local states = {
  -- Initial state, sets up the plant to full health, then drops to normal state.
  "start": {
    { entry = setup_full_health,   -- Also needs registering?!
      initial = true,
      events = { "tick_day": { next_state = "decreasing" } }
    }
  },

  -- Plant in normal state, loosing water, and slowly dying.
  "decreasing":
    { events =
        { "tick_day":
            { { condition = function(self): return self.current_state < 5 end,
                action = decrease_plant,
                next_state = "decreasing"
              },

              { -- Plant already dead, current state does not need managing.
                next_state = "decreasing"
              }
            },
          "watering":
            { { next_state = "restoring" }
            },
          "pick_up":
            { { action = unregister_plant,
                next_state = "picked_up"
              }
            }
        }
    },

  -- Plant got watered, and is recovering to full health.
  "restoring":
    { entry = setup_restore,
      events =
        { "tick_day":
            { { condition = function(self): return self.current_state > 1 end,
                action = restore_plant,
                next_state = "restoring"
              },
              { -- Restored to full health, go back to decreasing
                action = function(self)
                  self.days_left = DAYS_BETWEEN_STATES
                end,
                next_state = "decreasing"
              }
            }
          "watering":
            { { next_state = "restoring" } -- Already restoring, do nothing.
            }
          "pick_up":
            { { action = unregister_plant,
                next_state = "picked_up"
              }
            }
        }
    },
  "picked_up" :
    { events =
        { "drop":
            { { action = register_plant,
                next_state = "decreasing"
              }
            }
        }
    }
}