Structure View Refactor & Keyboard Handling Migration

[datlechin]

Summary

Complete refactor of the Structure View to match the data grid UX and migrate keyboard handling to native responder chain patterns.

Structure View Refactor

• DataGridView Integration: Replace custom table views with DataGridView for consistent UX across data and structure tabs
• Change Tracking: Add StructureChangeManager with O(1) lookups, mirroring DataChangeManager architecture
• Visual Feedback: Yellow highlights for modifications, green for insertions, red for deletions
• Copy/Paste: Full support with custom pasteboard type to avoid conflicts with data grid
• Undo/Redo: Implemented with StructureUndoManager
• Schema Operations: SQL generation and execution for ALTER TABLE, CREATE INDEX, etc.

Keyboard Handling Migration

• Responder Chain: Replace custom ESC key system with native cancelOperation(_:)
• Standard Selectors: Use interpretKeyEvents for delete, copy, paste, undo, redo
• KeyCode Enum: Replace magic numbers with readable key codes
• Cleanup: Remove 5 EscapeKey* files (1,000+ lines of custom code eliminated)

Alert System Improvements

• AlertHelper Utility: Centralized alert dialogs with consistent styling
• Native NSAlert: Better modal behavior than SwiftUI .alert()
• Removed Components: MainContentAlerts.swift, InlineErrorBanner.swift

Performance Enhancements

• Granular Reloading: DataGridView now reloads only changed rows (was full table reload)
• Visual State Caching: Both DataChangeManager and StructureChangeManager cache row states
• Optimized Schema Loading: Pre-load all table columns (was limited to 5 tables)
• Settings Updates: Reload only visible rows for date format changes (was full table)

Bug Fixes

• Fix duplicate refresh alerts when Structure View has unsaved changes
• Fix copy/paste breaking after save (custom pasteboard type prevents conflicts)
• Remove 30+ debug print statements cluttering console output
• Add proper save confirmations before destructive operations

Testing

• ✅ Structure View: Copy/paste columns, indexes, foreign keys
• ✅ Keyboard shortcuts: Cmd+C/V/Z/Shift+Z, Delete, ESC
• ✅ Visual states: Yellow/green/red highlights for changes
• ✅ Save changes: ALTER TABLE generation and execution
• ✅ Refresh handling: Confirms before discarding unsaved changes
• ✅ DataGrid: Granular reloading for cell edits (performance improvement)
• ✅ Settings: Date format changes reload visible rows only
• ✅ Build: No warnings or errors

Architecture Notes

Change Manager Pattern

Both DataChangeManager and StructureChangeManager now follow the same O(1) pattern:

private(set) var pendingChanges: [Identifier: Change] = [:]  // O(1) lookups
private var visualStateCache: [Int: RowVisualState] = [:]     // Cached states

Responder Chain Pattern

Keyboard shortcuts now use Apple's standard responder chain:

Menu → NSApp.sendAction(#selector(copy:)) → First Responder → View handles

Custom Pasteboard Type

Structure View uses com.tablepro.structure to avoid conflicts with data grid's tab-separated format.

Files Changed

Modified: 35 files
Deleted: 6 files (EscapeKey system, old alert components)
Added: 9 files (StructureChangeManager, SchemaModels, AlertHelper, etc.)

Breaking Changes

None - all changes are internal refactoring with no API changes.

[datlechin]

@codex review

[chatgpt-codex-connector]

Codex review is not enabled for this repo. Please contact the admins of this repo to enable Codex.