feat: export notes as portable Markdown

Sources/Conjure/ApplicationActionsController.swift

@@ -37,6 +37,8 @@ final class ApplicationActionsController: NSViewController, NSSearchFieldDelegat
     var browseNotes: (() -> Void)?
     var newNote: (() -> Void)?
     var deleteNote: (() -> Void)?
+    var copyNoteMarkdown: (() -> Void)?
+    var exportNoteMarkdown: (() -> Void)?
     private enum ChoiceID: Equatable {
         case language(String)
         case note(UUID)
@@ -86,7 +88,9 @@ final class ApplicationActionsController: NSViewController, NSSearchFieldDelegat
             ActionEntry(title: "OpenAI · gpt-6-luna", symbol: "checkmark", color: SunsetPalette.text),
             ActionEntry(title: "Browse Notes", symbol: "list.bullet", color: SunsetPalette.text, commandKey: "P"),
             ActionEntry(title: "New Note", symbol: "square.and.pencil", color: SunsetPalette.text, commandKey: "N"),
-            ActionEntry(title: "Delete Note", symbol: "trash", color: .systemRed)
+            ActionEntry(title: "Delete Note", symbol: "trash", color: .systemRed),
+            ActionEntry(title: "Copy as Markdown", symbol: "doc.on.doc", color: SunsetPalette.text),
+            ActionEntry(title: "Export as Markdown…", symbol: "square.and.arrow.up", color: SunsetPalette.text)
         ]
         view = ActionsPanelView()
         view.wantsLayer = true
@@ -259,7 +263,7 @@ final class ApplicationActionsController: NSViewController, NSSearchFieldDelegat
     }
 
     func showNotesActions(relativeTo anchor: NSView) {
-        show(title: "Notes", relativeTo: anchor, available: [12, 13, 14],
+        show(title: "Notes", relativeTo: anchor, available: [12, 13, 14, 15, 16],
              searchAccessibilityLabel: "Search notes actions")
     }
 
@@ -466,7 +470,7 @@ final class ApplicationActionsController: NSViewController, NSSearchFieldDelegat
     }
 
     private func handleCommandKey(_ key: String) -> Bool {
-        guard isShown, availableEntries == [12, 13, 14] else { return false }
+        guard isShown, availableEntries == [12, 13, 14, 15, 16] else { return false }
         switch key {
         case "p": close(); browseNotes?()
         case "n": close(); newNote?()
@@ -540,6 +544,8 @@ final class ApplicationActionsController: NSViewController, NSSearchFieldDelegat
         case 12: browseNotes?()
         case 13: newNote?()
         case 14: deleteNote?()
+        case 15: copyNoteMarkdown?()
+        case 16: exportNoteMarkdown?()
         default: break
         }
     }

Sources/Conjure/NotesController.swift

@@ -1,6 +1,7 @@
 import AppKit
 import ConjureKit
 import Highlighter
+import UniformTypeIdentifiers
 
 @MainActor
 enum NotesAppearance {
@@ -77,6 +78,8 @@ final class NotesController: NSViewController, NSTextViewDelegate {
         actions.newNote = { [weak self] in self?.newNote() }
         actions.browseNotes = { [weak self] in self?.browseNotes() }
         actions.deleteNote = { [weak self] in self?.deleteNote() }
+        actions.copyNoteMarkdown = { [weak self] in self?.copyAsMarkdown() }
+        actions.exportNoteMarkdown = { [weak self] in self?.exportAsMarkdown() }
         let tools = [
             ("textformat.size", "Heading"), ("bold", "Bold"), ("italic", "Italic"),
             ("strikethrough", "Strikethrough"), ("chevron.left.forwardslash.chevron.right", "Inline code"),
@@ -534,6 +537,51 @@ final class NotesController: NSViewController, NSTextViewDelegate {
         catch { showError(error) }
     }
 
