<?php
namespace Domain\Promotion;

class PromotionRepository
{
    private const MAX_PER_PAGE = 100;

    private $db;
    private ?string $defaultLangId = null;

    public static $condition_type = [
        1 => 'Rabat procentowy na produkty z kategorii 1 jeżeli w koszyku jest produkt z kategorii 2',
        2 => 'Rabat procentowy na produkty z kategorii 1 i 2',
        3 => 'Najtańszy produkt w koszyku (z wybranych kategorii) za X zł',
        4 => 'Rabat procentowy na cały koszyk',
        5 => 'Rabat procentowy na produkty z kategorii 1 lub 2',
    ];

    public static $discount_type = [ 1 => 'Rabat procentowy' ];

    public function __construct($db)
    {
        $this->db = $db;
    }

    /**
     * @return array{items: array<int, array<string, mixed>>, total: int}
     */
    public function listForAdmin(
        array $filters,
        string $sortColumn = 'id',
        string $sortDir = 'DESC',
        int $page = 1,
        int $perPage = 15
    ): array {
        $allowedSortColumns = [
            'id' => 'sp.id',
            'name' => 'sp.name',
            'status' => 'sp.status',
            'condition_type' => 'sp.condition_type',
            'date_from' => 'sp.date_from',
            'date_to' => 'sp.date_to',
        ];

        $sortSql = $allowedSortColumns[$sortColumn] ?? 'sp.id';
        $sortDir = strtoupper(trim($sortDir)) === 'ASC' ? 'ASC' : 'DESC';
        $page = max(1, $page);
        $perPage = min(self::MAX_PER_PAGE, max(1, $perPage));
        $offset = ($page - 1) * $perPage;

        $where = ['1 = 1'];
        $params = [];

        $name = trim((string)($filters['name'] ?? ''));
        if ($name !== '') {
            if (strlen($name) > 255) {
                $name = substr($name, 0, 255);
            }
            $where[] = 'sp.name LIKE :name';
            $params[':name'] = '%' . $name . '%';
        }

        $status = trim((string)($filters['status'] ?? ''));
        if ($status === '0' || $status === '1') {
            $where[] = 'sp.status = :status';
            $params[':status'] = (int)$status;
        }

        $whereSql = implode(' AND ', $where);

        $sqlCount = "
            SELECT COUNT(0)
            FROM pp_shop_promotion AS sp
            WHERE {$whereSql}
        ";

        $stmtCount = $this->db->query($sqlCount, $params);
        $countRows = $stmtCount ? $stmtCount->fetchAll() : [];
        $total = isset($countRows[0][0]) ? (int)$countRows[0][0] : 0;

        $sql = "
            SELECT
                sp.id,
                sp.name,
                sp.status,
                sp.condition_type,
                sp.discount_type,
                sp.amount,
                sp.date_from,
                sp.date_to,
                sp.include_coupon,
                sp.include_product_promo,
                sp.min_product_count,
                sp.price_cheapest_product
            FROM pp_shop_promotion AS sp
            WHERE {$whereSql}
            ORDER BY {$sortSql} {$sortDir}, sp.id DESC
            LIMIT {$perPage} OFFSET {$offset}
        ";

        $stmt = $this->db->query($sql, $params);
        $items = $stmt ? $stmt->fetchAll() : [];

        return [
            'items' => is_array($items) ? $items : [],
            'total' => $total,
        ];
    }

    public function find(int $promotionId): array
    {
        if ($promotionId <= 0) {
            return $this->defaultPromotion();
        }

        $promotion = $this->db->get('pp_shop_promotion', '*', ['id' => $promotionId]);
        if (!is_array($promotion)) {
            return $this->defaultPromotion();
        }

        $promotion['id'] = (int)($promotion['id'] ?? 0);
        $promotion['status'] = $this->toSwitchValue($promotion['status'] ?? 0);
        $promotion['include_coupon'] = $this->toSwitchValue($promotion['include_coupon'] ?? 0);
        $promotion['include_product_promo'] = $this->toSwitchValue($promotion['include_product_promo'] ?? 0);
        $promotion['condition_type'] = (int)($promotion['condition_type'] ?? 1);
        $promotion['discount_type'] = (int)($promotion['discount_type'] ?? 1);
        $promotion['categories'] = $this->decodeIdList($promotion['categories'] ?? null);
        $promotion['condition_categories'] = $this->decodeIdList($promotion['condition_categories'] ?? null);

        return $promotion;
    }

    public function save(array $data): ?int
    {
        $promotionId = (int)($data['id'] ?? 0);

