<?php

declare(strict_types=1);

namespace App\Framework\HttpClient;

use App\Framework\Http\HeaderManipulator;
use App\Framework\Http\Headers;
use App\Framework\Http\Status;
use App\Framework\HttpClient\Curl\Handle;
use App\Framework\HttpClient\Exception\CurlExecutionFailed;
use App\Framework\HttpClient\Exception\CurlNotInitialized;

final readonly class CurlHttpClient implements HttpClient
{
    public function __construct(
        private CurlResponseParser    $responseParser = new CurlResponseParser(),
        private AuthenticationHandler $authenticationHandler = new AuthenticationHandler(),
        private CurlRequestBuilder    $requestBuilder = new CurlRequestBuilder(),
    ) {
    }

    /**
     * @throws CurlExecutionFailed
     */
    public function send(ClientRequest $request): ClientResponse
    {
        // Initialize OOP curl handle
        $handle = new Handle();

        try {
            // Build options using HandleOption enum
            $options = $this->requestBuilder->buildOptions($request);

            // Handle authentication
            if ($request->options->auth !== null) {
                $authResult = $this->authenticationHandler->configure($request->options->auth, $request->headers);

                if ($authResult->headers !== $request->headers) {
                    $updatedRequest = $request->with(['headers' => $authResult->headers]);
                    $options = $this->requestBuilder->buildOptions($updatedRequest);
                }

                if (! empty($authResult->curlOptions)) {
                    $options = array_replace($options, $authResult->curlOptions);
                }
            }

            // Set all options using fluent API
            $handle->setOptions($options);

            // Execute request (automatically uses CURLOPT_RETURNTRANSFER)
            $rawResponse = $handle->fetch();

            // Parse response using underlying CurlHandle resource
            return $this->responseParser->parse($rawResponse, $handle->getResource());
        } catch (\Throwable $e) {
            // Wrap any exception in CurlExecutionFailed for backward compatibility
            throw new CurlExecutionFailed($e->getMessage(), $e->getCode(), $e);
        }
    }

    /**
     * Send request with streaming response to destination
     *
     * Streams HTTP response directly to a writable stream resource.
     * Useful for large file downloads without loading entire response into memory.
     *
     * @param ClientRequest $request HTTP request to send
     * @param resource $destination Writable stream resource (e.g., fopen('file.txt', 'w'))
     * @return StreamingResponse Response with headers and status, but no body (streamed to destination)
     * @throws CurlExecutionFailed If request execution fails
     */
    public function sendStreaming(ClientRequest $request, $destination): StreamingResponse
    {
        if (! is_resource($destination)) {
            throw new \InvalidArgumentException('Destination must be a valid stream resource');
        }

        $handle = new Handle();

        try {
            // Build options using HandleOption enum
            $options = $this->requestBuilder->buildOptions($request);

            // Remove CURLOPT_RETURNTRANSFER (we're streaming to destination)
            unset($options[\App\Framework\HttpClient\Curl\HandleOption::ReturnTransfer->value]);

            // Handle authentication
            if ($request->options->auth !== null) {
                $authResult = $this->authenticationHandler->configure($request->options->auth, $request->headers);

                if ($authResult->headers !== $request->headers) {
                    $updatedRequest = $request->with(['headers' => $authResult->headers]);
                    $options = $this->requestBuilder->buildOptions($updatedRequest);
                    unset($options[\App\Framework\HttpClient\Curl\HandleOption::ReturnTransfer->value]);
                }

                if (! empty($authResult->curlOptions)) {
                    $options = array_replace($options, $authResult->curlOptions);
                }
            }

            // Enable header capture for streaming
            $headerBuffer = '';
            $headerFunction = function ($ch, $header) use (&$headerBuffer) {
                $headerBuffer .= $header;
                return strlen($header);
            };
            $options[\App\Framework\HttpClient\Curl\HandleOption::HeaderFunction->value] = $headerFunction;

            // Set all options
            $handle->setOptions($options);

            // Execute and stream directly to destination
            $handle->execute($destination);

            // Parse response headers from buffer
            $statusCode = $handle->getInfo(\App\Framework\HttpClient\Curl\Info::ResponseCode);
            $status = \App\Framework\Http\Status::from((int) $statusCode);
            $headers = $this->responseParser->parseHeaders($headerBuffer);

            // Get bytes written (if available)
            $bytesWritten = (int) ($handle->getInfo(\App\Framework\HttpClient\Curl\Info::SizeDownload) ?: 0);

            return new StreamingResponse(
                status: $status,
                headers: $headers,
                bytesWritten: $bytesWritten
            );
        } catch (\Throwable $e) {
            throw new CurlExecutionFailed($e->getMessage(), $e->getCode(), $e);
        }
    }

