@use "../base";
@use "../colors";
@use "../functions" as *;

$bg-map: colors.$bg-map !default;
$fg-map: colors.$fg-map !default;
$ring-color: hsl(212.2, 46.8%, 60.2%) !default;
$knob-color: hsl(0, 0%, 20%) !default;
$popup-background-color: hsl(0, 0%, 0%) !default;
$popup-text-color: hsl(0, 0%, 100%) !default;

$inner-padding: 0.1em;

.Knob {
  position: relative;
  font-size: 1rem;
  width: 2.6em;
  height: 2.6em;
  margin: 0 auto;
  margin-bottom: -0.2em;
  cursor: n-resize;

  // Adjusts a baseline in a way, that makes knob middle-aligned
  // when it flows with the text.
  &:after {
    content: ".";
    color: transparent;
    line-height: 2.5em;
  }
}

.Knob__circle {
  position: absolute;
  top: $inner-padding;
  bottom: $inner-padding;
  left: $inner-padding;
  right: $inner-padding;
  margin: 0.3em;
  background-color: $knob-color;
  background-image: linear-gradient(
    to bottom,
    rgba(255, 255, 255, 0.15) 0%,
    rgba(255, 255, 255, 0) 100%
  );
  border-radius: 50%;
  box-shadow: 0 0.05em 0.5em 0 rgba(0, 0, 0, 0.5);
}

.Knob__cursorBox {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
}

.Knob__cursor {
  position: relative;
  top: 0.05em;
  margin: 0 auto;
  width: 0.2em;
  height: 0.8em;
  background-color: rgba(255, 255, 255, 0.9);
}

.Knob__popupValue {
  position: absolute;
  top: -2rem;
  right: 50%;
  font-size: 1rem;
  text-align: center;
  padding: 0.25rem 0.5rem;
  color: $popup-text-color;
  background-color: $popup-background-color;
  transform: translateX(50%);
  white-space: nowrap;
}

.Knob__ring {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  padding: $inner-padding;
}

$pi: 3.1416;

.Knob__ringTrackPivot {
  transform: rotateZ(135deg);
}

.Knob__ringTrack {
  // transform-origin: 50% 50%;
  fill: transparent;
  stroke: rgba(255, 255, 255, 0.1);
  stroke-width: 8;
  stroke-linecap: round;
  stroke-dasharray: 75 * $pi;
}

.Knob__ringFillPivot {
  transform: rotateZ(135deg);
}

.Knob--bipolar .Knob__ringFillPivot {
  transform: rotateZ(270deg);
}

.Knob__ringFill {
  fill: transparent;
  stroke: $ring-color;
  stroke-width: 8;
  stroke-linecap: round;
  stroke-dasharray: 100 * $pi;
  transition: stroke 50ms ease-out;
}

@each $color-name, $color-value in $fg-map {
  .Knob--color--#{$color-name} {
    .Knob__ringFill {
      stroke: $color-value;
    }
  }
}