        $row = [
            'name' => trim((string)($data['name'] ?? '')),
            'status' => $this->toSwitchValue($data['status'] ?? 0),
            'condition_type' => (int)($data['condition_type'] ?? 1),
            'discount_type' => (int)($data['discount_type'] ?? 1),
            'amount' => $this->toNullableNumeric($data['amount'] ?? null),
            'date_from' => $this->toNullableDate($data['date_from'] ?? null),
            'date_to' => $this->toNullableDate($data['date_to'] ?? null),
            'categories' => $this->encodeIdList($data['categories'] ?? null),
            'condition_categories' => $this->encodeIdList($data['condition_categories'] ?? null),
            'include_coupon' => $this->toSwitchValue($data['include_coupon'] ?? 0),
            'include_product_promo' => $this->toSwitchValue($data['include_product_promo'] ?? 0),
            'min_product_count' => $this->toNullableInt($data['min_product_count'] ?? null),
            'price_cheapest_product' => $this->toNullableNumeric($data['price_cheapest_product'] ?? null),
        ];

        if ($promotionId <= 0) {
            $this->db->insert('pp_shop_promotion', $row);
            $id = (int)$this->db->id();
            if ($id <= 0) {
                return null;
            }

            $this->invalidateActivePromotionsCache();
            \Shared\Helpers\Helpers::delete_dir('../temp/');
            return $id;
        }

        $this->db->update('pp_shop_promotion', $row, ['id' => $promotionId]);
        $this->invalidateActivePromotionsCache();
        \Shared\Helpers\Helpers::delete_dir('../temp/');

        return $promotionId;
    }

    public function delete(int $promotionId): bool
    {
        if ($promotionId <= 0) {
            return false;
        }

        $deleted = $this->db->delete('pp_shop_promotion', ['id' => $promotionId]);
        $ok = (bool)$deleted;

        if ($ok) {
            $this->invalidateActivePromotionsCache();
        }

        return $ok;
    }

    /**
     * @return array<int, array<string, mixed>>
     */
    public function categoriesTree($parentId = null): array
    {
        $rows = $this->db->select('pp_shop_categories', ['id'], [
            'parent_id' => $parentId,
            'ORDER' => ['o' => 'ASC'],
        ]);

        if (!is_array($rows)) {
            return [];
        }

        $categories = [];
        foreach ($rows as $row) {
            $categoryId = (int)($row['id'] ?? 0);
            if ($categoryId <= 0) {
                continue;
            }

            $category = $this->db->get('pp_shop_categories', '*', ['id' => $categoryId]);
            if (!is_array($category)) {
                continue;
            }

            $translations = $this->db->select('pp_shop_categories_langs', '*', ['category_id' => $categoryId]);
            $category['languages'] = [];
            if (is_array($translations)) {
                foreach ($translations as $translation) {
                    $langId = (string)($translation['lang_id'] ?? '');
                    if ($langId !== '') {
                        $category['languages'][$langId] = $translation;
                    }
                }
            }

            $category['title'] = $this->categoryTitle($category['languages']);
            $category['subcategories'] = $this->categoriesTree($categoryId);
            $categories[] = $category;
        }

        return $categories;
    }

    private function defaultPromotion(): array
    {
        return [
            'id' => 0,
            'name' => '',
            'status' => 1,
            'condition_type' => 1,
            'discount_type' => 1,
            'amount' => null,
            'date_from' => null,
            'date_to' => null,
            'categories' => [],
            'condition_categories' => [],
            'include_coupon' => 0,
            'include_product_promo' => 0,
            'min_product_count' => null,
            'price_cheapest_product' => null,
        ];
    }

    private function toSwitchValue($value): int
    {
        if (is_bool($value)) {
            return $value ? 1 : 0;
        }

        if (is_numeric($value)) {
            return ((int)$value) === 1 ? 1 : 0;
        }

        if (is_string($value)) {
            $normalized = strtolower(trim($value));
            return in_array($normalized, ['1', 'on', 'true', 'yes'], true) ? 1 : 0;
        }

        return 0;
    }

    private function toNullableInt($value): ?int
    {
        if ($value === null) {
            return null;
        }

        if (is_string($value)) {
            $value = trim($value);
            if ($value === '') {
                return null;
            }
        }

