Refactor page content generators

CHDataManagement/Generator/Commands/VideoCommand.swift

@@ -0,0 +1,78 @@
+
+struct VideoCommand: CommandProcessor {
+
+    static let commandType: CommandType = .video
+
+    let content: Content
+
+    let results: PageGenerationResults
+
+    init(content: Content, results: PageGenerationResults, language: ContentLanguage) {
+        self.content = content
+        self.results = results
+    }
+
+    /**
+     Format: `![video](<fileId>;<option1...>]`
+     */
+    func process(_ arguments: [String], markdown: Substring) -> String {
+        guard arguments.count >= 1 else {
+            invalid(markdown)
+            return ""
+        }
+        let fileId = arguments[0].trimmed
+
+        let options = arguments.dropFirst().compactMap { convertVideoOption($0, markdown: markdown) }
+
+        guard let file = content.file(fileId) else {
+            results.missing(file: fileId, source: "Video command")
+            return ""
+        }
+        results.require(file: file)
+
+        guard let videoType = file.type.htmlType else {
+            invalid(markdown)
+            return ""
+        }
+
+        return ContentPageVideo(
+            filePath: file.absoluteUrl,
+            videoType: videoType,
+            options: options)
+        .content
+    }
+
+    private func convertVideoOption(_ videoOption: String, markdown: Substring) -> Option? {
+        guard let optionText = videoOption.trimmed.nonEmpty else {
+            return nil
+        }
+        guard let option = Option(rawValue: optionText) else {
+            invalid(markdown)
+            return nil
+        }
+        switch option {
+        case .poster(let imageId):
+            if let image = content.image(imageId) {
+                let width = 2 * content.settings.pages.contentWidth
+                let version = image.imageVersion(width: width, height: width, type: .jpg)
+                results.require(image: version)
+                return .poster(image: version.outputPath)
+            } else {
+                results.missing(file: imageId, source: "Video command poster")
+                return nil // Image file not present, so skip the option
+            }
+        case .src(let videoId):
+            if let video = content.video(videoId) {
+                results.used(file: video)
+                let link = video.absoluteUrl
+                return .src(link)
+            } else {
+                results.missing(file: videoId, source: "Video command source")
+                return nil // Video file not present, so skip the option
+            }
+        default:
+            return option
+        }
+    }
+
+}