// Drawing mixins

// generic drawing of more complex things

@function draw_widget_edge($c:$outer_borders_color) {
// outer highlight "used" on most widgets
  @return 0 1px $c;
}

// Function to convert px values to em
@function to_em($input, $base: 16px) {
  // multiplied and divided by 1000 to make up for round() shortcoming
  $em_value: ($input / $base) * 1.091 * 1000;
  @return round($em_value) / 1000 * 1em;
}

// Mixin to convert provided font size in pt to em units
@mixin fontsize($size, $base: 16px, $unit: pt) {
  // if pt, convert into unitless value with the assumption: 1pt = 1.091px
  $adjusted_size: if($unit == pt, $size * 1.091, $size) * 1000;
  $rounded_size: round($adjusted_size / $base) / 1000;
  font-size: $rounded_size * 1em;
  // font-size: round($size) + pt;
}

@mixin draw_shadows($shadow1, $shadow2:none, $shadow3:none, $shadow4:none) {
//
// Helper function to stack up to 4 box-shadows;
//
  @if $shadow4!=none { box-shadow: $shadow1, $shadow2, $shadow3, $shadow4; }
  @else if $shadow3!=none { box-shadow: $shadow1, $shadow2, $shadow3; }
  @else if $shadow2!=none { box-shadow: $shadow1, $shadow2; }
  @else { box-shadow: $shadow1; }
}


// Text entries
@mixin entry($t, $c, $fc:$selected_bg_color) {
//
// Entries drawing function
//
// $t: entry type
// $c: text color, used to derive background color of entries
//
// possible $t values: normal, focus, insensitive
//
  transition-duration: 100ms;

  @if $t==normal {
    background-color: transparentize($c, 0.85);
    color: transparentize($c,0.3);

    @if $is_highcontrast {
      box-shadow: inset 0 0 0 1px $hc_inset_color;
    }
  }

  @if $t==focus {
    background-color: mix(transparentize($c, 0.75), $fc, 95%);
    box-shadow: inset 0 0 0 2px transparentize($fc, 0.3);
    color: $c;
    &:hover {}
  }

  @if $t==hover {
    background-color: transparentize($c, 0.75);
  }

  @if $t==insensitive {
    background-color:transparentize($c, 0.75);
    color: transparentize($c, 0.5);
  }
}

// On-screen Keyboard
@mixin keyboard_key($t, $c:$osd_bg_color, $tc:$osd_fg_color) {
//
// Keyboard key drawing function
//
// $t:    key type,
// $c:    base key color for colored* types
// $tc:   optional text color for colored* types
//
// possible $t values:
// normal, hover, active, checked, insensitive, undecorated
//

  // normal key
  @if $t==normal {
    color: $tc;
    background-color: lighten($c, 3%);
  }

  // focused key
  @if $t==focus {
    color: $tc;
    background-color: mix(lighten($c, 3%), $selected_bg_color, 90%);
    box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.4);
    &:hover {
      background-color: mix(lighten($c, 8%), $selected_bg_color, 90%);
      box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.3);
    }
    &:active {
      background-color: mix(lighten($c, 10%), $selected_bg_color, 90%);
      box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.3);
    }
  }

  // hover key
  @else if $t==hover {
    color: $tc;
    background-color: lighten($c, 7%);
  }

  // active key
  @else if $t==active {
    color: $tc;
    background-color: lighten($c, 10%);
  }

  // checked key
  @else if $t==checked {
    color: $tc;
    background-color: lighten($c, 15%);
  }

  // insensitive key
  @else if $t==insensitive {
    color: $insensitive_fg_color;
    background-color: $insensitive_bg_color;
  }

  // reset
  @else if $t==undecorated {
    background-color: transparent;
    background-image: none;
  }
}

//
// Button drawing function
//
// $t:    button type
//
// possible $t values:
// normal, focus, hover, active, checked, insensitive, default, undecorated,
//
// $c:    button bg color, derived from bg_color
// $tc:   button text color, derived from fg_color
//
// $flat:   button has no styling
// $osd:    button uses OSD styling
// $card:   button uses card styling
//

@mixin button($t, $tc:$fg_color, $c:$bg_color, $flat: false, $osd: false, $card: false){

  // background color
  $button_bg_color: mix($tc, $c, $button_mix_factor);

  // background color override for OSD elements
  @if $osd {
    $button_bg_color: transparentize($tc, 0.9);
  }

  // background color override for card elements
  @if $card {
    $button_bg_color: $card_bg_color;
  }

  // normal button
  @if $t==normal {
    color: $tc;
    background-color: $button_bg_color;
    @if $flat {
      background-color: transparent;
    }
    @if $is_highcontrast {
      box-shadow: inset 0 0 0 1px $hc_inset_color;
    }

