Add version switcher script and js

Author: altheaden

docs/generate_versions_json.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+import argparse
+import json
+import os
+import re
+
+
+def version_key(name):
+    """Key function for sorting versions."""
+    match = re.match(r'^(\d+)\.(\d+)\.(\d+)$', name)
+    if match:
+        # Sort by major, minor, patch
+        return tuple(map(int, match.groups()))
+    return ()
+
+
+# Mode: local or production
+parser = argparse.ArgumentParser(
+    description='Generate versions.json for MPAS Analysis documentation.')
+parser.add_argument(
+    '--local',
+    action='store_true',
+    help='Generate versions.json for local build.'
+)
+args = parser.parse_args()
+local = args.local
+base_dir = '_build/html' if local else 'gh-pages'
+shared_dir = os.path.join(base_dir, 'shared')
+
+entries = []
+
+if not os.path.exists(base_dir) or not os.listdir(base_dir):
+    raise FileNotFoundError(
+        f"Base directory '{base_dir}' does not exist or is empty.")
+
+versions = os.listdir(base_dir)
+numeric_versions = []
+non_numeric_versions = []
+
+for version in versions:
+    # Check if it matches version pattern
+    if re.match(r'^\d+\.\d+\.\d+$', version):
+        numeric_versions.append(version)
+    else:
+        non_numeric_versions.append(version)
+
+# Sort numeric versions by major, minor, patch in descending order
+numeric_versions.sort(key=version_key, reverse=True)
+# Sort non-numeric versions alphabetically
+non_numeric_versions.sort()
+
+# Combine the sorted lists
+versions = non_numeric_versions + numeric_versions
+
+if 'main' in versions:
+    versions.insert(0, versions.pop(versions.index('main')))
+
+for name in versions:
+    path = os.path.join(base_dir, name)
+    if os.path.isdir(path) and name not in ('shared', '.git'):
+        entries.append({
+            'version': name,
+            'url': f'../{name}/' if local else f'/mpas_analysis/{name}/'
+        })
+
+os.makedirs(shared_dir, exist_ok=True)
+with open(os.path.join(shared_dir, 'versions.json'), 'w') as f:
+    json.dump(entries, f, indent=2)
+

docs/version-switcher.js

@@ -0,0 +1,48 @@
+(async function () {
+  const container = document.getElementById("version-switcher");
+  if (!container) return;
+
+  const metaVersion = document.querySelector('meta[name="doc-version"]');
+  const currentVersion = metaVersion ? metaVersion.content : "unknown";
+  console.log("Detected current version:", currentVersion);
+
+  async function fetchVersions() {
+    try {
+      const scriptUrl = document.currentScript.src;
+      const basePath = scriptUrl.substring(0, scriptUrl.lastIndexOf('/') + 1);
+      const versionsUrl = basePath + "versions.json";
+
+      const res = await fetch(versionsUrl);
+      if (!res.ok) throw new Error(`Failed to load ${versionsUrl}`);
+      return await res.json();
+    } catch (err) {
+      console.error("Could not load versions.json:", err);
+      return [];
+    }
+  }
+
+  const versions = await fetchVersions();
+  if (!versions.length) return;
+
+  const select = document.createElement("select");
+  select.style.marginLeft = "1em";
+  select.onchange = () => {
+    window.location.href = select.value;
+  };
+
+  versions.forEach(({ version, url }) => {
+    const option = document.createElement("option");
+    option.value = url;
+    option.textContent = version;
+    if (version === currentVersion) {
+      option.selected = true;
+    }
+    select.appendChild(option);
+  });
+
+  const label = document.createElement("label");
+  label.textContent = "Version: ";
+  label.style.color = "white";
+  label.appendChild(select);
+  container.appendChild(label);
+})();