x3d-tidy/src/infer.js

X3D Converter, Beautifier and Minimizer

"use strict";

const
   X3D      = require ("x_ite-node"),
   Traverse = require ("x3d-traverse") (X3D);

module .exports = function inferProfileAndComponents (scene)
{
   const
      browser              = scene .getBrowser (),
      usedComponents       = getUsedComponents (scene),
      profileAndComponents = getProfileAndComponentsFromUsedComponents (browser, usedComponents);

   setProfile    (scene, profileAndComponents .profile);
   setComponents (scene, profileAndComponents .components);
}

function getUsedComponents (scene)
{
   const components = new Map ();

   for (const object of scene .traverse (Traverse .PROTO_DECLARATIONS | Traverse .PROTO_DECLARATION_BODY | Traverse .ROOT_NODES | Traverse .PROTOTYPE_INSTANCES))
   {
      if (!(object instanceof X3D .SFNode))
         continue;

      const
         node          = object .getValue (),
         componentInfo = node .getComponentInfo ();

      if (components .get (componentInfo .name) ?? 0 < componentInfo .level)
         components .set (componentInfo .name, componentInfo .level);
   }

   return components;
}

function getProfileAndComponentsFromUsedComponents (browser, usedComponents)
{
   const profiles = ["Interchange", "Interactive", "Immersive", "Full"] .map (name =>
   {
      return { profile: browser .getProfile (name), components: new Map (usedComponents) };
   });

   profiles .forEach (({ profile, components }) =>
   {
      for (const component of profile .components)
      {
         const level = components .get (component .name);

         if (level === undefined)
            continue;

         if (level > component .level)
            continue;

         components .delete (component .name);
      }
   });

   const { object } = profiles .reduce ((min, object) =>
   {
      const count = new Set ([
         ... [... object .profile .components] .map (component => component .name),
         ... object .components .keys ()
      ]) .size;

      return min .count < count ? min : {
         count,
         object,
      };
   },
   { count: Number .POSITIVE_INFINITY });

   return {
      profile: object .profile,
      components: Array .from (object .components .keys ())
         .sort ()
         .map (name => browser .getComponent (name, object .components .get (name))),
   };
}

function setProfile (scene, profile)
{
   scene .setProfile (profile);
}

function setComponents (scene, components)
{
   const oldComponents = Array .from (scene .getComponents ());

   for (const component of oldComponents)
      scene .removeComponent (component .name);

   for (const component of components)
      scene .addComponent (component);
}