import { action, computed, IReactionDisposer, observable, reaction } from 'mobx';
import { observer } from 'mobx-react';
import * as React from 'react';
// import d3
import * as d3 from 'd3';
import { Doc, DocListCast } from '../../../../../fields/Doc';
import { Id } from '../../../../../fields/FieldSymbols';
import { List } from '../../../../../fields/List';
import { listSpec } from '../../../../../fields/Schema';
import { Cast, DocCast } from '../../../../../fields/Types';
import { Docs } from '../../../../documents/Documents';
import { DocumentManager } from '../../../../util/DocumentManager';
import { LinkManager } from '../../../../util/LinkManager';
import { PinProps, PresBox } from '../../trails';
import { DataVizBox } from '../DataVizBox';
import { createLineGenerator, drawLine, minMaxRange, scaleCreatorNumerical, xAxisCreator, xGrid, yAxisCreator, yGrid } from '../utils/D3Utils';
import './Chart.scss';

export interface DataPoint {
    x: number;
    y: number;
}
interface SelectedDataPoint extends DataPoint {
    elem?: d3.Selection<d3.BaseType, unknown, SVGGElement, unknown>;
}
export interface LineChartProps {
    rootDoc: Doc;
    axes: string[];
    pairs: { [key: string]: any }[];
    width: number;
    height: number;
    dataDoc: Doc;
    fieldKey: string;
    margin: {
        top: number;
        right: number;
        bottom: number;
        left: number;
    };
}

@observer
export class LineChart extends React.Component<LineChartProps> {
    private _disposers: { [key: string]: IReactionDisposer } = {};
    private _lineChartRef: React.RefObject<HTMLDivElement> = React.createRef();
    private _lineChartSvg: d3.Selection<SVGGElement, unknown, null, undefined> | undefined;
    @observable _currSelected: SelectedDataPoint | undefined = undefined;
    // TODO: nda - some sort of mapping that keeps track of the annotated points so we can easily remove when annotations list updates

    @computed get _lineChartData() {
        if (this.props.axes.length <= 1) return [];
        return this.props.pairs
            ?.filter(pair => (!this.incomingLinks.length ? true : Array.from(Object.keys(pair)).some(key => pair[key] && key.startsWith('select'))))
            .map(pair => ({ x: Number(pair[this.props.axes[0]]), y: Number(pair[this.props.axes[1]]) }))
            .sort((a, b) => (a.x < b.x ? -1 : 1));
    }
    @computed get incomingLinks() {
        return LinkManager.Instance.getAllRelatedLinks(this.props.rootDoc) // out of all links
            .filter(link => link.anchor1 !== this.props.rootDoc) // get links where this chart doc is the target of the link
            .map(link => DocCast(link.anchor1)); // then return the source of the link
    }
    @computed get incomingSelected() {
        return this.incomingLinks // all links that are pointing to this node
            .map(anchor => DocumentManager.Instance.getFirstDocumentView(anchor)?.ComponentView as DataVizBox) // get their data viz boxes
            .filter(dvb => dvb)
            .map(dvb => dvb.pairs?.filter(pair => pair['select' + dvb.rootDoc[Id]])) // get all the datapoints they have selected field set by incoming anchor
            .lastElement();
    }
    @computed get rangeVals(): { xMin?: number; xMax?: number; yMin?: number; yMax?: number } {
        return minMaxRange([this._lineChartData]);
    }
    componentWillUnmount() {
        Array.from(Object.keys(this._disposers)).forEach(key => this._disposers[key]());
    }
    componentDidMount = () => {
        this._disposers.chartData = reaction(
            () => ({ dataSet: this._lineChartData, w: this.width, h: this.height }),
            ({ dataSet, w, h }) => {
                if (dataSet) {
                    this.drawChart([dataSet], this.rangeVals, w, h);
                    // redraw annotations when the chart data has changed, or the local or inherited selection has changed
                    this.clearAnnotations();
                    this._currSelected && this.drawAnnotations(Number(this._currSelected.x), Number(this._currSelected.y), true);
                    this.incomingSelected?.forEach((pair: any) => this.drawAnnotations(Number(pair[this.props.axes[0]]), Number(pair[this.props.axes[1]])));
                }
            },
            { fireImmediately: true }
        );
        this._disposers.annos = reaction(
            () => DocListCast(this.props.dataDoc[this.props.fieldKey + '-annotations']),
            annotations => {
                // modify how d3 renders so that anything in this annotations list would be potentially highlighted in some way
                // could be blue colored to make it look like anchor
                // this.drawAnnotations()
                // loop through annotations and draw them
                annotations.forEach(a => this.drawAnnotations(Number(a.x), Number(a.y)));
                // this.drawAnnotations(annotations.x, annotations.y);
            },
            { fireImmediately: true }
        );
        this._disposers.highlights = reaction(
            () => ({
                selected: this._currSelected,
                incomingSelected: this.incomingSelected,
            }),
            ({ selected, incomingSelected }) => {
                // redraw annotations when the chart data has changed, or the local or inherited selection has changed
                this.clearAnnotations();
                selected && this.drawAnnotations(Number(selected.x), Number(selected.y), true);
                incomingSelected?.forEach((pair: any) => this.drawAnnotations(Number(pair[this.props.axes[0]]), Number(pair[this.props.axes[1]])));
            },
            { fireImmediately: true }
        );
    };

