<?php

declare(strict_types=1);

namespace App\Services\Social;

use App\Enums\PostPlatform\ContentType;
use App\Enums\SocialAccount\Platform;
use App\Exceptions\Social\LinkedInPublishException;
use App\Exceptions\TokenExpiredException;
use App\Models\PostPlatform;
use App\Models\SocialAccount;
use App\Services\Media\MediaOptimizer;
use App\Services\Social\Concerns\HasSocialHttpClient;
use Illuminate\Http\Client\PendingRequest;
use Illuminate\Http\Client\Response;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

class LinkedInPublisher
{
    use HasSocialHttpClient;

    private string $baseUrl;

    private string $apiVersion = '202601';

    private string $accessToken;

    public function __construct()
    {
        $this->baseUrl = config('trypost.platforms.linkedin.api');
    }

    private SocialAccount $account;

    private bool $hasRetried = false;

    public function publish(PostPlatform $postPlatform): array
    {
        $this->validateContentLength($postPlatform);

        $content = $postPlatform->post->content ? app(ContentSanitizer::class)->sanitize($postPlatform->post->content, $postPlatform->platform) : null;

        $this->account = $postPlatform->socialAccount;
        $this->hasRetried = false;

        if ($this->account->is_token_expired || $this->account->is_token_expiring_soon) {
            app(ConnectionVerifier::class)->refreshToken($this->account);
        }

        $this->accessToken = $this->account->access_token;

        $personUrn = "urn:li:person:{$this->account->platform_user_id}";
        $contentType = $postPlatform->content_type;

        try {
            return match ($contentType) {
                ContentType::LinkedInCarousel => $this->publishCarousel($personUrn, $content, $postPlatform->post->mediaItems),
                ContentType::LinkedInPost => $this->publishPost($personUrn, $content, $postPlatform->post->mediaItems),
                default => throw new \Exception("Unsupported LinkedIn content type: {$contentType?->value}"),
            };
        } catch (TokenExpiredException $e) {
            return $this->retryWithRefresh($postPlatform, $content, $e);
        }
    }

    private function retryWithRefresh(PostPlatform $postPlatform, ?string $content, TokenExpiredException $originalException): array
    {
        if ($this->hasRetried) {
            throw $originalException;
        }

        $this->hasRetried = true;

        try {
            app(ConnectionVerifier::class)->refreshToken($this->account);
            $this->accessToken = $this->account->access_token;

            $personUrn = "urn:li:person:{$this->account->platform_user_id}";
            $contentType = $postPlatform->content_type;

            return match ($contentType) {
                ContentType::LinkedInCarousel => $this->publishCarousel($personUrn, $content, $postPlatform->post->mediaItems),
                ContentType::LinkedInPost => $this->publishPost($personUrn, $content, $postPlatform->post->mediaItems),
                default => throw new \Exception("Unsupported LinkedIn content type: {$contentType?->value}"),
            };
        } catch (\Throwable $e) {
            Log::error('LinkedIn refresh failed during retry', [
                'account_id' => $this->account->id,
                'error' => $e->getMessage(),
            ]);
            throw $originalException;
        }
    }

    private function publishPost(string $personUrn, ?string $content, $media): array
    {
        $payload = [
            'author' => $personUrn,
            'commentary' => $content ?? '',
            'visibility' => 'PUBLIC',
            'distribution' => [
                'feedDistribution' => 'MAIN_FEED',
                'targetEntities' => [],
                'thirdPartyDistributionChannels' => [],
            ],
            'lifecycleState' => 'PUBLISHED',
        ];

        if ($media->isNotEmpty()) {
            $firstMedia = $media->first();
            $mediaUrn = $this->uploadMedia($firstMedia, $personUrn);

            if ($mediaUrn) {
                $payload['content'] = [
                    'media' => [
                        'id' => $mediaUrn,
                    ],
                ];
            }
        }

        $response = $this->getHttpClient()
            ->post("{$this->baseUrl}/rest/posts", $payload);

        if ($response->failed()) {
            Log::error('LinkedIn post creation failed', [
                'status' => $response->status(),
                'body' => $this->redactResponseBody($response->body()),
            ]);
            $this->handleApiError($response);
        }

        $postId = $response->header('x-restli-id');

        return [
            'id' => $postId ?? 'unknown',
            'url' => $postId ? "https://www.linkedin.com/feed/update/{$postId}" : null,
        ];
    }

    private function publishCarousel(string $personUrn, ?string $content, $mediaCollection): array
    {
        // Upload images and build carousel items
        $carouselItems = [];

        foreach ($mediaCollection as $media) {
            if (! $media->isImage()) {
                continue;
            }

            $imageUrn = $this->uploadImage($media, $personUrn);

            if ($imageUrn) {
                $carouselItems[] = [
                    'altText' => $media->original_filename ?? 'Carousel image',
                    'media' => $imageUrn,
                ];
            }
        }

        if (empty($carouselItems)) {
            throw new \Exception('No valid images for LinkedIn carousel');
        }

        $payload = [
            'author' => $personUrn,
            'commentary' => $content ?? '',
            'visibility' => 'PUBLIC',
            'distribution' => [
                'feedDistribution' => 'MAIN_FEED',
                'targetEntities' => [],
                'thirdPartyDistributionChannels' => [],
            ],
            'lifecycleState' => 'PUBLISHED',
            'content' => [
                'multiImage' => [
                    'images' => $carouselItems,
                ],
            ],
        ];

