@import "mediawiki.mixins";
@import "mediawiki.ui/variables";

// Checkbox
//
// Styling checkboxes in a way that works cross browser is a tricky problem to solve.
// In MediaWiki UI put a checkbox and label inside a mw-ui-checkbox div.
// This renders in all browsers except IE6-8 which do not support the :checked selector;
// these are kept backwards-compatible using the :not(#noop) selector.
// You should give the checkbox and label matching "id" and "for" attributes, respectively.
//
// Markup:
// <div class="mw-ui-checkbox">
//   <input type="checkbox" id="kss-example-5"><label for="kss-example-5">Standard checkbox</label>
// </div>
// <div class="mw-ui-checkbox">
//   <input type="checkbox" id="kss-example-5-checked" checked><label for="kss-example-5-checked">Standard checked checkbox</label>
// </div>
// <div class="mw-ui-checkbox">
//   <input type="checkbox" id="kss-example-5-disabled" disabled><label for="kss-example-5-disabled">Disabled checkbox</label>
// </div>
// <div class="mw-ui-checkbox">
//   <input type="checkbox" id="kss-example-5-disabled-checked" disabled checked><label for="kss-example-5-disabled-checked">Disabled checked checkbox</label>
// </div>
//
// Styleguide 5.
.mw-ui-checkbox {
	display: inline-block;
	vertical-align: middle;
}

@checkboxSize: 1.6em;

// We use the not selector to cancel out styling on IE 8 and below
.mw-ui-checkbox:not(#noop) {
	// Position relatively so we can make use of absolute pseudo elements
	position: relative;
	line-height: @checkboxSize;

	* {
		vertical-align: middle;
	}

	input[type="checkbox"] {
		// we hide the input element as instead we will style the label that follows
		// we use opacity so that VoiceOver software can still identify it
		opacity: 0;
		// ensure the invisible checkbox takes up the required width
		width: @checkboxSize;
		height: @checkboxSize;
		// This is needed for Firefox mobile (See bug 71750 to workaround default Firefox stylesheet)
		max-width: none;
		margin-right: .4em;

		// the pseudo before element of the label after the checkbox now looks like a checkbox
		& + label {
			cursor: pointer;

			&::before {
				content: '';
				position: absolute;
				left: 0;
				border-radius: @borderRadius;
				width: @checkboxSize;
				height: @checkboxSize;
				background-color: #fff;
				border: 1px solid grey;
			}
		}

		// when the input is checked, style the label pseudo before element that followed as a checked checkbox
		&:checked {
			+ label {
				&::before {
					.background-image-svg('images/checked.svg', 'images/checked.png');
					.background-size( @checkboxSize, @checkboxSize );
					background-repeat: no-repeat;
					background-position: center top;
				}
			}
		}

		@focusBottomBorderSize: 0.2em;
		&:active,
		&:focus {
			+ label {
				&::before {
					box-shadow: inset 0 -@focusBottomBorderSize 0 0 lightgrey;
				}
			}
		}

		// disabled checked boxes have a gray background
		&:disabled + label {
			cursor: default;

			&::before {
				background-color: lightgrey;
			}
		}
	}
}