function show_comment_form($bubble) {

    var children = $bubble.closest('tr.line').children('[id]');

    var line_td_id = children[children.length - 1].id;

    var $comment_div = _get_add_comment_div(line_td_id);

    var f_path = $bubble.closest('[data-f_path]').data('f_path');

    var parts = line_td_id.split('_');

    var line_no = parts[parts.length-1];

    comment_div_state($comment_div, f_path, line_no, true);

}

// return comment div for target_id - add it if it doesn't exist yet

function _get_add_comment_div(target_id) {

    var comments_box_id = 'comments-' + target_id;

    var $comments_box = $('#' + comments_box_id);

    if (!$comments_box.length) {

        var html = '<tr><td id="{0}" colspan="3" class="inline-comments"></td></tr>'.format(comments_box_id);

        $('#' + target_id).closest('tr').after(html);

        $comments_box = $('#' + comments_box_id);

    }

    return $comments_box;

}

// Set $comment_div state - showing or not showing form and Add button.

// An Add button is shown on non-empty forms when no form is shown.

function comment_div_state($comment_div, f_path, line_no, show_form_opt) {

    var show_form = show_form_opt !== undefined ? show_form_opt : !f_path && !line_no;

    var $forms = $comment_div.children('.comment-inline-form');

    var $buttonrow = $comment_div.children('.add-button-row');

    var $comments = $comment_div.children('.comment');

    $forms.remove();

    $buttonrow.remove();

    if (show_form) {

        _comment_div_append_form($comment_div, f_path, line_no);

    } else if ($comments.length) {

        _comment_div_append_add($comment_div, f_path, line_no);

    }

}

// append an Add button to $comment_div and hook it up to show form

function _comment_div_append_add($comment_div, f_path, line_no) {

    var addlabel = TRANSLATION_MAP['Add Another Comment'];

    var $add = $('<div class="add-button-row"><span class="btn btn-default btn-xs add-button">{0}</span></div>'.format(addlabel));

    $comment_div.append($add);

    $add.children('.add-button').click(function(e) {

        comment_div_state($comment_div, f_path, line_no, true);

    });

}

// append a comment form to $comment_div

function _comment_div_append_form($comment_div, f_path, line_no) {

    var $form_div = $('#comment-inline-form-template').children()

        .clone()

        .addClass('comment-inline-form');

    $comment_div.append($form_div);

    var $form = $comment_div.find("form");

    var $textarea = $form.find('textarea');

    var $mentions_container = $form.find('div.mentions-container');

    $form.submit(function(e) {

            'text': text,

            'f_path': f_path,

            'line': line_no,

            'changeset_status': review_status,

            'save_close': pr_close,

            'save_delete': pr_delete

        };

        var success = function(json_data) {

            if (pr_delete) {

                location = json_data['location'];

            } else {

                $comment_div.append(json_data['rendered_text']);

                comment_div_state($comment_div, f_path, line_no);

                linkInlineComments($('.firstlink'), $('.comment:first-child'));

                if ((review_status || pr_close) && !f_path && !line_no) {

                    // Page changed a lot - reload it after closing the submitted form

                    comment_div_state($comment_div, f_path, line_no, false);

                    location.reload(true);

                }

            }

        };

        ajaxPOST(AJAX_COMMENT_URL, postData, success);

    });

    $form.find('.hide-inline-form').click(function(e) {

        comment_div_state($comment_div, f_path, line_no);

    });

    tooltip_activate();

    if ($textarea.length > 0) {

        MentionsAutoComplete($textarea, $mentions_container, _USERS_AC_DATA);

    }

    if (f_path) {

        $textarea.focus();

    }

}

function deleteComment(comment_id) {

    var url = AJAX_COMMENT_DELETE_URL.replace('__COMMENT_ID__', comment_id);

    var postData = {};

    var success = function(o) {

        $('#comment-'+comment_id).remove();

        // Ignore that this might leave a stray Add button (or have a pending form with another comment) ...

    }

    ajaxPOST(url, postData, success);

}