<?php

defined('ROOT_DIR') || exit;

class Search {
    public array $query;
    private string $sql_query = "";
    private array $variables = array();
    public int $count = 0;

    public function __construct($query)
    {
        $this->query = $query;
        list($sql_query, $variables) = $this->query_construct();
        $this->sql_query = $sql_query;
        $this->variables = $variables;
    }

    // Извлечение данных из базы
    public function collect($fill = true, $new = true)
    {
        global $b;
        $result = $b->db_query($this->sql_query, $this->variables, $new);
        if(!$fill) return $result;

        $this->get_count();

        $items = array();
        foreach ($result as $key => $item) {
            $class = new $item["item_class"]($item["item_id"]);
            $class->fill_main_parent($item["item_parent"]);
            $class->props_values = $this->search_props($item, $class);
            $items[] = $class;
        }
        return $items;
    }

    // Поиск параметров
    private function search_props($item, $class): array
    {
        $props = explode("-+-", $item["properties"]);
        $values = explode("-+-", $item["values"]);
        $result = array();

        for ($i = 0; $i < count($props); $i++) {
            $prop = $props[$i];
            $value = $values[$i];
            if(!isset($class->props[$prop])) continue;
            $result[$prop] = $value;
        }

        return $result;
    }

    // Получить количество элементов
    public function get_count(){
        global $b;
        list($query_count, $variables) = $this->query_construct(true);
        $result = $b->db_query($query_count, $variables, false);
        $this->count = $result[0]["count"];
        return $this;
    }

    // Создание запроса
    private function query_construct($count = false): array
    {
        $variables = array();

        $props = $this->query["props"];
        $params = $this->query["terms"] ?? array();

        if(isset($this->query["class"])) $params["item_class"] = $this->query["class"];
        if(isset($this->query["parent_id"])) $params["item_parent"] = $this->query["parent_id"];

        $limit = intval($this->query["limit"] ?? 184467440737);
        $offset = intval($this->query["offset"] ?? 0);

        $order = $this->query_order($this->query["order"]);
        $order_inner = $this->query_order_inner($this->query["order"]);

        $where_list = array();

        list($where_props, $props_var) = $this->query_props($props);
        $variables = array_merge($variables, $props_var);

        list($where, $where_var) = $this->query_where($params);
        $variables = array_merge($variables, $where_var);

        if($where_props) $where_list[] = $where_props;
        if($where) $where_list[] = $where;

        $return_fields = "COUNT(*) as count";
        $group_by = $join_props = $limit_query = $offset_query = "";

        if(!$count){
            $return_fields = " `bive_items`.* ";
            $group_by = " GROUP BY `bive_items`.`item_id` ";
            $limit_query = " LIMIT $limit ";
            $offset_query = " OFFSET $offset ";

            if(isset($params["item_class"])) {
                $return_fields = "`bive_items`.*, GROUP_CONCAT(p.prop_key SEPARATOR '-+-') AS properties, GROUP_CONCAT(p.prop_value SEPARATOR '-+-') AS `values`";
                $join_props = " JOIN `bive_items_props` p ON `bive_items`.`item_id` = p.`item_id` ";

                $class = new $params["item_class"](0);
                if(!count($class->props)) {
                    $return_fields = "`bive_items`.*";
                    $group_by = "";
                    $join_props = "";
                }
            }
        }

        $where_collect = $this->query_binary($where_list);
        $result_query = "SELECT $return_fields FROM `bive_items` $join_props $order_inner WHERE $where_collect $group_by $order $limit_query $offset_query;";
        return array($result_query, $variables);
    }

    // Соединение таблиц для сортировки
    private function query_order_inner($order): string
    {
        if(!isset($order) || !isset($order["key"])) return "";
        $key = $order["key"];
        return "INNER JOIN `bive_items_props` AS `bip` ON `bive_items`.`item_id` = `bip`.`item_id` AND `bip`.`prop_key` = '$key'";
    }

    // Сортировка
    private function query_order($order): string
    {
        if(!isset($order) || !isset($order["key"])) return "";
        $direction = $order["direction"] ?? "ASC";
        $type = $order["direction"] == "numeric" ? "CAST(`bip`.`prop_value` AS SIGNED)" : "`bip`.`prop_value`";
        return " ORDER BY $type $direction ";
    }

    private function query_binary($array, $operator = "AND"): string
    {
        return "(" . implode(" " . mb_strtoupper($operator) . " ", $array) . ")";
    }

    // Условия поиска по свойствам
    private function query_props($props, $operator = "and"): array
    {
        if(!$props || !count($props)) return array("", array());
        $sql = array();
        $variables = array();
        foreach ($props as $key => $prop) {
            if($key == "and") {
                list($query, $var) = $this->query_props($prop, "and");
                $sql[] = $query;
                $variables[] = $var;
            }else if($key == "or") {
                list($query, $var) = $this->query_props($prop, "or");
                $sql[] = $query;
                $variables[] = $var;
            } else {
                list($key, $prop, $not, $op) = $this->query_operators($key, $prop);
                $sql[] = $not . "EXISTS (
                      SELECT 1 
                      FROM bive_items_props
                      WHERE bive_items.item_id = bive_items_props.item_id 
                      AND bive_items_props.prop_key = '$key' AND bive_items_props.prop_value $op ?
                )";
                $variables[] = $prop;
            }
        }
        $string_query = $this->query_binary($sql, $operator);
        return array($string_query, $variables);
    }

    // Условия поиска по предметам
    private function query_where($where, $operator = "and"): array
    {
        if(!$where || !count($where)) return array("", array());
        $sql = array();
        $variables = array();
        foreach ($where as $key => $prop) {
            if($key == "and") {
                list($query, $var) = $this->query_where($prop, "and");
                $sql[] = $query;
                $variables = array(...$variables, ...$var);
            }else if($key == "or") {
                list($query, $var) = $this->query_where($prop, "or");
                $sql[] = $query;
                $variables[] = array(...$variables, ...$var);
            } else {
                list($key, $prop, $not, $op) = $this->query_operators($key, $prop);
                $sql[] = "$not`bive_items`.`$key` $op ?";
                $variables[] = $prop;
            }
        }
        $string_query = $this->query_binary($sql, $operator);
        return array($string_query, $variables);
    }

    private function query_operators($key, $prop): array
    {
        $not = "";
        $op = " = ";

        // Добавление отрицания
        if(mb_substr($key, 0, 1) == "!") {
            $key = substr($key, 1);
            $not = " NOT ";
        }

        // Добавление конструкции LIKE
        if(mb_substr($key, 0, 1) == "%") {
            $prop = "%" . $prop;
            $key = substr($key, 1);
            $op = " LIKE ";
        }

        // Добавление конструкции LIKE
        if(mb_substr($key, -1) == "%") {
            $prop = $prop . "%";
            $key = substr($key, 0, -1);
            $op = " LIKE ";
        }

        return array($key, $prop, $not, $op);
    }
}