package engine

// MaxAltitude triggers when altitude rises above Limit (in metres).
// Used as the burst condition for ascent stages.
type MaxAltitude struct {
	Limit float64
	On    Action
}

func (c MaxAltitude) Name() string                       { return "max_altitude" }
func (c MaxAltitude) Violated(_ float64, s State) bool   { return s.Altitude >= c.Limit }
func (c MaxAltitude) Action() Action                     { return c.On }

// MinAltitude triggers when altitude falls at or below Limit (in metres).
// With Limit=0 this is the "sea level" terminator.
type MinAltitude struct {
	Limit float64
	On    Action
}

func (c MinAltitude) Name() string                     { return "min_altitude" }
func (c MinAltitude) Violated(_ float64, s State) bool { return s.Altitude <= c.Limit }
func (c MinAltitude) Action() Action                   { return c.On }

// MaxTime triggers when t exceeds Limit (UNIX seconds). Used as a stop
// condition for float profiles.
type MaxTime struct {
	Limit float64
	On    Action
}

func (c MaxTime) Name() string                       { return "max_time" }
func (c MaxTime) Violated(t float64, _ State) bool   { return t > c.Limit }
func (c MaxTime) Action() Action                     { return c.On }

// TerrainContact triggers when altitude has dropped at or below ground level.
// Equivalent to Tawhiri's elevation termination.
type TerrainContact struct {
	Provider TerrainProvider
	On       Action
}

func (c TerrainContact) Name() string { return "terrain_contact" }
func (c TerrainContact) Violated(_ float64, s State) bool {
	return c.Provider.Elevation(s.Lat, s.Lng) > s.Altitude
}
func (c TerrainContact) Action() Action { return c.On }