var overlayControl = gantt.ext.overlay;
var today = new Date();
var return_first;

var sCurvePayload = {
	period: 'week',
	project_id: proyekId
};

function thousandSeparator(x) {
    return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ".");
}

function callback(response) {
	return_first = response;
}

function getSCurveData(){
	$.ajax({
		headers: {
			"Content-Type": "application/json",
			"Authorization": `Bearer ${token}`
		},
		url: `${base_url}project/get-s-curve`,
		type: "POST",
		data:JSON.stringify(sCurvePayload),
		success: function (data) {
			callback(data)
		}
	});
};

function toggleOverlay() {
	if(overlayControl.isOverlayVisible(lineOverlay)){
		gantt.config.readonly = false;
		overlayControl.hideOverlay(lineOverlay);
		gantt.$root.classList.remove("overlay_visible");
	}else{
		gantt.config.readonly = true;
		overlayControl.showOverlay(lineOverlay);
		gantt.$root.classList.add("overlay_visible");
	}
}

function getChartScaleRange(){
	var tasksRange = gantt.getSubtaskDates();
	var cells = [];
	var scale = gantt.getScale();
	if(!tasksRange.start_date){
		return scale.trace_x;
	}

	scale.trace_x.forEach(function(date){
		if(date >= tasksRange.start_date && date <= tasksRange.end_date){
			cells.push(date);
		}
	});
	return cells;
}

function getProgressLine(){
	// As long as the progress data length is same with chart scale range (period) then it's fine.
	getSCurveData();
	var cumulativePlannedDurations = return_first.data[0].data.percentagePlan;
	var cumulativeRealDurations = return_first.data[0].data.percentageReal;
	var bcwpCumulative = return_first.data[0].data.bcwp;
	return {planned: cumulativePlannedDurations, real: cumulativeRealDurations, bcwp: bcwpCumulative};
}

function getScalePaddings(){
	var scale = gantt.getScale();
	var dataRange = gantt.getSubtaskDates();

	var chartScale = getChartScaleRange();
	var newWidth = scale.col_width;
	var padding = {
		left:0,
		right:0
	};

	if(dataRange.start_date){
		var yScaleLabelsWidth = 48;
		// fine tune values in order to align chart with the scale range
		padding.left = gantt.posFromDate(dataRange.start_date) - yScaleLabelsWidth;
		padding.right = scale.full_width - gantt.posFromDate(dataRange.end_date) - yScaleLabelsWidth;
		padding.top = gantt.config.row_height - 12;
		padding.bottom = gantt.config.row_height - 12;
	}
	return padding;
}

var myChart;
var lineOverlay = overlayControl.addOverlay(function(container) {

	var scaleLabels = [];

	var chartScale = getChartScaleRange();

	chartScale.forEach(function(date){
		scaleLabels.push(dateToStr(date));
	});

	var values = getProgressLine();

	var canvas = document.createElement("canvas");
	container.appendChild(canvas);
	canvas.style.height = container.offsetHeight + "px";
	canvas.style.width = container.offsetWidth + "px";

	var ctx = canvas.getContext("2d");
	if(myChart){
		myChart.destroy();
	}
	myChart = new Chart(ctx, {
		type: "line",
		data: {
			datasets: [
				{
					label: "Planned progress",
					backgroundColor: "#001eff",
					borderColor: "#001eff",
					data: values.planned,
					fill: false,
					cubicInterpolationMode: 'default'
				},
				{
					label: "Real progress",
					backgroundColor: "#f51b1b",
					borderColor: "#f51b1b",
					data: values.real,
					fill: false,
					cubicInterpolationMode: 'monotone'
				},
			]
		},
		options: {
			responsive: true,
			maintainAspectRatio: false,
			layout: {
				padding: getScalePaddings()
			},
			onResize: function(chart, newSize) {
				var dataRange = gantt.getSubtaskDates();
				if(dataRange.start_date){
					// align chart with the scale range
					chart.options.layout.padding = getScalePaddings();
				}
			},
			legend: {
				display: false
			},
			tooltips: {
				enabled: false,
				custom: function(tooltipModel, dataItem) {
					// Tooltip Element
					var tooltipEl = document.getElementById('chartjs-tooltip');

