package hal

import "fmt"

func NewMockIO(inputs ...float64) *MockIO {
	return &MockIO{
		Inputs: inputs,
	}
}

type MockIO struct {
	currentInputIndex int
	Inputs            []float64
	Outputs           []float64
}

func (io *MockIO) increaseInputIndex() {
	io.currentInputIndex++
}

func (io *MockIO) Read() (float64, error) {
	if len(io.Inputs) <= io.currentInputIndex {
		return 0, fmt.Errorf("no mock data for index %d", io.currentInputIndex)
	}
	defer io.increaseInputIndex()
	return io.Inputs[io.currentInputIndex], nil
}

func (io *MockIO) Write(output float64) error {
	io.Outputs = append(io.Outputs, output)
	return nil
}