Feat: Add a blog configuration with yaml

- Add input config, who allow to define the path import
- Add output config, who allow to define the path destination
- Add hidden, who allow to not generate the blog

Author: Dedelweiss

scaladoc/src/dotty/tools/scaladoc/site/StaticSiteContext.scala

@@ -23,6 +23,10 @@ class StaticSiteContext(
   val docsPath = root.toPath.resolve("_docs")
   val blogPath = root.toPath.resolve("_blog")
 
+  def resolveNewBlogPath(stringPath: String): Path =
+    if stringPath.nonEmpty then root.toPath.resolve(stringPath)
+    else blogPath
+
   def relativize(path: Path): Path =
     if args.apiSubdirectory then
       docsPath.relativize(path)

scaladoc/src/dotty/tools/scaladoc/site/StaticSiteLoader.scala

@@ -113,11 +113,42 @@ class StaticSiteLoader(val root: File, val args: Scaladoc.Args)(using StaticSite
     StaticSiteRoot(withBlog, mappings)
   }
 
+  var hiddenBlog = false
+
+  def readYml: (Option[Boolean], Option[Boolean], Option[Boolean], String) =
+    val ymlPath = root.toPath.resolve("blog.yml")
+    if (Files.exists(ymlPath)) then
+      val yamlContent = Source.fromFile(ymlPath.toString).getLines().mkString("\n")
+      val hidden = if (yamlContent.contains("hidden: true")) Some(true) else None
+      val input = if (yamlContent.contains("input:")) Some(true) else None
+      val output = if (yamlContent.contains("output:")) Some(true) else None
+      (hidden, input, output, yamlContent)
+    else
+      (None, None, None, "")
+
   def loadBlog(): Option[LoadedTemplate] = {
+    val (hidden, input, output, yamlContent) = readYml
+    val lines = yamlContent.split("\n")
+    val rootPath = input.collect {
+      case true =>
+        lines.collectFirst { case line if line.contains("input:") => line.replaceFirst("input:", "").trim }
+          .map(ctx.resolveNewBlogPath)
+          .getOrElse(ctx.blogPath)
+    }.getOrElse(ctx.blogPath)
+    val defaultDirectory = output.collect {
+    case true =>
+      lines
+        .collectFirst { case line if line.contains("output:") => line.replaceFirst("output:", "").trim }
+        .getOrElse("blog")
+    }.getOrElse("blog")
+    hidden.collect { case true => hiddenBlog = true }
     type Date = (String, String, String)
-    val rootPath = ctx.blogPath
-    val defaultDirectory = "blog"
-    if (!Files.exists(rootPath)) None
+    if (!Files.exists(rootPath))
+      report.warning(s"Blog directory $rootPath does not exist.")
+      None
+    else if(hiddenBlog) then
+      report.warning(s"Blog is hidden")
+      None
     else {
       val indexPageOpt = Seq(
           rootPath.resolve("index.md"),