https://lums.edu.pk/core/misc/dialog/dialog.position.js?v=10.2.12

1/**
2 * @file
3 * Positioning extensions for dialogs.
4 */
5
6/**
7 * Triggers when content inside a dialog changes.
8 *
9 * @event dialogContentResize
10 */
11
12(function ($, Drupal, drupalSettings, debounce, displace) {
13  // autoResize option will turn off resizable and draggable.
14  drupalSettings.dialog = $.extend(
15    { autoResize: true, maxHeight: '95%' },
16    drupalSettings.dialog,
17  );
18
19  /**
20   * Position the dialog's center at the center of displace.offsets boundaries.
21   *
22   * @function Drupal.dialog~resetPosition
23   *
24   * @param {object} options
25   *   Options object.
26   *
27   * @return {object}
28   *   Altered options object.
29   */
30  function resetPosition(options) {
31    const offsets = displace.offsets;
32    const left = offsets.left - offsets.right;
33    const top = offsets.top - offsets.bottom;
34
35    const leftString = `${
36      (left > 0 ? '+' : '-') + Math.abs(Math.round(left / 2))
37    }px`;
38    const topString = `${
39      (top > 0 ? '+' : '-') + Math.abs(Math.round(top / 2))
40    }px`;
41    options.position = {
42      my: `center${left !== 0 ? leftString : ''} center${
43        top !== 0 ? topString : ''
44      }`,
45      of: window,
46    };
47    return options;
48  }
49
50  /**
51   * Resets the current options for positioning.
52   *
53   * This is used as a window resize and scroll callback to reposition the
54   * jQuery UI dialog. Although not a built-in jQuery UI option, this can
55   * be disabled by setting autoResize: false in the options array when creating
56   * a new {@link Drupal.dialog}.
57   *
58   * @function Drupal.dialog~resetSize
59   *
60   * @param {jQuery.Event} event
61   *   The event triggered.
62   *
63   * @fires event:dialogContentResize
64   */
65  function resetSize(event) {
66    const positionOptions = [
67      'width',
68      'height',
69      'minWidth',
70      'minHeight',
71      'maxHeight',
72      'maxWidth',
73      'position',
74    ];
75    let adjustedOptions = {};
76    let windowHeight = $(window).height();
77    let option;
78    let optionValue;
79    let adjustedValue;
80    for (let n = 0; n < positionOptions.length; n++) {
81      option = positionOptions[n];
82      optionValue = event.data.settings[option];
83      if (optionValue) {
84        // jQuery UI does not support percentages on heights, convert to pixels.
85        if (
86          typeof optionValue === 'string' &&
87          /%$/.test(optionValue) &&
88          /height/i.test(option)
89        ) {
90          // Take offsets in account.
91          windowHeight -= displace.offsets.top + displace.offsets.bottom;
92          adjustedValue = parseInt(
93            0.01 * parseInt(optionValue, 10) * windowHeight,
94            10,
95          );
96          // Don't force the dialog to be bigger vertically than needed.
97          if (
98            option === 'height' &&
99            event.data.$element.parent().outerHeight() < adjustedValue
100          ) {
101            adjustedValue = 'auto';
102          }
103          adjustedOptions[option] = adjustedValue;
104        }
105      }
106    }
107    // Offset the dialog center to be at the center of Drupal.displace.offsets.
108    if (!event.data.settings.modal) {
109      adjustedOptions = resetPosition(adjustedOptions);
110    }
111    event.data.$element
112      .dialog('option', adjustedOptions)
113      .trigger('dialogContentResize');
114  }
115
116  $(window).on({
117    'dialog:aftercreate': function (event, dialog, $element, settings) {
118      const autoResize = debounce(resetSize, 20);
119      const eventData = { settings, $element };
120      if (settings.autoResize === true || settings.autoResize === 'true') {
121        const uiDialog = $element
122          .dialog('option', { resizable: false, draggable: false })
123          .dialog('widget');
124        uiDialog[0].style.position = 'fixed';
125        $(window)
126          .on('resize.dialogResize scroll.dialogResize', eventData, autoResize)
127          .trigger('resize.dialogResize');
128        $(document).on(
129          'drupalViewportOffsetChange.dialogResize',
130          eventData,
131          autoResize,
132        );
133      }
134    },
135    'dialog:beforeclose': function (event, dialog, $element) {
136      $(window).off('.dialogResize');
137      $(document).off('.dialogResize');
138    },
139  });
140})(jQuery, Drupal, drupalSettings, Drupal.debounce, Drupal.displace);