chore: Add XEP comparison script

The idea is that we keep our DOAP file updated.
Then we always know which version of a XEP we implemented.
By running this script we can then find out if a new version of a XEP
came out.
And we can check whether we need to update our code to adhere to the
latest version or whether we can just version bump.

scripts/check-new-xeps.py

@@ -0,0 +1,136 @@
+#!/usr/bin/env python3
+import os
+import re
+import sys
+import urllib.request
+import xml.etree.ElementTree as ET
+from itertools import zip_longest
+from typing import Dict, List, Optional
+
+
+# Namespaces in DOAP
+NS = {
+    "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
+    "foaf": "http://xmlns.com/foaf/0.1/",
+    "doap": "http://usefulinc.com/ns/doap#",
+    "xmpp": "https://linkmauve.fr/ns/xmpp-doap#",
+    "schema": "https://schema.org/",
+}
+
+
+def compare_versions(v1: str, v2: str) -> int:
+    """
+    Compare two version strings.
+    Returns 1 if v2 > v1, -1 if v1 > v2, 0 if equal.
+    """
+    def parse_v(v: str) -> List[int]:
+        return [int(x) for x in re.split(r"[^0-9]+", v) if x]
+
+    parts1 = parse_v(v1)
+    parts2 = parse_v(v2)
+
+    for p1, p2 in zip_longest(parts1, parts2, fillvalue=0):
+        if p2 > p1:
+            return 1
+        if p1 > p2:
+            return -1
+    return 0
+
+
+def find_doap() -> Optional[str]:
+    """Try to find profanity.doap in current or parent directory."""
+    candidates = ["profanity.doap", "../profanity.doap"]
+    for c in candidates:
+        if os.path.exists(c):
+            return c
+    return None
+
+
+def get_implemented_xeps(doap_path: str) -> Dict[str, str]:
+    """Parse DOAP file and return a map of XEP number to version."""
+    implemented_xeps: Dict[str, str] = {}
+    try:
+        tree = ET.parse(doap_path)
+        root = tree.getroot()
+
+        for implements in root.findall(".//doap:implements", NS):
+            supported_xep = implements.find(".//xmpp:SupportedXep", NS)
+            if supported_xep is not None:
+                xep_res = supported_xep.find(".//xmpp:xep", NS)
+                version_elem = supported_xep.find(".//xmpp:version", NS)
+
+                if xep_res is not None and version_elem is not None:
+                    resource = xep_res.attrib.get(f"{{{NS['rdf']}}}resource", "")
+                    match = re.search(r"xep-(\d+)\.html", resource)
+                    if match:
+                        xep_num = match.group(1)
+                        current_version = version_elem.text.strip() if version_elem.text else ""
+                        implemented_xeps[xep_num] = current_version
+    except (ET.ParseError, PermissionError) as e:
+        print(f"Error reading {doap_path}: {e}")
+        sys.exit(1)
+
+    return implemented_xeps
+
+
+def check_xeps() -> None:
+    """Main logic for checking XEP updates."""
+    doap_path = find_doap()
+    if not doap_path:
+        print("Error: Could not find DOAP file.")
+        sys.exit(1)
+
+    implemented_xeps = get_implemented_xeps(doap_path)
+    if not implemented_xeps:
+        print("No XEPs found in DOAP file.")
+        return
+
+    print(f"XEPs tracked: {len(implemented_xeps)}")
+
+    try:
+        url = "https://xmpp.org/extensions/xeplist.xml"
+        with urllib.request.urlopen(url, timeout=15) as response:
+            xeplist_xml = response.read()
+    except Exception as e:
+        print(f"Error fetching xeplist.xml: {e}")
+        return
+
+    try:
+        xeplist_tree = ET.fromstring(xeplist_xml)
+    except ET.ParseError as e:
+        print(f"Error parsing xeplist.xml: {e}")
+        return
+
+    print(f"\n{'XEP':<10} | {'Name':<35} | {'Ours':<8} | {'Latest':<8}")
+    print("-" * 80)
+
+    updates_found = 0
+    for xep_node in xeplist_tree.findall("xep"):
+        number_node = xep_node.find("number")
+        title_node = xep_node.find("title")
+        last_revision_node = xep_node.find("last-revision")
+
+        if number_node is None or title_node is None or last_revision_node is None:
+            continue
+
+        number = (number_node.text or "0").zfill(4)
+        name = title_node.text or "Unknown"
+        version_node = last_revision_node.find("version")
+
+        if version_node is None or version_node.text is None:
+            continue
+
+        latest_version = version_node.text
+
+        if number in implemented_xeps:
+            old_version = implemented_xeps[number]
+            if compare_versions(old_version, latest_version) > 0:
+                print(f"XEP-{number:<4} | {name[:35]:<35} | {old_version:<8} | {latest_version:<8}")
+                updates_found += 1
+
+    if updates_found == 0:
+        print("All tracked XEPs are up to date.")
+
+
+if __name__ == "__main__":
+    check_xeps()