From 6fd3ba95ba442b866e12f803c4914771319c51cb Mon Sep 17 00:00:00 2001
From: lilydjwg <lilydjwg@gmail.com>
Date: Fri, 25 Jun 2021 15:22:40 +0800
Subject: [PATCH] apt: handle multiple verions correctly

closes #191
---
 nvchecker_source/apt.py | 74 +++++++++++++++++++++++++++++++++++++----
 tests/test_apt.py       | 11 ++++++
 2 files changed, 79 insertions(+), 6 deletions(-)

diff --git a/nvchecker_source/apt.py b/nvchecker_source/apt.py
index e04ef59..dddb634 100644
--- a/nvchecker_source/apt.py
+++ b/nvchecker_source/apt.py
@@ -3,9 +3,12 @@
 
 from __future__ import annotations
 
+import re
 import asyncio
-from io import StringIO
 from typing import Dict, Tuple
+import itertools
+import functools
+from collections import defaultdict
 
 from nvchecker.api import (
   session, GetVersionError,
@@ -17,6 +20,60 @@ APT_PACKAGES_PATH = "%s/binary-%s/Packages%s"
 APT_PACKAGES_URL = "%s/dists/%s/%s"
 APT_PACKAGES_SUFFIX_PREFER = (".xz", ".gz", "")
 
+DpkgVersion = Tuple[int, str, str]
+
+def parse_version(s: str) -> DpkgVersion:
+  try:
+    epoch_str, rest = s.split(':', 1)
+  except ValueError:
+    epoch = 0
+    rest = s
+  else:
+    epoch = int(epoch_str)
+
+  try:
+    ver, rev = rest.split('-', 1)
+  except ValueError:
+    ver = rest
+    rev = ''
+
+  return epoch, ver, rev
+
+def _compare_part(a: str, b: str) -> int:
+  sa = re.split(r'(\d+)', a)
+  sb = re.split(r'(\d+)', b)
+  for idx, (pa, pb) in enumerate(itertools.zip_longest(sa, sb)):
+    if pa is None:
+      return -1
+    elif pb is None:
+      return 1
+
+    if idx % 2 == 1:
+      ret = int(pa) - int(pb)
+      if ret != 0:
+        return ret
+    else:
+      if pa < pb:
+        return -1
+      elif pa > pb:
+        return 1
+
+  return 0
+
+def compare_version_parsed(a: DpkgVersion, b: DpkgVersion) -> int:
+  ret = a[0] - b[0]
+  if ret != 0:
+    return ret
+  ret = _compare_part(a[1], b[1])
+  if ret != 0:
+    return ret
+  return _compare_part(a[2], b[2])
+
+def compare_version(a: str, b: str) -> int:
+  va = parse_version(a)
+  vb = parse_version(b)
+  return compare_version_parsed(va, vb)
+
 def _decompress_data(url: str, data: bytes) -> str:
   if url.endswith(".xz"):
     import lzma
@@ -39,8 +96,8 @@ async def parse_packages(key: Tuple[AsyncCache, str]) -> Tuple[Dict[str, str], D
   cache, url = key
   apt_packages = await cache.get(url, get_url) # type: ignore
 
-  pkg_map = {}
-  srcpkg_map = {}
+  pkg_map = defaultdict(list)
+  srcpkg_map = defaultdict(list)
 
   pkg = None
   srcpkg = None
@@ -52,12 +109,17 @@ async def parse_packages(key: Tuple[AsyncCache, str]) -> Tuple[Dict[str, str], D
     elif line.startswith("Version: "):
       version = line[9:]
       if pkg is not None:
-        pkg_map[pkg] = version
+        pkg_map[pkg].append(version)
       if srcpkg is not None:
-        srcpkg_map[srcpkg] = version
+        srcpkg_map[srcpkg].append(version)
       pkg = srcpkg = None
 
-  return pkg_map, srcpkg_map
+  pkg_map_max = {pkg: max(vs, key=functools.cmp_to_key(compare_version))
+                 for pkg, vs in pkg_map.items()}
+  srcpkg_map_max = {pkg: max(vs, key=functools.cmp_to_key(compare_version))
+                 for pkg, vs in srcpkg_map.items()}
+
+  return pkg_map_max, srcpkg_map_max
 
 async def get_version(
   name: str, conf: Entry, *,
diff --git a/tests/test_apt.py b/tests/test_apt.py
index adcc07b..aef8a2e 100644
--- a/tests/test_apt.py
+++ b/tests/test_apt.py
@@ -39,3 +39,14 @@ async def test_apt_deepin(get_version):
         "mirror": "https://community-packages.deepin.com/deepin",
         "suite": "apricot",
     }) == "0.1.6-1"
+
+@flaky(max_runs=10)
+async def test_apt_multiversions(get_version):
+    assert await get_version("ms-teams", {
+        "source": "apt",
+        "mirror": "https://packages.microsoft.com/repos/ms-teams",
+        "pkg": "teams",
+        "suite": "stable",
+        "repo": "main",
+        "arch": "amd64",
+    }) == "1.4.00.13653"