const WeatherChart = {
	chart: null,

	display(historyData = [], forecastData = []) {
		historyData = Array.isArray(historyData) ? historyData : [];
		forecastData = Array.isArray(forecastData) ? forecastData : [];
		
		if (historyData.length === 0 && forecastData.length === 0) {
			return;
		}
		
		const allLabels = [...new Set([
			...historyData.map(item => item.date_time),
			...forecastData.map(item => item.date_time)
		])].sort();

		const historyTemperatures = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item ? item.temperature : null;
		});
		const historyHumidities = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item ? item.humidity : null;
		});
		const historyPressures = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item ? item.pressure : null;
		});
		const historyWindSpeeds = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item ? item.wind_speed : null;
		});
		const historyRainfalls = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item ? item.rainfall : null;
		});
		const historyRainTotals = allLabels.map(label => {
			const item = historyData.find(d => d.date_time === label);
			return item && item.rain_total !== undefined ? item.rain_total : null;
		});

		const byTime = new Map();
		forecastData.forEach(fp => {
			if (!byTime.has(fp.date_time)) byTime.set(fp.date_time, {});
			const bucket = byTime.get(fp.date_time);
			const h = typeof fp.lead_hours === 'number' ? fp.lead_hours : null;
			if (h !== null && h >= 0 && h <= 3) {
				bucket[h] = fp;
			}
		});

		const getRainAtLead = (label, lead) => {
			const b = byTime.get(label);
			if (!b || !b[lead]) return null;
			return b[lead].rainfall != null ? b[lead].rainfall : null;
		};
		const getTempAtLead0 = (label) => {
			const b = byTime.get(label);
			if (!b || !b[0]) return null;
			return b[0].temperature != null ? b[0].temperature : null;
		};

		const forecastRainfallsH0 = allLabels.map(label => getRainAtLead(label, 0));
		const forecastRainfallsH1 = allLabels.map(label => getRainAtLead(label, 1));
		const forecastRainfallsH2 = allLabels.map(label => getRainAtLead(label, 2));
		const forecastRainfallsH3 = allLabels.map(label => getRainAtLead(label, 3));

		const pickNearest = (label, field) => {
			const b = byTime.get(label);
			if (!b) return null;
			if (b[0] && b[0][field] != null) return b[0][field];
			if (b[1] && b[1][field] != null) return b[1][field];
			if (b[2] && b[2][field] != null) return b[2][field];
			if (b[3] && b[3][field] != null) return b[3][field];
			return null;
		};
		const forecastTemperaturesNearest = allLabels.map(label => pickNearest(label, 'temperature'));
		const forecastHumiditiesNearest = allLabels.map(label => pickNearest(label, 'humidity'));
		const forecastPressuresNearest = allLabels.map(label => pickNearest(label, 'pressure'));
		const forecastWindSpeedsNearest = allLabels.map(label => pickNearest(label, 'wind_speed'));

		if (this.chart) this.chart.destroy();

		const datasets = [
			{
				label: '温度 (°C) - 实测',
				seriesKey: 'temp_actual',
				data: historyTemperatures,
				borderColor: 'rgb(255, 99, 132)',
				backgroundColor: 'rgba(255, 99, 132, 0.1)',
				yAxisID: 'y-temperature',
				tension: 0.4,
				spanGaps: false
			},
			{
				label: '湿度 (%) - 实测',
				seriesKey: 'hum_actual',
				data: historyHumidities,
				borderColor: 'rgb(54, 162, 235)',
				backgroundColor: 'rgba(54, 162, 235, 0.1)',
				yAxisID: 'y-humidity',
				tension: 0.4,
				hidden: true,
				spanGaps: false
			},
			{
				label: '大气压 (hPa) - 实测',
				seriesKey: 'pressure_actual',
				data: historyPressures,
				borderColor: 'rgb(153, 102, 255)',
				backgroundColor: 'rgba(153, 102, 255, 0.1)',
				yAxisID: 'y-pressure',
				tension: 0.4,
				hidden: true,
				spanGaps: false
			},
			{
				label: '风速 (m/s) - 实测',
				seriesKey: 'wind_actual',
				data: historyWindSpeeds,
				borderColor: 'rgb(75, 192, 192)',
				backgroundColor: 'rgba(75, 192, 192, 0.1)',
				yAxisID: 'y-wind',
				tension: 0.4,
				hidden: true,
				spanGaps: false
			},
			{
				label: '雨量 (mm) - 实测',
				seriesKey: 'rain_actual',
				data: historyRainfalls,
				type: 'bar',
				backgroundColor: 'rgba(54, 162, 235, 0.6)',
				borderColor: 'rgb(54, 162, 235)',
				yAxisID: 'y-rainfall'
			},
			{
				label: '累计雨量 (mm) - 实测',
				seriesKey: 'rain_total',
				data: historyRainTotals,
				borderColor: 'rgb(75, 192, 192)',
				backgroundColor: 'rgba(75, 192, 192, 0.1)',
				yAxisID: 'y-rainfall',
				tension: 0.2,
				spanGaps: false,
				pointRadius: 0,
				hidden: true
			}
		];

