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function wp_get_typography_font_size_value( $preset, $settings = array() ) {
	if ( ! isset( $preset['size'] ) ) {
		return null;
	}

	/*
	 * Catches falsy values and 0/'0'. Fluid calculations cannot be performed on `0`.
	 * Also returns early when a preset font size explicitly disables fluid typography with `false`.
	 */
	$fluid_font_size_settings = $preset['fluid'] ?? null;
	if ( false === $fluid_font_size_settings || empty( $preset['size'] ) ) {
		return $preset['size'];
	}

	/*
	 * As a boolean (deprecated since 6.6), $settings acts as an override to switch fluid typography "on" (`true`) or "off" (`false`).
	 */
	if ( is_bool( $settings ) ) {
		_deprecated_argument( __FUNCTION__, '6.6.0', __( '`boolean` type for second argument `$settings` is deprecated. Use `array()` instead.' ) );
		$settings = array(
			'typography' => array(
				'fluid' => $settings,
			),
		);
	}

	// Fallback to global settings as default.
	$global_settings = wp_get_global_settings();
	$settings        = wp_parse_args(
		$settings,
		$global_settings
	);

	$typography_settings = $settings['typography'] ?? array();

	/*
	 * Return early when fluid typography is disabled in the settings, and there
	 * are no local settings to enable it for the individual preset.
	 *
	 * If this condition isn't met, either the settings or individual preset settings
	 * have enabled fluid typography.
	 */
	if ( empty( $typography_settings['fluid'] ) && empty( $fluid_font_size_settings ) ) {
		return $preset['size'];
	}

	$fluid_settings  = isset( $typography_settings['fluid'] ) ? $typography_settings['fluid'] : array();
	$layout_settings = isset( $settings['layout'] ) ? $settings['layout'] : array();

	// Defaults.
	$default_maximum_viewport_width       = '1600px';
	$default_minimum_viewport_width       = '320px';
	$default_minimum_font_size_factor_max = 0.75;
	$default_minimum_font_size_factor_min = 0.25;
	$default_scale_factor                 = 1;
	$default_minimum_font_size_limit      = '14px';

	// Defaults overrides.
	$minimum_viewport_width = isset( $fluid_settings['minViewportWidth'] ) ? $fluid_settings['minViewportWidth'] : $default_minimum_viewport_width;
	$maximum_viewport_width = isset( $layout_settings['wideSize'] ) && ! empty( wp_get_typography_value_and_unit( $layout_settings['wideSize'] ) ) ? $layout_settings['wideSize'] : $default_maximum_viewport_width;
	if ( isset( $fluid_settings['maxViewportWidth'] ) ) {
		$maximum_viewport_width = $fluid_settings['maxViewportWidth'];
	}
	$has_min_font_size       = isset( $fluid_settings['minFontSize'] ) && ! empty( wp_get_typography_value_and_unit( $fluid_settings['minFontSize'] ) );
	$minimum_font_size_limit = $has_min_font_size ? $fluid_settings['minFontSize'] : $default_minimum_font_size_limit;

	// Try to grab explicit min and max fluid font sizes.
	$minimum_font_size_raw = isset( $fluid_font_size_settings['min'] ) ? $fluid_font_size_settings['min'] : null;
	$maximum_font_size_raw = isset( $fluid_font_size_settings['max'] ) ? $fluid_font_size_settings['max'] : null;

	// Font sizes.
	$preferred_size = wp_get_typography_value_and_unit( $preset['size'] );

	// Protects against unsupported units.
	if ( empty( $preferred_size['unit'] ) ) {
		return $preset['size'];
	}

	/*
	 * Normalizes the minimum font size limit according to the incoming unit,
	 * in order to perform comparative checks.
	 */
	$minimum_font_size_limit = wp_get_typography_value_and_unit(
		$minimum_font_size_limit,
		array(
			'coerce_to' => $preferred_size['unit'],
		)
	);

	// Don't enforce minimum font size if a font size has explicitly set a min and max value.
	if ( ! empty( $minimum_font_size_limit ) && ( ! $minimum_font_size_raw && ! $maximum_font_size_raw ) ) {
		/*
		 * If a minimum size was not passed to this function
		 * and the user-defined font size is lower than $minimum_font_size_limit,
		 * do not calculate a fluid value.
		 */
		if ( $preferred_size['value'] <= $minimum_font_size_limit['value'] ) {
			return $preset['size'];
		}
	}

	// If no fluid max font size is available use the incoming value.
	if ( ! $maximum_font_size_raw ) {
		$maximum_font_size_raw = $preferred_size['value'] . $preferred_size['unit'];
	}

	/*
	 * If no minimumFontSize is provided, create one using
	 * the given font size multiplied by the min font size scale factor.
	 */
	if ( ! $minimum_font_size_raw ) {
		$preferred_font_size_in_px = 'px' === $preferred_size['unit'] ? $preferred_size['value'] : $preferred_size['value'] * 16;

		/*
		 * The scale factor is a multiplier that affects how quickly the curve will move towards the minimum,
		 * that is, how quickly the size factor reaches 0 given increasing font size values.
		 * For a - b * log2(), lower values of b will make the curve move towards the minimum faster.
		 * The scale factor is constrained between min and max values.
		 */
		$minimum_font_size_factor     = min( max( 1 - 0.075 * log( $preferred_font_size_in_px, 2 ), $default_minimum_font_size_factor_min ), $default_minimum_font_size_factor_max );
		$calculated_minimum_font_size = round( $preferred_size['value'] * $minimum_font_size_factor, 3 );

		// Only use calculated min font size if it's > $minimum_font_size_limit value.
		if ( ! empty( $minimum_font_size_limit ) && $calculated_minimum_font_size <= $minimum_font_size_limit['value'] ) {
			$minimum_font_size_raw = $minimum_font_size_limit['value'] . $minimum_font_size_limit['unit'];
		} else {
			$minimum_font_size_raw = $calculated_minimum_font_size . $preferred_size['unit'];
		}
	}

	$fluid_font_size_value = wp_get_computed_fluid_typography_value(
		array(
			'minimum_viewport_width' => $minimum_viewport_width,
			'maximum_viewport_width' => $maximum_viewport_width,
			'minimum_font_size'      => $minimum_font_size_raw,
			'maximum_font_size'      => $maximum_font_size_raw,
			'scale_factor'           => $default_scale_factor,
		)
	);

	if ( ! empty( $fluid_font_size_value ) ) {
		return $fluid_font_size_value;
	}

	return $preset['size'];
}