# Minecraft Mod Updater — Comprehensive LLM Reference Manual
URL: https://mcmods.sednium.com/
Repository: https://github.com/CoderBhoid/Minecraft-Mods-Updater
Publisher: Sednium

## 1. Executive Summary
MC Mod Updater (Minecraft Mods Updater) is an open-source browser application that simplifies the process of managing, checking, updating, and dependency-resolving Minecraft modifications. It bridges the gap between manual `.jar` downloading and full third-party launcher lock-in by operating directly in any modern web browser without requiring executable installations.

## 2. Core Capabilities

### Client-Side Cryptographic Hashing
- When a user uploads `.jar` files, the browser calculates the SHA-1 checksum using the standard Web Cryptography API (`crypto.subtle.digest('SHA-1', arrayBuffer)`).
- The hash is sent to the Modrinth API v2 (`/version_file/{sha1}`) to look up the exact project, current version, author, and loader compatibility without sending the file contents.

### Mod Version Matching & Search Fallback
- If a direct hash match is found, the application fetches all published versions matching the user's selected Game Version and Mod Loader.
- If a hash is unrecognized (e.g., custom compiled build or renamed JAR), the app parses clean semantic tokens from the filename and performs a fuzzy search against the Modrinth project catalog, allowing the user to confirm or override the matched project.

### Dependency Graph & Two-Phase Loading
1. **Phase 1 (Mod Registry Scan)**: All user mods are hashed, identified, and aggregated into memory.
2. **Phase 2 (Dependency Resolution)**: The app inspects all project dependencies (`modrinth_version.dependencies`) and categorizes each as:
   - `required`: Required for the mod to run.
   - `optional`: Enhances the mod.
   - `incompatible`: Conflicts with the mod.
   - The graph cross-references required dependencies against all loaded mods. If missing, a 1-click "Add to Modpack" action is provided to fetch the appropriate library file.

### Modpack Profile System & Sharing Specification
- Profiles store:
  - `name`: String
  - `mcVersion`: Target Minecraft version (e.g. `26.2`, `1.21.4`, `1.20.1`)
  - `loader`: `fabric` | `neoforge` | `forge` | `quilt`
  - `versionType`: `release` | `snapshot`
  - `mods`: Array of mod entries with name, projectId, fileName, isPinned, customLoader, and customVersion.
- Sharing URLs encode the profile state into a base64 JSON payload (`https://mcmods.sednium.com/?profile=<encoded>`).
- Export manifests follow a standard JSON schema importable across sessions.

### File System Access API Integration
- For supported browsers (Chrome, Edge, Opera, Brave), the app provides live directory synchronization with `showDirectoryPicker()`.
- Users can grant write permission to their `.minecraft/mods` directory to write updated JARs and clean up replaced JARs in a single step.

## 3. Frequently Asked Questions (FAQ)

### Q: Does MC Mod Updater upload my mod files?
A: No. All file scanning, checksum hashing, and ZIP extraction happen entirely client-side inside the user's web browser. Only SHA-1 hashes and search queries are sent to public mod repository APIs.

### Q: Which mod loaders are supported?
A: Fabric, NeoForge, Forge, and Quilt.

### Q: Can I use MC Mod Updater on mobile or tablets?
A: Yes. The UI is fully responsive. On mobile devices, users can inspect mod versions, save profiles, and download individual files or export JSON manifests.

### Q: How do I share my modpack with friends?
A: In the Modpack Profile Manager, click the Share icon next to your profile to copy a direct import link (`?profile=...`). When your friends open the link, the app will offer to import and load your exact modpack.

## 4. API Endpoints Used
- Modrinth API v2: `https://api.modrinth.com/v2/`
- Modrinth CDN: `https://cdn.modrinth.com/`
- CurseForge Core API