gram: card

> ./src/utils.ts

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/** Try to extract the first integer from a text string or HTML element */
export function extractNumber(input: any, defaultValue?: number, commaIsDecimalSeparator: boolean = false): number {
  let text, result;

  if (input instanceof HTMLElement) {
    text = input.textContent
  } else if (typeof input === "string") {
    text = input
  }
  if (text) { result = text.match(/[^0-9]*([0-9\.\,]*).*/)[1] }
  if (result && !commaIsDecimalSeparator) {
    // in the US and elsewhere, commas are thousands separator so they can be removed.
    // in other countries, the commas is the decimal separator.
    result = result.replace(/,/g, '')
  }
  if (result) {
    return Number(result)
  } else if (defaultValue !== undefined) {
    return defaultValue
  } else {
    return null
  }
}

/** Returns true if current page URL contains given URL as substring.
 *  Mainly used in [[SiteAdapterOptions]] enable functions
*/
export function urlContains(fragment: string): boolean {
  return String(window.location).indexOf(fragment) !== -1
}

export function urlExact(url: string): boolean {
  return String(window.location) === url ||
    String(window.location) === "https://" + url
}

export function urlMatches(regex: RegExp): boolean {
  return regex.test(String(window.location));
}

export function htmlToElement(html): HTMLElement {
  var template = document.createElement('template');
  html = html.trim(); // Never return a text node of whitespace as the result
  template.innerHTML = html;
  return template.content.firstChild as HTMLElement;
}

export function onDomReady(fn) {
  if (document.readyState != 'loading') fn();
  else document.addEventListener('DOMContentLoaded', fn)
}

export function readFromChromeLocalStorage(keys) {
  return new Promise((resolve, reject) => {
    chrome.storage.local.get(keys, (results) => {
      resolve(results)
    });
  });
}

export function saveToChromeLocalStorage(entries) {
  return new Promise((resolve, reject) => {
    chrome.storage.local.set(entries);
    resolve();
  });
}

export function removeFromChromeLocalStorage(keys) {
  return new Promise((resolve, reject) => {
    chrome.storage.local.remove(keys);
    resolve();
  });
}

export function compileJavascript(code) {
  return eval(code);
}

export function throttleFunction(delay, fn) {
  let lastCall = 0;
  return function (...args) {
    const now = (new Date).getTime();
    if (now - lastCall < delay) {
      return;
    }
    lastCall = now;
    return fn(...args);
  }
}