    // card style
    @if $card {
      @if $is_highcontrast {
        background-color: mix($button_bg_color, $hc_inset_color, 50%);
      }
    }
  }

  // focused button
  @if $t==focus {
    $focus_bg_color: mix($button_bg_color, $selected_bg_color, 90%);
    color: $tc;
    background-color: $focus_bg_color;
    box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.4) !important;

    &:hover {
      background-color: if($variant == 'light', darken($focus_bg_color, 3%), lighten($focus_bg_color, 3%));
      box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.3) !important;
    }
    &:active {
      background-color: if($variant == 'light', darken($focus_bg_color, 6%), lighten($focus_bg_color, 6%));
      box-shadow: inset 0 0 0 2px transparentize($selected_bg_color, 0.3) !important;
    }

    // card style
    @if $card {
      border-color: transparent;
    }
  }

  // hover button
  @else if $t==hover {
    $hover_bg_color: if($variant == 'light', darken($button_bg_color, 3%), lighten($button_bg_color, 3%));
    color: $tc;
    background-color: $hover_bg_color;

    @if $is_highcontrast {
      background-color: mix($hover_bg_color, $hc_mix_color, 90%);
    }

    // card style
    @if $card {
      $card_hover_bg_color:  mix($tc, $card_bg_color, 4%);
      background-color: $card_hover_bg_color;

      @if $is_highcontrast {
        background-color: mix($card_hover_bg_color, $hc_inset_color, 40%);
      }
    }
  }

  // active button
  @else if $t==active {
    $active_bg_color: if($variant == 'light', darken($button_bg_color, 6%), lighten($button_bg_color, 6%));
    color: $tc;
    background-color: $active_bg_color;

    @if $is_highcontrast {
      background-color: mix($active_bg_color, $hc_mix_color, 90%);
    }

    // card style
    @if $card {
      $card_active_bg_color:  mix($tc, $card_bg_color, 7%);
      background-color: $card_active_bg_color;
    }
  }

  // checked button
  @else if $t==checked {
    $checked_bg_color:if($variant == 'light', darken($button_bg_color, 9%), lighten($button_bg_color, 9%));
    color: $tc;
    background-color: $checked_bg_color;

    &:hover { background-color: lighten($checked_bg_color, 12%);}
    &:active { background-color: lighten($checked_bg_color, 15%);}

    @if $is_highcontrast {
      background-color: mix($checked_bg_color, $hc_mix_color, 90%);
      &:hover { background-color: mix(lighten($checked_bg_color, 12%), $hc_mix_color, 90%);}
      &:active { background-color: mix(lighten($checked_bg_color, 15%), $hc_mix_color, 90%);}
    }
  }

  // insensitive button
  @else if $t==insensitive {
    color: if($variant == 'light', transparentize($tc, .6), transparentize($tc, .5));
    background-color: if($variant == 'light', transparentize($tc, .9), transparentize($tc, .95));

    @if $is_highcontrast {
      // no border since it isn't sensitive
      box-shadow: none;
    }
  }

  // default/suggested button
  @else if $t==default {
    background-color: $selected_bg_color;
    color: $selected_fg_color;

    &:focus {
      box-shadow: inset 0 0 0 2px transparentize($selected_fg_color, .4) !important;
    }
    &:hover, &:focus {
      background-color: lighten($selected_bg_color, 5%);
      color: lighten($selected_fg_color, 5%);
    }
    &:active {
      background-color: darken($selected_bg_color, 7%);
      color: darken($selected_fg_color, 7%);
    }
    &:insensitive {
      @include button(insensitive);
      background-color: transparentize($selected_bg_color, .5);
      color: transparentize($selected_fg_color, .5);
    }
  }

  // reset (unstyled button)
  @else if $t==undecorated {
    background-color: transparent;
    border-color: transparent;
    box-shadow: none;

    &:insensitive {
      @include button(insensitive);
      background-color: transparent !important;
    }
  }
}

// Helper mixin for button-like elements with an icon
@mixin tile_button($color, $flat: true) {
  @extend %tile;
  color: $color;

  // focus-color
  $fc: mix($selected_bg_color, $color, 90%);

  @if $flat {
    background-color: transparent;
    &:hover { background-color: transparentize($color, .88);}
    &:highlighted, &:focus {
      background-color: transparentize($fc, .84);
      &:hover {
        background-color: transparentize($fc, .68);
      }
    }
  } @else {
    background-color: transparentize($color, .84);
    &:hover { background-color: transparentize($color, .72);}
    &:highlighted, &:focus {
      background-color: transparentize(mix($fc, $color, 20%), .84);
      &:hover {
        background-color: transparentize(mix($fc, $color, 20%), .68);
      }
    }
  }

