cif

type Block struct {
	// The name of this block.
	Name string

	// Items maps data tags to values. Data tags that are part of a "loop_"
	// declaration are not included here.
	Items map[string]Value

	// Loops maps data tags to tables defined by a "loop_" declaration. Namely,
	// each data tag in a "loop_" maps to precisely the same loop object.
	// For example, if a "loop_" introduces the data tag "_cats" with values
	// "Cauchy" and "Plato", then the following code accesses that list of
	// cats:
	//
	//	loop := someBlock.Loops["cats"]
	//	cats := loop.Get("cats").Strings()
	//
	// Notice that the key "cats" is used twice. The first time it's used to
	// get the loop object, while the second time its used is to get the
	// actual column of data.
	Loops map[string]*Loop
}

type CIF struct {
	// Version, when present in the source file, contains the version of the
	// specification that the file was generated for. e.g., "CIF_1.1".
	Version string

	// Blocks maps data block names to corresponding data blocks.
	// Note that all data block names are stored in lowercase.
	Blocks map[string]*DataBlock
}

type DataBlock struct {
	// The name and data items are stored in a block.
	Block

	// Frames maps save frame names to corresponding save frames.
	// Note that all save frame names are stored in lowercase.
	Frames map[string]*SaveFrame
}

type Loop struct {
	// Columns maps data tag names to their position in the table (starting
	// at 0).
	Columns map[string]int

	// Values corresponds to the columns of data in the table. Namely, each
	// ValueLoop is a single column of data.
	Values []ValueLoop
}

type SaveFrame struct {
	// The name and data items are stored in a block.
	Block
}

type Value interface {
	// String returns this value as a string. If its underlying type is
	// numeric, then 0 is returned.
	String() string

	// Int returns this value as an integer. If its underlying type is
	// a float, then an int conversion is performed (which may fail).
	// If its underlying type is a string, then the empty string is returned.
	Int() int

	// Float returns this value as a float64. If its underlying type is
	// an integer, then it is converted to a float.
	// If its underlying type is a string, then the empty string is returned.
	Float() float64

	// Raw provides the underlying string, int or float64 value. The interface
	// returned may be used in a type switch.
	// (A Value itself is not amenable to type switching, since the types that
	// satisfy it in this package are not exported.)
	Raw() interface{}
}

type ValueLoop interface {
	// Strings returns this value as a []string. If its underlying type is
	// not []string, then it is converted to a string and returned.
	Strings() []string

	// Ints returns this value as a []int. If its underlying type is
	// not []int, then nil is returned.
	Ints() []int

	// Floats returns this value as a []float64. If its underlying type is
	// []int, then a new slice is returned with the integers converted to
	// floats. If its underlying type is []string, then nil is returned.
	Floats() []float64

	// Raw provides the underlying []string, []int or []float64 value. The
	// interface returned may be used in a type switch.
	// (A ValueLoop itself is not amenable to type switching, since the types
	// that satisfy it in this package are not exported.)
	Raw() interface{}
}