uktrade/lite-forms

{% load static %}

<div class="app-markdown">
    <div id="format-bar-{{ name }}" class="app-markdown__format-bar">
        <button id="button-format-bold" type="button" name="button" class="app-markdown__format-bar__button">B<span class="govuk-visually-hidden">old</span></button>
        <button id="button-format-italic" type="button" name="button" class="app-markdown__format-bar__button">I<span class="govuk-visually-hidden">talic</span></button>
    </div>
    <div data-module="character-count" data-maxlength="{{ extras.max_length }}">
        <textarea class="app-markdown__textarea js-character-count {% if error %}govuk-textarea--error{% endif %}"
              id="{{ name }}"
              name="{{ name }}"
              rows="10"
              cols="40"
              {% if extras.max_length %}
                  maxlength="{{ extras.max_length }}"
              {% endif %}>{{ value }}</textarea>
        {% if extras.max_length %}
            <span id="{{ name }}-info" class="govuk-hint govuk-character-count__message" aria-live="polite">
                You can enter up to {{ extras.max_length }} characters
            </span>
        {% endif %}
    </div>
</div>

{% block javascript %}
    <script type="text/javascript" src="{% static 'javascripts/highlight-tags.js' %}"></script>

    <script type="text/javascript">
        $('#{{ name }}').highlightWithinTextarea({
            highlight: [
                {
                    highlight: {% verbatim %}/{{(.*?)}}/g{% endverbatim %},
                    className: 'lite-highlight'
                },
                {
                    highlight: {% verbatim %}/{%(.*?)%}/g{% endverbatim %},
                    className: 'lite-highlight lite-highlight--purple'
                }
            ]
        });
    </script>

    <script type="text/javascript">
        function getInputSelection(el) {
            var start = 0, end = 0, normalizedValue, range,
                textInputRange, len, endRange;

            if (typeof el.selectionStart == "number" && typeof el.selectionEnd == "number") {
                start = el.selectionStart;
                end = el.selectionEnd;
            } else {
                range = document.selection.createRange();

                if (range && range.parentElement() == el) {
                    len = el.value.length;
                    normalizedValue = el.value.replace(/\r\n/g, "\n");

                    // Create a working TextRange that lives only in the input
                    textInputRange = el.createTextRange();
                    textInputRange.moveToBookmark(range.getBookmark());

                    // Check if the start and end of the selection are at the very end
                    // of the input, since moveStart/moveEnd doesn't return what we want
                    // in those cases
                    endRange = el.createTextRange();
                    endRange.collapse(false);

                    if (textInputRange.compareEndPoints("StartToEnd", endRange) > -1) {
                        start = end = len;
                    } else {
                        start = -textInputRange.moveStart("character", -len);
                        start += normalizedValue.slice(0, start).split("\n").length - 1;

                        if (textInputRange.compareEndPoints("EndToEnd", endRange) > -1) {
                            end = len;
                        } else {
                            end = -textInputRange.moveEnd("character", -len);
                            end += normalizedValue.slice(0, end).split("\n").length - 1;
                        }
                    }
                }
            }

            return {
                start: start,
                end: end
            };
        }

        function replaceSelectedText(modifier) {
            var element = document.getElementById("{{ name }}")
            var selectedIndex = getInputSelection(element);
            var selectedText = element.value.substring(selectedIndex.start, selectedIndex.end);
            var val = element.value;

            if (selectedText.startsWith(modifier) && selectedText.endsWith(modifier)) {
                newText = selectedText.substring(modifier.length, selectedText.length - modifier.length);
                element.value = val.slice(0, selectedIndex.start) + newText + val.slice(selectedIndex.end);
                element.setSelectionRange(selectedIndex.start, selectedIndex.end - (modifier.length * 2))
            } else {
                newText = modifier + selectedText + modifier;
                element.value = val.slice(0, selectedIndex.start) + newText + val.slice(selectedIndex.end);
                element.setSelectionRange(selectedIndex.start, selectedIndex.end + (modifier.length * 2))
            }
        }

        $("#button-format-bold").click(function() {
            replaceSelectedText("**");
        });

        $("#button-format-italic").click(function() {
            replaceSelectedText("_");
        });

        $('#{{ name }}').highlightWithinTextarea('update');
    </script>
{% endblock %}