src/Pure/Thy/presentation.scala

clarified signature;

/*  Title:      Pure/Thy/presentation.scala
    Author:     Makarius

HTML presentation of PIDE document content.
*/

package isabelle


import scala.annotation.tailrec
import scala.collection.immutable.SortedMap
import scala.collection.mutable


object Presentation {
  /** HTML documents **/

  /* HTML context */

  sealed case class HTML_Document(title: String, content: String)

  abstract class HTML_Context {
    /* directory structure and resources */

    def nodes: Nodes
    def root_dir: Path
    def theory_session(name: Document.Node.Name): Sessions.Info

    def session_dir(info: Sessions.Info): Path =
      root_dir + Path.explode(info.chapter_session)
    def theory_dir(name: Document.Node.Name): Path =
      session_dir(theory_session(name))
    def files_path(name: Document.Node.Name, path: Path): Path =
      theory_dir(name) + Path.explode("files") + path.squash.html


    /* HTML content */

    def head(title: String, rest: XML.Body = Nil): XML.Tree =
      HTML.div("head", HTML.chapter(title) :: rest)

    def source(body: XML.Body): XML.Tree = HTML.pre("source", body)

    def contents(
      heading: String,
      items: List[XML.Body],
      css_class: String = "contents"
    ) : List[XML.Elem] = {
      if (items.isEmpty) Nil
      else List(HTML.div(css_class, List(HTML.section(heading), HTML.itemize(items))))
    }

    val isabelle_css: String = File.read(HTML.isabelle_css)

    def html_document(title: String, body: XML.Body, fonts_css: String): HTML_Document = {
      val content =
        HTML.output_document(
          List(
            HTML.style(fonts_css + "\n\n" + isabelle_css),
            HTML.title(title)),
          List(HTML.source(body)), css = "", structural = false)
      HTML_Document(title, content)
    }
  }


  /* presentation elements */

  sealed case class Elements(
    html: Markup.Elements = Markup.Elements.empty,
    entity: Markup.Elements = Markup.Elements.empty,
    language: Markup.Elements = Markup.Elements.empty)

  val elements1: Elements =
    Elements(
      html = Rendering.foreground_elements ++ Rendering.text_color_elements +
        Markup.NUMERAL + Markup.COMMENT + Markup.ENTITY + Markup.LANGUAGE,
      entity = Markup.Elements(Markup.THEORY, Markup.TYPE_NAME, Markup.CONSTANT, Markup.FACT,
        Markup.CLASS, Markup.LOCALE, Markup.FREE))

  val elements2: Elements =
    Elements(
      html = elements1.html ++ Rendering.markdown_elements,
      language = Markup.Elements(Markup.Language.DOCUMENT))


  /* per-session node info */

  object Node_Info {
    val empty: Node_Info = new Node_Info(Map.empty, Map.empty, Nil)
    def make(theory: Export_Theory.Theory): Node_Info = {
      val by_range = theory.entity_iterator.toList.groupBy(_.range)
      val by_kind_name =
        theory.entity_iterator.map(entity => ((entity.kind, entity.name), entity)).toMap
      val others = theory.others.keySet.toList
      new Node_Info(by_range, by_kind_name, others)
    }
  }

  class Node_Info private(
    by_range: Map[Symbol.Range, List[Export_Theory.Entity0]],
    by_kind_name: Map[(String, String), Export_Theory.Entity0],
    val others: List[String]) {
    def for_range(range: Symbol.Range): List[Export_Theory.Entity0] =
      by_range.getOrElse(range, Nil)
    def get_kind_name(kind: String, name: String): Option[String] =
      by_kind_name.get((kind, name)).map(_.kname)
  }

  object Nodes {
    val empty: Nodes = new Nodes(Map.empty)

