/// Map of cubic-bezier values representing named easing values (eg. `ease-in`, `ease-out-quart`). Can be "easily" accessed with `easing`.
/// @see easing
/// @group utils
///
$easings: (
    'linear': (
        0,
        0,
        1,
        1,
    ),
    'ease': (
        0.25,
        0.1,
        0.25,
        1,
    ),
    'ease-in': (
        0.42,
        0,
        1,
        1,
    ),
    'ease-out': (
        0,
        0,
        0.58,
        1,
    ),
    'ease-in-out': (
        0.42,
        0,
        0.58,
        1,
    ),
    'ease-in-sine': (
        0.47,
        0,
        0.745,
        0.715,
    ),
    'ease-out-sine': (
        0.39,
        0.575,
        0.565,
        1,
    ),
    'ease-in-out-sine': (
        0.445,
        0.05,
        0.55,
        0.9,
    ),
    'ease-in-quad': (
        0.55,
        0.085,
        0.68,
        0.53,
    ),
    'ease-out-quad': (
        0.25,
        0.46,
        0.45,
        0.94,
    ),
    'ease-in-out-quad': (
        0.455,
        0.03,
        0.515,
        0.955,
    ),
    'ease-in-cubic': (
        0.55,
        0.055,
        0.675,
        0.19,
    ),
    'ease-out-cubic': (
        0.215,
        0.61,
        0.355,
        1,
    ),
    'ease-in-out-cubic': (
        0.645,
        0.045,
        0.355,
        1,
    ),
    'ease-in-quart': (
        0.895,
        0.03,
        0.685,
        0.22,
    ),
    'ease-out-quart': (
        0.165,
        0.84,
        0.44,
        1,
    ),
    'ease-in-out-quart': (
        0.77,
        0,
        0.175,
        1,
    ),
    'ease-in-quint': (
        0.755,
        0.05,
        0.855,
        0.06,
    ),
    'ease-out-quint': (
        0.23,
        1,
        0.32,
        1,
    ),
    'ease-in-out-quint': (
        0.86,
        0,
        0.07,
        1,
    ),
    'ease-in-expo': (
        0.95,
        0.05,
        0.795,
        0.035,
    ),
    'ease-out-expo': (
        0.19,
        1,
        0.22,
        1,
    ),
    'ease-in-out-expo': (
        1,
        0,
        0,
        1,
    ),
    'ease-in-circ': (
        0.6,
        0.04,
        0.98,
        0.335,
    ),
    'ease-out-circ': (
        0.075,
        0.82,
        0.165,
        1,
    ),
    'ease-in-out-circ': (
        0.785,
        0.135,
        0.15,
        0.86,
    ),
    'ease-in-back': (
        0.6,
        -0.28,
        0.735,
        0.045,
    ),
    'ease-out-back': (
        0.175,
        0.885,
        0.32,
        1.275,
    ),
    'ease-in-out-back': (
        0.68,
        -0.55,
        0.265,
        1.55,
    ),
    'authentic-motion': (
        0.4,
        0,
        0.2,
        1,
    ),
);

/// Takes a string representation of an cubic-bezier easing, and returns its 4-digit list value.
/// @param {string} $easing ['ease'] - Easing name
/// @see $easings
/// @group core
@function easing($easing: 'ease') {
    @if not(map-get($easings, $easing)) {
        @warn 'No easing named #{$easing}. See _t-easings.scss for a list of all available easings';
        @return map-get($easings, 'ease');
    }

    @return map-get($easings, $easing);
}

/// @alias ease
///
@function ease($easing: 'ease') {
    @return easing($easing);
}

/// Takes a string representation of an cubic-bezier easing, and returns the corresponding cubic-bezier statement.
/// @param {string} $easing ['ease'] - Easing name
/// @see $easings
/// @group core
///
@function cubic-easing($easing: 'ease') {
    @return cubic-bezier(#{easing($easing)});
}

/// @alias cubic-easing
///
@function c-ease($easing: 'ease') {
    @return cubic-easing($easing);
}

/// Generates CSS for interpolated length properties. In other words,
/// it will generate multiple values for a property over multiple media-queries.
///
/// It has 5 required parameters, including the target property, initial
/// screen size, initial value, final screen size and final value.
///
/// It has two optional parameters which include an easing property,
/// which is a string representation of a CSS animation-timing-function,
/// and finally a number of bending-points that determines how many
/// interpolations steps are applied along the easing function.
///
/// @author Original: Mike Riethmuller, New: Chris Lee
/// @group core
///
/// @param {String} $property - The CSS property to interpolate
/// @param {Unit} $min-screen - A CSS length unit
/// @param {Unit} $min-value - A CSS length unit
/// @param {Unit} $max-screen - Value to be parsed
/// @param {Unit} $max-value - Value to be parsed
/// @param {String} $easing - Value to be parsed
/// @param {Number} $bending-points - Value to be parsed
/// @link http://codepen.io/MadeByMike/pen/a2249946658b139b7625b2a58cf03a65?editors=0100
///
@mixin interpolate(
    $property,
    $min-screen,
    $min-value,
    $max-screen,
    $max-value,
    $easing: 'linear',
    $bending-points: 2
) {
    // Default Easing 'Linear'
    $p0: 0;
    $p1: 0;
    $p2: 1;
    $p3: 1;

    @if type-of($easing) == 'string' {
        $easing: map-get($easings, $easing);
    }

    // Parse Cubic Bezier string
    // Check easing for cubic-bezier values
    @if type-of($easing) == list {
        $p0: nth($easing, 1);
        $p1: nth($easing, 2);
        $p2: nth($easing, 3);
        $p3: nth($easing, 4);
    }

    #{$property}: $min-value;

    @if ($easing == 'linear' or $bending-points < 1) {
        @media screen and (min-width: $min-screen) {
            #{$property}: calc-interpolation(
                $min-screen,
                $min-value,
                $max-screen,
                $max-value
            );
        }
    } @else {
        // Loop through bending points
        $t: 1 / ($bending-points + 1);
        $i: 1;
        $prev-screen: $min-screen;
        $prev-value: $min-value;

        @while $t * $i <= 1 {
            $bending-point: $t * $i;
            $value: solve-cubic-bezier($p0, $p1, $p2, $p3, $bending-point);
            $screen-int: lerp($min-screen, $max-screen, $bending-point);
            $value-int: lerp($min-value, $max-value, $value);

            @media screen and (min-width: $prev-screen) {
                #{$property}: calc-interpolation(
                    $prev-screen,
                    $prev-value,
                    $screen-int,
                    $value-int
                );
            }

            $prev-screen: $screen-int;
            $prev-value: $value-int;
            $i: $i + 1;
        }
    }
    @media screen and (min-width: $max-screen) {
        #{$property}: $max-value;
    }
}