//
// Drawing mixins
//
// Generic drawing of more complex things
//


//
// Scaling function
//

$ref_size: 13.3px; // = 10pt = 1em

@function rem($px, $fs: $ref_size) {
  @return ($px / $fs ) * 1rem;
}


//
// Default shadows
//

$z-depth-1: 0 1px 1px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.16);
$z-depth-2: 0 2px 2px rgba(0, 0, 0, 0.12), 0 3px 4px rgba(0, 0, 0, 0.20);
$z-depth-3: 0 5px 5px rgba(0, 0, 0, 0.16), 0 4px 4px rgba(0, 0, 0, 0.20);
$z-depth-4: 0 6px 8px -4px rgba(0, 0, 0, 0.16),
            0 10px 6px rgba(0, 0, 0, 0.20);
$z-depth-5: 0 8px 10px -4px rgba(0, 0, 0, 0.20),
            0 12px 8px rgba(0, 0, 0, 0.24);

// z-depth-1 actual shadows + dummy z-depth-2 area
$z-depth-1-backdrop: 0 2px 2px transparent,
                     0 3px 4px transparent,
                     0 3px 3px -1px rgba(0, 0, 0, 0.08);
// z-depth-2 actual shadows + dummy z-depth-4 area
$z-depth-2-backdrop: 0 10px 6px transparent,
                     0 6px 8px -4px transparent,
                     0 2px 2px rgba(0, 0, 0, 0.12),
                     0 3px 4px rgba(0, 0, 0, 0.20);


//
// Header-bar shadows
//

$header-shadow-light: 0 1px 1px rgba(0, 0, 0, 0.16),
                      0 1px 2px rgba(0, 0, 0, 0.26),
                      0 2px 3px rgba(0, 0, 0, 0.32);
$header-shadow-dark: 0 1px 1px rgba(0, 0, 0, 0.06),
                     0 1px 2px rgba(0, 0, 0, 0.14),
                     0 2px 3px rgba(0, 0, 0, 0.20);
$sub-header-shadow-light-ltr: 0 1px 1px rgba(0, 0, 0, 0.16),
                              0 1px 2px rgba(0, 0, 0, 0.26),
                              0 2px 3px rgba(0, 0, 0, 0.32),
                              -5px 0 0 -1px $inverted_dark_color,
                              -2px 0 0 -1px $borders_color;
$sub-header-shadow-dark-ltr: 0 1px 1px rgba(0, 0, 0, 0.06),
                             0 1px 2px rgba(0, 0, 0, 0.14),
                             0 2px 3px rgba(0, 0, 0, 0.20),
                             -5px 0 0 -1px $inverted_dark_color,
                             -2px 0 0 -1px $borders_color;
$sub-header-shadow-light-rtl: 0 1px 1px rgba(0, 0, 0, 0.16),
                              0 1px 2px rgba(0, 0, 0, 0.26),
                              0 2px 3px rgba(0, 0, 0, 0.32),
                              5px 0 0 -1px $inverted_dark_color,
                              2px 0 0 -1px $borders_color;
$sub-header-shadow-dark-rtl: 0 1px 1px rgba(0, 0, 0, 0.06),
                             0 1px 2px rgba(0, 0, 0, 0.14),
                             0 2px 3px rgba(0, 0, 0, 0.20),
                             5px 0 0 -1px $inverted_dark_color,
                             2px 0 0 -1px $borders_color;
$selected-header-shadow-light-ltr: 0 1px 1px rgba(0, 0, 0, 0.16),
                                   0 1px 2px rgba(0, 0, 0, 0.26),
                                   0 2px 3px rgba(0, 0, 0, 0.32),
                                   -5px 0 0 -1px $selected_bg_color,
                                   -2px 0 0 -1px $solid_dark_borders_color;
$selected-header-shadow-dark-ltr: 0 1px 1px rgba(0, 0, 0, 0.06),
                                  0 1px 2px rgba(0, 0, 0, 0.14),
                                  0 2px 3px rgba(0, 0, 0, 0.20),
                                  -5px 0 0 -1px $selected_bg_color,
                                  -2px 0 0 -1px $solid_dark_borders_color;
$selected_header-shadow-light-rtl: 0 1px 1px rgba(0, 0, 0, 0.16),
                                   0 1px 2px rgba(0, 0, 0, 0.26),
                                   0 2px 3px rgba(0, 0, 0, 0.32),
                                   5px 0 0 -1px $selected_bg_color,
                                   2px 0 0 -1px $solid_dark_borders_color;
$selected-header-shadow-dark-rtl: 0 1px 1px rgba(0, 0, 0, 0.06),
                                  0 1px 2px rgba(0, 0, 0, 0.14),
                                  0 2px 3px rgba(0, 0, 0, 0.20),
                                  5px 0 0 -1px $selected_bg_color,
                                  2px 0 0 -1px $solid_dark_borders_color;