		if (forecastData.length > 0) {
			datasets.push(
				{ label: '雨量 (mm) - 预报 (+1h)', seriesKey: 'rain_fcst_h1', data: forecastRainfallsH1, type: 'bar', backgroundColor: 'rgba(255, 99, 71, 0.55)', borderColor: 'rgb(255, 99, 71)', yAxisID: 'y-rainfall' },
				{ label: '雨量 (mm) - 预报 (+2h)', seriesKey: 'rain_fcst_h2', data: forecastRainfallsH2, type: 'bar', backgroundColor: 'rgba(255, 205, 86, 0.55)', borderColor: 'rgb(255, 205, 86)', yAxisID: 'y-rainfall' },
				{ label: '雨量 (mm) - 预报 (+3h)', seriesKey: 'rain_fcst_h3', data: forecastRainfallsH3, type: 'bar', backgroundColor: 'rgba(76, 175, 80, 0.55)', borderColor: 'rgb(76, 175, 80)', yAxisID: 'y-rainfall' }
			);

			datasets.push(
				{
					label: '温度 (°C) - 预报',
					seriesKey: 'temp_fcst',
					data: forecastTemperaturesNearest,
					borderColor: 'rgb(255, 159, 64)',
					backgroundColor: 'rgba(255, 159, 64, 0.1)',
					borderDash: [5, 5],
					yAxisID: 'y-temperature',
					tension: 0.4,
					spanGaps: false,
					hidden: true
				},
				{
					label: '湿度 (%) - 预报',
					seriesKey: 'hum_fcst',
					data: forecastHumiditiesNearest,
					borderColor: 'rgb(54, 162, 235)',
					backgroundColor: 'rgba(54, 162, 235, 0.1)',
					borderDash: [5, 5],
					yAxisID: 'y-humidity',
					tension: 0.4,
					hidden: true,
					spanGaps: false
				},
				{
					label: '大气压 (hPa) - 预报',
					seriesKey: 'pressure_fcst',
					data: forecastPressuresNearest,
					borderColor: 'rgb(153, 102, 255)',
					backgroundColor: 'rgba(153, 102, 255, 0.1)',
					borderDash: [5, 5],
					yAxisID: 'y-pressure',
					tension: 0.4,
					hidden: true,
					spanGaps: false
				},
				{
					label: '风速 (m/s) - 预报',
					seriesKey: 'wind_fcst',
					data: forecastWindSpeedsNearest,
					borderColor: 'rgb(75, 192, 192)',
					backgroundColor: 'rgba(75, 192, 192, 0.1)',
					borderDash: [5, 5],
					yAxisID: 'y-wind',
					tension: 0.4,
					hidden: true,
					spanGaps: false
				}
			);
		}

