<?php

namespace RoosterLMS\Blocks;

use RoosterLMS\Categories\Category;
use RoosterLMS\Categories\CategoryTaxonomy;
use RoosterLMS\Content\PostTypes;
use RoosterLMS\Domain\Services;
use RoosterLMS\Routing\RouteContext;

defined( 'ABSPATH' ) || exit;

final class Context {

	public static function course_id( array $attributes, ?\WP_Block $block ): int {
		$post_id = isset( $attributes['coursePost'] ) ? max( 0, (int) $attributes['coursePost'] ) : 0;
		if ( $post_id > 0 ) {
			return Services::courses()->resolve_post( $post_id );
		}
		if ( RouteContext::course_id() > 0 ) {
			return RouteContext::course_id();
		}
		$post = self::context_post( $block );
		if ( null === $post ) {
			return 0;
		}
		if ( PostTypes::COURSE === $post->post_type ) {
			return Services::courses()->resolve_post( (int) $post->ID );
		}
		if ( self::is_unit_post( $post ) ) {
			$item = self::single_placement( (int) $post->ID );
			return null === $item ? 0 : $item->course_id;
		}
		return 0;
	}

	public static function item_id( array $attributes, ?\WP_Block $block ): int {
		$post_id = isset( $attributes['lessonPost'] ) ? max( 0, (int) $attributes['lessonPost'] ) : 0;
		if ( $post_id <= 0 ) {
			if ( RouteContext::item_id() > 0 ) {
				return RouteContext::item_id();
			}
			$post = self::context_post( $block );
			if ( null === $post || ! self::is_unit_post( $post ) ) {
				return 0;
			}
			$post_id = (int) $post->ID;
		}
		$unit_id = Services::courses()->resolve_unit_post( $post_id );
		if ( $unit_id <= 0 ) {
			return 0;
		}
		if ( RouteContext::unit_id() === $unit_id && RouteContext::item_id() > 0 ) {
			return RouteContext::item_id();
		}
		$placements = Services::curriculum_repo()->placements_for_units( array( $unit_id ) )[ $unit_id ] ?? array();
		if ( RouteContext::course_id() > 0 ) {
			foreach ( $placements as $item ) {
				if ( RouteContext::course_id() === $item->course_id ) {
					return $item->id;
				}
			}
		}
		return 1 === count( $placements ) ? $placements[0]->id : 0;
	}

	public static function category_id( array $attributes, ?\WP_Block $block, CategoryTaxonomy $taxonomy, string $key = 'categoryTerm', bool $from_context = true ): int {
		unset( $block );
		$term_id = isset( $attributes[ $key ] ) && is_scalar( $attributes[ $key ] ) ? max( 0, (int) $attributes[ $key ] ) : 0;
		if ( $term_id <= 0 ) {
			if ( ! $from_context ) {
				return 0;
			}
			$term_id = self::queried_term( $taxonomy );
			if ( $term_id <= 0 ) {
				return 0;
			}
		}
		$category = Services::category_repo()->for_term( $term_id );
		return null !== $category && $category->is_active() && $category->taxonomy === $taxonomy ? $category->id : 0;
	}

	public static function parent_category_id( array $attributes, ?\WP_Block $block, CategoryTaxonomy $taxonomy ): int {
		return self::category_id( $attributes, $block, $taxonomy, 'parentTerm' );
	}

	public static function url_category( ?CategoryTaxonomy $taxonomy ): ?Category {
		$id = Request::category();
		if ( $id <= 0 ) {
			return null;
		}
		$category = Services::category_repo()->get( $id );
		if ( null === $category || ! $category->is_active() || ( null !== $taxonomy && $category->taxonomy !== $taxonomy ) ) {
			return null;
		}
		return $category;
	}

	public static function queried_term( CategoryTaxonomy $taxonomy ): int {
		if ( ! is_tax( $taxonomy->taxonomy() ) ) {
			return 0;
		}
		$term = get_queried_object();
		return $term instanceof \WP_Term && $term->taxonomy === $taxonomy->taxonomy() ? (int) $term->term_id : 0;
	}

	public static function single_placement( int $post_id ): ?\RoosterLMS\Content\Item {
		$unit_id = Services::courses()->resolve_unit_post( $post_id );
		if ( $unit_id <= 0 ) {
			return null;
		}
		$placements = Services::curriculum_repo()->placements_for_units( array( $unit_id ) )[ $unit_id ] ?? array();
		return 1 === count( $placements ) ? $placements[0] : null;
	}

	public static function is_unit_post( \WP_Post $post ): bool {
		return PostTypes::LESSON === $post->post_type || PostTypes::QUIZ === $post->post_type;
	}

	private static function context_post( ?\WP_Block $block ): ?\WP_Post {
		$post_id = null !== $block && isset( $block->context['postId'] ) ? absint( $block->context['postId'] ) : 0;
		$post    = $post_id > 0 ? get_post( $post_id ) : get_post();
		return $post instanceof \WP_Post ? $post : null;
	}
}