//
// Side-bar shadows
//

$sidebar-light-ltr: inset -2px 2px 2px -2px rgba(0, 0, 0, 0.05),
                    inset -3px 3px 3px -2px rgba(0, 0, 0, 0.05);
$sidebar-light-rtl: inset 2px 2px 2px -2px rgba(0, 0, 0, 0.05),
                    inset 3px 3px 3px -2px rgba(0, 0, 0, 0.05);
$sidebar-dark-ltr: inset -2px 2px 1px -2px rgba(0, 0, 0, 0.02),
                   inset -3px 3px 3px -2px rgba(0, 0, 0, 0.06);
$sidebar-dark-rtl: inset 2px 2px 1px -2px rgba(0, 0, 0, 0.02),
                   inset 3px 3px 3px -2px rgba(0, 0, 0, 0.06);


//
// Inline-toolbar shadows
//

$inline-shadow-light: inset 0 1px 2px -1px rgba(0, 0, 0, 0.02),
                      inset 0 2px 3px -2px rgba(0, 0, 0, 0.07);
$inline-shadow-dark: inset 0 1px 2px -1px rgba(0, 0, 0, 0.03),
                     inset 0 3px 4px -3px rgba(0, 0, 0, 0.06);


//
// Info-bar shadows
//
// $infobar-shadow-light: inset 0 1px 2px rgba(0, 0, 0, 0.08);
// $infobar-shadow-dark: inset 0 1px 2px rgba(0, 0, 0, 0.04);


//
// Reorderable-tab shadows
//

$tab-shadow-light: -1px 0 2px rgba(0, 0, 0, 0.02),
                  -1px 0 4px rgba(0, 0, 0, 0.02),
                  1px 0 2px rgba(0, 0, 0, 0.02),
                  1px 0 4px rgba(0, 0, 0, 0.02);
$tab-shadow-dark: -1px 0 2px rgba(0, 0, 0, 0.02),
                  -1px 0 4px rgba(0, 0, 0, 0.03),
                  1px 0 2px rgba(0, 0, 0, 0.02),
                  1px 0 4px rgba(0, 0, 0, 0.03);


//
// Menubar shadows
//

$menubar-shadow: inset 0 2px 2px -3px rgba(0, 0, 0, 0.26),
                 inset 0 5px 3px -5px rgba(0, 0, 0, 0.39),
                 inset 0 -1px $borders_color;


//
// Toolbar shadows
//

$toolbar-shadow-light: inset 0 1px 1px rgba(0, 0, 0, 0.18),
                       inset 0 4px 2px -4px rgba(0, 0, 0, 0.20),
                       inset 0 8px 3px -5px rgba(0, 0, 0, 0.24);
$toolbar-shadow-dark: inset 0 1px 1px rgba(0, 0, 0, 0.22),
                      inset 0 4px 3px -4px rgba(0, 0, 0, 0.22),
                      inset 0 8px 3px -5px rgba(0, 0, 0, 0.24);


