@use "sass:map";
@use "./image-compare.config" as config;
@use "../../01-core/external" as *;

$_c: config.$ss-image-compare-config;
$_pos: var(--ss-image-compare-position);

/// Before/after slider. `ImageCompareSlider` keeps
/// `--ss-image-compare-position` (0–100%) on the container in sync with the
/// handle; without the script the split stays at the configured position.
@mixin ss-image-compare {
    --ss-image-compare-position: #{map.get($_c, position)};
    position: relative;
    display: block;
    margin: 0;
    overflow: hidden;
    user-select: none;
    touch-action: pan-y;
}

@mixin ss-image-compare-image {
    display: block;
    inline-size: 100%;
    block-size: auto;
}

/// The "before" image, clipped to the left of the divider.
@mixin ss-image-compare-overlay {
    position: absolute;
    inset: 0;
    inline-size: 100%;
    block-size: 100%;
    object-fit: cover;
    clip-path: inset(0 calc(100% - #{$_pos}) 0 0);
}

/// Divider line plus round knob; the element itself is a wide, invisible
/// hit area so it is easy to grab (WCAG 2.5.8).
@mixin ss-image-compare-handle {
    position: absolute;
    inset-block: 0;
    inset-inline-start: $_pos;
    z-index: 1;
    inline-size: map.get($_c, hit-width);
    transform: translateX(-50%);
    cursor: ew-resize;
    touch-action: none;

    &::before {
        content: "";
        position: absolute;
        inset-block: 0;
        inset-inline-start: 50%;
        inline-size: map.get($_c, divider-width);
        transform: translateX(-50%);
        background-color: map.get($_c, divider-color);
        box-shadow: 0 0 q(3) var(--ss-color-backdrop);
    }

    // Knob with two chevrons; the empty alt text keeps them out of the
    // accessible name.
    &::after {
        content: "\2039\2002\203A" / "";
        position: absolute;
        inset-block-start: 50%;
        inset-inline-start: 50%;
        display: grid;
        place-items: center;
        inline-size: map.get($_c, knob-size);
        block-size: map.get($_c, knob-size);
        transform: translate(-50%, -50%);
        font-size: var(--ss-font-size-lg);
        font-weight: 600;
        line-height: 1;
        color: map.get($_c, knob-fg);
        background-color: map.get($_c, knob-bg);
        border: q(1) solid var(--ss-color-border);
        border-radius: var(--ss-radius-full);
        box-shadow: var(--ss-a-shadow-md);
    }

    &:focus {
        outline: none;
    }

    &:focus-visible::after {
        outline: var(--ss-focus-ring-width, #{q(2)}) solid
            var(--ss-focus-ring-color, currentColor);
        outline-offset: var(--ss-focus-ring-offset, #{q(2)});
    }
}

@mixin ss-image-compare-label {
    position: absolute;
    inset-block-start: q(8);
    z-index: 1;
    padding: q(2) q(8);
    font-size: var(--ss-font-size-xs);
    font-weight: 600;
    color: map.get($_c, label-fg);
    background-color: map.get($_c, label-bg);
    border-radius: var(--ss-radius-sm);
    pointer-events: none;
}