/* eslint-disable @typescript-eslint/no-explicit-any */
import ChartJS, { ChartConfiguration, ChartConfigurationCustomTypesPerDataset } from 'chart.js/auto'
import { Color } from '../numbers'

export interface DatasetOptions {
    label: string
    color?: Color
}

export interface ChartConstructor {
    root: HTMLElement
    datasets: DatasetOptions[]
    maxDataSize?: number
    axisLabels?: { x: string, y: string }
    title?: string
    width?: number
}



/**
 * Creates a time series chart.
 * The x-axis is time and the y-axis is a number.
*/
export default class TimeSeries {
    // private data: {x: number, y: number}[] = []
    private chart: ChartJS<'line', number[], any>
    private width: number
    private maxDataSize: number

    constructor(opts: ChartConstructor) {

        const axisLabels = opts.axisLabels ?? { x: 'time', y: 'Y' }
        const title = opts.title ?? 'Time Series'

        this.maxDataSize = opts.maxDataSize ?? Infinity
        this.width = opts.width ?? 400

        const canvas = document.createElement('canvas')
        const draggable = document.createElement('drag-pane')
        draggable.setAttribute('heading', title )
        draggable.setAttribute('key', title)
        draggable.appendChild(canvas)
        opts.root.appendChild(draggable)
        canvas.width = this.width

        const datasets: ChartConfigurationCustomTypesPerDataset<'line', number[], any>['data']['datasets'] = opts.datasets.map((dataset) => {
            const borderColor = dataset.color?.toRGB() ?? Color.fromName('blue').toRGB()
            return {
                type: 'line',
                label: dataset.label,
                data: [],
                fill: false,
                borderColor,
                tension: 0.1
            }
        })

        const chartOptions: ChartConfiguration<'line', number[], any>  = {
            type: 'line',
            data: {
                labels: [],
                datasets
            },
            options: {
                scales: {
                    x: {
                        title: {
                            display: true,
                            text: axisLabels.x
                        }
                    },
                    y: {
                        title: {
                            display: true,
                            text: axisLabels.y
                        },
                        beginAtZero: true
                    }
                }
            }
        }

        this.chart = new ChartJS<'line', number[], any>(canvas, chartOptions)
    }

    /**
     * Pushes data to the chart.
     * The data should be an array of numbers, where each array corresponds to a dataset
     * in the order they were added.
     */
    public pushData(data: number[]): void {
        let didShift = false

        this.chart.data.datasets.forEach( dataset => {
            if (dataset.data.length > this.maxDataSize) {
                dataset.data.shift()
                didShift = true
            }
        })

        if (didShift) {
            this.chart.data.labels.shift()
        }

        this.chart.data.datasets.forEach((dataset, i) => {
            dataset.data.push(data[i])
        })

        this.chart.data.labels.push('')


        this.chart.update()
    }
}