fix: resolve CodeQL complex-condition alert and PerformanceView MVVM violation

[laurentiu021]

Summary

Two code quality improvements:

1. CodeQL alert #302 — complex condition (ProcessManagerViewModel)

The MatchesDescription method had 3 chained || with null-conditional operators, triggering CodeQL's cs/complex-condition rule. Replaced with a ReadOnlySpan<string?> loop that checks each field individually — same behavior, lower cyclomatic complexity.

2. PerformanceView MVVM violation

The code-behind had:

• A PropertyChanged subscription to sync radio buttons from ViewModel
• A Checked event handler to push radio button selection back to ViewModel

Both are now replaced by a reusable EqualityConverter with two-way binding. Code-behind reduced from 55 lines to 14 (just InitializeComponent).

Files changed

• ProcessManagerViewModel.cs — simplified MatchesDescription
• PerformanceView.xaml — radio buttons use converter binding
• PerformanceView.xaml.cs — removed all code-behind logic
• Helpers/EqualityConverter.cs — new reusable converter
• App.xaml — registered IsEqual converter
• EqualityConverterTests.cs — 10 unit tests
• CHANGELOG.md — updated

Testing

• Build: 0 errors (main + tests)
• 10 new unit tests for EqualityConverter (Convert, ConvertBack, null, case sensitivity)

Summary by CodeRabbit

Release Notes

• Bug Fixes

  • Improved code quality and fixed performance-related issues.
  • Enhanced radio button behavior in the Performance settings for more reliable selection.

• Tests

  • Added comprehensive unit test coverage for converter functionality.

• Refactor

  • Simplified internal logic to improve maintainability and performance.

[coderabbitai]

📝 Walkthrough

Walkthrough

Introduces a reusable WPF EqualityConverter for two-way binding equality checks, applies it to refactor PerformanceView's radio-button selection from event-driven code-behind to pure XAML binding, refactors ProcessManagerViewModel.MatchesDescription to use ReadOnlySpan for code-quality compliance, and documents all changes in the changelog.

Changes

EqualityConverter & PerformanceView Binding

Layer / File(s)	Summary
EqualityConverter Implementation & Registration SysManager/SysManager/Helpers/EqualityConverter.cs, SysManager/SysManager/App.xaml	EqualityConverter is a sealed WPF IValueConverter implementing two-way equality comparison: Convert returns false when value or parameter is null, otherwise compares via ordinal ToString() equality; ConvertBack returns parameter on true, Binding.DoNothing otherwise. Registered as IsEqual resource in application XAML.
EqualityConverter Unit Tests SysManager/SysManager.Tests/EqualityConverterTests.cs	EqualityConverterTests with 8 unit tests covering Convert and ConvertBack paths: matching/non-matching strings, empty string, null value, null parameter, both null, case-sensitivity validation, and Binding.DoNothing returns.
PerformanceView Binding Integration SysManager/SysManager/Views/PerformanceView.xaml, SysManager/SysManager/Views/PerformanceView.xaml.cs	Power-plan radio buttons switched from Tag + Checked event handler to IsChecked bindings to SelectedPlan with IsEqual converter and per-button ConverterParameter values. Code-behind simplified to only InitializeComponent(); removed PropertyChanged subscription, handler, SyncRadioButtons helper, and PowerPlan_Checked event handler.
Documentation: New EqualityConverter CHANGELOG.md	Documented introduction of EqualityConverter and EqualityConverterTests in the [Unreleased] → Added section.