/******************
 * Ripple effects *
 ******************/

//
// Ripple effects
//

@keyframes ripple_effect {
//
// Ripple effect drawing function
//

  from {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.001,
                                    to(gtkalpha(currentColor, 0.1)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0));
  }
  to {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.4,
                                    to(gtkalpha(currentColor, 0.1)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.1));
  }
}

@keyframes flat_ripple_effect {
  from {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.001,
                                    to(gtkalpha(currentColor, 0.1)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.1));
  }
  to {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.4,
                                    to(gtkalpha(currentColor, 0.1)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.1));
  }
}

@keyframes list_ripple_effect {
  from {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.001,
                                    to(gtkalpha(currentColor, 0)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.05));
  }
  to {
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.4,
                                    to(gtkalpha(currentColor, 0.1)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.1));
  }
}


//
// Entries
//

@mixin entry($t, $fc:$selected_bg_color) {
//
// Entries drawing function
//
// $t: entry type
// $fc: focus color
//
// possible $t values:
// normal, focus, insensitive, flat-normal, flat-focus, flat-insensitive;
//

  @if $t==normal {
    border-radius: 0;
    -gtk-outline-radius: 0;
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($track_color),
                                to(transparent))
                                0 0 1 / 0 0 1px;
    background-color: transparent;
    color: $secondary_fg_color;
  }
  @if $t==focus {
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($fc),
                                to(transparent))
                                0 0 2 / 0 0 2px;
    color: $fg_color;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1),
                box-shadow 0 cubic-bezier(0.4, 0, 0.2, 1) 0.2s, color 0;
  }
  @if $t==insensitive {
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($track_color),
                                to(transparent))
                                0 0 1 / 0 0 1px;
    background-color: transparent;
    color: $insensitive_fg_color;
  }
  @if $t==flat-normal {
    border-radius: 0;
    -gtk-outline-radius: 0;
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($track_color),
                                to(transparent))
                                0 0 1 / 0 0 1px;
    background-color: transparent;
    color: $secondary_fg_color;
  }
  @if $t==flat-focus {
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($fc),
                                to(transparent))
                                0 0 2 / 0 0 2px;
    color: $fg_color;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1),
                box-shadow 0 cubic-bezier(0.4, 0, 0.2, 1) 0.2s, color 0;
  }
  @if $t==flat-insensitive {
    border-color: $solid_light_borders_color;
    border-image: -gtk-gradient(radial,
                                center bottom, 0,
                                center bottom, 0.5,
                                to($track_color),
                                to(transparent))
                                0 0 1 / 0 0 1px;
    color: $insensitive_fg_color;
  }
}


//
// Buttons
//

@mixin button($t, $c:$light_color, $tc:$fg_color) {
//
// Button drawing function
//
// $t:    button type,
// $c:    base button color for colored* types
// $tc:   optional text color for colored* types
//
// possible $t values:
// normal, hover, active, insensitive, checked, checked-insensitive,
// flat-normal, flat-hover, flat-active, flat-insensitive, flat-checked,
// flat-checked-insensitive, undecorated
//

  @if $t==normal {
  //
  // normal button
  //
    box-shadow: $z-depth-1,
                inset 0 1px $highlight_color;
    background-color: $c;
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.5,
                                    to(gtkalpha(currentColor, 0)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0));
    color: $secondary_fg_color;
  }

  @else if $t==hover {
  //
  // hovered button
  //
    box-shadow: $z-depth-2,
                inset 0 1px $highlight_color;
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.5,
                                    to(gtkalpha(currentColor, 0)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0));
    color: $fg_color;
  }

