fix #3057: re-upload + detail-view now restore broken mirror links

Three intertwined bugs prevented re-uploading the 5 listed maps from fixing
their "WILL NOT BE DOWNLOADABLE" state:

1. ProbeAndAssign wrote LinkCount = ok ? 1 : 0 based on the springfiles
   probe alone, so a local copy on disk could not lift LinkCount above 0
   when springfiles 404'd (the actual case for Sever_1.sd7 etc, which
   springfiles serves only in lowercase). LinkCount now reflects the total
   mirror count; cache state moves to "cf.Links contains springfilesUrl".

2. UploadResource's .Where(ArchiveName == file.FileName) was case-sensitive,
   so if unitsync's archive cache reported a different casing than the
   browser-supplied filename the result was silently dropped and nothing
   was written. Made case-insensitive.

3. UploadResource copied to res.ResourceInfo.ArchiveName but built the URL
   from file.FileName, so on case-sensitive FS the URL pointed nowhere.
   Copy destination now prefers the DB row's canonical FileName so it
   matches what BuildLinks/File.Exists subsequently probes.

Adds ResourceLinkProvider.RefreshLinks(cf): live local check + cached/
deduped springfiles probe, persists if state changed. Called from
UploadResource (with LastLinkCheck cleared to force a fresh probe — the
user re-uploaded specifically to fix a broken map) and from
GetMapDetailData on every detail view (cheap because of the 24 h cache).

Author: Licho1

Zero-K.info/AppCode/ResourceLinkProvider.cs

@@ -80,18 +80,41 @@ public static List<string> BuildLinks(ResourceContentFile content)
             return links;
         }
 
+        // Recomputes cf.Links/LinkCount from live local-file check + cached/probed springfiles state.
+        // Returns true if the entity changed; caller must SaveChanges() in that case.
+        // Local check is always live (cheap stat); springfiles obeys the 24 h cache and Lazy<bool> dedup.
+        public static bool RefreshLinks(ResourceContentFile cf)
+        {
+            if (cf?.FileName == null || cf.FileName.EndsWith(".sdp") || cf.Resource.MissionID != null) return false;
+
+            var prevLinks = cf.Links;
+            var prevCount = cf.LinkCount;
+            var prevLastCheck = cf.Resource.LastLinkCheck;
+
+            var links = BuildLinks(cf);
+            cf.Links = string.Join("\n", links);
+            cf.LinkCount = links.Count;
+
+            return cf.Links != prevLinks || cf.LinkCount != prevCount || cf.Resource.LastLinkCheck != prevLastCheck;
+        }
+
         // 24 h cache + dedup: at most one HEAD per Md5 in flight regardless of caller count.
-        // LinkCount in DB encodes the cached probe result (1 = springfiles had it, 0 = it didn't).
-        static bool IsSpringfilesAvailable(ResourceContentFile content, string url)
+        // Cache state is the presence of springfilesUrl in cf.Links (set by the last probe);
+        // LinkCount is the total mirror count (local + springfiles), not a springfiles-only flag.
+        // Updates cf.Resource.LastLinkCheck on the caller's entity after a probe so the caller's
+        // db context ends up with the same LastLinkCheck the probe wrote in its own context.
+        static bool IsSpringfilesAvailable(ResourceContentFile content, string springfilesUrl)
         {
             if (content.Resource.LastLinkCheck.HasValue
                 && DateTime.UtcNow.Subtract(content.Resource.LastLinkCheck.Value).TotalHours < SpringfilesRecheckHours)
-                return content.LinkCount > 0;
+                return !string.IsNullOrEmpty(content.Links) && content.Links.Split('\n').Contains(springfilesUrl);
 
             var md5 = content.Md5;
-            return InflightProbes.GetOrAdd(md5, key => new Lazy<bool>(
+            var result = InflightProbes.GetOrAdd(md5, key => new Lazy<bool>(
                 () => RunProbe(key),
                 LazyThreadSafetyMode.ExecutionAndPublication)).Value;
+            content.Resource.LastLinkCheck = DateTime.UtcNow;
+            return result;
         }
 
         // The cache re-check inside the using block covers the gap between Lazy completion
@@ -107,7 +130,11 @@ static bool RunProbe(string md5)
                     if (cf == null) return false;
                     if (cf.Resource.LastLinkCheck.HasValue
                         && DateTime.UtcNow.Subtract(cf.Resource.LastLinkCheck.Value).TotalHours < SpringfilesRecheckHours)
-                        return cf.LinkCount > 0;
+                    {
+                        var subfolder = cf.Resource.TypeID == ResourceType.Map ? "maps" : "games";
+                        var springfilesUrl = $"{GlobalConst.SpringfilesBaseUrl}files/{subfolder}/{cf.FileName}";
+                        return !string.IsNullOrEmpty(cf.Links) && cf.Links.Split('\n').Contains(springfilesUrl);
+                    }
 
                     var ok = ProbeAndAssign(cf);
                     db.SaveChanges();
@@ -144,16 +171,16 @@ static bool ProbeAndAssign(ResourceContentFile cf)
             var localUrl = $"{GlobalConst.BaseSiteUrl}/content/{subfolder}/{cf.FileName}";
             var springfilesUrl = $"{GlobalConst.SpringfilesBaseUrl}files/{subfolder}/{cf.FileName}";
 