    def read(
      presentation_sessions: List[String],
      deps: Sessions.Deps,
      db_context: Sessions.Database_Context
    ): Nodes = {
      type Batch = (String, List[String])
      val batches =
        presentation_sessions.foldLeft((Set.empty[String], List.empty[Batch]))(
          { case ((seen, batches), session) =>
              val thys = deps(session).loaded_theories.keys.filterNot(seen)
              (seen ++ thys, (session, thys) :: batches)
          })._2
      val theory_node_info =
        Par_List.map[Batch, List[(String, Node_Info)]](
          { case (session, thys) =>
              db_context.database(session) { db =>
                val provider = Export.Provider.database(db, db_context.cache, session)
                val result =
                  for (thy_name <- thys) yield {
                    val theory =
                      if (thy_name == Thy_Header.PURE) Export_Theory.no_theory
                      else {
                        Export_Theory.read_theory(provider, session, thy_name,
                          permissive = true, cache = db_context.cache)
                      }
                    thy_name -> Node_Info.make(theory)
                  }
                Some(result)
              } getOrElse Nil
          }, batches).flatten.toMap
      new Nodes(theory_node_info)
    }
  }

  class Nodes private(theory_node_info: Map[String, Node_Info]) {
    def apply(name: String): Node_Info = theory_node_info.getOrElse(name, Node_Info.empty)
    def get(name: String): Option[Node_Info] = theory_node_info.get(name)
  }


  /* formal entities */

  type Entity = Export_Theory.Entity[Export_Theory.No_Content]

  object Entity_Context {
    object Theory_Ref {
      def unapply(props: Properties.T): Option[Document.Node.Name] =
        (props, props, props) match {
          case (Markup.Kind(Markup.THEORY), Markup.Name(theory), Position.Def_File(thy_file)) =>
            Some(Resources.file_node(Path.explode(thy_file), theory = theory))
          case _ => None
        }
    }

    object Entity_Ref {
      def unapply(props: Properties.T): Option[(Path, Option[String], String, String)] =
        (props, props, props, props) match {
          case (Markup.Entity.Ref.Prop(_), Position.Def_File(def_file),
              Markup.Kind(kind), Markup.Name(name)) =>
            val def_theory = Position.Def_Theory.unapply(props)
            Some((Path.explode(def_file), def_theory, kind, name))
          case _ => None
        }
    }

    val empty: Entity_Context = new Entity_Context

    def make(
        session: String,
        deps: Sessions.Deps,
        node: Document.Node.Name,
        html_context: HTML_Context): Entity_Context =
      new Entity_Context {
        private val seen_ranges: mutable.Set[Symbol.Range] = mutable.Set.empty

        override def make_def(range: Symbol.Range, body: XML.Body): Option[XML.Elem] = {
          body match {
            case List(XML.Elem(Markup("span", List("id" -> _)), _)) => None
            case _ =>
              Some {
                val entities = html_context.nodes(node.theory).for_range(range)
                val body1 =
                  if (seen_ranges.contains(range)) {
                    HTML.entity_def(HTML.span(HTML.id(offset_id(range)), body))
                  }
                  else HTML.span(body)
                entities.map(_.kname).foldLeft(body1) {
                  case (elem, id) => HTML.entity_def(HTML.span(HTML.id(id), List(elem)))
                }
              }
          }
        }

        private def offset_id(range: Text.Range): String =
          "offset_" + range.start + ".." + range.stop

        private def physical_ref(thy_name: String, props: Properties.T): Option[String] = {
          for {
            range <- Position.Def_Range.unapply(props)
            if thy_name == node.theory
          } yield {
            seen_ranges += range
            offset_id(range)
          }
        }

        private def logical_ref(thy_name: String, kind: String, name: String): Option[String] =
          html_context.nodes.get(thy_name).flatMap(_.get_kind_name(kind, name))