    // anything that doesn't need to be recalculated should just be stored as drawCharts (i.e. computed values) and drawChart is gonna iterate over these observables and generate svgs based on that

    clearAnnotations = () => {
        const elements = document.querySelectorAll('.datapoint');
        for (let i = 0; i < elements.length; i++) {
            const element = elements[i];
            element.classList.remove('brushed');
            element.classList.remove('selected');
        }
    };
    // gets called whenever the "data-annotations" fields gets updated
    drawAnnotations = (dataX: number, dataY: number, selected?: boolean) => {
        // TODO: nda - can optimize this by having some sort of mapping of the x and y values to the individual circle elements
        // loop through all html elements with class .circle-d1 and find the one that has "data-x" and "data-y" attributes that match the dataX and dataY
        // if it exists, then highlight it
        // if it doesn't exist, then remove the highlight
        const elements = document.querySelectorAll('.datapoint');
        for (let i = 0; i < elements.length; i++) {
            const element = elements[i];
            const x = element.getAttribute('data-x');
            const y = element.getAttribute('data-y');
            if (x === dataX.toString() && y === dataY.toString()) {
                element.classList.add(selected ? 'selected' : 'brushed');
            }
            // TODO: nda - this remove highlight code should go where we remove the links
            // } else {
            // }
        }
    };

    removeAnnotations(dataX: number, dataY: number) {
        // loop through and remove any annotations that no longer exist
    }

    @action
    restoreView = (data: Doc) => {
        const coords = Cast(data.presDataVizSelection, listSpec('number'), null);
        if (coords?.length > 1 && (this._currSelected?.x !== coords[0] || this._currSelected?.y !== coords[1])) {
            this.setCurrSelected(coords[0], coords[1]);
            return true;
        }
        if (this._currSelected) {
            this.setCurrSelected();
            return true;
        }
        return false;
    };

    // create a document anchor that stores whatever is needed to reconstruct the viewing state (selection,zoom,etc)
    getAnchor = (pinProps?: PinProps) => {
        const anchor = Docs.Create.TextanchorDocument({ title: 'line doc selection' + this._currSelected?.x, unrendered: true });
        PresBox.pinDocView(anchor, { pinDocLayout: pinProps?.pinDocLayout, pinData: pinProps?.pinData }, this.props.dataDoc);
        anchor.presDataVizSelection = this._currSelected ? new List<number>([this._currSelected.x, this._currSelected.y]) : undefined;
        return anchor;
    };

    @computed get height() {
        return this.props.height - this.props.margin.top - this.props.margin.bottom;
    }

    @computed get width() {
        return this.props.width - this.props.margin.left - this.props.margin.right;
    }

    setupTooltip() {
        return d3
            .select(this._lineChartRef.current)
            .append('div')
            .attr('class', 'tooltip')
            .style('opacity', 0)
            .style('background', '#fff')
            .style('border', '1px solid #ccc')
            .style('padding', '5px')
            .style('position', 'absolute')
            .style('font-size', '12px');
    }

    // TODO: nda - use this everyewhere we update currSelected?
    @action
    setCurrSelected(x?: number, y?: number) {
        // TODO: nda - get rid of svg element in the list?
        this._currSelected = x !== undefined && y !== undefined ? { x, y } : undefined;
        this.props.pairs.forEach(pair => pair[this.props.axes[0]] === x && pair[this.props.axes[1]] === y && (pair.selected = true));
        this.props.pairs.forEach(pair => (pair.selected = pair[this.props.axes[0]] === x && pair[this.props.axes[1]] === y ? true : undefined));
    }

    drawDataPoints(data: DataPoint[], idx: number, xScale: d3.ScaleLinear<number, number, never>, yScale: d3.ScaleLinear<number, number, never>) {
        if (this._lineChartSvg) {
            const circleClass = '.circle-' + idx;
            this._lineChartSvg
                .selectAll(circleClass)
                .data(data)
                .join('circle') // enter append
                .attr('class', `${circleClass} datapoint`)
                .attr('r', '3') // radius
                .attr('cx', d => xScale(d.x))
                .attr('cy', d => yScale(d.y))
                .attr('data-x', d => d.x)
                .attr('data-y', d => d.y);
        }
    }

