T-566 封面历史归档数据层

app/image_paths.py

@@ -1,4 +1,5 @@
 import os
+import re
 
 from .config import make_slug
 
@@ -22,6 +23,27 @@ def task_image_path(image_root, task, account=None, suffix="old", ext=".jpg"):
     )
 
 
+def list_task_cover_candidates(image_root, task, account=None):
+    """Return generated cover candidates for one task from the image directory."""
+
+    canonical_path = task_image_path(image_root, task, account=account, suffix="new", ext=".jpg")
+    directory = os.path.dirname(canonical_path)
+    prefix = os.path.splitext(os.path.basename(canonical_path))[0]
+    if not os.path.isdir(directory):
+        return []
+    candidates = []
+    for filename in os.listdir(directory):
+        full_path = os.path.join(directory, filename)
+        if not os.path.isfile(full_path):
+            continue
+        stem, ext = os.path.splitext(filename)
+        if ext.lower() != ".jpg":
+            continue
+        if stem == prefix or stem.startswith(prefix + "_"):
+            candidates.append(os.path.abspath(full_path))
+    return sorted(candidates, key=lambda path: _cover_candidate_sort_key(path, prefix))
+
+
 def _account_slug(account, task):
     slug = _get(account, "slug")
     if slug:
@@ -32,6 +54,22 @@ def _account_slug(account, task):
     return "unknown_account"
 
 
+def _cover_candidate_sort_key(path, prefix):
+    filename = os.path.basename(path)
+    stem, _ext = os.path.splitext(filename)
+    if stem == prefix:
+        return (0, 0, 0, filename)
+    marker = prefix + "_"
+    if stem.startswith(marker):
+        suffix = stem[len(marker):]
+        match = re.fullmatch(r"(\d{14})(?:_(\d+))?", suffix)
+        if match:
+            timestamp = int(match.group(1))
+            collision = int(match.group(2) or 1)
+            return (1, -timestamp, -collision, filename)
+    return (2, 0, 0, filename)
+
+
 def _get(obj, name, default=None):
     if obj is None:
         return default
@@ -45,4 +83,4 @@ def _safe_component(value, default):
     if not text:
         text = str(default)
     safe = "".join(ch if ch.isalnum() or ch in "_-" else "_" for ch in text).strip("_")
-    return safe or str(default)
+    return safe or str(default)