feat: add template variables support for default task folder (#413)

Enable dynamic folder creation using template variables in the tasksFolder setting.

Features:
- Task variables: {{context}}, {{project}}, {{priority}}, {{status}}, {{title}}
- Date variables: {{year}}, {{month}}, {{day}}, {{date}}
- Works for both regular task creation and inline conversion
- Automatic folder creation and title sanitization
- Comprehensive documentation with examples

Examples:
- Tasks/{{year}}/{{month}} → Tasks/2025/08
- {{project}}/{{priority}} → ProjectName/high
- {{context}}/{{date}} → WorkContext/2025-08-15

Resolves #376

docs/settings/task-defaults.md

@@ -8,6 +8,91 @@ You can specify a **Default Tasks Folder** where new tasks will be created. You
 
 TaskNotes also provides a system for **Filename Generation**. You can choose from a variety of patterns, including title-based, timestamp-based, and Zettelkasten-style, or you can create your own custom filename template.
 
+### Folder Template Variables
+
+The **Default Tasks Folder** setting supports dynamic folder creation using template variables. This allows you to automatically organize tasks into folders based on their properties and the current date.
+
+#### Available Template Variables
+
+**Task Variables:**
+- `{{context}}` - First context from the task's contexts array
+- `{{project}}` - First project from the task's projects array  
+- `{{priority}}` - Task priority (e.g., "high", "medium", "low")
+- `{{status}}` - Task status (e.g., "todo", "in-progress", "done")
+- `{{title}}` - Task title (sanitized for folder names)
+
+**Date Variables:**
+- `{{year}}` - Current year (e.g., "2025")
+- `{{month}}` - Current month with leading zero (e.g., "08")
+- `{{day}}` - Current day with leading zero (e.g., "15")
+- `{{date}}` - Full current date (e.g., "2025-08-15")
+
+#### Template Examples
+
+**Date-based Organization:**
+```
+Tasks/{{year}}/{{month}}
+→ Tasks/2025/08
+
+Tasks/{{year}}/{{date}}
+→ Tasks/2025/2025-08-15
+```
+
+**Project-based Organization:**
+```
+{{project}}/{{year}}
+→ ProjectName/2025
+
+Projects/{{project}}/{{context}}
+→ Projects/ProjectName/ContextName
+```
+
+**Priority and Status Organization:**
+```
+Tasks/{{priority}}/{{status}}
+→ Tasks/high/todo
+
+{{status}}/{{priority}}/{{year}}
+→ todo/high/2025
+```
+
+**Mixed Organization:**
+```
+{{project}}/{{year}}/{{month}}/{{priority}}
+→ ProjectName/2025/08/high
+
+Tasks/{{context}}/{{date}}
+→ Tasks/ContextName/2025-08-15
+```
+
+#### Important Notes
+
+- **Variable Processing**: Variables are processed when the task is created, using the actual task properties
+- **Missing Values**: If a task doesn't have a value for a variable (e.g., no context assigned), the variable is replaced with an empty string
+- **Multiple Values**: For arrays like contexts and projects, only the first value is used
+- **Title Sanitization**: The `{{title}}` variable automatically removes invalid folder characters (`<>:"/\|?*`) and replaces them with underscores
+- **Folder Creation**: Folders are automatically created if they don't exist
+- **Inline Tasks**: Template variables also work for the inline task conversion folder setting
+
+#### Advanced Usage
+
+**Conditional Folder Structures:**
+Since missing variables become empty strings, you can create conditional folder structures:
+```
+Tasks/{{project}}/{{context}}/{{year}}
+```
+- If both project and context exist: `Tasks/ProjectName/ContextName/2025`
+- If only project exists: `Tasks/ProjectName//2025` (note the double slash)
+- If neither exists: `Tasks///2025`
+
+**Combining with Static Paths:**
+```
+Work/{{project}}/{{year}}/{{status}}
+Archive/{{year}}/{{month}}/{{project}}
+```
+
+This feature provides powerful flexibility for automatically organizing your tasks into meaningful folder structures based on their properties and creation date.
+
 ### Store Title Exclusively in Filename
 
 This setting provides an alternative way to manage your task titles. When enabled, the task's title will be used as the filename, and the `title` property will be removed from the frontmatter. This is a significant data storage change that simplifies frontmatter but disables all other filename templating options.

src/services/TaskService.ts

@@ -4,6 +4,7 @@ import { Notice, TFile, normalizePath, stringifyYaml } from 'obsidian';
 import { TemplateData, mergeTemplateFrontmatter, processTemplate } from '../utils/templateProcessor';
 import { addDTSTARTToRecurrenceRule, ensureFolderExists, updateToNextScheduledOccurrence } from '../utils/helpers';
 import { formatDateForStorage, getCurrentDateString, getCurrentTimestamp } from '../utils/dateUtils';
+import { format } from 'date-fns';
 
 import TaskNotesPlugin from '../main';
 
