let slideShowInterval = null

/**
 * Sets listener and attributes on model-viewer to
 * allow for click registering of a new hotspot
 */
readyAddHotspot = function() {
    const previewMv = $('model-viewer')
    previewMv.one('click', clickAddHotspot)
    previewMv.addClass('AddingHotspot')
    previewMv[0].disableTap = true
}

/**
 * Event listener callback to retrieve the info
 * about the model surface point selected by the
 * mouse and add that information to the editor
 * text input
 * 
 * @param {PointerEvent} e 
 */
clickAddHotspot = function(e) {
    const previewMv = $('model-viewer')
    previewMv.removeClass('AddingHotspot')
    let hsPosition = null
    let targetModel = previewMv[0]
    targetModel.disableTap = false
    if (targetModel) {
        hsPosition = targetModel.positionAndNormalFromPoint(e.clientX, e.clientY)
    }
    if (hsPosition) {
        let currentText = $('#wpTextbox1').val()
        let extractMetadata = currentText.match(/<pre>([\S\s]*?)<\/pre>/)
        let metadata = (extractMetadata.length >= 2) ? JSON.parse(extractMetadata[1]) : {viewerConfig: {}, annotations: {}, annotationSets: {}}
        if (metadata.annotations === undefined) {
            metadata.annotations = {}
        }
        let hsOutput = {}
        hsOutput['data-position'] = hsPosition.position.toString().replaceAll(/(\d{5})(\d*?m)/g,"$1m")
        hsOutput['data-normal'] = hsPosition.normal.toString().replaceAll(/(\d{5})(\d*?m)/g,"$1m")
        let orbitObj = targetModel.getCameraOrbit()
        hsOutput['data-orbit'] = `${orbitObj.theta.toFixed(2)}rad ${orbitObj.phi.toFixed(2)}rad ${orbitObj.radius.toFixed(2)}m`
        let targetObj = targetModel.getCameraTarget()
        hsOutput['data-target'] = `${targetObj.x.toFixed(5)}m ${targetObj.y.toFixed(5)}m ${targetObj.z.toFixed(5)}m`
        //navigator.clipboard.writeText(JSON.stringify(hsOutput, null, 2));
        metadata.annotations['New Hotspot'] = hsOutput
        let newText = currentText.replace(/(.*?<pre>)[\S\s]*?(<\/pre>.*)/,`$1\n${JSON.stringify(metadata, null, 2)}\n$2`)
        $('#wpTextbox1').val(newText)
    }
}

/**
 * Event listener callback to toggle the visibility
 * of a hotspot's annotation when the hotspot is 
 * clicked
 * 
 * @param {PointerEvent} e 
 */
onAnnotation = function(e) {
	e.stopPropagation()
	let targetAnnotation = Number.parseInt(e.target.slot.split('-')[1])
	let targetModel = e.target.closest('model-viewer')
    selectAnnotation(targetModel, targetAnnotation)
}

/**
 * Event listener callback to hide all hotspot
 * annotations when the model-viewer receives
 * a click event
 */
clearAnnotations = function() {
	[...document.getElementsByClassName('HotspotAnnotation')].forEach( an => {
		an.classList.add('HiddenAnnotation')
	})
};

/**
 * Select the numbered hotspot of the given model
 * 
 * @param {ModelViewer} mView
 * @param {number} annotId
 * 
 * @return {bool} true if annotation selected false if unselected
 */
selectAnnotation = function(mView, annotId) {
    let anSelected = false;
    [...mView.querySelectorAll('.HotspotAnnotation')].forEach( (an, idx) => {
		if (idx + 1 == annotId && an.classList.contains('HiddenAnnotation')) {
			an.classList.remove('HiddenAnnotation');
			if (an.parentElement.dataset.target) {mView.cameraTarget = an.parentElement.dataset.target}
			if (an.parentElement.dataset.orbit) {mView.cameraOrbit = an.parentElement.dataset.orbit}
            anSelected = true
		} else {
			an.classList.add('HiddenAnnotation');
		}        
	});
    return anSelected
}

/**
 * Select the next numbered hotspot
 * 
 * @param {ModelViewer} mView
 * 
 * @return {number} ID number of the newly selected hotspot
 */
nextAnnotation = function(mView) {
    let incrAnnotation = 0
    const numSpots = [...mView.querySelectorAll('Button')].length
    const currentAnnotation = mView.querySelectorAll('Button:has(.HotspotAnnotation:not(.HiddenAnnotation))')[0]
    if (!currentAnnotation) {
        incrAnnotation = 1
    } else {
        const annotationId = Number.parseInt(currentAnnotation.slot.split('-')[1])
        incrAnnotation = (annotationId >= numSpots)
            ? 1
            : annotationId + 1
    }
    selectAnnotation(mView, incrAnnotation)
    return incrAnnotation
}

/**
 * Select the previous numbered hotspot
 * 
 * @param {ModelViewer} mView
 * 
 * @return {number} ID number of the newly selected hotspot
 */
prevAnnotation = function(mView) {
    let decrAnnotation = 0
    const numSpots = [...mView.querySelectorAll('Button')].length
    const currentAnnotation = mView.querySelectorAll('Button:has(.HotspotAnnotation:not(.HiddenAnnotation))')[0]
    if (!currentAnnotation) {
        decrAnnotation = numSpots
    } else {
        const annotationId = Number.parseInt(currentAnnotation.slot.split('-')[1])
        decrAnnotation = (annotationId <= 1)
            ? numSpots
            : annotationId - 1
    }
    selectAnnotation(mView, decrAnnotation)
    return decrAnnotation
}

/**
 * Cycle through the available annotations
 * 
 * @param {ModelViewer} mView
 * 
 * @param {Number} [slideDuration = 5000]
 * 
 * @return {intervalID} ID of the created interval timer
 */
slideshowAnnotations = function(mView, slideDuration = 5000) {
    if (slideShowInterval) {
        clearInterval(slideShowInterval)
    } else {
        nextAnnotation(mView)
        slideShowInterval = setInterval(nextAnnotation, slideDuration, mView)
    }
}