        $intValue = (int)$value;
        return $intValue > 0 ? $intValue : null;
    }

    private function toNullableNumeric($value): ?string
    {
        if ($value === null) {
            return null;
        }

        $stringValue = trim((string)$value);
        if ($stringValue === '') {
            return null;
        }

        return str_replace(',', '.', $stringValue);
    }

    private function toNullableDate($value): ?string
    {
        $date = trim((string)$value);
        if ($date === '') {
            return null;
        }

        return $date;
    }

    private function encodeIdList($values): ?string
    {
        $ids = $this->normalizeIdList($values);
        if (empty($ids)) {
            return null;
        }

        return json_encode($ids);
    }

    /**
     * @return int[]
     */
    private function decodeIdList($raw): array
    {
        if (is_array($raw)) {
            return $this->normalizeIdList($raw);
        }

        $text = trim((string)$raw);
        if ($text === '') {
            return [];
        }

        $decoded = json_decode($text, true);
        if (!is_array($decoded)) {
            return [];
        }

        return $this->normalizeIdList($decoded);
    }

    /**
     * @return int[]
     */
    private function normalizeIdList($values): array
    {
        if ($values === null) {
            return [];
        }

        if (!is_array($values)) {
            $text = trim((string)$values);
            if ($text === '') {
                return [];
            }

            if (strpos($text, ',') !== false) {
                $values = explode(',', $text);
            } else {
                $values = [$text];
            }
        }

        $ids = [];
        foreach ($values as $value) {
            $id = (int)$value;
            if ($id > 0) {
                $ids[$id] = $id;
            }
        }

        return array_values($ids);
    }

    private function categoryTitle(array $languages): string
    {
        $defaultLang = $this->defaultLanguageId();
        if ($defaultLang !== '' && isset($languages[$defaultLang]['title'])) {
            $title = trim((string)$languages[$defaultLang]['title']);
            if ($title !== '') {
                return $title;
            }
        }

        foreach ($languages as $language) {
            $title = trim((string)($language['title'] ?? ''));
            if ($title !== '') {
                return $title;
            }
        }

        return '';
    }

    private function defaultLanguageId(): string
    {
        if ($this->defaultLangId !== null) {
            return $this->defaultLangId;
        }

        $rows = $this->db->select('pp_langs', ['id', 'start', 'o'], [
            'status' => 1,
            'ORDER' => ['start' => 'DESC', 'o' => 'ASC'],
        ]);

        if (is_array($rows) && !empty($rows)) {
            $this->defaultLangId = (string)($rows[0]['id'] ?? '');
        } else {
            $this->defaultLangId = '';
        }

        return $this->defaultLangId;
    }

    private function invalidateActivePromotionsCache(): void
    {
        if (!class_exists('\Shared\Cache\CacheHandler')) {
            return;
        }

        try {
            $cache = new \Shared\Cache\CacheHandler();
            if (method_exists($cache, 'delete')) {
                $cache->delete('PromotionRepository::getActivePromotions');
            }
        } catch (\Throwable $e) {
            // Cache invalidation should not block save/delete.
        }
    }

    public function getActivePromotions()
    {
        $cacheHandler = new \Shared\Cache\CacheHandler();
        $cacheKey = "PromotionRepository::getActivePromotions";

        $objectData = $cacheHandler->get( $cacheKey );

        if ( !$objectData )
        {
            $results = $this->db->select( 'pp_shop_promotion', 'id', [ 'AND' => [ 'status' => 1, 'OR #date_from' => [ 'date_from' => null, 'date_from[<=]' => date( 'Y-m-d' ) ], 'OR #date_to' => [ 'date_to' => null, 'date_to[>=]' => date( 'Y-m-d' ) ] ], 'ORDER' => [ 'id' => 'DESC' ] ] );