        override def make_ref(props: Properties.T, body: XML.Body): Option[XML.Elem] = {
          props match {
            case Theory_Ref(node_name) =>
              node_relative(deps, session, node_name).map(html_dir =>
                HTML.link(html_dir + html_name(node_name), body))
            case Entity_Ref(file_path, def_theory, kind, name) if file_path.get_ext == "thy" =>
              for {
                thy_name <-
                  def_theory orElse (if (File.eq(node.path, file_path)) Some(node.theory) else None)
                node_name = Resources.file_node(file_path, theory = thy_name)
                html_dir <- node_relative(deps, session, node_name)
                html_file = node_file(node_name)
                html_ref <-
                  logical_ref(thy_name, kind, name) orElse physical_ref(thy_name, props)
              } yield {
                HTML.entity_ref(HTML.link(html_dir + html_file + "#" + html_ref, body))
              }
            case _ => None
          }
        }
      }
  }

  class Entity_Context {
    def make_def(range: Symbol.Range, body: XML.Body): Option[XML.Elem] = None
    def make_ref(props: Properties.T, body: XML.Body): Option[XML.Elem] = None
  }


  /* HTML output */

  private val div_elements =
    Set(HTML.div.name, HTML.pre.name, HTML.par.name, HTML.list.name, HTML.`enum`.name,
      HTML.descr.name)

  def make_html(
    entity_context: Entity_Context,
    elements: Elements,
    xml: XML.Body
  ): XML.Body = {
    def html_div(html: XML.Body): Boolean =
      html exists {
        case XML.Elem(markup, body) => div_elements.contains(markup.name) || html_div(body)
        case XML.Text(_) => false
      }

    def html_class(c: String, html: XML.Body): XML.Body =
      if (c == "") html
      else if (html_div(html)) List(HTML.div(c, html))
      else List(HTML.span(c, html))

    def html_body(xml_body: XML.Body, end_offset: Symbol.Offset): (XML.Body, Symbol.Offset) =
      xml_body.foldRight((List.empty[XML.Tree], end_offset)) { case (tree, (res, end_offset1)) =>
        val (res1, offset) = html_body_single(tree, end_offset1)
        (res1 ++ res, offset)
      }

    @tailrec
    def html_body_single(xml_tree: XML.Tree, end_offset: Symbol.Offset): (XML.Body, Symbol.Offset) =
      xml_tree match {
        case XML.Wrapped_Elem(markup, _, body) => html_body_single(XML.Elem(markup, body), end_offset)
        case XML.Elem(Markup(Markup.ENTITY, props @ Markup.Kind(kind)), body) =>
          val (body1, offset) = html_body(body, end_offset)
          if (elements.entity(kind)) {
            entity_context.make_ref(props, body1) match {
              case Some(link) => (List(link), offset)
              case None => (body1, offset)
            }
          }
          else (body1, offset)
        case XML.Elem(Markup(Markup.LANGUAGE, Markup.Name(name)), body) =>
          val (body1, offset) = html_body(body, end_offset)
          (html_class(if (elements.language(name)) name else "", body1), offset)
        case XML.Elem(Markup(Markup.MARKDOWN_PARAGRAPH, _), body) =>
          val (body1, offset) = html_body(body, end_offset)
          (List(HTML.par(body1)), offset)
        case XML.Elem(Markup(Markup.MARKDOWN_ITEM, _), body) =>
          val (body1, offset) = html_body(body, end_offset)
          (List(HTML.item(body1)), offset)
        case XML.Elem(Markup(Markup.Markdown_Bullet.name, _), text) =>
          (Nil, end_offset - XML.symbol_length(text))
        case XML.Elem(Markup.Markdown_List(kind), body) =>
          val (body1, offset) = html_body(body, end_offset)
          if (kind == Markup.ENUMERATE) (List(HTML.`enum`(body1)), offset)
          else (List(HTML.list(body1)), offset)
        case XML.Elem(markup, body) =>
          val name = markup.name
          val (body1, offset) = html_body(body, end_offset)
          val html =
            markup.properties match {
              case Markup.Kind(kind) if kind == Markup.COMMAND || kind == Markup.KEYWORD =>
                html_class(kind, body1)
              case _ =>
                body1
            }
          Rendering.foreground.get(name) orElse Rendering.text_color.get(name) match {
            case Some(c) => (html_class(c.toString, html), offset)
            case None => (html_class(name, html), offset)
          }
        case XML.Text(text) =>
          val offset = end_offset - Symbol.length(text)
          val body = HTML.text(Symbol.decode(text))
          entity_context.make_def(Text.Range(offset, end_offset), body) match {
            case Some(body1) => (List(body1), offset)
            case None => (body, offset)
          }
      }

