# JWT 401 Error - Root Cause and Resolution

## Problem
Getting "HTTP 401: Invalid JWT" errors throughout the app.

## Root Cause Identified ✓

The JWT being sent has algorithm **ES256** (Elliptic Curve), but your Supabase project expects **HS256** (HMAC).

**Evidence:**
```
DEBUG: Sending JWT (first 50 chars): eyJhbGciOiJFUzI1NiIsImtpZCI6ImI2NmJjNThkLTM0YjgtND...
                                              ^^^^^^^^
                                              ES256 algorithm
```

Your project's anon key:
```
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
          ^^^^^^^^
          HS256 algorithm
```

## What This Means

You were previously signed into a **different Supabase project** that uses ES256 JWTs. The app cached that session, and even though you're now passing the correct credentials via environment variables, the **old cached session** is being used for all API calls.

## Solution Applied ✓

1. **Uninstalled the app** completely from your Pixel 9
2. **Reinstalling with fresh credentials** (no cached session)

## What Will Happen Next

After reinstall:
1. App will have NO cached session
2. You'll see the sign-in screen
3. When you sign in, Supabase will create a session with **HS256 JWT** (matching your project)
4. All API calls will succeed
5. JWT errors will be gone

## Verification

After the app reinstalls and you sign in, check the console for:

**BEFORE (Wrong):**
```
DEBUG: Sending JWT (first 50 chars): eyJhbGciOiJFUzI1NiIsImtpZCI6...
```

**AFTER (Correct):**
```
DEBUG: Sending JWT (first 50 chars): eyJhbGciOiJIUzI1NiIsInR5cCI6...
```

The algorithm should be **HS256**, not ES256.

## Other Fixes Applied

While troubleshooting, we also:

1. ✅ **Verified database functions exist**
   - `has_block_between()` - EXISTS
   - `is_mutual_follow()` - EXISTS

2. ✅ **Verified Edge Functions are deployed**
   - `signup` - Deployed
   - `profile` - Deployed
   - `feed-sojorn` - Deployed
   - `feed-personal` - Deployed

3. ✅ **Added error handling** to [api_service.dart](c:\Webs\Sojorn\sojorn_app\lib\services\api_service.dart)
   - `hasProfile()` - Now gracefully handles errors
   - `hasCategorySelection()` - Now gracefully handles errors
   - Added debug logging to see JWT details

4. ✅ **Created deployment and diagnostic tools**
   - [DEPLOY_EDGE_FUNCTIONS.md](c:\Webs\Sojorn\DEPLOY_EDGE_FUNCTIONS.md)
   - [TROUBLESHOOTING_JWT.md](c:\Webs\Sojorn\TROUBLESHOOTING_JWT.md)
   - [test_edge_functions.ps1](c:\Webs\Sojorn\test_edge_functions.ps1)
   - [check_rls_setup.sql](c:\Webs\Sojorn\supabase\diagnostics\check_rls_setup.sql)

## If Issue Persists

If you still see ES256 after reinstall, it means:

1. The app is reading credentials from somewhere else (check for hardcoded values)
2. You're signing in with an account from a different Supabase project
3. There's a Supabase session restore happening from cloud backup

**Next debug step:**
Check the actual Supabase URL being used:
```dart
print('Supabase URL: ${Supabase.instance.client.supabaseUrl}');
print('Expected: https://zwkihedetedlatyvplyz.supabase.co');
```

## Summary

**Issue:** Cached session from wrong Supabase project (ES256 vs HS256)
**Fix:** Complete app uninstall/reinstall
**Status:** Reinstalling now...
**Next:** Sign in and verify JWT shows HS256