  @else if $t==active {
  //
  // pushed button
  //
    box-shadow: $z-depth-2,
                inset 0 1px $highlight_color;
    color: $fg_color;
    transition-duration: 0;
    animation: ripple_effect 0.2s cubic-bezier(0.4, 0, 0.2, 1) forwards;
  }
  @else if $t==insensitive {
  //
  // insensitive button
  //
    box-shadow: none;
    background-color: $track_color;
    color: if($tc!=$fg_color, $insensitive_fg_color,
                              $insensitive_secondary_fg_color);
    > label { color: inherit; }
  }
  @else if $t==checked {
  //
  // checked button
  //
    box-shadow: $z-depth-1,
                inset 0 1px $highlight_color;
    background-color: $selected_bg_color;
    color: $selected_fg_color;
  }
  @else if $t==checked-insensitive {
  //
  // checked insensitive button
  //
    box-shadow: none;
    background-color: $track_color;
    color: gtkopacity($selected_bg_color, 0.4);
    > label { color: inherit; }
  }

  @else if $t==flat-normal {
  //
  // normal flat button
  //
    box-shadow: none;
    background-color: transparent;
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.5,
                                    to(gtkalpha(currentColor, 0)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0));
  }
  @else if $t==flat-hover {
  //
  // hovered flat button
  //
    box-shadow: none;
    background-image: -gtk-gradient(radial,
                                    center center, 0,
                                    center center, 0.5,
                                    to(gtkalpha(currentColor, 0)),
                                    to(transparent)),
                      linear-gradient(to bottom, gtkalpha(currentColor, 0.1));
  }
  @else if $t==flat-active {
  //
  // pushed flat button
  //
    box-shadow: none;
    animation: flat_ripple_effect 0.2s cubic-bezier(0.4, 0, 0.2, 1) forwards;
  }
  @else if $t==flat-insensitive {
  //
  // insensitive flat button
  //
    box-shadow: none;
    background-color: transparent;
  }
  @else if $t==flat-checked {
  //
  // checked flat button
  //
    background-color: $track_color;
    color: $fg_color;
  }
  @else if $t==flat-checked-insensitive {
  //
  // checked flat insensitive button
  //
    > label { color: inherit; }
  }

  @else if $t==undecorated {
  //
  // reset
  //
    border-color: transparent;
    background-color: transparent;
    background-image: none;
    box-shadow: none;
    text-shadow: none;
    -gtk-icon-shadow: none;
  }
}


//
// Overshoot
//

@mixin overshoot($p, $t:normal, $c:$secondary_selected_bg_color) {
//
// Overshoot drawing function
//
// $p: position
// $t: type
// $c: base color
//
// possible $p values:
// top, bottom, right, left
//
// possible $t values:
// normal, backdrop
//

  $_position: center $p;

  @if ($p == left) or ($p == right) {
    $_position: $p center;
  }

  background-image: -gtk-gradient(radial,
                                  $_position, 0,
                                  $_position, 0.75,
                                  to(gtkopacity($c, 0.2)),
                                  to(transparent));

  background-repeat: no-repeat;
  background-position: $_position;

  // reset some properties to be sure to not inherit them somehow
  background-color: transparent;
  border: none;
  box-shadow: none;
}


//
// Undershoot
//

@mixin undershoot($p, $fading_color: $base_color) {
//
// Undershoot drawing function
//
// $p: position
// $fading_color: actual colour for fader
//
// possible $p values:
// top, bottom, right, left
//

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

  $_gradient_dir: $p;
  $_fader_size: 16px 32px;
  $_gradient_repeat: repeat-x;
  $_bg_pos: center $p;


  @if ($p == left) or ($p == right) {
    $_fader_size: 32px 16px;
    $_gradient_repeat: repeat-y;
    $_bg_pos: $p center;
  }

  // this is the dashed line
  background-image: linear-gradient(to $_gradient_dir,
                                    gtkopacity($fading_color, 0.01),
                                    gtkopacity($fading_color, 0.04),
                                    gtkopacity($fading_color, 0.20),
                                    gtkopacity($fading_color, 0.44),
                                    gtkopacity($fading_color, 0.94));

  padding-#{$p}: 0;
  background-size: $_fader_size;
  background-repeat: $_gradient_repeat;
  background-origin: content-box;
  background-position: $_bg_pos;
}