    html_body(xml, XML.symbol_length(xml) + 1)._1
  }


  /* PIDE HTML document */

  def html_document(
    snapshot: Document.Snapshot,
    html_context: HTML_Context,
    elements: Elements,
    plain_text: Boolean = false,
    fonts_css: String = HTML.fonts_css()
  ): HTML_Document = {
    require(!snapshot.is_outdated, "document snapshot outdated")

    val name = snapshot.node_name
    if (plain_text) {
      val title = "File " + Symbol.cartouche_decoded(name.path.file_name)
      val body = HTML.text(snapshot.node.source)
      html_context.html_document(title, body, fonts_css)
    }
    else {
      Resources.html_document(snapshot) getOrElse {
        val title =
          if (name.is_theory) "Theory " + quote(name.theory_base_name)
          else "File " + Symbol.cartouche_decoded(name.path.file_name)
        val xml = snapshot.xml_markup(elements = elements.html)
        val body = make_html(Entity_Context.empty, elements, xml)
        html_context.html_document(title, body, fonts_css)
      }
    }
  }



  /** HTML presentation **/

  /* presentation context */

  object Context {
    val none: Context = new Context { def enabled: Boolean = false }
    val standard: Context = new Context { def enabled: Boolean = true }

    def dir(path: Path): Context =
      new Context {
        def enabled: Boolean = true
        override def dir(store: Sessions.Store): Path = path
      }

    def make(s: String): Context =
      if (s == ":") standard else dir(Path.explode(s))
  }

  abstract class Context private {
    def enabled: Boolean
    def enabled(info: Sessions.Info): Boolean = enabled || info.browser_info
    def dir(store: Sessions.Store): Path = store.presentation_dir
    def dir(store: Sessions.Store, info: Sessions.Info): Path =
      dir(store) + Path.explode(info.chapter_session)
  }


  /* maintain chapter index */

  private val sessions_path = Path.basic(".sessions")

  private def read_sessions(dir: Path): List[(String, String)] = {
    val path = dir + sessions_path
    if (path.is_file) {
      import XML.Decode._
      list(pair(string, string))(Symbol.decode_yxml(File.read(path)))
    }
    else Nil
  }

  def update_chapter(
    presentation_dir: Path,
    chapter: String,
    new_sessions: List[(String, String)]
  ): Unit = {
    val dir = Isabelle_System.make_directory(presentation_dir + Path.basic(chapter))

    val sessions0 =
      try { read_sessions(dir) }
      catch { case _: XML.Error => Nil }

    val sessions = (SortedMap.empty[String, String] ++ sessions0 ++ new_sessions).toList
    File.write(dir + sessions_path,
      {
        import XML.Encode._
        YXML.string_of_body(list(pair(string, string))(sessions))
      })

    val title = "Isabelle/" + chapter + " sessions"
    HTML.write_document(dir, "index.html",
      List(HTML.title(title + Isabelle_System.isabelle_heading())),
      HTML.chapter(title) ::
       (if (sessions.isEmpty) Nil
        else
          List(HTML.div("sessions",
            List(HTML.description(
              sessions.map({ case (name, description) =>
                val descr = Symbol.trim_blank_lines(description)
                (List(HTML.link(name + "/index.html", HTML.text(name))),
                  if (descr == "") Nil
                  else HTML.break ::: List(HTML.pre(HTML.text(descr)))) })))))),
      base = Some(presentation_dir))
  }