		const ctx = document.getElementById('combinedChart').getContext('2d');
		const chartConfig = {
			type: 'line',
			data: {
				labels: allLabels,
				datasets: datasets
			},
			options: {
				responsive: true,
				maintainAspectRatio: false,
				interaction: { mode: 'index', intersect: false },
				layout: { padding: { top: 12, right: 16, bottom: 12, left: 16 } },
				plugins: {
					legend: {
						display: true,
						position: 'top',
						align: 'center',
						labels: {
							padding: 16
						}
					}
				},
				scales: {
					'y-temperature': { 
						type: 'linear', 
						display: true, 
						position: 'right', 
						title: { display: true, text: '温度 (°C)' } 
					},
					'y-humidity': { 
						type: 'linear', 
						display: true, 
						position: 'right', 
						title: { display: true, text: '湿度 (%)' }, 
						grid: { drawOnChartArea: false }, 
						min: 0, 
						max: 100 
					},
					'y-pressure': { 
						type: 'linear', 
						display: true, 
						position: 'left', 
						title: { display: true, text: '大气压 (hPa)' }, 
						grid: { drawOnChartArea: false }
					},
					'y-wind': { 
						type: 'linear', 
						display: true, 
						position: 'left', 
						title: { display: true, text: '风速 (m/s)' }, 
						grid: { drawOnChartArea: false }, 
						beginAtZero: true 
					},
					'y-rainfall': { 
						type: 'linear', 
						display: true, 
						position: 'right', 
						title: { display: true, text: '雨量 (mm)' }, 
						grid: { drawOnChartArea: false }, 
						beginAtZero: true 
					}
				}
			}
		};

		this.chart = new Chart(ctx, chartConfig);

		const mode = document.getElementById('legendMode')?.value || 'combo_standard';
		this.applyLegendMode(mode);
	}
};

WeatherChart.applyLegendMode = function(mode) {
	if (!this.chart) return;

	// 设置数据集可见性
	const map = new Map();
	this.chart.data.datasets.forEach(ds => {
		if (ds.seriesKey) map.set(ds.seriesKey, ds);
	});

	const setVisible = (keys) => {
		const allKeys = ['temp_actual','hum_actual','rain_actual','rain_total','temp_fcst','hum_fcst','pressure_actual','pressure_fcst','wind_actual','wind_fcst','rain_fcst_h1','rain_fcst_h2','rain_fcst_h3'];
		allKeys.forEach(k => { if (map.has(k)) map.get(k).hidden = true; });
		keys.forEach(k => { if (map.has(k)) map.get(k).hidden = false; });
	};

	switch (mode) {
		case 'combo_compact':
			setVisible(['temp_actual','hum_actual','rain_actual','rain_fcst_h1']);
			break;
		case 'verify_all':
			setVisible(['temp_actual','temp_fcst','hum_actual','hum_fcst','pressure_actual','pressure_fcst','wind_actual','wind_fcst','rain_actual','rain_fcst_h1','rain_fcst_h2','rain_fcst_h3']);
			break;
		case 'temp_compare':
			setVisible(['temp_actual','temp_fcst']);
			break;
		case 'hum_compare':
			setVisible(['hum_actual','hum_fcst']);
			break;
		case 'rain_all':
			setVisible(['rain_actual','rain_fcst_h1','rain_fcst_h2','rain_fcst_h3']);
			break;
		case 'pressure_compare':
			setVisible(['pressure_actual','pressure_fcst']);
			break;
		case 'wind_compare':
			setVisible(['wind_actual','wind_fcst']);
			break;
		case 'combo_standard':
		default:
			setVisible(['temp_actual','hum_actual','rain_actual','rain_fcst_h1','rain_fcst_h2','rain_fcst_h3']);
			break;
	}
	this.chart.update();
};

WeatherChart.updateAxesVisibility = function() {
	if (!this.chart) return;

	// 检查每个轴是否有可见的数据集
	const hasVisibleDatasets = (axisId) => {
		return this.chart.data.datasets.some(ds => !ds.hidden && ds.yAxisID === axisId);
	};

	// 更新每个轴的显示状态
	Object.entries(this.chart.options.scales).forEach(([scaleId, scale]) => {
		const shouldDisplay = hasVisibleDatasets(scaleId);
		if (scale.display !== shouldDisplay) {
			scale.display = shouldDisplay;
		}
	});
};

window.WeatherChart = WeatherChart;