1 files changed, 42 insertions, 0 deletions
diff --git a/Map/Data/MapDocument.swift b/Map/Data/MapDocument.swift
new file mode 100644
index 0000000..9340684
--- /dev/null
+++ b/Map/Data/MapDocument.swift
@@ -0,0 +1,42 @@
+import SwiftUI
+import UniformTypeIdentifiers
+
+extension UTType {
+  static var exampleText: UTType {
+    UTType(importedAs: "systems.tranquil.map.wmap")
+  }
+}
+
+struct MapDocument: FileDocument {
+  var text: String
+
+  init(text: String = "Hello, world!") {
+    self.text = text
+  }
+
+  static var readableContentTypes: [UTType] { [.exampleText] }
+
+  init(configuration: ReadConfiguration) throws {
+    guard let data = configuration.file.regularFileContents,
+      let string = String(data: data, encoding: .utf8)
+    else {
+      throw CocoaError(.fileReadCorruptFile)
+    }
+    text = string
+  }
+
+  func fileWrapper(configuration: WriteConfiguration) throws -> FileWrapper {
+    let data = text.data(using: .utf8)!
+    return .init(regularFileWithContents: data)
+  }
+
+  @MainActor
+  func exportAsImage(withEvolution selectedEvolution: StageType) -> NSImage? {
+    let renderView = MapRenderView(
+      document: .constant(self),
+      evolution: .constant(selectedEvolution))
+    let renderer = ImageRenderer(content: renderView)
+
+    return renderer.nsImage
+  }
+}