Input helper for Computer Futures worksheets - to be used with a browser extension like cjs (Custom JavaScript for websites)

cf-worksheets.js

/******************************************************************************************
* Input helper for Computer Futures worksheets
* - adds automatically missing zeros (9 -> 09:00)
* - computes total day working time and displays it also in human readable form (7.42 -> 7:25)
* - enables cursor navigation between input fields
* - removes all pre-filled entries from an empty worksheet
* (c) Oliver Becker, 2016-2018
******************************************************************************************/

(function() {

if (typeof(jQuery) === 'undefined') {
    return;
}

/* ************************************ jQuery Caret ************************************

https://github.com/accursoft/caret

Original code by Gideon Sireling
Minor refactorings by Oliver Becker

Copyright (c) 2009, Gideon Sireling

All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following
      disclaimer in the documentation and/or other materials provided
      with the distribution.

    * Neither the name of Gideon Sireling nor the names of other
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

(function($) {
  $.fn.caret = function(pos) {
    var target = this[0];
    var range1, range2, bookmark;
	var isContentEditable = target && target.contentEditable === 'true';
    //get
    if (arguments.length === 0) {
      if (!target) {
          return this;
      }
      //HTML5
      if (window.getSelection) {
        //contenteditable
        if (isContentEditable) {
          target.focus();
          range1 = window.getSelection().getRangeAt(0),
          range2 = range1.cloneRange();
          range2.selectNodeContents(target);
          range2.setEnd(range1.endContainer, range1.endOffset);
          return range2.toString().length;
        }
        //textarea
        return target.selectionStart;
      }
      //IE<9
      if (document.selection) {
        target.focus();
        //contenteditable
        if (isContentEditable) {
            range1 = document.selection.createRange();
            range2 = document.body.createTextRange();
            range2.moveToElementText(target);
            range2.setEndPoint('EndToEnd', range1);
            return range2.text.length;
        }
        //textarea
        pos = 0;
        range = target.createTextRange();
        range2 = document.selection.createRange().duplicate();
        bookmark = range2.getBookmark();
        range.moveToBookmark(bookmark);
        while (range.moveStart('character', -1) !== 0) pos++;
        return pos;
      }
      // Addition for jsdom support
      if (target.selectionStart)
        return target.selectionStart;
      //not supported
      return 0;
    } else if (!target) return;
    //set
    if (pos == -1)
      pos = this[isContentEditable? 'text' : 'val']().length;
    //HTML5
    if (window.getSelection) {
      //contenteditable
      if (isContentEditable) {
        target.focus();
        window.getSelection().collapse(target.firstChild, pos);
      }
      //textarea
      else
        target.setSelectionRange(pos, pos);
    }
    //IE<9
    else if (document.body.createTextRange) {
      if (isContentEditable) {
        var range = document.body.createTextRange();
        range.moveToElementText(target);
        range.moveStart('character', pos);
        range.collapse(true);
        range.select();
      } else {
        range = target.createTextRange();
        range.move('character', pos);
        range.select();
      }
    }
    if (!isContentEditable)
      target.focus();
    return this;
  }
})(jQuery);

// ******************************** End of jQuery Caret ********************************

    
var timeFormat = /^([01][0-9]|2[0-3]):([0-5][0-9])$/;
var hoursOnly = /^[0-9]{1,2}$/;
var missingZero = /^[0-9]:.*$/;

function diffMinutes(from, to) {
    var diff = 0;
    var fromMatch = from && from.match(timeFormat);
    var toMatch = to && to.match(timeFormat);
    if (fromMatch && toMatch) {
        diff = parseInt(toMatch[1], 10) * 60 + 
            parseInt(toMatch[2], 10) - 
            parseInt(fromMatch[1], 10) * 60 - 
            parseInt(fromMatch[2], 10) ;
    }
    return diff;
}

function compute($row, changed) {
    var $inputs = $row.find('td input')
    var from0 = $inputs.eq(0).val();
    var to0 = $inputs.eq(1).val();
    var from1 = $inputs.eq(2).val();
    var to1 = $inputs.eq(3).val();
    
    var sum = diffMinutes(from0, to0) + diffMinutes(from1, to1);
    var $field = $row.find('td span').add($row.find('td').last()).last();
    $field.text(sum
            ? (changed ? (sum / 60).toFixed(2) : $field.text()) + 
                '\u00a0\u00a0\u00a0(' + Math.floor(sum / 60) + ':' + ('0' + sum % 60).slice(-2) + ')'
            : '')
    	.css('color', changed ? '#888' : '#000')
}

function navigate(input, rowDiff, colDiff) {
    var $tr = $(input).parents('tr');
    var $trpar = $tr.parent();
    var colIndex = $tr.find('td input').index(input) + colDiff;
    var rowIndex = $trpar.find('tr').index($tr) + rowDiff;
    if (colIndex >= 0 && rowIndex >= 0) {
        var pos = $(input).caret();
        $trpar.find('tr').eq(rowIndex).find('td input').eq(colIndex)
            .focus().caret(colDiff < 0 ? -1 : colDiff > 0 ? 0 : pos);
    }
    return false;
}

$('.sheet td input:text').change(function() {
    var $input = $(this);
    var v = $input.val();
    if (hoursOnly.test(v)) {
        v += ':00';
    }
    if (missingZero.test(v)) {
        v = '0' + v;
    }
    $input.toggleClass('red', v && !timeFormat.test(v)).val(v);
    compute($input.parents('tr'), true);
}).keydown(function(event) {
    var code = event.which;
    if (code === 38) { // arrow up
        return navigate(this, -1, 0);
    } else if (code === 40) { // arrow down
        return navigate(this, 1, 0);
    } else if (code === 37 && $(this).caret() === 0) { // arrow left, cursor on first position
        return navigate(this, 0, -1);
    } else if (code === 39 && $(this).caret() == $(this).val().length) { // arrow right, cursor last pos
        return navigate(this, 0, 1);
    }
});

var emptySheet = $('#cwsRight').length === 0;
$('.sheet tr').each(function() {
    var $inputs = $('td input:text', this);
    if (emptySheet) {
        $inputs.val('');
    } else if ($inputs.length > 0) {
        compute($(this), false);
    }
});

})();