////
/// @group o-assets
/// @link http://registry.origami.ft.com/components/o-assets
////

/// Default global path to assets
///
/// @type String
$o-assets-global-path: '/bower_components/' !default;

/// Cast the asset map
///
/// It should contain pairs such as `o-module: path/to/module/assets`
///
/// @type map
$o-assets-paths-map: () !default;

/// Resolve the full path to an asset
///
/// @example scss
///  el { background: url(oAssetsResolve("img/symbols-sprite.png", o-weather)); }
///
/// @param {String} $asset - path to an asset, relative to the module's root
/// @param {String} $module - name of the module
@function oAssetsResolve($asset, $module) {
	$full-path: $asset;

	// Trim forward slash at the beginning of the asset path
	// turns "/img/foo.png" into "img/foo.png"
	@if (str-index($asset, '/') == 1) {
		$full-path: str-slice($asset, 2);
	}

	@if (map-has-key($o-assets-paths-map, $module)) {
		$module-path: map-get($o-assets-paths-map, $module);

		// allows putting assets in single directory shared by all modules
		@if ($module-path) {
			$full-path: $module-path + '/' + $full-path;
		}
	} @else {
		// defaults to use module name
		$full-path: $o-assets-global-path + $module + '/' + $full-path;
	}

	@return #{$full-path};
}

/// Set asset paths for one or multiple modules
///
/// @example scss
///  @include oAssetsSetModulePaths((
///    o-header: /assets/header
///  ));
///
/// @param {Map} $path-map - Set of module names and paths
@mixin oAssetsSetModulePaths($path-map) {
	$o-assets-paths-map: map-merge($o-assets-paths-map, $path-map) !global;
}