Started work on the reformatting guide

Author: austincondiff

Sources/CodeEditSourceEditor/Controller/TextViewController+LoadView.swift

@@ -31,6 +31,10 @@ extension TextViewController {
         minimapView = MinimapView(textView: textView, theme: theme)
         scrollView.addFloatingSubview(minimapView, for: .vertical)
 
+        // Add reformatting guide view
+        let guideView = ReformattingGuideView(frame: NSRect(x: 0, y: 0, width: 100, height: 100))
+        textView.addSubview(guideView)
+
         let findViewController = FindViewController(target: self, childView: scrollView)
         addChild(findViewController)
         self.findViewController = findViewController

Sources/CodeEditSourceEditor/Controller/TextViewController+ReloadUI.swift

@@ -19,5 +19,10 @@ extension TextViewController {
         highlighter?.invalidate()
         minimapView.updateContentViewHeight()
         minimapView.updateDocumentVisibleViewPosition()
+        
+        // Update reformatting guide position
+        if let guideView = textView.subviews.first(where: { $0 is ReformattingGuideView }) as? ReformattingGuideView {
+            guideView.updatePosition(in: textView)
+        }
     }
 }

Sources/CodeEditSourceEditor/ReformattingGuide/ReformattingGuideView.swift

@@ -0,0 +1,95 @@
+import AppKit
+import CodeEditTextView
+
+class ReformattingGuideView: NSView {
+    private let column: Int = 80
+
+    override init(frame frameRect: NSRect) {
+        super.init(frame: frameRect)
+        wantsLayer = true
+        print("ReformattingGuideView initialized with frame: \(frameRect)")
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    override func draw(_ dirtyRect: NSRect) {
+        super.draw(dirtyRect)
+        print("Drawing guide view with frame: \(frame)")
+
+        // For debugging, make the guide more visible
+        NSColor.red.withAlphaComponent(0.3).setFill()
+        frame.fill()
+
+        // Draw a border around the guide for better visibility
+        NSColor.blue.setStroke()
+        let borderPath = NSBezierPath(rect: frame)
+        borderPath.lineWidth = 2.0
+        borderPath.stroke()
+
+        // Get the current theme's background color to determine if we're in light or dark mode
+        let isLightMode = NSApp.effectiveAppearance.name == .aqua
+
+        // Set the line color based on the theme
+        let lineColor = isLightMode ?
+            NSColor.black.withAlphaComponent(0.1) :
+            NSColor.white.withAlphaComponent(0.1)
+
+        // Set the shaded area color (slightly more transparent)
+        let shadedColor = isLightMode ?
+            NSColor.black.withAlphaComponent(0.05) :
+            NSColor.white.withAlphaComponent(0.05)
+
+        // Draw the vertical line (accounting for inverted Y coordinate system)
+        lineColor.setStroke()
+        let linePath = NSBezierPath()
+        linePath.move(to: NSPoint(x: frame.minX, y: frame.maxY))  // Start at top
+        linePath.line(to: NSPoint(x: frame.minX, y: frame.minY))  // Draw down to bottom
+        linePath.lineWidth = 1.0
+        linePath.stroke()
+
+        // Draw the shaded area to the right of the line
+        shadedColor.setFill()
+        let shadedRect = NSRect(
+            x: frame.minX,
+            y: frame.minY,
+            width: frame.width,
+            height: frame.height
+        )
+        shadedRect.fill()
+    }
+
+    func updatePosition(in textView: TextView) {
+        // Wait for the text view to have a valid width
+        guard textView.frame.width > 0 else {
+            print("Text view width is 0, skipping position update")
+            return
+        }
+
+        // Calculate the x position based on the font's character width and column number
+        let charWidth = textView.font.boundingRectForFont.width
+        let xPosition = CGFloat(column) * charWidth
+
+        print("Updating guide position:")
+        print("- Character width: \(charWidth)")
+        print("- Target column: \(column)")
+        print("- Calculated x position: \(xPosition)")
+        print("- Text view width: \(textView.frame.width)")
+
+        // Ensure we don't create an invalid frame
+        let maxWidth = max(0, textView.frame.width - xPosition/2)
+
+        // Update the frame to be a vertical line at column 80 with a shaded area to the right
+        let newFrame = NSRect(
+            x: 200,
+            y: 0,
+            width: maxWidth,
+            height: textView.frame.height
+        )
+        print("Setting new frame: \(newFrame)")
+
+        frame = newFrame
+        needsDisplay = true
+    }
+}