
+
 		new Setting(containerEl)
 			.setName('Extract images')
 			.setDesc('Extract embedded images from PDFs and save as separate files')

src/types/settings.ts

@@ -13,6 +13,7 @@ export interface MarkitdownSettings {
 	imageSubfolderTemplate: string;
 	enableBatchProgress: boolean;
 	enableContextMenu: boolean;
+	outputFilenameTemplate: string;
 }
 
 export const DEFAULT_SETTINGS: MarkitdownSettings = {
@@ -25,6 +26,7 @@ export const DEFAULT_SETTINGS: MarkitdownSettings = {
 	imageSubfolderTemplate: '{filename}-images',
 	enableBatchProgress: true,
 	enableContextMenu: true,
+	outputFilenameTemplate: '{filename}',
 };
 
 export interface ConversionOptions {

src/utils/paths.ts

@@ -37,6 +37,43 @@ export function resolveOutputFolder(vaultPath: string, outputSetting: string): s
 	return outputFolder;
 }
 
+/**
+ * Resolve an output filename template using variables from the input path.
+ * Supported variables:
+ *   {filename} — original file name without extension
+ *   {ext}      — original file extension (without dot)
+ *   {date}     — conversion date as YYYY-MM-DD
+ *   {datetime} — conversion datetime as YYYY-MM-DD_HHmmss
+ *
+ * Returns the resolved name without .md extension (caller appends it).
+ * Characters invalid in filenames are stripped from the result.
+ */
+export function resolveFilenameTemplate(template: string, inputPath: string): string {
+	const baseName = path.basename(inputPath, path.extname(inputPath));
+	const ext = path.extname(inputPath).replace(/^\./, '');
+
+	const now = new Date();
+	const pad = (n: number) => String(n).padStart(2, '0');
+	const date = `${now.getFullYear()}-${pad(now.getMonth() + 1)}-${pad(now.getDate())}`;
+	const datetime = `${date}_${pad(now.getHours())}${pad(now.getMinutes())}${pad(now.getSeconds())}`;
+
+	let resolved = template
+		.replace(/\{filename\}/g, baseName)
+		.replace(/\{ext\}/g, ext)
+		.replace(/\{date\}/g, date)
+		.replace(/\{datetime\}/g, datetime);
+
+	// Remove characters invalid in filenames
+	resolved = resolved.replace(/[/\\:*?"<>|]/g, '');
+
+	// Fall back to the original filename if the result is empty after sanitisation
+	if (!resolved.trim()) {
+		resolved = baseName;
+	}
+
+	return resolved;
+}
+
 /**
  * Compute the image extraction directory for a given output markdown file.
  * Applies the template (e.g., "{filename}-images") to generate the folder name.