// Based on ng2-tooltip
// https://www.npmjs.com/package/ng2-tooltip

import { Component, Input, AfterViewInit, ElementRef, ChangeDetectorRef } from '@angular/core';

/**
 * En komponent för att visa content i tooltip.
 */
// Todo importera styles enligt wiki /vile
@Component({
    selector: 'fb-tooltip-content',
    templateUrl: './fbTooltip.component.html'
})
export class FbTooltipComponent implements AfterViewInit {
    @Input()
    hostElement: HTMLElement;
    @Input()
    fbTooltip: string;
    @Input()
    placement: 'top' | 'bottom' | 'left' | 'right' = 'top';
    @Input()
    animation: boolean = true;

    top: number;
    left: number;
    isIn: boolean = false;
    isFade: boolean = false;

    private readonly minimumNum: number = -100000;

    constructor(
        public element: ElementRef,
        private readonly cdr: ChangeDetectorRef
    ) {
        if (this.top === null || this.top === undefined) {
            this.top = this.minimumNum;
        }
        if (this.left === null || this.left === undefined) {
            this.left = this.minimumNum;
        }
    }

    ngAfterViewInit(): void {
        this.show();
        this.cdr.detectChanges();
    }

    show(): void {
        if (!this.hostElement) {
            return;
        }

        const p: {top: number, left: number} = this.positionElements(this.hostElement, this.element.nativeElement.children[0], this.placement);
        this.top = p.top;
        this.left = p.left;
        this.isIn = true;
        if (this.animation) {
            this.isFade = true;
        }
    }

    hide(): void {
        this.top = this.minimumNum;
        this.left = this.minimumNum;
        this.isIn = true;
        if (this.animation) {
            this.isFade = false;
        }
    }

    private positionElements(hostEl: HTMLElement,
        targetEl: HTMLElement,
        positionStr: string,
        appendToBody: boolean = false): { top: number, left: number } {
        const positionStrParts: string[] = positionStr.split('-');
        const pos0: string = positionStrParts[0];
        const pos1: string = positionStrParts[1] || 'center';
        const hostElPos: {width: number, height: number, top: number, left: number} = appendToBody ? this.offset(hostEl) : this.position(hostEl);
        const targetElWidth: number = targetEl.offsetWidth;
        const targetElHeight: number = targetEl.offsetHeight;

        const two: number = 2;
        const shiftWidth: any = {
            center: (): number => hostElPos.left + hostElPos.width / two - targetElWidth / two,
            left: (): number => hostElPos.left,
            right: (): number => hostElPos.left + hostElPos.width
        };

        const shiftHeight: any = {
            center: (): number => hostElPos.top + hostElPos.height / two - targetElHeight / two,
            top: (): number => hostElPos.top,
            bottom: (): number => hostElPos.top + hostElPos.height
        };

        let targetElPos: { top: number, left: number };
        switch (pos0) {
        case 'right':
            targetElPos = {
                top: shiftHeight[pos1](),
                left: shiftWidth[pos0]()
            };
            break;

        case 'left':
            targetElPos = {
                top: shiftHeight[pos1](),
                left: hostElPos.left - targetElWidth
            };
            break;

        case 'bottom':
            targetElPos = {
                top: shiftHeight[pos0](),
                left: shiftWidth[pos1]()
            };
            break;

        default:
            targetElPos = {
                top: hostElPos.top - targetElHeight,
                left: shiftWidth[pos1]()
            };
            break;
        }

        return targetElPos;
    }

    private position(nativeEl: HTMLElement): { width: number, height: number, top: number, left: number } {
        let offsetParentBcr: {top: number, left: number} = { top: 0, left: 0 };
        const elBcr: {width: number, height: number, top: number, left: number} = this.offset(nativeEl);
        const offsetParentEl: any = this.parentOffsetEl(nativeEl);
        if (offsetParentEl !== window.document) {
            offsetParentBcr = this.offset(offsetParentEl);
            offsetParentBcr.top += offsetParentEl.clientTop - offsetParentEl.scrollTop;
            offsetParentBcr.left += offsetParentEl.clientLeft - offsetParentEl.scrollLeft;
        }

        const boundingClientRect: ClientRect = nativeEl.getBoundingClientRect();
        return {
            width: boundingClientRect.width || nativeEl.offsetWidth,
            height: boundingClientRect.height || nativeEl.offsetHeight,
            top: elBcr.top - offsetParentBcr.top,
            left: elBcr.left - offsetParentBcr.left
        };
    }

    private offset(nativeEl: any): { width: number, height: number, top: number, left: number } {
        const boundingClientRect: any = nativeEl.getBoundingClientRect();
        return {
            width: boundingClientRect.width || nativeEl.offsetWidth,
            height: boundingClientRect.height || nativeEl.offsetHeight,
            top: boundingClientRect.top + (window.pageYOffset || window.document.documentElement.scrollTop),
            left: boundingClientRect.left + (window.pageXOffset || window.document.documentElement.scrollLeft)
        };
    }

    private getStyle(nativeEl: HTMLElement, cssProp: string): string {
        if ((nativeEl as any).currentStyle) { // IE
            return (nativeEl as any).currentStyle[cssProp];
        }

        if (window.getComputedStyle) {
            return (window.getComputedStyle(nativeEl) as any)[cssProp];
        }

        // finally try and get inline style
        return (nativeEl.style as any)[cssProp];
    }

    private isStaticPositioned(nativeEl: HTMLElement): boolean {
        return (this.getStyle(nativeEl, 'position') || 'static') === 'static';
    }

    private parentOffsetEl(nativeEl: HTMLElement): any {
        let offsetParent: any = nativeEl.offsetParent || window.document;
        while (offsetParent && offsetParent !== window.document && this.isStaticPositioned(offsetParent)) {
            offsetParent = offsetParent.offsetParent;
        }
        return offsetParent || window.document;
    }

}