+    private func copyAsMarkdown() {
+        actions.close(animated: false)
+        do {
+            let export = try NoteMarkdownExport(contents: editor.markdownContents)
+            let clipboard = NSPasteboard.general
+            clipboard.clearContents()
+            guard clipboard.setString(export.clipboardText, forType: .string) else {
+                throw CocoaError(.fileWriteUnknown)
+            }
+        } catch { showExportError(error) }
+    }
+
+    private func exportAsMarkdown() {
+        guard let window = view.window, window.attachedSheet == nil else { return }
+        actions.close(animated: false)
+        do {
+            let export = try NoteMarkdownExport(contents: editor.markdownContents)
+            let panel = NSSavePanel()
+            panel.title = "Export as Markdown"
+            panel.prompt = "Export"
+            panel.canCreateDirectories = true
+            panel.nameFieldStringValue = export.hasImages ? "Note" : "Note.md"
+            if export.hasImages {
+                panel.message = "Create a new folder containing note.md and its images. Choose a folder name that does not already exist."
+            } else {
+                panel.allowedContentTypes = [UTType(filenameExtension: "md") ?? .plainText]
+            }
+            panel.beginSheetModal(for: window) { [weak self] response in
+                guard let self else { return }
+                defer { self.focusEditor() }
+                guard response == .OK, let url = panel.url else { return }
+                do { try export.write(to: url) }
+                catch { self.showExportError(error) }
+            }
+        } catch { showExportError(error) }
+    }
+
+    private func showExportError(_ error: Error) {
+        status.isHidden = false
+        status.stringValue = "Couldn’t export note: \(error.localizedDescription)"
+        status.toolTip = status.stringValue
+        status.textColor = .systemRed
+    }
+
+
     private func deleteNote() {
         guard let window = view.window, window.attachedSheet == nil, let id = selectedID else { return }
         actions.close(animated: false)