-            var ok = HeadCheck(springfilesUrl, cf.Length);
+            var hasSpringfiles = HeadCheck(springfilesUrl, cf.Length);
 
             var links = new List<string>();
             if (File.Exists(Global.MapPath($"~/content/{subfolder}/{cf.FileName}"))) links.Add(localUrl);
-            if (ok) links.Add(springfilesUrl);
+            if (hasSpringfiles) links.Add(springfilesUrl);
 
             cf.Links = string.Join("\n", links);
-            cf.LinkCount = ok ? 1 : 0;
+            cf.LinkCount = links.Count;
             cf.Resource.LastLinkCheck = DateTime.UtcNow;
-            return ok;
+            return hasSpringfiles;
         }
 
         static bool HeadCheck(string url, int length)

Zero-K.info/Controllers/MapsController.cs

@@ -368,6 +368,14 @@ static ZkDataContext FilterMaps(string search,
         }
 
         MapDetailData GetMapDetailData(Resource res, ZkDataContext db) {
+            // opportunistically reconcile mirror state on each view. Local file check is a cheap stat;
+            // springfiles probe is gated by the 24 h cache + dedup so this only HEADs once a day at most.
+            // Fixes the case where a file is on disk in content/maps but LinkCount is stale 0 — see #3057.
+            var anyChanged = false;
+            foreach (var cf in res.ResourceContentFiles)
+                if (ResourceLinkProvider.RefreshLinks(cf)) anyChanged = true;
+            if (anyChanged) db.SaveChanges();
+
             var data = new MapDetailData
             {
                 Resource = res,
@@ -433,33 +441,42 @@ public ActionResult UploadResource(HttpPostedFileBase file, bool specialMap)
             try
             {
                 file.SaveAs(tmp);
-                var results = Global.AutoRegistrator.UnitSyncer.Scan()?.Where(x=>x.ResourceInfo?.ArchiveName == file.FileName)?.ToList();
+                // case-insensitive match: unitsync's archiveCache may report a different casing
+                // than the user uploaded; without OrdinalIgnoreCase the filter silently dropped
+                // the result and nothing got updated — see issue #3057
+                var results = Global.AutoRegistrator.UnitSyncer.Scan()
+                    ?.Where(x => string.Equals(x.ResourceInfo?.ArchiveName, file.FileName, StringComparison.OrdinalIgnoreCase))
+                    ?.ToList();
                 var model = new List<RegistrationResult>();
                 foreach (var res in results)
                 {
                     if (res.Status != UnitSyncer.ResourceFileStatus.RegistrationError)
                     {
-                        // copy to content subfolder
                         var subfolder = (res.ResourceInfo is Map) ? "maps" : "games";
                         var contentFolder = Path.Combine(Server.MapPath("~/content"), subfolder);
                         if (!Directory.Exists(contentFolder)) Directory.CreateDirectory(contentFolder);
 
-                        var destFile = Path.Combine(contentFolder, res.ResourceInfo.ArchiveName);
-                        if (!System.IO.File.Exists(destFile)) System.IO.File.Copy(tmp, destFile);
-
-                        
-                        // register as mirror
+                        // refresh mirrors (local + springfiles)
                         using (var db = new ZkDataContext())
                         {
                             var resource = db.Resources.FirstOrDefault(x => x.InternalName == res.ResourceInfo.Name);
                             // case-insensitive FileName match: DB row may have different casing than the
                             // freshly-uploaded file (springfiles vs original-upload casing) — see issue #3052
                             var contentFile = resource?.ResourceContentFiles.FirstOrDefault(
                                 x => string.Equals(x.FileName, file.FileName, StringComparison.OrdinalIgnoreCase));
+
+                            // copy to content/. Prefer the DB row's canonical FileName so File.Exists
+                            // (case-sensitive on Linux) lines up with what BuildLinks probes — see #3057
+                            var destName = contentFile?.FileName ?? file.FileName;
+                            var destFile = Path.Combine(contentFolder, destName);
+                            if (!System.IO.File.Exists(destFile)) System.IO.File.Copy(tmp, destFile);
+
                             if (contentFile != null)
                             {
-                                contentFile.Links = $"{GlobalConst.BaseSiteUrl}/content/{subfolder}/{file.FileName}";
-                                contentFile.LinkCount = 1;
+                                // force a fresh springfiles probe: the user explicitly re-uploaded to
+                                // fix a broken map, so honor that by bypassing the 24 h cache
+                                contentFile.Resource.LastLinkCheck = null;
+                                ResourceLinkProvider.RefreshLinks(contentFile);
                             }
 
                             // tag as special if required
@@ -470,9 +487,9 @@ public ActionResult UploadResource(HttpPostedFileBase file, bool specialMap)
 
                             db.SaveChanges();
                         }
-                        
+
                     }
-                    
+
                     // note this is needed because of some obscure binding issue in asp.net
                     model.Add(new RegistrationResult()
                     {
@@ -482,7 +499,7 @@ public ActionResult UploadResource(HttpPostedFileBase file, bool specialMap)
                         Author = res.ResourceInfo?.Author,
                         Url = Url.Action("Detail", new {id = new ZkDataContext().Resources.FirstOrDefault(x => x.InternalName == res.ResourceInfo.Name)?.ResourceID})
                     });
-                    
+
                 }
                 return View("UploadResourceResult", model);
             }