    /**
     * Send request with streaming body from source
     *
     * Streams HTTP request body from a readable stream resource.
     * Useful for large file uploads without loading entire file into memory.
     *
     * @param ClientRequest $request HTTP request to send (body will be replaced by stream)
     * @param resource $source Readable stream resource (e.g., fopen('file.txt', 'r'))
     * @param int|null $contentLength Content-Length in bytes (null for chunked transfer)
     * @return ClientResponse HTTP response
     * @throws CurlExecutionFailed If request execution fails
     */
    public function sendStreamingUpload(ClientRequest $request, $source, ?int $contentLength = null): ClientResponse
    {
        if (! is_resource($source)) {
            throw new \InvalidArgumentException('Source must be a valid stream resource');
        }

        $handle = new Handle();

        try {
            // Build options using HandleOption enum
            $options = $this->requestBuilder->buildOptions($request);

            // Remove CURLOPT_POSTFIELDS (we're using stream)
            unset($options[\App\Framework\HttpClient\Curl\HandleOption::PostFields->value]);

            // Set streaming upload options
            $options[\App\Framework\HttpClient\Curl\HandleOption::Upload->value] = true;
            $options[\App\Framework\HttpClient\Curl\HandleOption::InFile->value] = $source;

            if ($contentLength !== null) {
                $options[\App\Framework\HttpClient\Curl\HandleOption::InFileSize->value] = $contentLength;
            }

            // Handle authentication
            if ($request->options->auth !== null) {
                $authResult = $this->authenticationHandler->configure($request->options->auth, $request->headers);

                if ($authResult->headers !== $request->headers) {
                    $updatedRequest = $request->with(['headers' => $authResult->headers]);
                    $options = array_replace($options, $this->requestBuilder->buildOptions($updatedRequest));
                    unset($options[\App\Framework\HttpClient\Curl\HandleOption::PostFields->value]);
                    $options[\App\Framework\HttpClient\Curl\HandleOption::Upload->value] = true;
                    $options[\App\Framework\HttpClient\Curl\HandleOption::InFile->value] = $source;
                    if ($contentLength !== null) {
                        $options[\App\Framework\HttpClient\Curl\HandleOption::InFileSize->value] = $contentLength;
                    }
                }

                if (! empty($authResult->curlOptions)) {
                    $options = array_replace($options, $authResult->curlOptions);
                }
            }

            // Set all options
            $handle->setOptions($options);

            // Execute request (automatically uses CURLOPT_RETURNTRANSFER)
            $rawResponse = $handle->fetch();

            // Parse response
            return $this->responseParser->parse($rawResponse, $handle->getResource());
        } catch (\Throwable $e) {
            throw new CurlExecutionFailed($e->getMessage(), $e->getCode(), $e);
        }
    }


        /*
                // URL mit Query-Parametern verarbeiten
                $url = $request->url;
                if (!empty($request->options->query)) {
                    $separator = str_contains($url, '?') ? '&' : '?';
                    $url .= $separator . http_build_query($request->options->query);
                }

                $options = [
                    CURLOPT_URL => $url,
                    CURLOPT_CUSTOMREQUEST => $request->method->value,
                    CURLOPT_RETURNTRANSFER => true,
                    CURLOPT_HEADER => true,
                    CURLOPT_TIMEOUT => $request->options->timeout,
                    CURLOPT_CONNECTTIMEOUT => $request->options->connectTimeout,
                    CURLOPT_FOLLOWLOCATION => $request->options->followRedirects,
                    CURLOPT_MAXREDIRS => $request->options->maxRedirects,
                    CURLOPT_SSL_VERIFYPEER => $request->options->verifySsl,
                    CURLOPT_SSL_VERIFYHOST => $request->options->verifySsl ? 2 : 0,
                ];

                // User-Agent setzen wenn vorhanden
                if ($request->options->userAgent !== null) {
                    $options[CURLOPT_USERAGENT] = $request->options->userAgent;
                }

                // Proxy setzen wenn vorhanden
                if ($request->options->proxy !== null) {
                    $options[CURLOPT_PROXY] = $request->options->proxy;
                }

                // Authentifizierung einrichten
                if ($request->options->auth !== null) {
                    $this->setupAuthentication($ch, $request->options->auth, $request->headers);
                }

                // Request-Body verarbeiten
                if ($request->body !== '') {
                    $options[CURLOPT_POSTFIELDS] = $request->body;
                }

                // Headers formatieren und setzen
                if (count($request->headers->all()) > 0) {
                    $options[CURLOPT_HTTPHEADER] = HeaderManipulator::formatForCurl($request->headers);
                }

                curl_setopt_array($ch, $options);

                $raw = curl_exec($ch);

                if ($raw === false) {
                    throw new CurlExecutionFailed(curl_error($ch), curl_errno($ch));
                }

                $headerSize = curl_getinfo($ch, CURLINFO_HEADER_SIZE);
                $headersRaw = substr($raw, 0, $headerSize);
                $body = substr($raw, $headerSize);
                $status = curl_getinfo($ch, CURLINFO_HTTP_CODE);

                $headers = HeaderManipulator::fromString($headersRaw);

                return new ClientResponse(
                    status: Status::from($status),
                    headers: $headers,
                    body: $body
                );
    }
*/
}