					// Create element on first render
					if (!tooltipEl) {
						tooltipEl = document.createElement('div');
						tooltipEl.id = 'chartjs-tooltip';
						tooltipEl.innerHTML = "<table></table>";
						document.body.appendChild(tooltipEl);
					}

					// Hide if no tooltip
					if (tooltipModel.opacity === 0) {
						tooltipEl.style.opacity = 0;
						return;
					}

					// Set caret Position
					tooltipEl.classList.remove('above', 'below', 'no-transform');
					if (tooltipModel.yAlign) {
						tooltipEl.classList.add(tooltipModel.yAlign);
					} else {
						tooltipEl.classList.add('no-transform');
					}

					function getBody(bodyItem) {
						return bodyItem.lines;
					}

					// Set Text
					if (tooltipModel.body) {
						var titleLines = tooltipModel.title || [];
						var bodyLines = tooltipModel.body.map(getBody);

						var innerHtml = '<thead>';

						titleLines.forEach(function(title) {
							innerHtml += '<tr><th>' + title + '</th></tr>';
						});
						innerHtml += '</thead><tbody>';

						bodyLines.forEach(function(body, i) {
							var colors = tooltipModel.labelColors[i];
							var style = 'background:' + colors.backgroundColor;
							style += '; border-color:' + colors.borderColor;
							style += '; border-width: 2px';
							var span = '<span style="' + style + '"></span>';
							innerHtml += '<tr><td>' + "<span style='color: #001eff'>Planned Progress</span> : " + values.planned[tooltipModel.dataPoints[0].index] + '%</td></tr>';
							innerHtml += '<tr><td>' + "<span style='color: #f51b1b'>Actual Progress</span> : " + values.real[tooltipModel.dataPoints[0].index] + '%</td></tr>';
							innerHtml += '<tr><td>&nbsp</td></tr>';
							innerHtml += '<tr><td>' + "BCWP :" + '</td></tr>';
							// someone pls change this hard coded currency later
							innerHtml += '<tr><td>Rp. ' + thousandSeparator(values.bcwp[tooltipModel.dataPoints[0].index]) + '</td></tr>';
						});
						innerHtml += '</tbody>';

						var tableRoot = tooltipEl.querySelector('table');
						tableRoot.innerHTML = innerHtml;
					}

					// `this` will be the overall tooltip
					var position = this._chart.canvas.getBoundingClientRect();

					// Display, position, and set styles for font
					tooltipEl.style.opacity = 1;
					tooltipEl.style.zIndex= 99999;
					tooltipEl.style.position = 'absolute';
					tooltipEl.style.left = position.left + window.pageXOffset + tooltipModel.caretX + -160 + 'px';
					tooltipEl.style.top = position.top + window.pageYOffset + tooltipModel.caretY + -130 + 'px';
					tooltipEl.style.fontFamily = tooltipModel._bodyFontFamily;
					tooltipEl.style.color= "#000000";
					tooltipEl.style.fontSize = tooltipModel.bodyFontSize + 'px';
					tooltipEl.style.fontStyle = tooltipModel._bodyFontStyle;
					tooltipEl.style.padding = tooltipModel.yPadding + 'px ' + tooltipModel.xPadding + 'px';
					tooltipEl.style.pointerEvents = 'none';
					tooltipEl.style.backgroundColor = 'rgba(238,238,238,0.9)';
				}
			},
			hover: {
				mode: "nearest",
				intersect: true
			},
			scales: {
				xAxes: [{
					labels: scaleLabels,
					gridLines:{
						display: false
					},
					ticks: {
						display: false
					}
				},
					{
						position:"top",
						labels: scaleLabels,
						gridLines:{
							display: false
						},
						ticks: {
							display: false
						}
					}
				],
				yAxes: [{
					display: true,
					gridLines: {
						display:false
					},
					ticks: {
						display: true,
						min: 0,
						max: 100,
						stepSize: 10,
						callback: function(current) {
							if (current > 100) {return "";}
							return current + "%";
						}
					}
				},
					{
						display: true,
						position: "right",
						gridLines: {
							display:false
						},
						ticks: {
							display: true,
							min: 0,
							max: 100,
							stepSize: 10,
							callback: function(current) {
								if (current > 100) {return "";}
								return current + "%";
							}
						}}
				]
			}
		}
	});
	return canvas;
});