plugins/net.mograsim.plugin.core/src/net/mograsim/plugin/nature/MachineContext.java

   1 package net.mograsim.plugin.nature;
   2
   3 import java.io.IOException;
   4 import java.util.Objects;
   5 import java.util.Optional;
   6
   7 import org.eclipse.core.resources.IProject;
   8 import org.eclipse.jface.util.PropertyChangeEvent;
   9 import org.eclipse.ui.preferences.ScopedPreferenceStore;
  10
  11 import net.mograsim.machine.Machine;
  12 import net.mograsim.machine.MachineDefinition;
  13 import net.mograsim.machine.MachineRegistry;
  14
  15 public class MachineContext
  16 {
  17         IProject owner;
  18         ScopedPreferenceStore prefs;
  19         Optional<String> machineId;
  20         Optional<MachineDefinition> machineDefinition;
  21         Optional<Machine> activeMachine;
  22
  23         public MachineContext(IProject owner)
  24         {
  25                 this.owner = Objects.requireNonNull(owner);
  26                 prefs = ProjectMachineContext.getProjectPrefs(owner);
  27                 prefs.addPropertyChangeListener(this::preferenceListener);
  28                 machineId = ProjectMachineContext.getMachineIdFrom(prefs);
  29                 updateDefinition();
  30         }
  31
  32         public final IProject getProject()
  33         {
  34                 return owner;
  35         }
  36
  37         public final ScopedPreferenceStore getPreferences()
  38         {
  39                 return prefs;
  40         }
  41
  42         /**
  43          * Returns true if the project configuration is valid in the current environment
  44          */
  45         public final boolean isCurrentyValid()
  46         {
  47                 return machineDefinition.isPresent();
  48         }
  49
  50         /**
  51          * Returns true if the persisted project configuration itself is intact
  52          */
  53         public final boolean isIntact()
  54         {
  55                 return machineId.isPresent();
  56         }
  57
  58         /**
  59          * Returns true if a machine is instantiated and (possibly) running
  60          */
  61         public final boolean isActive()
  62         {
  63                 return activeMachine.isPresent();
  64         }
  65
  66         /**
  67          * Sets the projects machineId. Will likely break things, if the {@link MachineContext} {@link #isActive()}.
  68          */
  69         public final boolean setMachineId(String machineId)
  70         {
  71                 prefs.setValue(ProjectMachineContext.MACHINE_PROPERTY, machineId);
  72                 try
  73                 {
  74                         prefs.save();
  75                 }
  76                 catch (IOException e)
  77                 {
  78                         e.printStackTrace();
  79                         return false;
  80                 }
  81                 return true;
  82         }
  83
  84         /**
  85          * Sets the active machine in the {@link MachineContext}'s project scope.
  86          */
  87         public final void setActiveMachine(Machine machine)
  88         {
  89                 activeMachine = Optional.ofNullable(machine);
  90         }
  91
  92         public final Optional<String> getMachineId()
  93         {
  94                 return machineId;
  95         }
  96
  97         public final Optional<MachineDefinition> getMachineDefinition()
  98         {
  99                 return machineDefinition;
 100         }
 101
 102         public final Optional<Machine> getActiveMachine()
 103         {
 104                 return activeMachine;
 105         }
 106
 107         final void updateDefinition()
 108         {
 109                 machineDefinition = machineId.map(MachineRegistry::getMachine);
 110         }
 111
 112         private void preferenceListener(PropertyChangeEvent changeEvent)
 113         {
 114                 if (changeEvent.getProperty().equals(ProjectMachineContext.MACHINE_PROPERTY))
 115                 {
 116                         machineId = Optional.ofNullable((String) changeEvent.getNewValue());
 117                         updateDefinition();
 118                 }
 119         }
 120 }