<?php
/**
 * HeaderSelector
 * PHP version 7.4
 *
 * @category Class
 * @package  OpenAPI\Client
 * @author   OpenAPI Generator team
 * @link     https://openapi-generator.tech
 */

/**
 * Public Gateways API
 *
 * Scaleway Public Gateways are building blocks for your infrastructure on Scaleway's public cloud. They sit at the border of Private Networks and provide access to/from other networks or the Internet. As well as this, Public Gateways offer a host of managed features and services to facilitate the management of resources in your Private Network, including NAT to map private IP addresses in the Private Network to the public IP address of the Public Gateway.  (switchcolumn) <Message type=\"tip\"> To create and manage your Private Networks, check out the [VPC API](https://www.scaleway.com/en/developers/api/vpc). </Message> (switchcolumn)  ## Concepts  Refer to our [dedicated concepts page](https://www.scaleway.com/en/docs/public-gateways/concepts/) to find definitions of all terminology related to Public Gateways, including NAT, SSH bastion and more.  (switchcolumn) (switchcolumn)  ## Quickstart  1. Configure your environment variables.      <Message type=\"note\">     This is an optional step that seeks to simplify your usage of the Public Gateways API.     </Message>       ```bash     export SCW_SECRET_KEY=\"<API secret key>\"     export SCW_DEFAULT_ZONE=\"<Scaleway default Availability Zone>\"     export SCW_PROJECT_ID=\"<Scaleway Project ID>\"     ```  2. **Choose a Public Gateway type**: Public Gateways come in different shapes and sizes, with different network capabilities and pricing. When you create your Public Gateway, you need to include the required Public Gateway type in the request. Use the following call to get a list of available Public Gateway offer types and their details:      ```bash     curl -X GET \\         -H \"X-Auth-Token: $SCW_SECRET_KEY\" \\         -H \"Content-Type: application/json\" \\         \"https://api.scaleway.com/vpc-gw/v2/zones/$SCW_DEFAULT_ZONE/gateway-types\"        ```  3. **Create a Public Gateway**: run the following command to create a Public Gateway. You can customize the details in the payload (name, description, tags, etc) to your needs: use the information below to adjust the payload as necessary.      ```bash     curl -X POST \\         -H \"X-Auth-Token: $SCW_SECRET_KEY\" \\         -H \"Content-Type: application/json\" \\         \"https://api.scaleway.com/vpc-gw/v2/zones/$SCW_DEFAULT_ZONE/gateways\" \\         -d '{             \"type\": \"VPC-GW-S\",              \"name\": \"my-new-gateway\",             \"tags\": [\"my-first-tag\", \"my-second-tag\"],              \"project_id\": \"'\"$SCW_PROJECT_ID\"'\"             }'     ```      | Parameter       | Description                                         | Valid values                  |      |-----------------|-----------------------------------------------------|-------------------------------|     | type            | The type of Public Gateway (commercial offer type) to create. Use the Gateway Types endpoint to get a list of offer types. | Any valid offer type string, e.g. `VPC-GW-S` |     | name            | A name of your choice for the Public Gateway        | Any string containing only alphanumeric characters and dashes, e.g. `my-new-gateway`. |     | tags            | A list of tags to describe your Public Gateway. These can help you manage and filter your gateways. | A list of alphanumeric strings, e.g. `[\"my-first-tag`, `my-second-tag` |     | project_id      | The Scaleway Project ID to create the Public Gateway in. | A valid Scaleway Project ID, e.g. `f5fe13a0-b9c7-11ed-afa1-0242ac120002` |      **Note**: Further parameters are available, but for the purposes of this quickstart we have included only the essentials. See the `Create a Public Gateway` endpoint documentation below for full details of all possible parameters.  4. **Get a list of your Public Gateways**: run the following command to get a list of all your Public Gateways.      ```bash     curl -X GET \\         -H \"X-Auth-Token: $SCW_SECRET_KEY\" \\         -H \"Content-Type: application/json\" \\         \"https://api.scaleway.com/vpc-gw/v2/zones/$SCW_DEFAULT_ZONE/gateways\"     ```  5. **Attach a Private Network to a Public Gateway**: run the following command to attach a Private Network to your Public Gateway, and make all the Gateway's services such as NAT available to the Private Network. You can customize the details in the payload to your needs: use the information below to adjust the payload as necessary.     <Message type=\"tip\">    If you haven't created a Private Network yet, see the [Private Networks](https://www/scaleway.com/en/developers/api/vpc/) documentation to learn how to do so. Ensure you retain the ID of the Private Network.    </Message>      ```bash     curl -X POST \\         -H \"X-Auth-Token: $SCW_SECRET_KEY\" \\         -H \"Content-Type: application/json\" \\         \"https://api.scaleway.com/vpc-gw/v2/zones/$SCW_DEFAULT_ZONE/gateway-networks\" \\         -d '{             \"gateway_id\": \"b1b2edda-9364-422d-93f2-ad04e6a054dc\",              \"private_network_id\": \"548dbcc3-8b78-486f-a79a-c3f5a17642f9\",             \"enable_masquerade\": true         }'     ```      This configuration will set up the Public Gateway as a NAT gateway, masquerading traffic sent to it to the     outer internet to provide internet access to resources in the Private Network.      | Parameter       | Description                                         | Valid values                  |      |-----------------|-----------------------------------------------------|-------------------------------|     | gateway_id      | The Public Gateway ID of an existing Public Gateway | Any valid Public Gateway ID, e.g. `b1b2edda-9364-422d-93f2-ad04e6a054dc` |     | private_network_id    | The Private Network ID of an existing Private Network  | Any valid Private Network ID in the same Availability Zone as the Public Gateway, e.g. `548dbcc3-8b78-486f-a79a-c3f5a17642f9` |     | enable_masquerade     | Defines whether the gateway should masquerade traffic for the attached Private Network (i.e. whether to enable dynamic NAT) | A boolean value, e.g. `true` |      <Message type=\"note\">     Further parameters are available, but for the purposes of this quickstart we have included only the essentials. See the [Attach a gateway to a Private Network](#path-gateway-networks-attach-a-public-gateway-to-a-private-network) documentation below for full details of all possible parameters.     </Message>  6. **Delete a Public Gateway**: run the following call to delete your Public Gateway. Ensure that you replace `<PUBLIC-GATEWAY-ID>` in the URL with the ID of the Public Gateway you want to delete.      ```bash     curl -X DELETE \\         -H \"X-Auth-Token: $SCW_SECRET_KEY\" \\         -H \"Content-Type: application/json\" \\         \"https://api.scaleway.com/vpc-gw/v2/zones/$SCW_DEFAULT_ZONE/gateways/<PUBLIC-GATEWAY-ID>\"     ```      The expected successful response is empty.      (switchcolumn)     <Message type=\"requirement\">     - You have a [Scaleway account](https://console.scaleway.com/)     - You have [created an API key](https://www.scaleway.com/en/docs/iam/how-to/create-api-keys/) and that the API key has sufficient [IAM permissions](https://www.scaleway.com/en/docs/iam/reference-content/permission-sets/) to perform the actions described on this page     - You have [installed `curl`](https://curl.se/download.html)     </Message>     (switchcolumn)  ## Technical limitations  The following limitations apply to Public Gateways:  - A maximum of eight (8) Private Networks can be plugged into a single Public Gateway - Note that the Public Gateway takes some time to start up, and actions on it are impossible unless it is in the `running` state. To check the current state of a Public Gateway, use the [Get a Public Gateway](#path-gateways-get-a-public-gateway) endpoint to get information for your gateway: the `status` field of the response will tell you if it is running or in another state. - For further information about Public Gateway limitations see our [dedicated documentation](https://www.scaleway.com/en/docs/public-gateways/troubleshooting/gw-limitations/).   ## Technical information  ### Availability Zones  Public Gateways can be deployed in the following Availability Zones:  | Name      | API ID                | |-----------|-----------------------| | Paris     | `fr-par-1` `fr-par-2` | | Amsterdam | `nl-ams-1` `nl-ams-2` `nl-ams-3` | | Warsaw    | `pl-waw-1` `pl-waw-2` `pl-waw-3` |  The Scaleway Public Gateways API is a **zoned** API, meaning that each call must specify in its path parameters the Availability Zone for the resources concerned by the call.   ## Going further  For more help using Scaleway Public Gateways, check out the following resources: - Our [main documentation](https://www.scaleway.com/en/docs/public-gateways/) - The #public-gateway channel on our [Slack Community](https://www.scaleway.com/en/docs/tutorials/scaleway-slack-community/) - Our [support ticketing system](https://www.scaleway.com/en/docs/account/how-to/open-a-support-ticket/).
 *
 * The version of the OpenAPI document: v2
 * Generated by: https://openapi-generator.tech
 * Generator version: 7.11.0
 */

