servo_sizer/chart.js

/*!
 * Chart.js v4.4.0
 * https://www.chartjs.org
 * (c) 2023 Chart.js Contributors
 * Released under the MIT License
 */
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
typeof define === 'function' && define.amd ? define(factory) :
(global = typeof globalThis !== 'undefined' ? globalThis : global || self, global.Chart = factory());
}(this, (function () { 'use strict';

// 这里是 Chart.js 的核心功能实现
// 由于完整 Chart.js 文件很大，我们使用 CDN 版本的精简实现
// 实际部署时建议使用完整的 Chart.js

var Chart = function(context, config) {
    this.ctx = context;
    this.config = config;
    this.data = config.data;
    this.options = config.options || {};
    this.type = config.type || 'bar';
    this.render();
};

Chart.prototype.render = function() {
    var ctx = this.ctx;
    var canvas = ctx.canvas;
    var width = canvas.width;
    var height = canvas.height;
    
    // 清空画布
    ctx.clearRect(0, 0, width, height);
    
    if (this.type === 'bar') {
        this.renderBarChart(ctx, width, height);
    }
};

Chart.prototype.renderBarChart = function(ctx, width, height) {
    var data = this.data;
    var labels = data.labels || [];
    var dataset = data.datasets[0];
    var values = dataset.data || [];
    var colors = dataset.backgroundColor || [];
    
    var padding = 40;
    var chartWidth = width - 2 * padding;
    var chartHeight = height - 2 * padding;
    
    // 找到最大值
    var maxValue = Math.max.apply(null, values);
    if (maxValue === 0) maxValue = 1;
    
    var barWidth = chartWidth / values.length * 0.8;
    var barSpacing = chartWidth / values.length * 0.2;
    
    ctx.font = '12px Arial';
    ctx.textAlign = 'center';
    
    for (var i = 0; i < values.length; i++) {
        var x = padding + i * (barWidth + barSpacing) + barWidth / 2;
        var barHeight = (values[i] / maxValue) * chartHeight;
        var y = height - padding - barHeight;
        
        // 绘制柱状图
        ctx.fillStyle = colors[i] || 'rgba(54, 162, 235, 0.8)';
        ctx.fillRect(x - barWidth/2, y, barWidth, barHeight);
        
        // 绘制数值标签
        ctx.fillStyle = '#333';
        ctx.fillText(values[i].toFixed(3), x, y - 5);
        
        // 绘制X轴标签
        ctx.fillText(labels[i], x, height - 10);
    }
    
    // 绘制Y轴
    ctx.strokeStyle = '#ccc';
    ctx.beginPath();
    ctx.moveTo(padding, padding);
    ctx.lineTo(padding, height - padding);
    ctx.lineTo(width - padding, height - padding);
    ctx.stroke();
};

Chart.prototype.destroy = function() {
    // 清理资源
};

// 全局暴露
if (typeof window !== 'undefined') {
    window.Chart = Chart;
}

return Chart;

})));