            $cacheHandler->set( $cacheKey, $results );
        }
        else
        {
            return unserialize( $objectData );
        }

        return $results;
    }

    public function findPromotion( $basket )
    {
        if ( !is_array( $basket ) || empty( $basket ) )
            return is_array( $basket ) ? $basket : [];

        foreach ( $basket as $key => $val )
        {
            unset( $basket[$key]['discount_type'] );
            unset( $basket[$key]['discount_amount'] );
            unset( $basket[$key]['discount_include_coupon'] );
            unset( $basket[$key]['include_product_promo'] );
        }

        $basket_tmp = $basket;

        $results = $this->getActivePromotions();
        if ( is_array( $results ) and count( $results ) )
        {
            foreach ( $results as $row )
            {
                $promotion = $this->find( (int)$row );

                if ( $promotion['id'] <= 0 )
                    continue;

                if ( $promotion['condition_type'] == 4 )
                    return $this->applyTypeWholeBasket( $basket_tmp, $promotion );

                if ( $promotion['condition_type'] == 3 )
                    return $this->applyTypeCheapestProduct( $basket_tmp, $promotion );

                if ( $promotion['condition_type'] == 5 )
                    return $this->applyTypeCategoriesOr( $basket_tmp, $promotion );

                if ( $promotion['condition_type'] == 2 )
                    return $this->applyTypeCategoriesAnd( $basket_tmp, $promotion );

                if ( $promotion['condition_type'] == 1 )
                    return $this->applyTypeCategoryCondition( $basket_tmp, $promotion );
            }
        }
        return $basket;
    }

    // =========================================================================
    // Frontend: basket promotion logic (migrated from front\factory\ShopPromotion)
    // =========================================================================

    /**
     * Promocja na cały koszyk (condition_type=4)
     */
    public function applyTypeWholeBasket(array $basket, $promotion): array
    {
        $productRepo = new \Domain\Product\ProductRepository( $this->db );

        foreach ( $basket as $key => $val )
        {
            $product_promotion = $productRepo->isProductOnPromotion( $val['product-id'] );

            if ( !$product_promotion or $product_promotion and $promotion['include_product_promo'] )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    $basket[$key]['discount_type'] = $promotion['discount_type'];
                    $basket[$key]['discount_amount'] = $promotion['amount'];
                    $basket[$key]['discount_include_coupon'] = $promotion['include_coupon'];
                    $basket[$key]['include_product_promo'] = $promotion['include_product_promo'];
                }
            }
        }
        return $basket;
    }

    /**
     * Promocja na najtańszy produkt z kategorii 1 lub 2 (condition_type=3)
     */
    public function applyTypeCheapestProduct(array $basket, $promotion): array
    {
        $productRepo = new \Domain\Product\ProductRepository( $this->db );
        $condition_1 = false;
        $categories = $promotion['categories'];

        if ( is_array( $categories ) and is_array( $categories ) )
        {
            foreach ( $basket as $key => $val )
            {
                $product_promotion = $productRepo->isProductOnPromotion( $val['product-id'] );

                if ( !$product_promotion or $product_promotion and $promotion['include_product_promo'] )
                {
                    $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                    foreach ( $product_categories as $category_tmp )
                    {
                        if ( !$condition_1[$key] and in_array( $category_tmp['category_id'], $categories ) )
                            $condition_1[$key] = true;
                    }
                }
            }
        }

        if ( count( $condition_1 ) >= $promotion['min_product_count'] )
        {
            $cheapest_position = false;
            foreach ( $basket as $key => $val )
            {
                $price = $productRepo->getPrice( $val['product-id'] );
                if ( !$cheapest_position or $cheapest_position['price'] > $price )
                {
                    $cheapest_position['price'] = $price;
                    $cheapest_position['key'] = $key;
                }
            }