/**
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
 * https://openapi-generator.tech
 * Do not edit the class manually.
 */

namespace OpenAPI\Client;

/**
 * HeaderSelector Class Doc Comment
 *
 * @category Class
 * @package  OpenAPI\Client
 * @author   OpenAPI Generator team
 * @link     https://openapi-generator.tech
 */
class HeaderSelector
{
    /**
     * @param string[] $accept
     * @param string   $contentType
     * @param bool     $isMultipart
     * @return string[]
     */
    public function selectHeaders(array $accept, string $contentType, bool $isMultipart): array
    {
        $headers = [];

        $accept = $this->selectAcceptHeader($accept);
        if ($accept !== null) {
            $headers['Accept'] = $accept;
        }

        if (!$isMultipart) {
            if($contentType === '') {
                $contentType = 'application/json';
            }

            $headers['Content-Type'] = $contentType;
        }

        return $headers;
    }

    /**
     * Return the header 'Accept' based on an array of Accept provided.
     *
     * @param string[] $accept Array of header
     *
     * @return null|string Accept (e.g. application/json)
     */
    private function selectAcceptHeader(array $accept): ?string
    {
        # filter out empty entries
        $accept = array_filter($accept);

        if (count($accept) === 0) {
            return null;
        }

        # If there's only one Accept header, just use it
        if (count($accept) === 1) {
            return reset($accept);
        }

        # If none of the available Accept headers is of type "json", then just use all them
        $headersWithJson = $this->selectJsonMimeList($accept);
        if (count($headersWithJson) === 0) {
            return implode(',', $accept);
        }

        # If we got here, then we need add quality values (weight), as described in IETF RFC 9110, Items 12.4.2/12.5.1,
        # to give the highest priority to json-like headers - recalculating the existing ones, if needed
        return $this->getAcceptHeaderWithAdjustedWeight($accept, $headersWithJson);
    }

    /**
    * Detects whether a string contains a valid JSON mime type
    *
    * @param string $searchString
    * @return bool
    */
    public function isJsonMime(string $searchString): bool
    {
        return preg_match('~^application/(json|[\w!#$&.+-^_]+\+json)\s*(;|$)~', $searchString) === 1;
    }
    
    /**
    * Select all items from a list containing a JSON mime type
    *
    * @param array $mimeList
    * @return array
    */
    private function selectJsonMimeList(array $mimeList): array {
        $jsonMimeList = [];
        foreach ($mimeList as $mime) {
            if($this->isJsonMime($mime)) {
                $jsonMimeList[] = $mime;
            }
        }
        return $jsonMimeList;
    }


    /**
    * Create an Accept header string from the given "Accept" headers array, recalculating all weights
    *
    * @param string[] $accept            Array of Accept Headers
    * @param string[] $headersWithJson   Array of Accept Headers of type "json"
    *
    * @return string "Accept" Header (e.g. "application/json, text/html; q=0.9")
    */
    private function getAcceptHeaderWithAdjustedWeight(array $accept, array $headersWithJson): string
    {
        $processedHeaders = [
            'withApplicationJson' => [],
            'withJson' => [],
            'withoutJson' => [],
        ];

        foreach ($accept as $header) {

            $headerData = $this->getHeaderAndWeight($header);

            if (stripos($headerData['header'], 'application/json') === 0) {
                $processedHeaders['withApplicationJson'][] = $headerData;
            } elseif (in_array($header, $headersWithJson, true)) {
                $processedHeaders['withJson'][] = $headerData;
            } else {
                $processedHeaders['withoutJson'][] = $headerData;
            }
        }

