# Obsidian LeetTrack

> [!NOTE]
> **Disclaimer:** This plugin is **vibe coded** — built rapidly with AI assistance and creative energy rather than traditional software engineering rigor. It works well for my personal workflow, but expect rough edges. Use at your own risk, and feel free to open issues or contribute fixes!

Create organized LeetCode problem notes with auto-fetched metadata, smart topic categorization, and spaced repetition review tracking — all inside your Obsidian vault.

![Obsidian](https://img.shields.io/badge/Obsidian-%23483699.svg?logo=obsidian&logoColor=white)
![License](https://img.shields.io/github/license/Chillaxhson/obsidian-leet-track)
![GitHub release](https://img.shields.io/github/v/release/Chillaxhson/obsidian-leet-track)

---

## Features

### One-Click Problem Note Creation

Enter a LeetCode URL, Problem ID, or title slug — the plugin fetches all metadata (title, difficulty, topic tags) from the LeetCode GraphQL API and creates a fully structured note.

**Accepts any input format:**
- Full URL: `https://leetcode.com/problems/trapping-rain-water/`
- Problem ID: `42`
- Title slug: `two-sum`, `3Sum`

### Smart Topic Categorization

Notes are automatically filed into topic folders matching the **LeetCode Top Interview 150** roadmap:

| Folder | Topics |
|---|---|
| `01 - Array & String` | Arrays, strings, in-place operations |
| `02 - Two Pointers` | Two-pointer techniques |
| `03 - Sliding Window` | Window-based problems |
| `04 - Matrix` | 2D grid problems |
| `05 - Hashmap` | Hash table lookups |
| `06 - Linked List` | Singly/doubly linked lists |
| `07 - Stack` | Stack, monotonic stack |
| `08 - Intervals` | Interval merging/insertion |
| `09 - Binary Tree` | Tree traversal, BST |
| `10 - Graph` | BFS, DFS, graph theory |
| `11 - Trie & Search` | Trie data structure |
| `12 - Backtracking` | Combinatorial search |
| `13 - Binary Search` | Search algorithms |
| `14 - Heap` | Priority queue problems |
| `15 - Dynamic Programming` | DP, memoization |
| `16 - Math & Bit` | Math tricks, bit manipulation |

Problems not in the Top 150 are categorized by their LeetCode tags. You can also define **custom topic mappings** in settings.

### Mastery & Spaced Repetition System

Track your learning progress with a three-level mastery system:

| Mastery | Meaning | Default Review Interval |
|---|---|---|
| 🔴 **Red** | Missed pattern or forgot logic | 1 day |
| 🟡 **Yellow** | Understood pattern but stumbled on code | 3 days |
| 🟢 **Green** | Solved quickly with clear understanding | 7 days |

The plugin manages the full learning lifecycle:

```
Import Problem → Study / Solve → Set Mastery
       ↑                              ↓
  Reschedule  ←  Update Mastery  ←  Review
```

**Review scheduling** is automatic — when you update mastery, the next review date is calculated and stored in the note's frontmatter. The **"Show Problems Due for Review"** command lists all overdue problems.

You can also **mark a problem as reviewed** without changing its mastery level — this bumps the review date forward based on the current mastery and increments the review count. Available as a command or via the ✅ button in the Due Reviews modal.

### Batch Import

Import multiple problems at once. Paste a list of IDs, URLs, or slugs — one per line — and the plugin creates all notes with progress tracking and a summary showing imported/skipped/failed counts.

### Auto-Updating Hub Dashboard

A living `00 - LeetCode Hub.md` dashboard with:
- **Due for Review** — problems requiring immediate attention
- **Progress Overview** — mastery distribution (Red/Yellow/Green)
- **Statistics** — study streak, solve counts, difficulty distribution
- **Review Queue** — all Red and Yellow problems
- **Mastered Problems** — your Green list
- **Topic Breakdown** — categorized problem lists

### LeetCode CN Support

Toggle between `leetcode.com` and `leetcode.cn` in settings for users in China.