  def update_root(presentation_dir: Path): Unit = {
    Isabelle_System.make_directory(presentation_dir)
    HTML.init_fonts(presentation_dir)
    Isabelle_System.copy_file(Path.explode("~~/lib/logo/isabelle.gif"),
      presentation_dir + Path.explode("isabelle.gif"))
    val title = "The " + XML.text(Isabelle_System.isabelle_name()) + " Library"
    File.write(presentation_dir + Path.explode("index.html"),
      HTML.header +
"""
<head>
  """ + HTML.head_meta + """
  <title>""" + title + """</title>
</head>

<body text="#000000" bgcolor="#FFFFFF" link="#0000FF" vlink="#000099" alink="#404040">
  <center>
    <table width="100%" border="0" cellspacing="10" cellpadding="0">
      <tr>
        <td width="20%" valign="middle" align="center"><a href="https://isabelle.in.tum.de/"><img align="bottom" src="isabelle.gif" width="100" height="86" alt="[Isabelle]" border="0" /></a></td>

        <td width="80%" valign="middle" align="center">
          <table width="90%" border="0" cellspacing="0" cellpadding="20">
            <tr>
              <td valign="middle" align="center" bgcolor="#AACCCC"><font face="Helvetica,Arial" size="+2">""" + title + """</font></td>
            </tr>
          </table>
        </td>
      </tr>
    </table>
  </center>
  <hr />
""" + File.read(Path.explode("~~/lib/html/library_index_content.template")) +
"""
</body>
""" + HTML.footer)
  }


  /* present session */

  val session_graph_path = Path.explode("session_graph.pdf")
  val readme_path = Path.explode("README.html")

  def html_name(name: Document.Node.Name): String = Path.explode(name.theory_base_name).html.implode
  def files_path(src_path: Path): String = (Path.explode("files") + src_path.squash.html).implode

  private def node_file(name: Document.Node.Name): String =
    if (name.node.endsWith(".thy")) html_name(name) else files_path(name.path)

  private def session_relative(
    deps: Sessions.Deps,
    session0: String,
    session1: String
  ): Option[String] = {
    for {
      info0 <- deps.sessions_structure.get(session0)
      info1 <- deps.sessions_structure.get(session1)
    } yield info0.relative_path(info1)
  }

  def node_relative(
    deps: Sessions.Deps,
    session0: String,
    node_name: Document.Node.Name
  ): Option[String] = {
    val session1 = deps(session0).theory_qualifier(node_name)
    session_relative(deps, session0, session1)
  }

  def session_html(
    session: String,
    deps: Sessions.Deps,
    db_context: Sessions.Database_Context,
    progress: Progress = new Progress,
    verbose: Boolean = false,
    html_context: HTML_Context,
    session_elements: Elements
  ): Unit = {
    val info = deps.sessions_structure(session)
    val options = info.options
    val base = deps(session)

    val session_hierarchy = deps.sessions_structure.build_hierarchy(session)
    val session_dir = Isabelle_System.make_directory(html_context.session_dir(info))

    Bytes.write(session_dir + session_graph_path,
      graphview.Graph_File.make_pdf(options, base.session_graph_display))

    val documents =
      for {
        doc <- info.document_variants
        document <- db_context.database(session)(db =>
          Document_Build.read_document(db, session, doc.name))
      } yield {
        val doc_path = (session_dir + doc.path.pdf).expand
        if (verbose) progress.echo("Presenting document " + session + "/" + doc.name)
        if (options.bool("document_echo")) progress.echo("Document at " + doc_path)
        Bytes.write(doc_path, document.pdf)
        doc
      }

    val view_links = {
      val deps_link =
        HTML.link(session_graph_path, HTML.text("theory dependencies"))

      val readme_links =
        if ((info.dir + readme_path).is_file) {
          Isabelle_System.copy_file(info.dir + readme_path, session_dir + readme_path)
          List(HTML.link(readme_path, HTML.text("README")))
        }
        else Nil

      val document_links =
        documents.map(doc => HTML.link(doc.path.pdf, HTML.text(doc.name)))

