1 files changed, 30 insertions, 4 deletions
diff --git a/pkgs/games/itch/fetch-itch/default.nix b/pkgs/games/itch/fetch-itch/default.nix
index ed1ac7f6..3700f5c6 100644
--- a/pkgs/games/itch/fetch-itch/default.nix
+++ b/pkgs/games/itch/fetch-itch/default.nix
@@ -3,7 +3,7 @@
 , apiKey
 }:
 
-{ name, gameId, uploadId, sha256 }:
+{ name, gameId, uploadId, sha256, version ? null }:
 
 let
   cafile = "${cacert}/etc/ssl/certs/ca-bundle.crt";
@@ -21,15 +21,41 @@ let
     NAME = os.getenv('name')
     GAME_ID = int(os.getenv('gameId'))
     UPLOAD_ID = int(os.getenv('uploadId'))
+    VERSION = os.getenv('version', None)
 
     def request(path):
       with urlopen(urljoin(API_BASE, path)) as u:
         return json.loads(u.read())
 
+    def get_versions(key):
+      url = 'upload/{}/builds'.format(UPLOAD_ID)
+      return request(url + '?download_key_id=' + str(key))['builds']
+
+    def print_download_url(key):
+      if VERSION is not None:
+        versions = get_versions(key)
+        wanted = [ver for ver in versions if ver['user_version'] == VERSION]
+        if len(wanted) == 1:
+          url = 'upload/{}/download/builds/{}?download_key_id={}'.format(
+            UPLOAD_ID, wanted[0]['id'], key
+          )
+          sys.stdout.write(request(url)['archive']['url'] + '\n')
+          return
+        else:
+          msg = 'Unknown version {}, recent versions are:\n'.format(VERSION)
+          sys.stderr.write(msg)
+          for ver in versions[:20]:
+            sys.stderr.write('Update date: {}, version: {}\n'.format(
+              ver['updated_at'], ver['user_version']
+            ))
+          raise SystemExit(1)
+
+      url = 'download-key/{}/download/{}'.format(key, UPLOAD_ID)
+      sys.stdout.write(request(url)['url'] + '\n')
+
     for key in request('my-owned-keys')['owned_keys']:
       if key['game']['id'] == GAME_ID:
-        url = 'download-key/{}/download/{}'.format(key['id'], UPLOAD_ID)
-        sys.stdout.write(request(url)['url'] + '\n')
+        print_download_url(key['id'])
         raise SystemExit(0)
 
     sys.stderr.write('Unable to find download for game {}!'.format(NAME))
@@ -37,7 +63,7 @@ let
   '';
 
 in stdenv.mkDerivation {
-  inherit name apiKey gameId uploadId;
+  inherit name apiKey gameId uploadId version;
   outputHashAlgo = "sha256";
   outputHash = sha256;