Support running scenarios (#51)

Closes #42.

src/run.cpp

@@ -4,6 +4,8 @@
 
 #include <boost/filesystem.hpp>
 #include <cse/cse_config_parser.hpp>
+#include <cse/manipulator/scenario_manager.hpp>
+#include <cse/model.hpp>
 #include <cse/observer/file_observer.hpp>
 #include <cse/observer/observer.hpp>
 #include <cse/orchestration.hpp>
@@ -36,7 +38,15 @@ void run_subcommand::setup_options(
             "'none' disables file output altogether.")
         ("output-dir",
             boost::program_options::value<std::string>()->default_value("."),
-            "The path to a directory for storing simulation results.");
+            "The path to a directory for storing simulation results.")
+        ("scenario",
+            boost::program_options::value<std::string>(),
+            "The path to a scenario file to run.  "
+            "By default, no scenario is run.")
+        ("scenario-start",
+            boost::program_options::value<double>()->default_value(0.0),
+            "The logical time at which the scenario will start.  "
+            "Only used if --scenario is specified.");
     positionalOptions.add_options()
         ("system_structure_path",
             boost::program_options::value<std::string>()->required(),
@@ -94,6 +104,17 @@ std::unique_ptr<cse::observer> make_file_observer(
 }
 
 
+void load_scenario(
+    cse::execution& execution,
+    const boost::filesystem::path& scenarioPath,
+    cse::time_point startTime)
+{
+    auto s = std::make_shared<cse::scenario_manager>();
+    execution.add_manipulator(s);
+    s->load_scenario(scenarioPath, startTime);
+}
+
+
 class progress_monitor : public cse::observer
 {
 public:
@@ -155,6 +176,13 @@ int run_subcommand::run(const boost::program_options::variables_map& args) const
         systemStructurePath);
     if (outputObserver) execution.add_observer(std::move(outputObserver));
 
+    if (args.count("scenario")) {
+        load_scenario(
+            execution,
+            args["scenario"].as<std::string>(),
+            cse::to_time_point(args["scenario-start"].as<double>()));
+    }
+
     execution.add_observer(
         std::make_shared<progress_monitor>(
             runOptions.begin_time,