// SPDX-License-Identifier: MIT

package openadr

import "strconv"

// ValueKind is the JSON type of a Value.

type ValueKind uint8

// Kinds of value a ValuesMap may hold.

const (

KindNumber ValueKind = iota + 1

KindString

KindBool

KindPoint

)

func (k ValueKind) String() string {

switch k {

case KindNumber:

return "number"

case KindString:

return "string"

case KindBool:

return "bool"

case KindPoint:

return "point"

default:

return "invalid"

}

}

// Point is a pair of numbers, typically a point on a two dimensional grid.

type Point struct {

X, Y float64

}

// Value is one data point of a ValuesMap: a number, a string, a boolean or

// a Point. The zero Value is invalid. Values are comparable with ==.

//

// JSON does not distinguish integers from other numbers, so both are held as

// a float64; integers beyond 2^53 lose precision.

type Value struct {

kind ValueKind

num float64

str string

b bool

pt Point

}

// Number returns a numeric Value.

func Number(n float64) Value { return Value{kind: KindNumber, num: n} }

// String returns a string Value.

func String(s string) Value { return Value{kind: KindString, str: s} }

// Bool returns a boolean Value.

func Bool(b bool) Value { return Value{kind: KindBool, b: b} }

// PointValue returns a Value holding the point (x, y).

func PointValue(x, y float64) Value { return Value{kind: KindPoint, pt: Point{X: x, Y: y}} }

// Kind reports what the Value holds; it is 0 for the zero Value.

func (v Value) Kind() ValueKind { return v.kind }

// Number returns the number held and whether the Value is a number.

func (v Value) Number() (float64, bool) { return v.num, v.kind == KindNumber }

// Text returns the string held and whether the Value is a string.

func (v Value) Text() (string, bool) { return v.str, v.kind == KindString }

// Bool returns the boolean held and whether the Value is a boolean.

func (v Value) Bool() (bool, bool) { return v.b, v.kind == KindBool }

// Point returns the point held and whether the Value is a point.

func (v Value) Point() (Point, bool) { return v.pt, v.kind == KindPoint }

// String formats the Value for diagnostics.

func (v Value) String() string {

switch v.kind {

case KindNumber:

return strconv.FormatFloat(v.num, 'f', -1, 64)

case KindString:

return strconv.Quote(v.str)

case KindBool:

return strconv.FormatBool(v.b)

case KindPoint:

return "(" + strconv.FormatFloat(v.pt.X, 'f', -1, 64) + "," + strconv.FormatFloat(v.pt.Y, 'f', -1, 64) + ")"

default:

return "<invalid>"

}

}