// @license magnet:?xt=urn:btih:0b31508aeb0634b347b8270c7bee4d411b5d4109&dn=agpl-3.0.txt AGPL-3.0
'use strict';
/* globals Chart */

function initCharts() {
	if (!window.Chart) {
		if (window.console) {
			console.log('FreshRSS is waiting for Chart.js…');
		}
		window.setTimeout(initCharts, 25);
		return;
	}

	const jsonData = document.getElementsByClassName('jsonData-stats');

	let jsonDataParsed;
	let chartConfig;

	for (let i = 0; i < jsonData.length; i++) {
		jsonDataParsed = JSON.parse(jsonData[i].innerHTML);

		switch (jsonDataParsed.charttype) {
			case 'bar':
				chartConfig = jsonChartBar(jsonDataParsed.label, jsonDataParsed.data, jsonDataParsed.xAxisLabels);
				break;
			case 'doughnut':
				chartConfig = jsonChartDoughnut(jsonDataParsed.labels, jsonDataParsed.data);
				break;
			case 'barWithAverage':
				chartConfig = jsonChartBarWithAverage(jsonDataParsed.labelBarChart, jsonDataParsed.dataBarChart,
					jsonDataParsed.labelAverage, jsonDataParsed.dataAverage, jsonDataParsed.xAxisLabels);
		}

		/* eslint-disable no-new */
		new Chart(document.getElementById(jsonDataParsed.canvasID), chartConfig);
		/* eslint-enable no-new */
	}

	// Force resize after clicking enlarge button (needed since chart.js v4)
	for (const id in Chart.instances) {
		const instance = Chart.instances[id];
		const boxTitle = instance.canvas.parentElement.previousElementSibling;
		const enlargeBtns = boxTitle.querySelectorAll('a.btn');

		function forceResize() {
			function waitHash() {
				requestAnimationFrame(() => instance.resize());
				window.removeEventListener('hashchange', waitHash);
			}
			instance.resize(); // try early resize
			window.addEventListener('hashchange', waitHash);
		}
		for (const btn of enlargeBtns) {
			btn.addEventListener('click', forceResize);
		}
	}

	window.addEventListener('resize', () => {
		for (const id in Chart.instances) {
			const instance = Chart.instances[id];

			// Workaround for a chart.js bug which makes the canvas blurry if
			// page was loaded with very low zoom level and later zoomed in
			instance.update();
			instance.resize();
		}
	});

	if (window.console) {
		console.log('Chart.js finished');
	}
}

function jsonChartBar(label, data, xAxisLabels = '') {
	return {
		type: 'bar',
		data: {
			labels: xAxisLabels,
			datasets: [{
				label,
				backgroundColor: '#0062BD',
				borderColor: '#0062BD',
				data,
				barPercentage: 1.0,
				categoryPercentage: 1.0,
				order: 2,
			}],
		},
		options: {
			scales: {
				y: {
					beginAtZero: true,
				},
				x: {
					grid: {
						display: false,
					},
				},
			},
			plugins: {
				legend: {
					display: false,
				},
			},
		},
	};
}

function jsonChartDoughnut(labels, data) {
	return {
		type: 'doughnut',
		data: {
			labels,
			datasets: [{
				backgroundColor: [
					'#0b84a5', // petrol
					'#f6c85f', // sand
					'#6f4e7c', // purple
					'#9dd866', // green
					'#ca472f', // red
					'#ffa056', // orange
					'#8dddd0', // turkis
					'#f6c85f', // sand
					'#6f4e7c', // purple
					'#9dd866', // green
					'#ca472f', // red
					'#ffa056', // orange
					'#8dddd0', // turkis
				],
				data,
			}],
		},
		options: {
			layout: {
				padding: 20,
			},
			plugins: {
				legend: {
					position: 'bottom',
					align: 'start',
				},
			},
		},
	};
}

function jsonChartBarWithAverage(labelBarChart, dataBarChart, labelAverage, dataAverage, xAxisLabels = '') {
	return {
		type: 'bar',
		data: {
			datasets: [
				{
					// bar chart layout
					label: labelBarChart,
					backgroundColor: '#0062BD',
					borderColor: '#0062BD',
					data: dataBarChart,
					barPercentage: 1.0,
					categoryPercentage: 1.0,
					order: 2,
				},
				{
					// average line chart
					type: 'line',
					label: labelAverage, // Todo: i18n
					borderColor: 'rgb(192,216,0)',
					data: {
						'-30': dataAverage,
						'-1': dataAverage,
					},
					order: 1,
				},
			],
		},

		options: {
			scales: {
				y: {
					beginAtZero: true,
				},
				x: {
					ticks: {
						callback: function (val) {
							if (xAxisLabels.length > 0) {
								return xAxisLabels[val];
							} else {
								return val;
							}
						},
					},
					grid: {
						display: false,
					},
				},
			},
			elements: {
				point: {
					radius: 0,
				},
			},
			plugins: {
				tooltip: {
					callbacks: {
						title: function (tooltipitem) {
							if (xAxisLabels.length > 0) {
								return xAxisLabels[tooltipitem[0].dataIndex];
							} else {
								return tooltipitem[0].label;
							}
						},
					},
				},
				legend: {
					display: false,
				},
			},
		},
	};
}

initCharts();

// @license-end