@page "/charts/line"

<Block Title="Line 图" Introduction="使用 <code>OnInit</code> 回调委托方法，对初始化数据进行赋值后，即可进行绘图操作">
    <Chart @ref="LineChart" OnInitAsync="() => OnInit(0.4f, false)" OnAfterInitAsync="@OnAfterInit" OnAfterUpdateAsync="@OnAfterUpdate" />
    <div class="text-center mt-2 chart">
        <div class="btn-group">
            <button class="btn btn-primary" @onclick="e => Utility.RandomData(LineChart)"><i class="fa fa-line-chart"></i><span>随机数据</span></button>
            <button class="btn btn-primary" @onclick="e => Utility.AddDataSet(LineChart, ref LineDatasetCount)"><i class="fa fa-plus-circle"></i><span>添加数据集</span></button>
            <button class="btn btn-primary" @onclick="e => Utility.RemoveDataSet(LineChart, ref LineDatasetCount)"><i class="fa fa-minus-circle"></i><span>移除数据集</span></button>
            <button class="btn btn-primary" @onclick="e => Utility.AddData(LineChart, ref LineDataCount)"><i class="fa fa-plus"></i><span>添加数据</span></button>
            <button class="btn btn-primary" @onclick="e => Utility.RemoveData(LineChart, ref LineDataCount)"><i class="fa fa-minus"></i><span>移除数据</span></button>
        </div>
    </div>
    <BlockLogger @ref="Logger" class="mt-3" />
</Block>

<Block Title="Line 图" Introduction="使用设置 <code>ChartDataset</code> 实例的 <code>Tension</code> 参数，调整折线的曲率，默认位 <b>0.4f</b>">
    <Chart OnInitAsync="() => OnInit(0f, false)" />
</Block>

<Block Title="Line 图" Introduction="使用设置 <code>ChartDataset</code> 实例的 <code>Data</code> 参数中含 <code>null</code>，折线图使用虚线连接">
    <Chart OnInitAsync="() => OnInit(0f, true)" />
</Block>

<ChartToast />

// Copyright (c) Argo Zhang (argo@163.com). All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
// Website: https://www.blazor.zone or https://argozhang.github.io/

using BootstrapBlazor.Components;
using BootstrapBlazor.Shared.Pages.Components;
using System;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using System.Threading.Tasks;

namespace BootstrapBlazor.Shared.Pages.Charts
{
    /// <summary>
    /// 
    /// </summary>
    public partial class Line
    {
        private Random Randomer { get; } = new Random();
        private int LineDatasetCount = 2;
        private int LineDataCount = 7;

        [NotNull]
        private Chart? LineChart { get; set; }

        [NotNull]
        private BlockLogger? Logger { get; set; }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="firstRender"></param>
        protected override void OnAfterRender(bool firstRender)
        {
            base.OnAfterRender(firstRender);

            if (firstRender)
            {
                Logger.Log("Line 正在加载数据 ...");
            }
        }

        private Task OnAfterInit()
        {
            Logger.Log("Line 初始化完毕");
            return Task.CompletedTask;
        }

        private Task OnAfterUpdate(ChartAction action)
        {
            Logger.Log($"Line 图更新数据操作完毕 -- {action}");
            return Task.CompletedTask;
        }

        private Task<ChartDataSource> OnInit(float tension, bool hasNull)
        {
            var ds = new ChartDataSource();
            ds.Options.Title = "Line 折线图";
            ds.Options.X.Title = "天数";
            ds.Options.Y.Title = "数值";
            ds.Labels = Enumerable.Range(1, LineDataCount).Select(i => i.ToString());
            for (var index = 0; index < LineDatasetCount; index++)
            {
                ds.Data.Add(new ChartDataset()
                {
                    Tension = tension,
                    Label = $"数据集 {index}",
                    Data = Enumerable.Range(1, LineDataCount).Select((i, index) => (index == 2 && hasNull) ? null! : (object)Randomer.Next(20, 37))
                });
            }
            return Task.FromResult(ds);
        }
    }
}