// generic drawing of more complex things

//
// Ripple keyframes
//

@keyframes ripple {
  to {
    background-size: 1000% 1000%;
  }
}

@keyframes ripple-on-slider {
  to {
    background-size: auto, 1000% 1000%;
  }
}

@keyframes ripple-on-headerbar {
  from {
    background-image: radial-gradient(circle, $primary 0%, transparent 0%);
  }

  to {
    background-image: radial-gradient(circle, $primary 100%, transparent 100%);
  }
}


@mixin entry($t, $fc: $primary) {
//
// entry
//
// $t: entry type
// $fc: focus color
//

  @if $t == normal {
    transition: $transition, border-image $ripple-fade-in-duration $ease-out;
    border-image:
      radial-gradient(
        circle closest-corner at center calc(100% - 1px),
        $fc 0%,
        transparent 0%
      ) 2 / 0 0 0px;
    box-shadow: inset 0 -1px if($fc == $primary, stroke($on-surface), $fc);
    background-color: entry-fill($on-surface);
    color: $on-surface;
    caret-color: $fc;
  }

  @if $t == hover {
    box-shadow: inset 0 -1px if($fc == $primary, stroke($on-surface), $fc);
    background-color: overlay("hover-alt", $on-surface, $on: entry-fill($on-surface));
  }

  @if $t == focus {
    box-shadow: inset 0 -1px if($fc == $primary, stroke($on-surface), $fc);
    background-color: overlay("focus", $on-surface, $on: entry-fill($on-surface));
  }

  @if $t == checked {
    border-image:
      radial-gradient(
        circle closest-corner at center calc(100% - 1px),
        $fc 100%,
        transparent 100%
      ) 2 / 0 0 2px;
    box-shadow: inset 0 -1px if($fc == $primary, stroke($on-surface), $fc);
    background-color: overlay("focus", $on-surface, $on: entry-fill($on-surface));
  }

  @if $t == disabled {
    box-shadow: inset 0 -1px disabled-stroke($on-surface);
    background-color: entry-fill($on-surface);
    color: disabled($on-surface);
  }

  @if $t == raised-normal {
    transition: $transition;
    border-image: none;
    box-shadow: $shadow-z1;
    background-color: if($fc == $primary, $surface-z8, $fc);
    color: if($fc == $primary, $on-surface, on($fc));
    caret-color: if($fc == $primary, $fc, on($fc));
  }

  @if $t == raised-hover {
    box-shadow: $shadow-z3;
  }

  @if $t == raised-focus {
    border-image: none;
    box-shadow: $shadow-z3;
  }

  @if $t == raised-disabled {
    box-shadow: $shadow-z1;
    background-color: $surface-z1;
    color: disabled($on-surface);
  }
}


$ripple-transition-property: all, border-image, background-size, background-image;
$ripple-transition-duration: $duration, $ripple-fade-in-duration, $ripple-fade-out-duration, $ripple-fade-out-opacity-duration;
$ripple-active-transition-duration: $duration, $ripple-fade-in-duration, 0ms, 0ms;

%ripple {
  transition-property: $ripple-transition-property;
  transition-duration: $ripple-transition-duration;
  transition-timing-function: $ease-out;
  background-image: radial-gradient(circle, transparent 10%, transparent 10%);
  background-repeat: no-repeat;
  background-position: center;
  background-size: 1000% 1000%;

  &:active {
    transition-duration: $ripple-active-transition-duration;
    animation: ripple $ripple-fade-in-duration $ease-out forwards;
    background-size: 0% 0%;
  }
}

@mixin ink-color($color, $on: transparent, $button-style: "none", $hover-alt: false, $opacity-modifier: 0) {
  $hover: "hover";

  @if $hover-alt or $button-style == "raised" {
    $hover: "hover-alt";
  }

  @if $button-style == "flat" {
    box-shadow: none;
  } @else if $button-style == "outlined" {
    box-shadow: inset 0 0 0 1px stroke($on-surface);
  } @else if $button-style == "raised" {
    box-shadow: $shadow-z2;
  }

  @if $button-style != "none" or $on != transparent {
    background-color: $on;
  }

  &:drop(active),
  &:hover {
    @if $button-style == "flat" {
      box-shadow: none;
    } @else if $button-style == "outlined" {
      box-shadow: inset 0 0 0 1px stroke($on-surface);
    } @else if $button-style == "raised" {
      box-shadow: $shadow-z4;
    }

    background-color: overlay($hover, $color, $opacity-modifier: $opacity-modifier, $on: $on);
  }

  &:focus {
    @if $button-style == "flat" {
      box-shadow: none;
    } @else if $button-style == "outlined" {
      box-shadow: inset 0 0 0 1px stroke($on-surface);
    } @else if $button-style == "raised" {
      box-shadow: $shadow-z4;
    }

    background-color: overlay("focus", $color, $opacity-modifier: $opacity-modifier, $on: $on);
  }

  &:active {
    @if $button-style == "flat" {
      box-shadow: none;
    } @else if $button-style == "outlined" {
      box-shadow: inset 0 0 0 1px stroke($on-surface);
    } @else if $button-style == "raised" {
      box-shadow: $shadow-z8;
    }

    background-image: radial-gradient(circle, overlay("pressed", $color, $opacity-modifier: $opacity-modifier) 10%, transparent 10%);
  }
}

@mixin list-item {
  &:drop(active):not(:active),
  &:hover:not(:active) {
    transition-property: $ripple-transition-property, background-color;
    transition-duration: $ripple-transition-duration, 0ms;
  }
}


@mixin overshoot($position) {
  $valid-positions: top, bottom, left, right;

  @if not index($valid-positions, $position) {
    @error "#{$position} is not a valid position. Expected one of #{$valid-positions}.";
  }

  $background-size: 200% 75%;

  @if $position == left or $position == right {
    $background-size: 75% 200%;
  }

  background-image:
    radial-gradient(
      farthest-side at $position,
      rgba($primary, .24) 99%, // For better antialiasing
      rgba($primary, 0) 100% // Don't use transparent i.e. rgba(0, 0, 0, 0)
    );
  background-size: $background-size;
  background-repeat: no-repeat;
  background-position: $position;
}


@mixin undershoot($side) {
  $valid-sides: top, bottom, left, right;

  @if not index($valid-sides, $side) {
    @error "#{$side} is not a valid side. Expected one of #{$valid-sides}.";
  }

  $_undershoot_color_dark: stroke($on-surface);
  $_undershoot_color_light: transparent;

  $_gradient_dir: left;
  $_dash_bg_size: 12px 1px;
  $_gradient_repeat: repeat-x;
  $_bg_pos: left $side;

  @if $side == left or $side == right {
    $_gradient_dir: top;
    $_dash_bg_size: 1px 12px;
    $_gradient_repeat: repeat-y;
    $_bg_pos: $side top;
  }

  background-color: transparent; // shouldn't be needed, but better to be sure

  background-image: linear-gradient(to $_gradient_dir, // this is the dashed line
                                    $_undershoot_color_light 50%,
                                    $_undershoot_color_dark 50%);

  margin-#{$side}: 1px;
  background-size: $_dash_bg_size;
  background-repeat: $_gradient_repeat;
  background-origin: content-box;
  background-position: $_bg_pos;
}