External files, improve page generation

CHDataManagement/Storage/Model/Settings/PageSettingsFile.swift

@@ -4,6 +4,8 @@ struct PageSettingsFile {
     let pageUrlPrefix: String
 
     let contentWidth: Int
+
+    let largeImageWidth: Int
 }
 
 extension PageSettingsFile: Codable {
@@ -14,6 +16,7 @@ extension PageSettingsFile {
 
     static var `default`: PageSettingsFile {
         .init(pageUrlPrefix: "page",
-              contentWidth: 600)
+              contentWidth: 600,
+              largeImageWidth: 1200)
     }
 }

CHDataManagement/Storage/Storage.swift

@@ -379,6 +379,18 @@ final class Storage {
         return try readExistingFile(at: path)
     }
 
+    // MARK: External file list
+
+    private let externalFileListName = "external-files.json"
+
+    func loadExternalFileList() throws -> [String] {
+        try read(at: externalFileListName, defaultValue: [])
+    }
+
+    func save(externalFileList: [String]) throws {
+        try writeIfChanged(externalFileList.sorted(), to: externalFileListName)
+    }
+
     // MARK: Website data
 
     private let settingsDataFileName: String = "settings.json"