import type { ProductVariantInput, TargetingRule, WidgetSizeConfig } from './types';

export function sizeFeatureEnabled(
	rule: TargetingRule | undefined,
	categories: string[],
	productId: string
): boolean {
	if ( ! rule || ( rule.mode !== 'include' && rule.mode !== 'exclude' ) ) return true;
	const matched = categories.some( ( category ) => ( rule.categories || [] ).includes( category ) ) ||
		( rule.productIds || [] ).map( String ).includes( String( productId ) );
	return rule.mode === 'include' ? matched : ! matched;
}

export function sizeGuideForProduct(
	size: WidgetSizeConfig,
	categories: string[],
	variants: ProductVariantInput[]
) {
	if ( ! Array.isArray( size.guides ) ) {
		const availableLabels = variants
			.filter( ( variant ) => variant.available === true )
			.map( ( variant ) => variant.size_label );
		return size.hasSizeGuide && availableLabels.length > 0 ? { labels: availableLabels } : null;
	}
	const assigned = size.guides.find( ( guide ) =>
		( guide.categories?.categories || [] ).some( ( category ) => categories.includes( category ) )
	);
	const fallback = size.guides.find( ( guide ) => ( guide.categories?.categories || [] ).length === 0 );
	const guide = assigned || fallback || null;
	if ( ! guide ) return null;
	return guide.labels.some( ( label ) =>
		variants.some( ( variant ) => variant.available && variant.size_label === label )
	) ? guide : null;
}

export function isSizeEligible(
	size: WidgetSizeConfig | undefined,
	categories: string[],
	productId: string,
	variants: ProductVariantInput[]
): boolean {
	if ( ! size?.hasSizeGuide || ! variants.some( ( variant ) => variant.available === true ) ) return false;
	return sizeFeatureEnabled( size.targeting, categories, productId ) &&
		sizeGuideForProduct( size, categories, variants ) !== null;
}

export function sizeGuideResolution(
	size: WidgetSizeConfig,
	categories: string[],
	variants: ProductVariantInput[]
): 'collection' | 'shop_default' | 'none' {
	const guide = sizeGuideForProduct( size, categories, variants );
	if ( ! guide ) return 'none';
	if ( ! ( 'categories' in guide ) ) return 'shop_default';
	return ( guide.categories?.categories || [] ).length > 0 ? 'collection' : 'shop_default';
}