iwmlib/lib/card/wrapper.js

/* eslint-disable no-console */
/* global TweenLite */

import Events from '../events.js'
import { Points } from '../utils.js'

export default class CardWrapper extends Object {
    constructor(
        domNode,
        { triggerSVGClicks = true, allowClickDistance = 44 } = {}
    ) {
        super()
        this.domNode = domNode
        this.triggerSVGClicks = triggerSVGClicks
        this.allowClickDistance = allowClickDistance
        this.tapNodes = new Map()
        this.tapHandler = new Map()
    }

    handleClicks() {
        this.domNode.addEventListener(
            'click',
            event => {
                if (event.isTrusted) {
                    Events.stop(event)
                    if (this.triggerSVGClicks && this.isSVGNode(event.target)) {
                        this.tap(event, 'triggerSVGClicks')
                    }
                }
            },
            true
        )
    }

    handleClicksAsTaps() {
        this.domNode.addEventListener(
            'click',
            event => {
                if (event.isTrusted) {
                    Events.stop(event)
                }
                this.tap(event)
            },
            true
        )
    }

    isClickable(node) {
        if (node == null) return false
        if (node.tagName == 'A' && node.hasAttribute('href')) return true
        if (node.hasAttribute('onclick')) return true
        return false
    }

    hasClickHandler(node) {
        if (node == null) return false
        if (this.tapNodes.has(node)) return true
        for (let [selector, handler] of this.tapHandler.entries()) {
            for (let obj of this.domNode.querySelectorAll(selector)) {
                if (node == obj) {
                    return true
                }
            }
        }
        return false
    }

    /**
     * Returns an array of all active nodes.
     * Unfortunately we cannot search for all nodes with an attached 'click' event listener
     * See https://stackoverflow.com/questions/11455515/how-to-check-whether-dynamically-attached-event-listener-exists-or-not
     * Therefore we can only detect the following standard cases:
     * I. All clickable objects like activeNodes
     * II. Objects that have been attached a click handler by the scatter itself via
     */
    activeNodes() {
        let result = []
        for (let node of this.domNode.querySelectorAll('*')) {
            if (this.isClickable(node)) result.push(node)
            if (this.hasClickHandler(node)) result.push(node)
        }
        return result
    }

    nearestActive(event) {
        let element = this.domNode
        let activeNodes = this.activeNodes()
        let globalClick = event.center
            ? event.center
            : { x: event.x, y: event.y }
        let localClick = Points.fromPageToNode(element, globalClick)

        let clickRects = activeNodes.map(link => {
            let rect = link.getBoundingClientRect()
            let topLeft = Points.fromPageToNode(element, rect)
            let center = Points.fromPageToNode(element, {
                x: rect.x + rect.width / 2,
                y: rect.y + rect.height / 2
            })
            return {
                x: topLeft.x,
                y: topLeft.y,
                width: rect.width,
                height: rect.height,
                center,
                link
            }
        })

        let distances = []
        clickRects.forEach(rect => {
            let distance = Points.distanceToRect(localClick, rect)
            distances.push(parseInt(distance))
        })

        let closestClickIndex = distances.indexOf(Math.min(...distances))
        let closestClickable = activeNodes[closestClickIndex]
        if (distances[closestClickIndex] < this.allowClickDistance) {
            return closestClickable
        }
        return null
    }

    isSVGNode(node) {
        return node.ownerSVGElement || node.tagName == 'svg'
    }

    simulateClick(node, event) {
        /* https://stackoverflow.com/questions/49564905/is-it-possible-to-use-click-function-on-svg-tags-i-tried-element-click-on-a
         proposes the dispatchEvent solution. But this leads to problems in flippable.html hiding the back page.
        Therefore we use the original click event (see constructor). */
        if (this.isSVGNode(node)) {
            if (this.triggerSVGClicks) {
                let click = new Event('click')
                node.dispatchEvent(click)
            }
            return
        }
        node.click()
    }

    nodeTapped(node, event) {
        if (this.isClickable(node)) {
            this.simulateClick(node, event)
            return true
        }
        if (this.tapNodes.has(node)) {
            handler = this.tapNodes.get(node)
            handler(event)
            return true
        }
        for (let [selector, handler] of this.tapHandler.entries()) {
            for (let obj of this.domNode.querySelectorAll(selector)) {
                if (node == obj) {
                    handler(event)
                    return true
                }
            }
        }
        return false
    }

    tap(event, calledBy = 'unknown') {
        if (event.isTrusted) {
            let node = this.nearestActive(event)
            this.nodeTapped(node, event)

            /*  let node = document.elementFromPoint(event.clientX, event.clientY)
            if (!this.nodeTapped(node, event)) {
                node = this.nearestActive(event)
                this.nodeTapped(node, event)
            } */
        }
    }

    onTap(objOrSelector, handler) {
        if (typeof objOrSelector == 'string') {
            this.tapHandler.set(objOrSelector, handler)
        } else {
            this.tapNodes.set(objOrSelector, handler)
        }
    }
}