<?php
/**
 * Resolves threshold profile for evaluation.
 *
 * @package Kayvandra\MarginBeacon
 */

declare(strict_types=1);

namespace Kayvandra\MarginBeacon\Application\Threshold;

use Kayvandra\MarginBeacon\Domain\Risk\SeverityClassifier;
use Kayvandra\MarginBeacon\Support\Constants;

/**
 * Loads global threshold; category overrides are Pro-only via filter (PRD FR-011 / §10.3).
 */
final class ThresholdResolver {

	/**
	 * Resolve global profile from settings.
	 *
	 * @return ThresholdProfile
	 */
	public function resolve_global() {
		$settings = get_option( Constants::OPTION_SETTINGS, array() );
		if ( ! is_array( $settings ) || empty( $settings['thresholds'] ) || ! is_array( $settings['thresholds'] ) ) {
			return ThresholdProfile::defaults();
		}
		$t = $settings['thresholds'];
		try {
			return new ThresholdProfile(
				isset( $t['critical_below'] ) ? (int) $t['critical_below'] : 0,
				isset( $t['high_below'] ) ? (int) $t['high_below'] : 30000,
				isset( $t['warning_below'] ) ? (int) $t['warning_below'] : 100000
			);
		} catch ( \InvalidArgumentException $e ) {
			return ThresholdProfile::defaults();
		}
	}

	/**
	 * Build classification candidates for a product's categories.
	 *
	 * Free supplies the global candidate only. Pro injects category overrides via filter.
	 *
	 * @param int[] $category_ids Product category term IDs.
	 * @return array<int,array{term_id:?int,profile:array,source:string}>
	 */
	public function candidates_for_categories( array $category_ids ) {
		$global     = $this->resolve_global()->to_array();
		$candidates = array(
			array(
				'term_id' => null,
				'profile' => $global,
				'source'  => 'global',
			),
		);

		/**
		 * Pro may replace/extend candidates with category overrides.
		 *
		 * @param array $candidates   Global-only candidates.
		 * @param int[] $category_ids Category term IDs.
		 * @param array $global       Global threshold profile array.
		 */
		$filtered = apply_filters( 'aksmb_threshold_candidates', $candidates, $category_ids, $global );
		return is_array( $filtered ) && ! empty( $filtered ) ? $filtered : $candidates;
	}

	/**
	 * Classify a line/product using global or Pro category precedence.
	 *
	 * @param \Kayvandra\MarginBeacon\Domain\Money\MoneyAmount|null $revenue       Revenue.
	 * @param \Kayvandra\MarginBeacon\Domain\Money\MoneyAmount|null $cogs          COGS.
	 * @param int[]                                                 $category_ids  Category term IDs.
	 * @param bool                                                  $complete      Evaluation complete.
	 * @param SeverityClassifier|null                               $classifier    Optional classifier.
	 * @return array
	 */
	public function classify_for_categories( $revenue, $cogs, array $category_ids, $complete, $classifier = null ) {
		$candidates = $this->candidates_for_categories( $category_ids );
		$classifier = $classifier instanceof SeverityClassifier ? $classifier : new SeverityClassifier();

		/**
		 * Pro multi-category precedence. Free falls back to single-candidate classify.
		 *
		 * @param array|null           $result     Prior result.
		 * @param mixed                $revenue    Revenue.
		 * @param mixed                $cogs       COGS.
		 * @param bool                 $complete   Complete.
		 * @param array                $candidates Candidates.
		 * @param SeverityClassifier   $classifier Classifier.
		 */
		$filtered = apply_filters( 'aksmb_classify_threshold_candidates', null, $revenue, $cogs, $complete, $candidates, $classifier );
		if ( is_array( $filtered ) ) {
			return $filtered;
		}

		// Free-only: classify against the first (global) candidate.
		$candidate = $candidates[0];
		$profile   = isset( $candidate['profile'] ) && is_array( $candidate['profile'] )
			? $candidate['profile']
			: ThresholdProfile::defaults()->to_array();
		$result    = $classifier->classify( $revenue, $cogs, $profile, (bool) $complete );
		return array(
			'severity'                => (string) $result['severity'],
			'gross_profit'            => $result['gross_profit'],
			'severity_basis'          => isset( $result['severity_basis'] ) && is_array( $result['severity_basis'] ) ? $result['severity_basis'] : array(),
			'reason_code'             => $result['reason_code'],
			'thresholds'              => array(
				'critical_below' => (int) $profile['critical_below'],
				'high_below'     => (int) $profile['high_below'],
				'warning_below'  => (int) $profile['warning_below'],
			),
			'source'                  => isset( $candidate['source'] ) ? (string) $candidate['source'] : 'global',
			'category_id'             => array_key_exists( 'term_id', $candidate ) && null !== $candidate['term_id']
				? (int) $candidate['term_id']
				: null,
			'considered_category_ids' => array(),
		);
	}

	/**
	 * Category refs payload for persistence (bounded IDs + resolution meta).
	 *
	 * @param array $resolution Output of classify_for_categories / precedence.
	 * @return array{considered:int[],resolved_category_id:?int,source:string}
	 */
	public static function category_refs_payload( array $resolution ) {
		return array(
			'considered'           => isset( $resolution['considered_category_ids'] ) && is_array( $resolution['considered_category_ids'] )
				? array_values( array_map( 'intval', $resolution['considered_category_ids'] ) )
				: array(),
			'resolved_category_id' => isset( $resolution['category_id'] ) ? $resolution['category_id'] : null,
			'source'               => isset( $resolution['source'] ) ? (string) $resolution['source'] : 'global',
		);
	}
}