ProcessManagerViewModel Code Quality Refactor

Layer / File(s)	Summary
MatchesDescription ReadOnlySpan Refactor SysManager/SysManager/ViewModels/ProcessManagerViewModel.cs, CHANGELOG.md	MatchesDescription refactored from expression-bodied null-coalescing OR chain to block implementation iterating over Description, PlainDescription, and Category via ReadOnlySpan<string?>, returning true when any field contains the filter (case-insensitive). Resolves CodeQL cs/complex-condition warning. Documented in [Unreleased] → Fixed section.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• laurentiu021/SystemManager#294: Both PRs modify SysManager/SysManager/Views/PerformanceView.xaml.cs's PropertyChanged/data-context change handling—this PR removes the code-behind subscription logic in favor of XAML EqualityConverter binding, while the related PR addresses those subscription/unsubscription handlers.
• laurentiu021/SystemManager#413: Both PRs modify ProcessManagerViewModel's text-matching/filter logic with CodeQL-driven complex-condition refactoring around MatchesDescription, with overlapping changes at the same function/class level.
• laurentiu021/SystemManager#428: Both PRs modify ProcessManagerViewModel.cs by refactoring description-matching logic; this PR tightens MatchesDescription with ReadOnlySpan iteration while the related PR extracts matching into helper methods.

Poem

🐰 A converter born of binding's way,
Makes radio buttons dance in XAML's play.
No more event handlers cluttering the view,
Just equality checks through and through.
ReadOnlySpan trims complex condition's weight—
Cleaner, simpler code, and it's looking great! 🎉

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the two main changes: resolving a CodeQL complex-condition alert in ProcessManagerViewModel and fixing an MVVM violation in PerformanceView by introducing EqualityConverter.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/code-quality-mvvm

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[coderabbitai]

🧹 Nitpick comments (1)

SysManager/SysManager/Helpers/EqualityConverter.cs (1)

25-29: ⚡ Quick win

Preserve ConverterParameter type in ConvertBack return path.

At Line 28, returning parameter?.ToString() forces string conversion and weakens reusability. Return the raw parameter and short-circuit null to Binding.DoNothing.

♻️ Proposed fix

 public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
 {
     if (value is true)
-        return parameter?.ToString();
+        return parameter ?? Binding.DoNothing;
     return Binding.DoNothing;
 }

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@SysManager/SysManager/Helpers/EqualityConverter.cs` around lines 25 - 29, The
ConvertBack method currently returns parameter?.ToString(), which forces the
ConverterParameter to a string; change ConvertBack so when value is true it
returns the raw parameter object (not ToString()), and if parameter is null
return Binding.DoNothing; keep the existing behavior of returning
Binding.DoNothing when value is not true. Ensure you update the ConvertBack
method (symbol: ConvertBack) to return parameter directly and use
Binding.DoNothing as the null short-circuit.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@SysManager/SysManager/Helpers/EqualityConverter.cs`:
- Around line 25-29: The ConvertBack method currently returns
parameter?.ToString(), which forces the ConverterParameter to a string; change
ConvertBack so when value is true it returns the raw parameter object (not
ToString()), and if parameter is null return Binding.DoNothing; keep the
existing behavior of returning Binding.DoNothing when value is not true. Ensure
you update the ConvertBack method (symbol: ConvertBack) to return parameter
directly and use Binding.DoNothing as the null short-circuit.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 9c423aa3-3f70-42b7-92ec-953baf56d7b2

📥 Commits

Reviewing files that changed from the base of the PR and between 1128f28 and 7720d81.

📒 Files selected for processing (7)

• CHANGELOG.md
• SysManager/SysManager.Tests/EqualityConverterTests.cs
• SysManager/SysManager/App.xaml
• SysManager/SysManager/Helpers/EqualityConverter.cs
• SysManager/SysManager/ViewModels/ProcessManagerViewModel.cs
• SysManager/SysManager/Views/PerformanceView.xaml
• SysManager/SysManager/Views/PerformanceView.xaml.cs

💤 Files with no reviewable changes (1)

• SysManager/SysManager/Views/PerformanceView.xaml.cs

📜 Review details

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• GitHub Check: Build & unit tests
• GitHub Check: Analyze (csharp)

🔇 Additional comments (2)

SysManager/SysManager/ViewModels/ProcessManagerViewModel.cs (1)

168-177: LGTM!

SysManager/SysManager/Views/PerformanceView.xaml (1)

64-64: LGTM!

Also applies to: 68-68, 72-72