inertia

type DataSink interface {

	// Pass in static system parameters to the visualization.
	// Should be called exactly once, before any Updates are provided.
	Init(SystemMetadata) error

	// Pass in a new SystemState to be added to the visualization.
	Update(Snapshot)
}

type DataSource interface {

	// Types implementing DataSource should have a Metadata method that
	// returns SystemMetadata information.
	Metadata() SystemMetadata

	// Query the DataSource, returning the oldest unseen data if it's
	// available, or an error otherwise (e.g. if no new data is available).
	// This allows for making repeated queries until there's
	// nothing new to report, at which point the user can wait some amount of
	// time before trying again.
	Query() (Snapshot, error)
}

type Region struct {
	Name string `json:"name"`
}

type Snapshot struct {
	Time        time.Time
	Requirement float64
	Total       UnitAggregation
	Categories  map[string]*UnitAggregation
	Regions     map[string]*UnitAggregation
}

type SystemMetadata struct {
	Regions    map[string]*Region       `json:"regions"`
	Categories map[string]*UnitCategory `json:"categories"`
	Units      map[string]UnitMetadata
}

type SystemState struct {
	Time        time.Time
	Requirement float64
	Units       []UnitState
	System      *SystemMetadata
}

type UnitAggregation struct {
	Units        int     `json:"units"`
	TotalRating  float64 `json:"total_rating"`
	TotalInertia float64 `json:"total_inertia"`
}

type UnitCategory struct {
	Name  string `json:"name"`
	Color string `json:"color"`
	Order int    `json:"order"`
}

type UnitMetadata struct {
	Name     string
	Category *UnitCategory
	Region   *Region
	Rating   float64 // in MVA
	H        float64 // in s
}

type UnitState struct {
	UnitMetadata
	Committed bool
}