            $basket[$cheapest_position['key']]['quantity'] = 1;
            $basket[$cheapest_position['key']]['discount_type'] = 3;
            $basket[$cheapest_position['key']]['discount_amount'] = $promotion['price_cheapest_product'];
            $basket[$cheapest_position['key']]['discount_include_coupon'] = $promotion['include_coupon'];
            $basket[$cheapest_position['key']]['include_product_promo'] = $promotion['include_product_promo'];
        }

        return $basket;
    }

    /**
     * Promocja na wszystkie produkty z kategorii 1 lub 2 (condition_type=5)
     */
    public function applyTypeCategoriesOr(array $basket, $promotion): array
    {
        $productRepo = new \Domain\Product\ProductRepository( $this->db );
        $categories = $promotion['categories'];
        $condition_categories = $promotion['condition_categories'];

        foreach ( $basket as $key => $val )
        {
            $product_promotion = $productRepo->isProductOnPromotion( $val['product-id'] );

            if ( !$product_promotion or $product_promotion and $promotion['include_product_promo'] )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( in_array( $category_tmp['category_id'], $condition_categories ) or in_array( $category_tmp['category_id'], $categories ) )
                    {
                        $basket[$key]['discount_type'] = $promotion['discount_type'];
                        $basket[$key]['discount_amount'] = $promotion['amount'];
                        $basket[$key]['discount_include_coupon'] = $promotion['include_coupon'];
                        $basket[$key]['include_product_promo'] = $promotion['include_product_promo'];
                    }
                }
            }
        }
        return $basket;
    }

    /**
     * Promocja na produkty z kategorii 1 i 2 (condition_type=2)
     */
    public function applyTypeCategoriesAnd(array $basket, $promotion): array
    {
        $productRepo = new \Domain\Product\ProductRepository( $this->db );
        $condition_1 = false;
        $condition_2 = false;

        $categories = $promotion['categories'];
        $condition_categories = $promotion['condition_categories'];

        if ( is_array( $condition_categories ) and is_array( $categories ) )
        {
            foreach ( $basket as $key => $val )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( !$condition_1 and in_array( $category_tmp['category_id'], $condition_categories ) )
                    {
                        $condition_1 = true;
                    }
                }
            }

            foreach ( $basket as $key => $val )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( !$condition_2 and in_array( $category_tmp['category_id'], $categories ) )
                        $condition_2 = true;
                }
            }
        }

        if ( $condition_1 and $condition_2 )
        {
            foreach ( $basket as $key => $val )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( in_array( $category_tmp['category_id'], $categories ) or in_array( $category_tmp['category_id'], $condition_categories ) )
                    {
                        $basket[$key]['discount_type'] = $promotion['discount_type'];
                        $basket[$key]['discount_amount'] = $promotion['amount'];
                        $basket[$key]['discount_include_coupon'] = $promotion['include_coupon'];
                        $basket[$key]['include_product_promo'] = $promotion['include_product_promo'];
                    }
                }
            }
        }
        return $basket;
    }

    /**
     * Rabat procentowy na produkty z kategorii I jeżeli w koszyku jest produkt z kategorii II (condition_type=1)
     */
    public function applyTypeCategoryCondition(array $basket, $promotion): array
    {
        $productRepo = new \Domain\Product\ProductRepository( $this->db );
        $condition = false;
        $categories = $promotion['categories'];
        $condition_categories = $promotion['condition_categories'];

        if ( is_array( $condition_categories ) and is_array( $categories ) )
        {
            foreach ( $basket as $key => $val )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( in_array( $category_tmp['category_id'], $condition_categories ) )
                    {
                        $condition = true;
                    }
                }
            }
        }

        if ( $condition )
        {
            foreach ( $basket as $key => $val )
            {
                $product_categories = $productRepo->productCategoriesFront( (int) $val['product-id'] );
                foreach ( $product_categories as $category_tmp )
                {
                    if ( in_array( $category_tmp['category_id'], $categories ) )
                    {
                        $basket[$key]['discount_type'] = $promotion['discount_type'];
                        $basket[$key]['discount_amount'] = $promotion['amount'];
                        $basket[$key]['discount_include_coupon'] = $promotion['include_coupon'];
                        $basket[$key]['include_product_promo'] = $promotion['include_product_promo'];
                    }
                }
            }
        }
        return $basket;
    }
}