blob: 8d2fc845115ac7b8f7ca88eefaa519f90e9a0f39 [file] [log] [blame]
// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
export function anyToString(x: any): string {
return "" + x;
}
function computeScrollTop(container, element) {
const height = container.offsetHeight;
const margin = Math.floor(height / 4);
const pos = element.offsetTop;
const currentScrollTop = container.scrollTop;
if (pos < currentScrollTop + margin) {
return Math.max(0, pos - margin);
} else if (pos > (currentScrollTop + 3 * margin)) {
return Math.max(0, pos - 3 * margin);
}
return pos;
}
export class ViewElements {
container: HTMLElement;
scrollTop: number;
constructor(container: HTMLElement) {
this.container = container;
this.scrollTop = undefined;
}
consider(element, doConsider) {
if (!doConsider) return;
const newScrollTop = computeScrollTop(this.container, element);
if (isNaN(newScrollTop)) {
console.log("NOO");
}
if (this.scrollTop === undefined) {
this.scrollTop = newScrollTop;
} else {
this.scrollTop = Math.min(this.scrollTop, newScrollTop);
}
}
apply(doApply) {
if (!doApply || this.scrollTop === undefined) return;
this.container.scrollTop = this.scrollTop;
}
}
export function sortUnique<T>(arr: Array<T>, f: (a: T, b: T) => number, equal: (a: T, b: T) => boolean) {
if (arr.length == 0) return arr;
arr = arr.sort(f);
const ret = [arr[0]];
for (let i = 1; i < arr.length; i++) {
if (!equal(arr[i - 1], arr[i])) {
ret.push(arr[i]);
}
}
return ret;
}
// Partial application without binding the receiver
export function partial(f: any, ...arguments1: Array<any>) {
return function (this: any, ...arguments2: Array<any>) {
f.apply(this, [...arguments1, ...arguments2]);
};
}
export function isIterable(obj: any): obj is Iterable<any> {
return obj != null && obj != undefined
&& typeof obj != 'string' && typeof obj[Symbol.iterator] === 'function';
}
export function alignUp(raw: number, multiple: number): number {
return Math.floor((raw + multiple - 1) / multiple) * multiple;
}
export function measureText(text: string) {
const textMeasure = document.getElementById('text-measure');
if (textMeasure instanceof SVGTSpanElement) {
textMeasure.textContent = text;
return {
width: textMeasure.getBBox().width,
height: textMeasure.getBBox().height,
};
}
return { width: 0, height: 0 };
}
// Interpolate between the given start and end values by a fraction of val/max.
export function interpolate(val: number, max: number, start: number, end: number) {
return start + (end - start) * (val / max);
}
export function createElement(tag: string, cls: string, content?: string) {
const el = document.createElement(tag);
el.className = cls;
if (content != undefined) el.innerText = content;
return el;
}