---

## Installation

### Community Plugins (Recommended)

1. Open **Settings** → **Community plugins** → **Browse**
2. Search for **"LeetTrack"**
3. Click **Install**, then **Enable**

### Manual Installation

1. Download `main.js`, `manifest.json`, and `styles.css` from the [latest release](https://github.com/Chillaxhson/obsidian-leet-track/releases)
2. Create a folder `<your-vault>/.obsidian/plugins/obsidian-leet-track/`
3. Copy the three files into that folder
4. Restart Obsidian and enable the plugin in **Settings** → **Community plugins**

### BRAT (Beta Testing)

1. Install the [BRAT plugin](https://github.com/TfTHacker/obsidian42-brat)
2. Add beta plugin: `Chillaxhson/obsidian-leet-track`

---

## Usage

### Commands

All commands are accessible via the Command Palette (`Cmd/Ctrl + P`):

| Command | Description |
|---|---|
| **Create new problem note** | Open the input modal to create a single problem note |
| **Batch import problem notes** | Import multiple problems at once |
| **Refresh hub dashboard** | Regenerate the dashboard from current vault state |
| **Update problem mastery** | Set mastery level (Red/Yellow/Green) for the active note |
| **Show problems due for review** | List all problems past their review date |
| **Mark current problem as reviewed** | Bump the review date without changing mastery |

The ribbon icon (code icon in the left sidebar) opens the **Create new problem note** modal.

### Frontmatter

Each problem note includes structured YAML frontmatter:

```yaml
---
difficulty: Medium
mastery: red
tags:
  - leetcode-interview-150
  - array
  - two-pointers
created-date: 2026-08-28
review-date: 2026-08-29
review-count: 0
---
```

| Field | Description |
|---|---|
| `difficulty` | Easy, Medium, or Hard |
| `mastery` | `red`, `yellow`, or `green` |
| `tags` | LeetCode topic tags + `leetcode-interview-150` if applicable |
| `created-date` | When the note was generated |
| `solved-date` | When you first marked mastery (set automatically) |
| `review-date` | Next scheduled review date |
| `review-count` | Number of times you've reviewed this problem |

---

## Settings

| Setting | Default | Description |
|---|---|---|
| **LeetCode root folder** | `LeetCode` | Relative path to your LeetCode notes directory |
| **Dashboard filename** | `00 - LeetCode Hub.md` | Name of the hub dashboard file |
| **Auto-update hub dashboard** | `true` | Refresh dashboard when notes are created/updated |
| **Include problem description** | `false` | Fetch and embed the problem description (HTML → Markdown) |
| **Use LeetCode CN** | `false` | Switch to `leetcode.cn` API and URLs |
| **Default mastery (Easy)** | `green` | Initial mastery for Easy problems |
| **Default mastery (Med/Hard)** | `red` | Initial mastery for Medium and Hard problems |
| **Red interval** | `1 day` | Days until next review when mastery is Red |
| **Yellow interval** | `3 days` | Days until next review when mastery is Yellow |
| **Green interval** | `7 days` | Days until next review when mastery is Green |
| **Custom topic mappings** | `{}` | Override tag → topic folder mappings |

---

## FAQ

### The LeetCode API request failed

The plugin uses the public LeetCode GraphQL API. If you get rate-limited (HTTP 429), the plugin will automatically retry with exponential backoff (up to 3 retries). If it still fails, wait a few minutes and try again.

### Can I customize the note template?

Yes — the template is stored in the plugin settings (accessible via `data.json` in your vault's plugin folder). Available template variables:

```
{{id}}, {{title}}, {{difficulty}}, {{mastery}}, {{tags}},
{{url}}, {{topicFolder}}, {{created-date}}, {{review-date}},
{{description}}, {{#description}}...{{/description}}
```

### Does it work on mobile?

Yes. The plugin uses only Obsidian's built-in `requestUrl` API (no Node.js/Electron dependencies) and is marked `isDesktopOnly: false`.

### I already have notes from the old LeetCode Helper plugin

The plugin automatically migrates legacy settings and reads both the old `status` field and the new `mastery` field from frontmatter.

---

## Contributing

### Development Setup

```bash
git clone https://github.com/Chillaxhson/obsidian-leet-track.git
cd obsidian-leet-track
npm install
npm run dev    # Watch mode — rebuilds on every save
```

### Building for Production

```bash
npm run build  # Type-check + minified production build
```

### Project Structure

```
src/
├── main.ts              # Plugin entry point
├── types.ts             # All TypeScript interfaces
├── constants.ts         # Top 150 map, topic logic
├── api/
│   └── leetcode.ts      # GraphQL client with retry
├── services/
│   ├── problem-service.ts    # Note creation
│   ├── review-service.ts     # Mastery lifecycle
│   └── dashboard-service.ts  # Hub dashboard
├── modals/
│   ├── input-modal.ts        # Single problem input
│   ├── batch-import-modal.ts # Batch import
│   └── review-modal.ts       # Mastery update
├── settings.ts          # Settings tab + migration
└── utils/
    ├── parser.ts        # HTML → Markdown
    └── date.ts          # Review date calculations
```

---

## License

[MIT](LICENSE) © Chillaxhson