@@ -20,6 +21,81 @@ export class TaskService {
         this.webhookNotifier = notifier;
     }
 
+    /**
+     * Process a folder path template with task and date variables
+     * 
+     * This method enables dynamic folder creation by replacing template variables 
+     * with actual values from the task data and current date.
+     * 
+     * Supported task variables:
+     * - {{context}} - First context from the task's contexts array
+     * - {{project}} - First project from the task's projects array  
+     * - {{priority}} - Task priority (e.g., "high", "medium", "low")
+     * - {{status}} - Task status (e.g., "todo", "in-progress", "done")
+     * - {{title}} - Task title (sanitized for folder names)
+     * 
+     * Supported date variables:
+     * - {{year}} - Current year (e.g., "2025")
+     * - {{month}} - Current month with leading zero (e.g., "08")
+     * - {{day}} - Current day with leading zero (e.g., "15")
+     * - {{date}} - Full current date (e.g., "2025-08-15")
+     * 
+     * @param folderTemplate - The template string with variables to process
+     * @param taskData - Optional task data for variable substitution
+     * @param date - Date to use for date variables (defaults to current date)
+     * @returns Processed folder path with variables replaced
+     * 
+     * @example
+     * processFolderTemplate("Tasks/{{year}}/{{month}}", taskData)
+     * // Returns: "Tasks/2025/08"
+     * 
+     * @example 
+     * processFolderTemplate("{{project}}/{{priority}}", taskData)
+     * // Returns: "ProjectName/high"
+     */
+    private processFolderTemplate(folderTemplate: string, taskData?: TaskCreationData, date: Date = new Date()): string {
+        if (!folderTemplate) {
+            return folderTemplate;
+        }
+
+        let processedPath = folderTemplate;
+        
+        // Replace task variables if taskData is provided
+        if (taskData) {
+            // Handle single context (first one if multiple)
+            const context = Array.isArray(taskData.contexts) && taskData.contexts.length > 0 
+                ? taskData.contexts[0] 
+                : '';
+            processedPath = processedPath.replace(/\{\{context\}\}/g, context);
+            
+            // Handle single project (first one if multiple) 
+            const project = Array.isArray(taskData.projects) && taskData.projects.length > 0
+                ? taskData.projects[0]
+                : '';
+            processedPath = processedPath.replace(/\{\{project\}\}/g, project);
+            
+            // Handle priority
+            const priority = taskData.priority || '';
+            processedPath = processedPath.replace(/\{\{priority\}\}/g, priority);
+            
+            // Handle status
+            const status = taskData.status || '';
+            processedPath = processedPath.replace(/\{\{status\}\}/g, status);
+            
+            // Handle title (sanitized for folder names)
+            const title = taskData.title ? taskData.title.replace(/[<>:"/\\|?*]/g, '_') : '';
+            processedPath = processedPath.replace(/\{\{title\}\}/g, title);
+        }
+        
+        // Replace date variables with current date values
+        processedPath = processedPath.replace(/\{\{year\}\}/g, format(date, 'yyyy'));
+        processedPath = processedPath.replace(/\{\{month\}\}/g, format(date, 'MM'));
+        processedPath = processedPath.replace(/\{\{day\}\}/g, format(date, 'dd'));
+        processedPath = processedPath.replace(/\{\{date\}\}/g, format(date, 'yyyy-MM-dd'));
+        
+        return processedPath;
+    }
+
     /**
      * Create a new task file with all the necessary setup
      * This is the central method for task creation used by all components
@@ -68,6 +144,7 @@ export class TaskService {
             const baseFilename = generateTaskFilename(filenameContext, this.plugin.settings);
             
             // Determine folder based on creation context
+            // Process folder templates with task and date variables for dynamic folder organization
             let folder = '';
             if (taskData.creationContext === 'inline-conversion') {
                 // For inline conversion, use the inline task folder setting with variable support
@@ -82,13 +159,17 @@ export class TaskService {
                     } else {
                         folder = inlineFolder;
                     }
+                    // Process task and date variables in the inline folder path
+                    folder = this.processFolderTemplate(folder, taskData);
                 } else {
                     // Fallback to default tasks folder when inline folder is empty (#128)
-                    folder = this.plugin.settings.tasksFolder || '';
+                    const tasksFolder = this.plugin.settings.tasksFolder || '';
+                    folder = this.processFolderTemplate(tasksFolder, taskData);
                 }
             } else {
                 // For manual creation and other contexts, use the general tasks folder
-                folder = this.plugin.settings.tasksFolder || '';
+                const tasksFolder = this.plugin.settings.tasksFolder || '';
+                folder = this.processFolderTemplate(tasksFolder, taskData);
             }
             
             // Ensure folder exists