shortcut.js

/**
 * www.openjs.com/scripts/events/keyboard_shortcuts/
 * Version : 2.01.B
 * By Binny V A
 * License : BSD
 */
"use strict";
export default {
  all_shortcuts: {}, //All the shortcuts are stored in this array
  add: function(shortcut_combination, callback, opt) {
    //Provide a set of default options
    var default_options = {
      type: "keydown",
      propagate: false,
      disable_in_input: false,
      target: document,
      keycode: false,
    };
    if (!opt) {
      opt = default_options;
    } else {
      for (var dfo in default_options) {
        if (typeof opt[dfo] == "undefined") opt[dfo] = default_options[dfo];
      }
    }

    var ele = opt.target;
    if (typeof opt.target == "string")
      ele = document.getElementById(opt.target);
    var ths = this;
    shortcut_combination = shortcut_combination.toLowerCase();

    //The function to be called at keypress
    var func = function(e) {
      var code;
      e = e || window.event;

      if (opt["disable_in_input"]) {
        //Don't enable shortcut keys in Input, Textarea fields
        var element;
        if (e.target) element = e.target;
        else if (e.srcElement) element = e.srcElement;
        if (element.nodeType == 3) element = element.parentNode;

        if (element.tagName == "INPUT" || element.tagName == "TEXTAREA") return;
      }

      //Find Which key is pressed
      if (e.keyCode) code = e.keyCode;
      else if (e.which) code = e.which;
      var character = String.fromCharCode(code).toLowerCase();

      if (code == 188) character = ","; //If the user presses , when the type is onkeydown
      if (code == 190) character = "."; //If the user presses , when the type is onkeydown

      var keys = shortcut_combination.split("+");
      //Key Pressed - counts the number of valid keypresses - if it is same as the number of keys, the shortcut function is invoked
      var kp = 0;

      //Work around for stupid Shift key bug created by using lowercase - as a result the shift+num combination was broken
      var shift_nums = {
        "`": "~",
        "1": "!",
        "2": "@",
        "3": "#",
        "4": "$",
        "5": "%",
        "6": "^",
        "7": "&",
        "8": "*",
        "9": "(",
        "0": ")",
        "-": "_",
        "=": "+",
        ";": ":",
        "'": '"',
        ",": "<",
        ".": ">",
        "/": "?",
        "\\": "|",
      };
      //Special Keys - and their codes
      var special_keys = {
        esc: 27,
        escape: 27,
        tab: 9,
        space: 32,
        return: 13,
        enter: 13,
        backspace: 8,

        scrolllock: 145,
        scroll_lock: 145,
        scroll: 145,
        capslock: 20,
        caps_lock: 20,
        caps: 20,
        numlock: 144,
        num_lock: 144,
        num: 144,

        pause: 19,
        break: 19,

        insert: 45,
        home: 36,
        delete: 46,
        end: 35,

        pageup: 33,
        page_up: 33,
        pu: 33,

        pagedown: 34,
        page_down: 34,
        pd: 34,

        left: 37,
        up: 38,
        right: 39,
        down: 40,

        f1: 112,
        f2: 113,
        f3: 114,
        f4: 115,
        f5: 116,
        f6: 117,
        f7: 118,
        f8: 119,
        f9: 120,
        f10: 121,
        f11: 122,
        f12: 123,
      };

      var modifiers = {
        shift: { wanted: false, pressed: false },
        ctrl: { wanted: false, pressed: false },
        alt: { wanted: false, pressed: false },
        meta: { wanted: false, pressed: false }, //Meta is Mac specific
      };

      if (e.ctrlKey) modifiers.ctrl.pressed = true;
      if (e.shiftKey) modifiers.shift.pressed = true;
      if (e.altKey) modifiers.alt.pressed = true;
      if (e.metaKey) modifiers.meta.pressed = true;

      for (var i = 0, k; (k = keys[i]), i < keys.length; i++) {
        //Modifiers
        if (k == "ctrl" || k == "control") {
          kp++;
          modifiers.ctrl.wanted = true;
        } else if (k == "shift") {
          kp++;
          modifiers.shift.wanted = true;
        } else if (k == "alt") {
          kp++;
          modifiers.alt.wanted = true;
        } else if (k == "meta") {
          kp++;
          modifiers.meta.wanted = true;
        } else if (k.length > 1) {
          //If it is a special key
          if (special_keys[k] == code) kp++;
        } else if (opt["keycode"]) {
          if (opt["keycode"] == code) kp++;
        } else {
          //The special keys did not match
          if (character == k) kp++;
          else {
            if (shift_nums[character] && e.shiftKey) {
              //Stupid Shift key bug created by using lowercase
              character = shift_nums[character];
              if (character == k) kp++;
            }
          }
        }
      }

      if (
        kp == keys.length &&
        modifiers.ctrl.pressed == modifiers.ctrl.wanted &&
        modifiers.shift.pressed == modifiers.shift.wanted &&
        modifiers.alt.pressed == modifiers.alt.wanted &&
        modifiers.meta.pressed == modifiers.meta.wanted
      ) {
        callback(e);

        if (!opt["propagate"]) {
          //Stop the event
          //e.cancelBubble is supported by IE - this will kill the bubbling process.
          e.cancelBubble = true;
          e.returnValue = false;

          //e.stopPropagation works in Firefox.
          if (e.stopPropagation) {
            e.stopPropagation();
            e.preventDefault();
          }
          return false;
        }
      }
    };
    this.all_shortcuts[shortcut_combination] = {
      callback: func,
      target: ele,
      event: opt["type"],
    };
    //Attach the function with the event
    if (ele.addEventListener) ele.addEventListener(opt["type"], func, false);
    else if (ele.attachEvent) ele.attachEvent("on" + opt["type"], func);
    else ele["on" + opt["type"]] = func;
  },

  //Remove the shortcut - just specify the shortcut and I will remove the binding
  // 'remove':function(shortcut_combination) {
  //  shortcut_combination = shortcut_combination.toLowerCase();
  //  var binding = this.all_shortcuts[shortcut_combination];
  //  delete(this.all_shortcuts[shortcut_combination])
  //  if(!binding) return;
  //  var type = binding['event'];
  //  var ele = binding['target'];
  //  var callback = binding['callback'];
  //
  //  if(ele.detachEvent) ele.detachEvent('on'+type, callback);
  //  else if(ele.removeEventListener) ele.removeEventListener(type, callback, false);
  //  else ele['on'+type] = false;
  // }
};