Package dependencies.

simgear/package/Catalog.cxx

@@ -221,6 +221,11 @@ std::string Catalog::description() const
 {
     return getLocalisedString(m_props, "description");
 }
+    
+SGPropertyNode* Catalog::properties() const
+{
+    return m_props.ptr();
+}
 
 void Catalog::parseTimestamp()
 {

simgear/package/Catalog.hxx

@@ -65,6 +65,11 @@ public:
     Package* getPackageById(const std::string& aId) const;
     
     unsigned int ageInSeconds() const;
+    
+    /**
+     * access the raw property data in the catalog
+     */
+    SGPropertyNode* properties() const;
 private:
     Catalog(Root* aRoot);
     

simgear/package/Package.cxx

@@ -2,9 +2,12 @@
 
 #include <simgear/package/Package.hxx>
 
+#include <cassert>
 #include <boost/foreach.hpp>
 
 #include <simgear/debug/logstream.hxx> 
+#include <simgear/structure/exception.hxx>
+
 #include <simgear/package/Catalog.hxx>
 #include <simgear/package/Install.hxx>
 #include <simgear/package/Root.hxx>
@@ -93,6 +96,20 @@ unsigned int Package::revision() const
 {
     return m_props->getIntValue("revision");
 }
+    
+SGPropertyNode* Package::properties() const
+{
+    return m_props.ptr();
+}
+
+string_list Package::thumbnailUrls() const
+{
+    string_list r;
+    BOOST_FOREACH(SGPropertyNode* dl, m_props->getChildren("thumbnail")) {
+        r.push_back(dl->getStringValue());
+    }
+    return r;
+}
 
 string_list Package::downloadUrls() const
 {
@@ -121,6 +138,40 @@ std::string Package::getLocalisedString(const SGPropertyNode* aRoot, const char*
     return aRoot->getStringValue(aName);
 }
 
+PackageList Package::dependencies() const
+{
+    PackageList result;
+    
+    BOOST_FOREACH(SGPropertyNode* dep, m_props->getChildren("depends")) {
+        std::string depName = dep->getStringValue("package");
+        unsigned int rev = dep->getIntValue("revision", 0);
+        
+    // prefer local hangar package if possible, in case someone does something
+    // silly with naming. Of course flightgear's aircraft search doesn't know
+    // about hanagrs, so names still need to be unique.
+        Package* depPkg = m_catalog->getPackageById(depName);
+        if (!depPkg) {   
+            Root* rt = m_catalog->root();
+            depPkg = rt->getPackageById(depName);
+            if (!depPkg) {
+                throw sg_exception("Couldn't satisfy dependency of " + id() + " : " + depName);
+            }
+        }
+        
+        if (depPkg->revision() < rev) {
+            throw sg_range_exception("Couldn't find suitable revision of " + depName);
+        }
+    
+    // forbid recursive dependency graphs, we don't need that level
+    // of complexity for aircraft resources
+        assert(depPkg->dependencies() == PackageList());
+        
+        result.push_back(depPkg);
+    }
+    
+    return result;
+}
+
 } // of namespace pkg
 
 } // of namespace simgear

simgear/package/Package.hxx

@@ -18,7 +18,10 @@ namespace pkg
 // forward decls
 class Install;
 class Catalog;
+class Package;
 
+typedef std::vector<Package*> PackageList;
+    
 class Package
 {
 public:
@@ -31,6 +34,14 @@ public:
     
     std::string id() const;
     
+    /**
+     * access the raw property data in the package
+     */
+    SGPropertyNode* properties() const;
+    
+    /**
+     * hex-encoded MD5 sum of the download files
+     */
     std::string md5() const;
     
     std::string getLocalisedProp(const std::string& aName) const;
@@ -42,7 +53,19 @@ public:
     
     bool matches(const SGPropertyNode* aFilter) const;
     
+    /**
+     * download URLs for the package
+     */
     string_list downloadUrls() const;
+    
+    string_list thumbnailUrls() const;
+    
+    /**
+     * Packages we depend upon.
+     * If the dependency list cannot be satisifed for some reason,
+     * this will raise an sg_exception.
+     */
+    PackageList dependencies() const;
 private:
     friend class Catalog;
     
@@ -57,7 +80,7 @@ private:
     Catalog* m_catalog;
 };
 
-typedef std::vector<Package*> PackageList;
+
 
 
 } // of namespace pkg

simgear/package/Root.cxx

@@ -162,7 +162,18 @@ std::string Root::getLocale() const
 
 void Root::scheduleToUpdate(Install* aInstall)
 {
-    bool wasEmpty = m_updateDeque.empty();
+    if (!aInstall) {
+        sg_exception("missing argument to scheduleToUpdate");
+    }
+    
+    PackageList deps = aInstall->package()->dependencies();
+    BOOST_FOREACH(Package* dep, deps) {
+        // will internally schedule for update if required
+        // hence be careful, this method is re-entered in here!
+        dep->install();
+    }
+
+    bool wasEmpty = m_updateDeque.empty();    
     m_updateDeque.push_back(aInstall);
     if (wasEmpty) {
         aInstall->startUpdate();