<?php

namespace RouterOS;

use RouterOS\Exceptions\ClientException;
use RouterOS\Exceptions\QueryException;
use RouterOS\Interfaces\QueryInterface;

/**
 * Class Query for building queries
 *
 * @package RouterOS
 * @since   0.1
 */
class Query implements QueryInterface
{
    /**
     * Array of query attributes
     *
     * @var array
     */
    private $_attributes = [];

    /**
     * Some additional operations
     *
     * @var string
     */
    private $_operations;

    /**
     * Tag of query
     *
     * @var string
     */
    private $_tag;

    /**
     * Endpoint of query
     *
     * @var string
     */
    private $_endpoint;

    /**
     * Query constructor.
     *
     * @param array|string $endpoint   Path of endpoint
     * @param array        $attributes List of attributes which should be set
     * @throws QueryException
     */
    public function __construct($endpoint, array $attributes = [])
    {
        if (\is_string($endpoint)) {
            $this->setEndpoint($endpoint);
            $this->setAttributes($attributes);
        } elseif (\is_array($endpoint)) {
            $query = array_shift($endpoint);
            $this->setEndpoint($query);
            $this->setAttributes($endpoint);
        } else {
            throw new QueryException('Specified endpoint is not correct');
        }
    }

    const AVAILABLE_OPERATORS = [
        '-',  // Does not have
        '=',  // Equal
        '>',  // More than
        '<'   // Less than
    ];

    /**
     * Where logic of query
     *
     * @param string      $key
     * @param bool        $value
     * @param string|null $operator
     * @return \RouterOS\Query
     * @throws \RouterOS\Exceptions\ClientException
     * @since 1.0.0
     */
    public function where(string $key, $value = true, string $operator = ''): self
    {
        if (!empty($operator)) {
            // If operator is available in list
            if (\in_array($operator, self::AVAILABLE_OPERATORS, true)) {
                // Overwrite key
                $key = $operator . $key;
            } else {
                throw new ClientException('Operator "' . $operator . '" in not in allowed list [' . implode(',', self::AVAILABLE_OPERATORS) . ']');
            }
        }

        $this->add('?' . $key . '=' . $value);
        return $this;
    }

    /**
     * Append additional operations
     *
     * @param string $operations
     * @return \RouterOS\Query
     * @since 1.0.0
     */
    public function operations(string $operations): self
    {
        $this->_operations = '?#' . $operations;
        return $this;
    }

    /**
     * Append tag to query (it should be at end)
     *
     * @param string $name
     * @return \RouterOS\Query
     * @since 1.0.0
     */
    public function tag(string $name): self
    {
        $this->_tag = '.tag=' . $name;
        return $this;
    }

    /**
     * Append to array yet another attribute of query
     *
     * @param string $word
     * @return  \RouterOS\Query
     */
    public function add(string $word): Query
    {
        $this->_attributes[] = $word;
        return $this;
    }

    /**
     * Get attributes array of current query
     *
     * @return  array
     */
    public function getAttributes(): array
    {
        return $this->_attributes;
    }

    /**
     * Set array of attributes
     *
     * @param array $attributes
     * @return  \RouterOS\Query
     * @since   0.7
     */
    public function setAttributes(array $attributes): Query
    {
        $this->_attributes = $attributes;
        return $this;
    }

    /**
     * Get endpoint of current query
     *
     * @return  string|null
     */
    public function getEndpoint()
    {
        return $this->_endpoint;
    }

    /**
     * Set endpoint of query
     *
     * @param string|null $endpoint
     * @return  \RouterOS\Query
     * @since   0.7
     */
    public function setEndpoint(string $endpoint = null): Query
    {
        $this->_endpoint = $endpoint;
        return $this;
    }

    /**
     * Build body of query
     *
     * @return  array
     * @throws  \RouterOS\Exceptions\QueryException
     */
    public function getQuery(): array
    {
        if ($this->_endpoint === null) {
            throw new QueryException('Endpoint of query is not set');
        }

        // Get all attributes and prepend endpoint to this list
        $attributes = $this->getAttributes();
        array_unshift($attributes, $this->_endpoint);

        // If operations is set then add to query
        if (is_string($this->_operations) && !empty($this->_operations)) {
            $attributes[] = $this->_operations;
        }

        // If tag is set then added to query
        if (is_string($this->_tag) && !empty($this->_tag)) {
            $attributes[] = $this->_tag;
        }

        return $attributes;
    }
}