Suggestion to Improve Nexus Download Collection

This document proposes adopting the enhanced implementation for Nexus Download Collection, highlighting why the changes are technically beneficial, safer, and more user-friendly compared to the current behavior.

Overview

The current Nexus Download Collection workflow relies on indirect signals (timeouts, redirects, or assumed completion) to manage downloads. The proposed improvements replace this approach with real download lifecycle control, leveraging GM_download to gain full visibility into progress, success, failure, and cancellation states.

These changes significantly improve reliability, user experience, and long-term maintainability.

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Key Improvement Suggestions

1. Replace Time-Based Assumptions with Real Download Control

Problem in the current implementation:
Downloads are triggered via redirects or simulated clicks, without knowing whether a download actually started, completed, or failed.

Suggested improvement:
Adopt an async/await-based flow using GM_download, allowing Nexus Download Collection to explicitly wait for:

• Successful completion
  
• User cancellation (pause/stop)
  
• Errors (including Tampermonkey restrictions)

Benefit:
Eliminates race conditions, incorrect timing estimates, and false positives where a download is assumed complete but isn’t.

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2. Introduce a Dedicated Download Abstraction

Suggestion:
Encapsulate all download logic inside a single Promise-based helper (e.g. downloadWithGM).

This abstraction should:

• Track progress in real time
  
• Calculate actual download speed and ETA
  
• Resolve cleanly on success, abort, or error
  

Benefit:

• Cleaner control flow
  
• Easier debugging
  
• Centralized error handling
  
• Future extensibility (retry logic, per-host rules, etc.)

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3. Fix Pause and Stop Semantics

Problem:
Pause/Stop currently prevents only the next download from starting, while the active transfer continues.

Suggested improvement:
Store the active GM_download control object and explicitly call .abort() when the user pauses or stops.

Benefit:

• Immediate response to user actions
  
• No wasted bandwidth
  
• Behavior matches user expectations
  

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4. Preserve Correct File Names and Extensions

Problem:
Using display names instead of real filenames can cause:

• Incorrect file extensions
  
• Tampermonkey blocking downloads (.7z, .rar, etc.)

Suggested improvement:
Always use the real file identifier (e.g. file URI) when passing the name parameter to GM_download.

Benefit:

• Prevents extension mismatch
  
• Improves compatibility with Tampermonkey security rules
  

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5. Detect and Handle Tampermonkey Whitelist Errors Explicitly

Suggestion:
Add explicit detection for the not_whitelisted error reason and notify the user when Tampermonkey blocks a file type.

Benefit:

• Prevents silent failures
  
• Reduces user confusion
  
• Provides a clear path to resolution (extension whitelisting)

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6. Upgrade the UI to Reflect Real-Time Download State

Suggested UI changes:

• Remove manual speed input fields
  
• Display:
  • Per-file progress bar
    
  • Real download speed
    
  • Estimated time remaining (ETA)

Benefit:

• UI reflects real data instead of assumptions
  
• Cleaner interface
  
• Improved user trust and transparency
  

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7. Update Script Metadata

Suggestion:
Ensure Nexus Download Collection metadata includes:

• @grant GM_download
  
• @updateURL
  
• @downloadURL
  

Benefit:

• Enables full functionality
  
• Supports automatic updates
  
• Improves long-term maintainability
  

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Final Recommendation

These improvements elevate Nexus Download Collection from a best-effort trigger-based downloader to a fully managed download system with:

• Deterministic behavior
  
• Accurate progress tracking
  
• Proper cancellation
  
• Robust error handling
  

From both a technical and UX standpoint, this aligns Nexus Download Collection with modern download manager expectations and significantly improves reliability for end users.