  // bit of a hack to have nice high contrast
  @if $is_highcontrast {
    @if $flat {
      &:hover {
        box-shadow: inset 999px 0 0 0 transparentize($color, .92);
      }
      &:highlighted, &:focus {
        box-shadow: inset 999px 0 0 0 transparentize($fc, .8);
      }
    } @else {
      box-shadow: inset 999px 0 0 0 transparentize($color, .92);
      border-color: transparentize($color, .44);
      &:highlighted, &:focus {
        box-shadow: inset 999px 0 0 0 transparentize($fc, .8);
      }
    }
  }

  &:highlighted, &:focus {
    border-color: transparentize($fc, .3);
  }

  &:active {
    background-color: transparentize($color, .76);
    &:focus {
      background-color: transparentize($fc, .68);
    }
  }

  &:selected,
  &:checked {
    background-color: transparentize($color, .81);
    &:active { background-color: transparentize($color, .78);}
    &:hover { background-color: transparentize($color, .75);}
  }

  &:drop {
    border-color: transparentize($selected_bg_color, .2);
    background-color: transparentize($selected_bg_color, .8);
  }
}

// styling for elements within popovers that look like notifications
@mixin card($flat: false) {
  @extend %card;

  @if $flat {
    @include button(undecorated, $card: false);
    &:hover {@include button(hover, $card: false);}
    &:active {@include button(active, $card: false);}
  } @else {
    @include button(normal, $card: true);
    &:hover {@include button(hover, $card: true);}
    &:active {@include button(active, $card: true);}
  }
  &:focus {@include button(focus, $card: true);}
  &:insensitive {
    @include button(insensitive, $card: true);
  }
}

// styling for all menuitems in popovers
@mixin menuitem($bg, $flat: true) {

  // lighten the background color always
  $bg: lighten($bg,5%);

  font-weight: normal;
  spacing: $base_padding;
  transition-duration: 100ms;
  padding: $base_padding * 1.5 $base_padding * 2;

  @if $flat {
    @include button(undecorated);
  } @else {
    @include button(normal, $c:$bg);
  }
  &:focus,
  &:hover {
    @include button(hover, $c:$bg);
  }
  &:active {@include button(active, $c:$bg);}
  &:checked {@include button(checked, $c:$bg);}
}

//
// Panel menu/button drawing function
//
// $bg: background color, derived from $panel_fg_color
// $fg: foreground color, also derived from $panel_fg_color
//
// $flat:               if true, the button is filled instead of transparent
// $highlighted_child:  if true, applies some special overrides for to a
//                      child element, see _panel.scss for details
// $child_class:        class name of the child element
//

@mixin panel_button($bg:$panel_fg_color, $fg:$panel_fg_color, $flat: true, $highlighted_child: false, $child_class:"") {

  transition-duration: 150ms;
  margin: 3px;
  border: 1px solid transparent;
  border-radius: $forced_circular_radius;

  font-weight: bold;
  background-color: transparent;
  color: $fg;

  @if $flat {
    box-shadow: none;

    &:active, &:focus, &:checked {
      background-color: transparentize($fg, 0.75);
      &:hover {
        background-color: transparentize($fg, 0.65);
      }
    }

    &:hover {
      background-color: transparentize($fg, 0.8);
    }

  } @else {
    background-color: transparentize($bg, 0.2);

    @if $is_highcontrast {
      border-color: $hc_inset_color;
    }

    &:active, &:focus, &:checked {
      background-color: $bg;
      &:hover {
        background-color: transparentize($bg, 0.05);
      }
    }

    &:hover {
      background-color: transparentize($bg, 0.1);
    }
  }

  @if $is_highcontrast {
    &:hover, &:active, &:focus, &:checked {
      border-color: $hc_inset_color;
    }
  }

  // some overrides to style a child element
  @if $highlighted_child {
    background: none !important;
    border: none !important;

    #{$child_class} {
      transition-duration: 150ms;
      border-radius: $forced_circular_radius;

      // use box-shadow instead of border
      @if $is_highcontrast {
        box-shadow: inset 0 0 0 1px $hc_inset_color;
      }
    }

    &:active, &:focus {
      background: none;
      box-shadow: none !important;

      #{$child_class} {
        background-color: transparentize($fg, 0.75);

        &:hover {
          background-color: transparentize($fg, 0.65) !important;
        }
      }
    }

    &:hover {
      box-shadow: none !important;
      #{$child_class} {
        background-color: transparentize($fg, 0.8);
      }
    }
  }
}