fix: resolve debugger issues with simulator endianness, FBD visualization, and forced variable polling

[thiagoralves]

Summary

• Simulator endianness detection: The simulator debug flow skipped the getMd5Hash() call that triggers set_endianness() on the emulated AVR runtime. This caused multi-byte forced values to be byte-swapped on the little-endian AVR emulator (e.g., forcing INT to 1 displayed as 256). Now getMd5Hash() is called after connecting in the simulator path of handleDebuggerConnect.

• FBD BOOL edge coloring: Compiler-generated _TMP_ function output variables (e.g., _TMP_GT3058168_OUT) were only registered in the debug variable info map for Ladder flows, not FBD. This meant function BOOL outputs were never polled and FBD edges were never painted green. Extracted a shared registerFunctionTempOutputs helper used by both LD and FBD. Also added the missing getCompositeKey dependency to the FBD styledEdges useMemo (Ladder already had it).

• Forced variable polling: Variables forced from the diagram (FBD or Ladder) were added to debugForcedVariables but never included in the debugVariableKeys polling set. Their values never appeared in the debugger panel (showed "-" or stale data). Now all forced variable composite keys are added to debugVariableKeys before building the poll list.

Test plan

• Open a program with an FBD GT block connected to BOOL variables, run the simulator debugger, force IN1 > IN2, and verify the OUT edge turns green
• Force an INT variable to value 1 in the simulator and verify it displays as 1 (not 256)
• Force a variable from the FBD/LD diagram without first adding it to the debugger panel via the debug icon, and verify its value appears in the panel
• Verify Ladder debug visualization still works correctly (no regressions)
• Test on real hardware to confirm no regressions in the non-simulator debug flow

🤖 Generated with Claude Code

Summary by CodeRabbit

Release Notes

• New Features

  • Expanded debugging workspace to support Function Block Diagram (FBD) flows alongside Ladder Logic.
  • Enhanced automatic polling and monitoring of function block outputs and temporary variables for improved debugging visibility.

• Bug Fixes

  • Improved endianness detection when connecting to emulated environments for accurate multi-byte value handling.

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📥 Commits

Reviewing files that changed from the base of the PR and between 26b402d and 11d5fe9.

📒 Files selected for processing (3)

• src/main/modules/ipc/main.ts
• src/renderer/components/_molecules/graphical-editor/fbd/index.tsx
• src/renderer/screens/workspace-screen.tsx

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Walkthrough

This PR adds endianness detection for simulator connections via Modbus, fixes FBD editor memoization by including getCompositeKey in dependency array, and extends debugger variable polling to support FBD POUs alongside LD with forced variable integration.

Changes

Cohort / File(s)	Summary
Simulator Endianness Detection src/main/modules/ipc/main.ts	Calls getMd5Hash on Modbus client after establishing simulator connection to trigger runtime endianness detection and byte-order configuration.
FBD Editor Memoization src/renderer/components/_molecules/graphical-editor/fbd/index.tsx	Adds getCompositeKey to the dependency array of FBDBody's styledEdges useMemo to ensure recomputation when the function changes.
Debugger Variable Polling Expansion src/renderer/screens/workspace-screen.tsx	Adds FBD flow retrieval and processing alongside LD flows; introduces registerFunctionTempOutputs helper to centralize function-block output polling; extends polling to include FBD-specific variable nodes, automatic ENO polling for enabled execution control, and forced variable inclusion via composite-key mapping.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• fix: show online debug values for structured data types and FB instances #614: Modifies debug-variable polling in workspace-screen.tsx to expand composite/FB variable collection alongside main PR's forced variable polling.
• fix: resolve serial debugger spurious values from concurrent polling bugs #618: Modifies getMd5Hash and Modbus request/serialization code directly used by the endianness-detection call added in main PR.
• fix: display global variable values consistently across all programs #597: Modifies polling and composite-key handling in workspace-screen.tsx for FB/FBD variable support, aligning with main PR's polling expansion logic.

Suggested labels

bug

Suggested reviewers

• vmleroy
• JoaoGSP
• JulioSergioFS

Poem

🐰 A byte-swapping hop, endianness in sight,
FBD flows now polled with composite might,
Forced variables dance in the debugger's care,
Memoized deps aligned everywhere! ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	❓ Inconclusive	The description provides a comprehensive summary of changes and a test plan, but lacks required sections like issue references, DOD checklist completion, and test coverage metrics.	Add issue/Jira references, fill out the DOD checklist with checkmarks, and specify test coverage percentage to meet template requirements.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the three main fixes: simulator endianness, FBD visualization, and forced variable polling.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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