        $acceptHeaders = [];
        $currentWeight = 1000;

        $hasMoreThan28Headers = count($accept) > 28;

        foreach($processedHeaders as $headers) {
            if (count($headers) > 0) {
                $acceptHeaders[] = $this->adjustWeight($headers, $currentWeight, $hasMoreThan28Headers);
            }
        }

        $acceptHeaders = array_merge(...$acceptHeaders);

        return implode(',', $acceptHeaders);
    }

    /**
     * Given an Accept header, returns an associative array splitting the header and its weight
     *
     * @param string $header "Accept" Header
     *
     * @return array with the header and its weight
     */
    private function getHeaderAndWeight(string $header): array
    {
        # matches headers with weight, splitting the header and the weight in $outputArray
        if (preg_match('/(.*);\s*q=(1(?:\.0+)?|0\.\d+)$/', $header, $outputArray) === 1) {
            $headerData = [
                'header' => $outputArray[1],
                'weight' => (int)($outputArray[2] * 1000),
            ];
        } else {
            $headerData = [
                'header' => trim($header),
                'weight' => 1000,
            ];
        }

        return $headerData;
    }

    /**
     * @param array[] $headers
     * @param float   $currentWeight
     * @param bool    $hasMoreThan28Headers
     * @return string[] array of adjusted "Accept" headers
     */
    private function adjustWeight(array $headers, float &$currentWeight, bool $hasMoreThan28Headers): array
    {
        usort($headers, function (array $a, array $b) {
            return $b['weight'] - $a['weight'];
        });

        $acceptHeaders = [];
        foreach ($headers as $index => $header) {
            if($index > 0 && $headers[$index - 1]['weight'] > $header['weight'])
            {
                $currentWeight = $this->getNextWeight($currentWeight, $hasMoreThan28Headers);
            }

            $weight = $currentWeight;

            $acceptHeaders[] = $this->buildAcceptHeader($header['header'], $weight);
        }

        $currentWeight = $this->getNextWeight($currentWeight, $hasMoreThan28Headers);

        return $acceptHeaders;
    }

    /**
     * @param string $header
     * @param int    $weight
     * @return string
     */
    private function buildAcceptHeader(string $header, int $weight): string
    {
        if($weight === 1000) {
            return $header;
        }

        return trim($header, '; ') . ';q=' . rtrim(sprintf('%0.3f', $weight / 1000), '0');
    }

    /**
     * Calculate the next weight, based on the current one.
     *
     * If there are less than 28 "Accept" headers, the weights will be decreased by 1 on its highest significant digit, using the
     * following formula:
     *
     *    next weight = current weight - 10 ^ (floor(log(current weight - 1)))
     *
     *    ( current weight minus ( 10 raised to the power of ( floor of (log to the base 10 of ( current weight minus 1 ) ) ) ) )
     *
     * Starting from 1000, this generates the following series:
     *
     * 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
     *
     * The resulting quality codes are closer to the average "normal" usage of them (like "q=0.9", "q=0.8" and so on), but it only works
     * if there is a maximum of 28 "Accept" headers. If we have more than that (which is extremely unlikely), then we fall back to a 1-by-1
     * decrement rule, which will result in quality codes like "q=0.999", "q=0.998" etc.
     *
     * @param int  $currentWeight varying from 1 to 1000 (will be divided by 1000 to build the quality value)
     * @param bool $hasMoreThan28Headers
     * @return int
     */
    public function getNextWeight(int $currentWeight, bool $hasMoreThan28Headers): int
    {
        if ($currentWeight <= 1) {
            return 1;
        }

        if ($hasMoreThan28Headers) {
            return $currentWeight - 1;
        }

        return $currentWeight - 10 ** floor( log10($currentWeight - 1) );
    }
}