    // TODO: nda - can use d3.create() to create html element instead of appending
    drawChart = (dataSet: DataPoint[][], rangeVals: { xMin?: number; xMax?: number; yMin?: number; yMax?: number }, width: number, height: number) => {
        // clearing tooltip and the current chart
        d3.select(this._lineChartRef.current).select('svg').remove();
        d3.select(this._lineChartRef.current).select('.tooltip').remove();

        const { xMin, xMax, yMin, yMax } = rangeVals;
        if (xMin === undefined || xMax === undefined || yMin === undefined || yMax === undefined) {
            return;
        }

        // creating the x and y scales
        const xScale = scaleCreatorNumerical(xMin, xMax, 0, width);
        const yScale = scaleCreatorNumerical(0, yMax,height, 0);

        // adding svg
        const margin = this.props.margin;
        const svg = (this._lineChartSvg = d3
            .select(this._lineChartRef.current)
            .append('svg')
            .attr('width', `${width +margin.left + margin.right}`)
            .attr('height', `${height + margin.top + margin.bottom }`)
            .append('g')
            .attr('transform', `translate(${margin.left}, ${margin.top})`));

        // create x and y grids
        xGrid(svg.append('g'), height, xScale);
        yGrid(svg.append('g'), width, yScale);
        xAxisCreator(svg.append('g'), height, xScale);
        yAxisCreator(svg.append('g'), width, yScale);

        // draw the plot line
        const data = dataSet[0];
        const lineGen = createLineGenerator(xScale, yScale);
        drawLine(svg.append('path'), data, lineGen);

        // draw the datapoint circle
        this.drawDataPoints(data, 0, xScale, yScale);

        const higlightFocusPt = svg.append('g').style('display', 'none');
        higlightFocusPt.append('circle').attr('r', 5).attr('class', 'circle');
        const tooltip = this.setupTooltip();
        // add all the tooltipContent to the tooltip
        const mousemove = action((e: any) => {
            const bisect = d3.bisector((d: DataPoint) => d.x).left;
            const xPos = d3.pointer(e)[0];
            const x0 = Math.min(data.length - 1, bisect(data, xScale.invert(xPos - 5))); // shift x by -5 so that you can reach points on the left-side axis
            const d0 = data[x0];
            if (!d0) return;

            this.updateTooltip(higlightFocusPt, xScale, d0, yScale, tooltip);
        });

        const onPointClick = action((e: any) => {
            const bisect = d3.bisector((d: DataPoint) => d.x).left;
            const xPos = d3.pointer(e)[0];
            const x0 = bisect(data, xScale.invert(xPos - 5)); // shift x by -5 so that you can reach points on the left-side axis
            const d0 = data[x0];
            // find .circle-d1 with data-x = d0.x and data-y = d0.y
            const selected = svg.selectAll('.datapoint').filter((d: any) => d['data-x'] === d0.x && d['data-y'] === d0.y);
            this.setCurrSelected(d0.x, d0.y);
            this.updateTooltip(higlightFocusPt, xScale, d0, yScale, tooltip);
        });

        svg.append('rect')
            .attr('class', 'overlay')
            .attr('width', width)
            .attr('height', this.height + margin.top + margin.bottom)
            .attr('fill', 'none')
            .attr('translate', `translate(${margin.left}, ${-(margin.top + margin.bottom)})`)
            .style('opacity', 0)
            .on('mouseover', () => higlightFocusPt.style('display', null))
            .on('mouseout', () => tooltip.transition().duration(300).style('opacity', 0))
            .on('mousemove', mousemove)
            .on('click', onPointClick);
    };

    private updateTooltip(
        higlightFocusPt: d3.Selection<SVGGElement, unknown, null, undefined>,
        xScale: d3.ScaleLinear<number, number, never>,
        d0: DataPoint,
        yScale: d3.ScaleLinear<number, number, never>,
        tooltip: d3.Selection<HTMLDivElement, unknown, null, undefined>
    ) {
        higlightFocusPt.attr('transform', `translate(${xScale(d0.x)},${yScale(d0.y)})`).attr('class', this._currSelected?.x === d0.x && this._currSelected?.y === d0.y ? 'hoverHighlight-selected' : 'hoverHighlight');
        tooltip.transition().duration(300).style('opacity', 0.9);
        // TODO: nda - updating the inner html could be deadly cause injection attacks!
        tooltip
            .html(() => `<b>(${d0.x},${d0.y})</b>`) // text content for tooltip
            .style('pointer-events', 'none')
            .style('transform', `translate(${xScale(d0.x) - this.width / 2}px,${yScale(d0.y) - 30}px)`);
    }

    render() {
        const selectedPt = this._currSelected ? `x: ${this._currSelected.x} y: ${this._currSelected.y}` : 'none';
        return (
            <div ref={this._lineChartRef} className="chart-container">
                <span> {this.props.axes.length < 2 ? 'first use table view to select two axes to plot' : `Selected: ${selectedPt}`}</span>
            </div>
        );
    }
}