wx

type BasicMETAR struct {
	ICAO        string  `json:"icaoId"`
	ReportTime  string  `json:"reportTime"`
	Temperature float32 `json:"temp"`
	Altimeter   float32 `json:"altim"`
	WindDir     any     `json:"wdir"` // nil or string "VRB" for variable, else number for heading
	WindSpeed   int     `json:"wspd"`
	WindGust    *int    `json:"wgst"`
	Raw         string  `json:"rawOb"`
}

type BasicMETARSOA struct {
	// These are all delta coded
	ReportTime  [][]byte
	Temperature []int16 // fixed point, one decimal digit
	Altimeter   []int16 // fixed point, one decimal digit
	WindDir     []int16
	WindSpeed   []int16
	WindGust    []int16

	// This is not; it's not worth delta encoding the raw METAR reports
	// since there's generally not much character alignment between
	// successive reports.
	Raw []string
}

type MBLevelSOA struct {
	MB float32
	// All of the following are delta encoded
	Heading     []uint8 // degrees/2
	Speed       []uint8 // knots
	Temperature []int8  // Temperature in Celsius
	Height      []uint8 // geopotential height + WindHeightOffset in 100s of feet
}

type METAR struct {
	ICAO        string  `json:"icaoId"`
	ReportTime  string  `json:"reportTime"`
	Temperature float32 `json:"temp"` // in Celcius
	Dewpoint    float32 `json:"dewp"` // in Celcius
	Wind        struct {
		Variable  bool
		Direction float32 // Only set/valid if Variable is false.
		Speed     float32 `json:"wspd"` // Wind speed in knots
		Gust      float32 `json:"wgst"` // Wind gusts in knots
	}
	Altimeter float32 `json:"altim"` // in hPa
	RawText   string  `json:"rawOb"` // Raw text of observation

	Latitude  float32 `json:"lat"`
	Longitude float32 `json:"lon"`

	// The JSON comes back sort of wonky; we decode into this but then
	// clean it up into the Wind member above.
	WindDirRaw any `json:"wdir"` // Wind direction in degrees or "VRB" for variable winds

}

type Sample struct {
	MB          float32
	UComponent  float32 // eastward
	VComponent  float32 // northward
	Temperature float32 // Kelvin, evidently
	Height      float32 // geopotential height
}

type SampleSet map[[2]float32][]Sample

type SampleSetSOA struct {
	Lat, Long []float32
	Levels    []MBLevelSOA
}

type WeatherModel struct {
	METAR              map[string]*METAR
	NmPerLongitude     float32
	MagneticVariation  float32
	WindRoot           *WindTreeNode
	StartTime          time.Time
	CurrentTime        time.Time
	GustStartTime      time.Time
	GustActiveDuration time.Duration
	GustCalmDuration   time.Duration
}

type WeatherSample struct {
	Altimeter   float32
	Temperature float32
	Dewpoint    float32
	Wind        WindSample
}

type WindLayer struct {
	Altitude        float32
	Direction       float32    // 0 -> variable
	DirectionVector [2]float32 // normalized vector
	Speed           float32
	Gust            float32
}

type WindSample struct {
	// Vector is the wind vector at the sample time, incorporating
	// gusting, if relevant. Note that it corresponds to the wind's
	// effect on an aircraft (e.g., if the wind heading is 090, the
	// vector will be pointed in the -x direction.)
	Vector    [2]float32
	Direction float32
	Speed     float32 // current speed in knots, including gusting.
	Gust      float32
}

type WindTreeNode struct {
	Children  [2]*WindTreeNode
	Location  math.Point2LL
	SplitAxis int
	Layers    []WindLayer
}