// Package metrics is an interface for instrumentation.
package metrics

type Fields map[string]string

// Metrics provides a way to instrument application data
type Metrics interface {
	Counter(id string) Counter
	Gauge(id string) Gauge
	Histogram(id string) Histogram
	String() string
}

type Counter interface {
	// Increment by the given value
	Incr(d uint64)
	// Decrement by the given value
	Decr(d uint64)
	// Reset the counter
	Reset()
	// Label the counter
	WithFields(f Fields) Counter
}

type Gauge interface {
	// Set the gauge value
	Set(d int64)
	// Reset the gauge
	Reset()
	// Label the gauge
	WithFields(f Fields) Gauge
}

type Histogram interface {
	// Record a timing
	Record(d int64)
	// Reset the histogram
	Reset()
	// Label the histogram
	WithFields(f Fields) Histogram
}