Sources/ConjureKit/NoteMarkdownExport.swift

@@ -0,0 +1,135 @@
+import AppKit
+import ImageIO
+import UniformTypeIdentifiers
+
+@MainActor
+public struct NoteMarkdownExport {
+    public let clipboardText: String
+    public var hasImages: Bool { !images.isEmpty }
+    private let markdown: String
+    private let images: [(name: String, data: Data)]
+
+    public init(contents: NSAttributedString) throws {
+        let source = contents.string as NSString
+        var markdown = ""
+        var clipboard = ""
+        var images: [(name: String, data: Data)] = []
+        var usedNames: Set<String> = ["note.md"]
+        var cursor = 0
+        while cursor < source.length {
+            let range = source.range(of: "\u{fffc}", options: [], range: NSRange(location: cursor, length: source.length - cursor))
+            let end = range.location == NSNotFound ? source.length : range.location
+            let text = source.substring(with: NSRange(location: cursor, length: end - cursor))
+            markdown += text
+            clipboard += text
+            guard range.location != NSNotFound else { break }
+            if let value = contents.attribute(.attachment, at: range.location, effectiveRange: nil) {
+                guard let attachment = value as? NSTextAttachment else { throw ExportError.unreadableAttachment }
+                let (data, type) = try Self.imageData(attachment)
+                let originalName = attachment.fileWrapper?.preferredFilename ?? attachment.fileWrapper?.filename
+                let name = try Self.filename(originalName, type: type, index: images.count + 1, used: &usedNames)
+                var alt = ""
+                var ticks = 0
+                var longestTicks = 0
+                for character in name {
+                    if "\\[]`*_<>!&".contains(character) { alt += "\\" }
+                    alt.append(character)
+                    ticks = character == "`" ? ticks + 1 : 0
+                    longestTicks = max(longestTicks, ticks)
+                }
+                guard let target = name.addingPercentEncoding(withAllowedCharacters: Self.linkCharacters) else {
+                    throw ExportError.unreadableAttachment
+                }
+                markdown += "![\(alt)](\(target))"
+                let fence = String(repeating: "`", count: longestTicks + 1)
+                clipboard += "\(fence)<\(name)>\(fence)"
+                images.append((name, data))
+            } else {
+                markdown += "\u{fffc}"
+                clipboard += "\u{fffc}"
+            }
+            cursor = NSMaxRange(range)
+        }
+        self.markdown = markdown
+        clipboardText = clipboard
+        self.images = images
+    }
+
+    public func write(to url: URL) throws {
+        guard hasImages else {
+            try markdown.write(to: url, atomically: true, encoding: .utf8)
+            return
+        }
+        let manager = FileManager.default
+        guard !manager.fileExists(atPath: url.path) else {
+            throw CocoaError(.fileWriteFileExists, userInfo: [NSFilePathErrorKey: url.path])
+        }
+        let staging = url.deletingLastPathComponent().appendingPathComponent(".conjure-export-\(UUID().uuidString)", isDirectory: true)
+        try manager.createDirectory(at: staging, withIntermediateDirectories: false)
+        defer { try? manager.removeItem(at: staging) }
+        try markdown.write(to: staging.appendingPathComponent("note.md"), atomically: false, encoding: .utf8)
+        for image in images {
+            try image.data.write(to: staging.appendingPathComponent(image.name))
+        }
+        try manager.moveItem(at: staging, to: url)
+    }
+
+    private static func imageData(_ attachment: NSTextAttachment) throws -> (Data, UTType) {
+        if let wrapper = attachment.fileWrapper {
+            guard wrapper.isRegularFile, let data = wrapper.regularFileContents,
+                  let source = CGImageSourceCreateWithData(data as CFData, nil),
+                  let identifier = CGImageSourceGetType(source),
+                  let type = UTType(identifier as String), type.conforms(to: .image),
+                  CGImageSourceCreateImageAtIndex(source, 0, nil) != nil else {
+                throw ExportError.unreadableAttachment
+            }
+            return (data, type)
+        }
+        guard let image = attachment.image ?? (attachment.attachmentCell as? NSTextAttachmentCell)?.image,
+              let cgImage = image.cgImage(forProposedRect: nil, context: nil, hints: nil),
+              let png = NSBitmapImageRep(cgImage: cgImage).representation(using: .png, properties: [:]) else {
+            throw ExportError.unreadableAttachment
+        }
+        return (png, .png)
+    }
+
+    private static func filename(_ original: String?, type: UTType, index: Int, used: inout Set<String>) throws -> String {
+        guard let detectedExtension = type.preferredFilenameExtension else { throw ExportError.unreadableAttachment }
+        var stem = "image-\(index)"
+        var ext = detectedExtension
+        if let original, isSafeFilename(original) {
+            let path = original as NSString
+            stem = path.deletingPathExtension
+            if UTType(filenameExtension: path.pathExtension) == type { ext = path.pathExtension }
+        }
+        var name = "\(stem).\(ext)"
+        var suffix = 2
+        while !used.insert(name.folding(options: .caseInsensitive, locale: Self.filenameLocale)).inserted {
+            name = "\(stem)-\(suffix).\(ext)"
+            suffix += 1
+        }
+        return name
+    }
+
+    private static let linkCharacters = CharacterSet(charactersIn: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~")
+    private static let reservedNames = Set(["con", "prn", "aux", "nul"] + (1...9).flatMap { ["com\($0)", "lpt\($0)"] })
+    private static let filenameLocale = Locale(identifier: "en_US_POSIX")
+
+    private static func isSafeFilename(_ name: String) -> Bool {
+        guard !name.isEmpty, name.utf8.count <= 180,
+              !name.hasPrefix("."), !name.hasSuffix("."),
+              name == name.trimmingCharacters(in: .whitespacesAndNewlines),
+              name.rangeOfCharacter(from: .controlCharacters) == nil,
+              !name.contains("/"), !name.contains("\\"), !name.contains(":") else { return false }
+        let stem = (name as NSString).deletingPathExtension.lowercased()
+        return !reservedNames.contains(stem)
+    }
+
+    private enum ExportError: LocalizedError {
+        case unreadableAttachment
+
+        var errorDescription: String? {
+            "This note contains an unsupported or unreadable image attachment. Nothing was exported."
+        }
+    }
+}