From d3eb05791747cf9389395e49a85bc493352c4ec4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaakko=20Kera=CC=88nen?= <jaakko.keranen@iki.fi>
Date: Fri, 20 Jan 2017 19:34:32 +0200
Subject: [PATCH] libcore|FS: Keeping track of the version of loaded packages

The version is kept in Package for querying later. Both the file name
and the metadata are checked.
---
 .../sdk/libcore/include/de/filesys/package.h  |  7 ++++
 doomsday/sdk/libcore/src/filesys/package.cpp  | 36 +++++++++++++++++--
 .../sdk/libcore/src/filesys/packageloader.cpp | 12 +++++--
 3 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/doomsday/sdk/libcore/include/de/filesys/package.h b/doomsday/sdk/libcore/include/de/filesys/package.h
index c501c834e3..58a44e6da6 100644
--- a/doomsday/sdk/libcore/include/de/filesys/package.h
+++ b/doomsday/sdk/libcore/include/de/filesys/package.h
@@ -121,6 +121,12 @@ class DENG2_PUBLIC Package : public IObject
      */
     String identifier() const;
 
+    /**
+     * Version of the loaded package. The version can be specified either in the
+     * file name (following an underscore) or in the metadata.
+     */
+    Version version() const;
+
     /**
      * Composes a list of assets contained in the package.
      *
@@ -236,6 +242,7 @@ class DENG2_PUBLIC Package : public IObject
     static String const VAR_PACKAGE_TITLE;
     static String const VAR_ID;
     static String const VAR_TITLE;
+    static String const VAR_VERSION;
 
 private:
     DENG2_PRIVATE(d)
diff --git a/doomsday/sdk/libcore/src/filesys/package.cpp b/doomsday/sdk/libcore/src/filesys/package.cpp
index 189893070d..dae8aaf0b6 100644
--- a/doomsday/sdk/libcore/src/filesys/package.cpp
+++ b/doomsday/sdk/libcore/src/filesys/package.cpp
@@ -27,6 +27,8 @@
 #include "de/ScriptedInfo"
 #include "de/TimeValue"
 
+#include <QRegularExpression>
+
 namespace de {
 
 String const Package::VAR_PACKAGE      ("package");
@@ -35,6 +37,7 @@ String const Package::VAR_PACKAGE_ALIAS("package.alias");
 String const Package::VAR_PACKAGE_TITLE("package.title");
 String const Package::VAR_ID           ("ID");
 String const Package::VAR_TITLE        ("title");
+String const Package::VAR_VERSION      ("version");
 
 static String const PACKAGE_ORDER      ("package.__order__");
 static String const PACKAGE_IMPORT_PATH("package.importPath");
@@ -45,6 +48,7 @@ static String const PACKAGE_TAGS       ("package.tags");
 
 static String const VAR_ID  ("ID");
 static String const VAR_PATH("path");
+static String const VAR_TAGS("tags");
 
 Package::Asset::Asset(Record const &rec) : RecordAccessor(rec) {}
 
@@ -66,12 +70,23 @@ DENG2_PIMPL(Package)
 , DENG2_OBSERVES(File, Deletion)
 {
     File const *file;
+    Version version; // version of the loaded package
 
     Impl(Public *i, File const *f)
         : Base(i)
         , file(f)
     {
-        if (file) file->audienceForDeletion() += this;
+        if (file)
+        {
+            file->audienceForDeletion() += this;
+
+            // Check the file name first, then metadata.
+            version = split(versionedIdentifierForFile(*file)).second;
+            if (!version.isValid())
+            {
+                version = Version(metadata(*file).gets(VAR_VERSION, String()));
+            }
+        }
     }
 
     void fileBeingDeleted(File const &)
@@ -153,9 +168,14 @@ String Package::identifier() const
     return identifierForFile(*d->file);
 }
 
+Version Package::version() const
+{
+    return d->version;
+}
+
 Package::Assets Package::assets() const
 {
-    return ScriptedInfo::allBlocksOfType("asset", d->packageInfo());
+    return ScriptedInfo::allBlocksOfType(QStringLiteral("asset"), d->packageInfo());
 }
 
 bool Package::executeFunction(String const &name)
@@ -309,7 +329,7 @@ void Package::validateMetadata(Record const &packageInfo)
                               .arg(packageInfo.gets("path")));
     }
 
-    static String const required[] = { "title", "version", "license", "tags" };
+    static String const required[] = { "title", "version", "license", VAR_TAGS };
     for (auto const &req : required)
     {
         if (!packageInfo.has(req))
@@ -320,6 +340,16 @@ void Package::validateMetadata(Record const &packageInfo)
                                           .arg(req));
         }
     }
+
+    static QRegularExpression const regexReservedTags("\\b(loaded)\\b");
+    auto match = regexReservedTags.match(packageInfo.gets(VAR_TAGS));
+    if (match.hasMatch())
+    {
+        throw ValidationError("Package::validateMetadata",
+                              QString("Package \"%1\" has a tag that is reserved for internal use (%2)")
+                              .arg(packageInfo.gets("path"))
+                              .arg(match.captured(1)));
+    }
 }
 
 Record &Package::initializeMetadata(File &packageFile, String const &id)
diff --git a/doomsday/sdk/libcore/src/filesys/packageloader.cpp b/doomsday/sdk/libcore/src/filesys/packageloader.cpp
index 6e74a5f442..e967ef921c 100644
--- a/doomsday/sdk/libcore/src/filesys/packageloader.cpp
+++ b/doomsday/sdk/libcore/src/filesys/packageloader.cpp
@@ -39,7 +39,7 @@ static String const VAR_PACKAGE_VERSION("package.version");
 
 DENG2_PIMPL(PackageLoader)
 {
-    LoadedPackages loaded;
+    LoadedPackages loaded; ///< Identifiers are unversioned; only one version can be loaded at a time.
     int loadCounter;
 
     Impl(Public *i) : Base(i), loadCounter(0)
@@ -464,7 +464,15 @@ void PackageLoader::unloadAll()
 
 bool PackageLoader::isLoaded(String const &packageId) const
 {
-    return d->loaded.contains(packageId);
+    // Split ID, check version too if specified.
+    auto const id_ver = Package::split(packageId);
+    auto found = d->loaded.constFind(id_ver.first);
+    if (found == d->loaded.constEnd())
+    {
+        return false;
+    }
+    return (!id_ver.second.isValid() /* no valid version provided in argumnet */ ||
+            id_ver.second == found.value()->version());
 }
 
 bool PackageLoader::isLoaded(File const &file) const