Created the page-concatinator build module

This produces a single unified version of the entire GDB on one page at /gdb/printable

build/page-concatinator.js

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+
+const Page = require('./page');
+
+function isDate (input) { return input instanceof Date; }
+
+function min (...collection) {
+  if (isDate(collection[0])) return new Date(Math.min(...collection));
+  return Math.min(...collection);
+}
+
+function max (...collection) {
+  if (isDate(collection[0])) return new Date(Math.max(...collection));
+  return Math.max(...collection);
+}
+
+module.exports = exports = function (pages, target, paths, meta) {
+  const sources = {};
+  for (const page of pages) {
+    if (paths.includes(page.input)) sources[page.input] = page;
+  }
+
+  const result = new CombinedPage(target);
+  result.source = '';
+  result.meta = {};
+  result.dateCreated = new Date();
+  result.dateModified = new Date(1990, 12, 1);
+  result.tweets = {};
+  result.images = {};
+  result.meta = meta;
+  result.classes = Array.from(new Set(meta.classes || []));
+  result.flags = result.classes.reduce((res, item) => {
+    var camelCased = item.replace(/-([a-z])/g, (g) => g[1].toUpperCase());
+    res[camelCased] = true;
+    return res;
+  }, {});
+
+  for (const path of paths) {
+    const p = sources[path];
+    result.source += p.source;
+
+    result.dateCreated = min(result.dateCreated, p.dateCreated);
+    result.dateModified = max(result.dateModified, p.dateModified);
+    Object.assign(result.images, p.images);
+    Object.assign(result.tweets, p.tweets);
+  }
+
+  result.meta.date = result.dateCreated;
+
+  return result;
+};
+
+
+
+class CombinedPage extends Page {
+
+  async load () {
+    // do nothing
+  }
+
+}