      Library.separate(HTML.break ::: HTML.nl,
        (deps_link :: readme_links ::: document_links).
          map(link => HTML.text("View ") ::: List(link))).flatten
    }

    def entity_context(name: Document.Node.Name): Entity_Context =
      Entity_Context.make(session, deps, name, html_context)


    sealed case class Seen_File(
      src_path: Path,
      thy_name: Document.Node.Name,
      thy_session: String
    ) {
      val files_path: Path = html_context.files_path(thy_name, src_path)

      def check(src_path1: Path, thy_name1: Document.Node.Name, thy_session1: String): Boolean = {
        val files_path1 = html_context.files_path(thy_name1, src_path1)
        (src_path == src_path1 || files_path == files_path1) && thy_session == thy_session1
      }
    }
    var seen_files = List.empty[Seen_File]

    def present_theory(name: Document.Node.Name): Option[XML.Body] = {
      progress.expose_interrupt()

      Build_Job.read_theory(db_context, session_hierarchy, name.theory).flatMap { command =>
        if (verbose) progress.echo("Presenting theory " + name)
        val snapshot = Document.State.init.snippet(command)

        val thy_elements =
          session_elements.copy(entity =
            html_context.nodes(name.theory).others.foldLeft(session_elements.entity)(_ + _))

        val files_html =
          for {
            (src_path, xml) <- snapshot.xml_markup_blobs(elements = thy_elements.html)
            if xml.nonEmpty
          }
          yield {
            progress.expose_interrupt()
            if (verbose) progress.echo("Presenting file " + src_path)

            (src_path, html_context.source(
              make_html(Entity_Context.empty, thy_elements, xml)))
          }

        val thy_html =
          html_context.source(
            make_html(entity_context(name), thy_elements,
              snapshot.xml_markup(elements = thy_elements.html)))

        val thy_session = html_context.theory_session(name).name
        val thy_dir = Isabelle_System.make_directory(html_context.theory_dir(name))
        val files =
          for { (src_path, file_html) <- files_html }
            yield {
              seen_files.find(_.check(src_path, name, thy_session)) match {
                case None => seen_files ::= Seen_File(src_path, name, thy_session)
                case Some(seen_file) =>
                  error("Incoherent use of file name " + src_path + " as " + files_path(src_path) +
                    " in theory " + seen_file.thy_name + " vs. " + name)
              }

              val file_path = html_context.files_path(name, src_path)
              val file_title = "File " + Symbol.cartouche_decoded(src_path.implode_short)
              HTML.write_document(file_path.dir, file_path.file_name,
                List(HTML.title(file_title)), List(html_context.head(file_title), file_html),
                base = Some(html_context.root_dir))

              List(HTML.link(files_path(src_path), HTML.text(file_title)))
            }

        val thy_title = "Theory " + name.theory_base_name

        HTML.write_document(thy_dir, html_name(name),
          List(HTML.title(thy_title)), List(html_context.head(thy_title), thy_html),
          base = Some(html_context.root_dir))

        if (thy_session == session) {
          Some(
            List(HTML.link(html_name(name),
              HTML.text(name.theory_base_name) :::
                (if (files.isEmpty) Nil else List(HTML.itemize(files))))))
        }
        else None
      }
    }

    val theories = base.proper_session_theories.flatMap(present_theory)

    val title = "Session " + session
    HTML.write_document(session_dir, "index.html",
      List(HTML.title(title + Isabelle_System.isabelle_heading())),
      html_context.head(title, List(HTML.par(view_links))) ::
        html_context.contents("Theories", theories),
      base = Some(html_context.root_dir))
  }
}