07. Distance-Converter

function attachEventsListeners() {
    document.getElementById('convert').addEventListener('click', convert);
    function convert(){
        let inputDistance = Number(document.getElementById('inputDistance').value);
        let outputDistance = document.getElementById('outputDistance');

        let inputUnits = document.getElementById('inputUnits');
        let convertFrom = inputUnits.options[inputUnits.selectedIndex].value;
        let outputUnits = document.getElementById('outputUnits');
        let convertTo = outputUnits.options[outputUnits.selectedIndex].value;

        switch (convertFrom)
        {
            case 'km': inputDistance = inputDistance * 1000; break;
            case 'm': inputDistance = inputDistance; break;
            case 'cm': inputDistance = inputDistance * 0.01; break;
            case 'mm': inputDistance = inputDistance * 0.001; break;
            case 'mi': inputDistance = inputDistance * 1609.34; break;
            case 'yrd': inputDistance = inputDistance * 0.9144; break;
            case 'ft': inputDistance = inputDistance * 0.3048; break;
            case 'in': inputDistance = inputDistance * 0.0254; break;
            default:console.log(inputDistance);
        }
        switch (convertTo)
        {
            case 'km': outputDistance.value = inputDistance / 1000; break;
            case 'm': outputDistance.value = inputDistance; break;
            case 'cm': outputDistance.value = inputDistance / 0.01; break;
            case 'mm': outputDistance.value = inputDistance / 0.001; break;
            case 'mi': outputDistance.value = inputDistance / 1609.34; break;
            case 'yrd': outputDistance.value = inputDistance / 0.9144; break;
            case 'ft': outputDistance.value = inputDistance / 0.3048; break;
            case 'in': outputDistance.value = inputDistance / 0.0254; break;
            default:console.log(inputDistance);
        }
    }
}