/**
 * Created by mm28969 on 10/24/16.
 * modified by mm17060 on 6/12/17
 */


// declare let d3;
import * as d3 from "d3";

import {convertValueToAttribute, OrientationEnum} from "../mmviz-common/index";

import {Layout, createViewModel} from "./layout";
import {LayoutScale} from "./scale";

export function getBarDomain(dataArray, valueMap){
    // valueMap: a function to extract the value out of dataArray for d3.extent to determine the length of the bar
    let domain = d3.extent(dataArray, valueMap);

    // positive chart, set baseline at zero
    if(domain[0] > 0 && domain[1] > 0){
        domain = [0, d3.max(domain)];
    }
    // negative chart, set baseline at zero
    else if(domain[0] < 0 && domain[1] < 0){
        domain = [d3.min(domain), 0];
    }

    return domain;
}

/**
 *  return a bar layout creator which is a function that maps data to visual elements
 *  it is able to accept user defined base for the bar chart by providing `valueBaseMap` in dataModel, by default the
 *  bar starts at 0
 * @param {OrientationEnum} orientationEnum
 * @param {string} colorScaleKey
 * @returns a function which will calculate the viewModel (pixel) that is mapped from dataModel (actual data)
 * {(dataModel, layoutScale: LayoutScale) => () => {keyMap: (d) => any; dataArray: any[]}}
 */
export function barLayoutCreator(orientationEnum = OrientationEnum.VERTICAL, colorScaleKey = "color") {

    // layout extender
    return function(dataModel,layoutScale: LayoutScale){

        let xDomain, yDomain;
        if (OrientationEnum.VERTICAL === orientationEnum) {
            if ("valueBaseMap" in dataModel){
                // when providing customized bar base, need to consider y0 and y1 together to get the correct y domain
                const y0Domain = getBarDomain(dataModel.dataArray, dataModel.valueBaseMap),
                      y1Domain = getBarDomain(dataModel.dataArray,dataModel.valueMap);
                yDomain = d3.extent(y0Domain.concat(y1Domain));
            }
            else{
                // yDomain is calculated using the max y, which is y1, also called valueMap in dataModel
                yDomain = getBarDomain(dataModel.dataArray, dataModel.valueMap);
            }
            xDomain = dataModel.dataArray.map(dataModel.keyMap);
        }
        else if (OrientationEnum.HORIZONTAL === orientationEnum) {
            if ("valueBaseMap" in dataModel){
                const x0Domain = getBarDomain(dataModel.dataArray, dataModel.valueBaseMap),
                      x1Domain = getBarDomain(dataModel.dataArray, dataModel.valueMap);
                xDomain = d3.extent(x0Domain.concat(x1Domain));
            }
            else{
                xDomain = getBarDomain(dataModel.dataArray, dataModel.valueMap);
            }
            yDomain = dataModel.dataArray.map(dataModel.keyMap);
        }

        layoutScale.extendDomainX(xDomain).extendDomainY(yDomain);

        function layoutDatum(d){

            let key = dataModel.keyMap(d),
                value = dataModel.valueMap(d),
                color,
                dLayout: any = {}; //dlayout's y0 should be always smaller than y

            dLayout.key = key; // unique identifier for the bar
            dLayout.value = value; // y1 value, if the base is undefined, y1 value is the actual value of the bar
            dLayout.original = d; // keep the original data row
            // dlayout.color is an object with key and value
            color = layoutScale.mapValue(colorScaleKey, dataModel, d); // color is mapped using colorValueMap function from dataModel
            dLayout.color = color;
            dLayout.category = color.key;
            // The categoryAttr attribute is added to the html element as class, it can be used as a JavaScript or css selector.
            dLayout.categoryAttr = "category-" + convertValueToAttribute(color.key);

            if (OrientationEnum.VERTICAL === orientationEnum) {
                // (x0, y0) is where the entry point is, x=x0, y is used to calculate the height together with y0
                dLayout.x = layoutScale.xScale(key);
                dLayout.x0 = dLayout.x;
                if ("valueBaseMap" in dataModel){
                    dLayout.y0 = layoutScale.yScale(dataModel.valueBaseMap(d));
                }
                else{
                    dLayout.y0 = layoutScale.yScale(0); // the original zeroRange
                }
                dLayout.width = layoutScale.xScale.bandwidth();

                if(value >= 0) {
                    dLayout.height = (dLayout.y0 - layoutScale.yScale(value));
                    dLayout.y = layoutScale.yScale(value);
                }
                else {
                    dLayout.height = (layoutScale.yScale(value) - dLayout.y0);
                    dLayout.y = dLayout.y0;
                }
            }
            else if (OrientationEnum.HORIZONTAL === orientationEnum) {
                if ("valueBaseMap" in dataModel) {
                    dLayout.x0 = layoutScale.xScale(dataModel.valueBaseMap(d));
                }
                else{
                    dLayout.x0 = layoutScale.xScale(0);
                }
                dLayout.y = layoutScale.yScale(key);
                dLayout.y0 = dLayout.y;
                dLayout.height = layoutScale.yScale.bandwidth();

                if (value >= 0){
                    dLayout.x = dLayout.x0;
                    dLayout.width = (layoutScale.xScale(value) - dLayout.x0);
                }
                else {
                    dLayout.width = (dLayout.x0 - layoutScale.xScale(value));
                    dLayout.x = (dLayout.x0 - dLayout.width);
                }
            }

            return dLayout;
        }

        // layouter
        return function(){

            let d, dLayout,
                viewModel = createViewModel();

            for (d of dataModel.dataArray){
                dLayout = layoutDatum(d);

                if(dataModel.detailsMap){
                    dLayout.details = dataModel.detailsMap(d);
                }

                viewModel.dataArray.push(dLayout);
            }

            return viewModel;

        }

    }

}