Add page id feature

WebsiteGenerator/Content/Element.swift

@@ -255,6 +255,20 @@ struct Element {
 
 extension Element {
 
+    /**
+     The localized html file name for a language, including a leading slash.
+     */
+    static func htmlPagePathAddition(for language: String) -> String {
+        "/" + htmlPageName(for: language)
+    }
+
+    /**
+     The localized html file name for a language, without the leading slash.
+     */
+    static func htmlPageName(for language: String) -> String {
+        "\(language).html"
+    }
+
     var containsElements: Bool {
         !elements.isEmpty
     }
@@ -286,7 +300,30 @@ extension Element {
      The url of the top-level section of the element.
      */
     func sectionUrl(for language: String) -> String {
-        path.components(separatedBy: "/").first! + "/\(language).html"
+        path.components(separatedBy: "/").first! + Element.htmlPagePathAddition(for: language)
+    }
+
+    /**
+     Create a relative link to another page in the tree.
+     - Parameter pageUrl: The full page url of the target page, including localization
+     - Returns: The relative url from a localized page of the element to the target page.
+     */
+    func relativePathToOtherSiteElement(pageUrl: String) -> String {
+        // Note: The element `path` is missing the last component
+        // i.e. travel/alps instead of travel/alps/en.html
+        let ownParts = path.components(separatedBy: "/")
+        let pageParts = pageUrl.components(separatedBy: "/")
+
+        // Find the common elements of the path, which can be discarded
+        var index = 0
+        while pageParts[index] == ownParts[index] {
+            index += 1
+        }
+        // The relative path needs to go down to the first common folder,
+        // before going up to the target page
+        let allParts = [String](repeating: "..", count: ownParts.count-index)
+                        + pageParts.dropFirst(index)
+        return allParts.joined(separator: "/")
     }
     
     /**
@@ -381,7 +418,10 @@ extension Element {
      Returns the full path (relative to the site root for a page of the element in the given language.
      */
     func localizedPath(for language: String) -> String {
-        path != "" ? "\(path)/\(language).html" : "\(language).html"
+        guard path != "" else {
+            return Element.htmlPageName(for: language)
+        }
+        return path + Element.htmlPagePathAddition(for: language)
     }
 
     /**

WebsiteGenerator/Files/FileSystem.swift

@@ -440,6 +440,10 @@ final class FileSystem {
         pagePaths[id] = page
     }
 
+    func getPage(for id: String) -> String? {
+        pagePaths[id]
+    }
+
 
     // MARK: Writing files
 

WebsiteGenerator/Generators/HTMLElementsGenerator.swift

@@ -12,11 +12,11 @@ struct HTMLElementsGenerator {
 
     // - TODO: Make link relative
     func topBarWebsiteTitle(language: String) -> String {
-        "/\(language).html"
+        Element.htmlPagePathAddition(for: language)
     }
 
     func topBarLanguageButton(_ language: String) -> String {
-        "<a href=\"\(language).html\">\(language)</a>"
+        "<a href=\"\(Element.htmlPageName(for: language))\">\(language)</a>"
     }
 
     func topBarNavigationLink(url: String, text: String, isActive: Bool) -> String {
@@ -46,7 +46,7 @@ struct HTMLElementsGenerator {
     func svgImage(file: String, x: Int, y: Int, width: Int, height: Int) -> String {
         """
         <span class="image">
-            <img src="\(file)#svgView(viewBox(\(x), \(y), \(width), \(height))" style="aspect-ratio:\(Float(width)/Float(height))"/>
+            <img src="\(file)#svgView(viewBox(\(x), \(y), \(width), \(height)))" style="aspect-ratio:\(Float(width)/Float(height))"/>
         </span>
         """
     }

WebsiteGenerator/Generators/MarkdownProcessor.swift

@@ -27,27 +27,49 @@ struct PageContentGenerator {
             return html
         }
         let linkModifier = Modifier(target: .links) { html, markdown in
+            handleLink(page: page, language: language, html: html, markdown: markdown)
+        }
+        let htmlModifier = Modifier(target: .html) { html, markdown in
+            handleHTML(page: page, language: language, html: html, markdown: markdown)
+        }
+
+        let parser = MarkdownParser(modifiers: [imageModifier, codeModifier, linkModifier, htmlModifier])
+        return (parser.html(from: content), hasCodeContent)
+    }
+
+    private func handleLink(page: Element, language: String, html: String, markdown: Substring) -> String {
         let file = markdown.between("(", and: ")")
+        if file.hasPrefix("page:") {
+            let pageId = file.replacingOccurrences(of: "page:", with: "")
+            guard let pagePath = files.getPage(for: pageId) else {
+                log.add(warning: "Page id '\(pageId)' not found", source: page.path)
+                // Remove link since the page can't be found
+                return markdown.between("[", and: "]")
+            }
+            let fullPath = pagePath + Element.htmlPagePathAddition(for: language)
+            // Adjust file path to get the page url
+            let url = page.relativePathToOtherSiteElement(pageUrl: fullPath)
+            return html.replacingOccurrences(of: file, with: url)
+        }
+
         if let filePath = page.nonAbsolutePathRelativeToRootForContainedInputFile(file) {
             // The target of the page link must be present after generation is complete
             files.expect(file: filePath, source: page.path)
         }
         return html
     }
-        let htmlModifier = Modifier(target: .html) { html, markdown in
+
+    private func handleHTML(page: Element, language: String, html: String, markdown: Substring) -> String {
+        #warning("Check HTML code in markdown for required resources")
         //print("[HTML] Found in page \(page.path):")
         //print(markdown)
-            // Thinks to check
+        // Things to check:
         // <img src=
         // <a href=
         //
         return html
     }
 
-        let parser = MarkdownParser(modifiers: [imageModifier, codeModifier, linkModifier, htmlModifier])
-        return (parser.html(from: content), hasCodeContent)
-    }
-
     private func processMarkdownImage(markdown: Substring, html: String, page: Element) -> String {
         // Split the markdown ![alt](file title)
         // For images: ![left_title](file right_title)
@@ -127,7 +149,7 @@ struct PageContentGenerator {
         guard let area = area else {
             return factory.html.svgImage(file: file)
         }
-        let parts = area.components(separatedBy: ",")
+        let parts = area.components(separatedBy: ",").map { $0.trimmed }
         guard parts.count == 4,
               let x = Int(parts[0]),
               let y = Int(parts[1]),

WebsiteGenerator/Templates/Filled/LocalizedSiteTemplate.swift

@@ -58,7 +58,7 @@ struct LocalizedSiteTemplate {
         let sections = site.sortedItems.map {
             PrefilledTopBarTemplate.SectionInfo(
                 name: $0.title(for: language),
-                url: "\($0.path)/\(language).html")
+                url: $0.path + Element.htmlPagePathAddition(for: language))
         }
 
         self.topBar = try .init(
@@ -83,7 +83,7 @@ struct LocalizedSiteTemplate {
     func makeBackLink(text: String, language: String) -> String {
         let content: [BackNavigationTemplate.Key : String] = [
             .text: text,
-            .url: "../\(language).html"
+            .url: ".." + Element.htmlPagePathAddition(for: language)
         ]
         return backNavigation.generate(content)
     }