        $response = $this->getHttpClient()
            ->post("{$this->baseUrl}/rest/posts", $payload);

        if ($response->failed()) {
            Log::error('LinkedIn carousel post creation failed', [
                'status' => $response->status(),
                'body' => $this->redactResponseBody($response->body()),
            ]);
            $this->handleApiError($response);
        }

        $postId = $response->header('x-restli-id');

        return [
            'id' => $postId ?? 'unknown',
            'url' => $postId ? "https://www.linkedin.com/feed/update/{$postId}" : null,
        ];
    }

    private function getHttpClient(): PendingRequest
    {
        return $this->socialHttp()->withToken($this->accessToken)
            ->withHeaders([
                'X-Restli-Protocol-Version' => '2.0.0',
                'LinkedIn-Version' => $this->apiVersion,
                'Content-Type' => 'application/json',
            ]);
    }

    private function uploadMedia($mediaItem, string $ownerUrn): ?string
    {
        $mimeType = $mediaItem->mime_type;
        $isVideo = str_starts_with($mimeType, 'video/');
        $isImage = str_starts_with($mimeType, 'image/');

        if ($isVideo) {
            return $this->uploadVideo($mediaItem, $ownerUrn);
        }

        if ($isImage) {
            return $this->uploadImage($mediaItem, $ownerUrn);
        }

        return null;
    }

    private function uploadImage($mediaItem, string $ownerUrn): ?string
    {
        // Step 1: Initialize upload
        $initResponse = $this->getHttpClient()
            ->post("{$this->baseUrl}/rest/images?action=initializeUpload", [
                'initializeUploadRequest' => [
                    'owner' => $ownerUrn,
                ],
            ]);

        if ($initResponse->failed()) {
            Log::error('LinkedIn image init failed', ['body' => $this->redactResponseBody($initResponse->body())]);
            $this->handleApiError($initResponse);
        }

        $initData = $initResponse->json();
        $uploadUrl = $initData['value']['uploadUrl'] ?? null;
        $imageUrn = $initData['value']['image'] ?? null;

        if (! $uploadUrl || ! $imageUrn) {
            throw new \Exception('LinkedIn image upload init missing uploadUrl or image URN');
        }

        // Step 2: Download and optimize image
        $tempFile = tempnam(sys_get_temp_dir(), 'li_image_');

        try {
            $downloadResponse = Http::withOptions(['sink' => $tempFile])->timeout(600)->get($mediaItem->url);

            if ($downloadResponse->failed()) {
                throw new \Exception('Failed to download media: HTTP '.$downloadResponse->status());
            }

            $detectedMime = mime_content_type($tempFile) ?: '';
            if (str_starts_with($detectedMime, 'image/') && ! str_starts_with($detectedMime, 'image/gif')) {
                $optimizer = app(MediaOptimizer::class);
                $optimizedPath = $optimizer->optimizeImage($tempFile, Platform::LinkedIn);
                @unlink($tempFile);
                $tempFile = $optimizedPath;
            }

            $stream = fopen($tempFile, 'r');

            $uploadResponse = Http::withToken($this->accessToken)
                ->withHeaders([
                    'Content-Type' => 'application/octet-stream',
                ])
                ->withBody($stream, 'application/octet-stream')
                ->put($uploadUrl);

            if (is_resource($stream)) {
                fclose($stream);
            }

            if ($uploadResponse->failed()) {
                Log::error('LinkedIn image upload failed', ['body' => $this->redactResponseBody($uploadResponse->body())]);
                $this->handleApiError($uploadResponse);
            }

            return $imageUrn;
        } finally {
            @unlink($tempFile);
        }
    }

    private function uploadVideo($mediaItem, string $ownerUrn): ?string
    {
        $tempFile = tempnam(sys_get_temp_dir(), 'li_video_');

        try {
            return $this->doUploadVideo($tempFile, $mediaItem, $ownerUrn);
        } finally {
            @unlink($tempFile);
        }
    }

    private function doUploadVideo(string $tempFile, $mediaItem, string $ownerUrn): ?string
    {
        $downloadResponse = Http::withOptions(['sink' => $tempFile])->timeout(600)->get($mediaItem->url);

        if ($downloadResponse->failed()) {
            throw new \Exception('Failed to download media: HTTP '.$downloadResponse->status());
        }

        $fileSize = (int) filesize($tempFile);

        // Step 1: Initialize upload
        $initResponse = $this->getHttpClient()
            ->post("{$this->baseUrl}/rest/videos?action=initializeUpload", [
                'initializeUploadRequest' => [
                    'owner' => $ownerUrn,
                    'fileSizeBytes' => $fileSize,
                    'uploadCaptions' => false,
                    'uploadThumbnail' => false,
                ],
            ]);

        if ($initResponse->failed()) {
            Log::error('LinkedIn video init failed', ['body' => $this->redactResponseBody($initResponse->body())]);
            $this->handleApiError($initResponse);
        }

        $initData = $initResponse->json();
        $videoUrn = $initData['value']['video'] ?? null;
        $uploadInstructions = $initData['value']['uploadInstructions'] ?? [];
        $uploadToken = $initData['value']['uploadToken'] ?? '';

        if (! $videoUrn || empty($uploadInstructions)) {
            throw new \Exception('LinkedIn video upload init missing video URN or upload instructions');
        }

        // Step 2: Upload chunks
        $uploadedPartIds = [];
        $handle = fopen($tempFile, 'r');

        try {
            foreach ($uploadInstructions as $index => $instruction) {
                $uploadUrl = data_get($instruction, 'uploadUrl');
                $firstByte = data_get($instruction, 'firstByte');
                $lastByte = data_get($instruction, 'lastByte');

                $chunkLength = $lastByte - $firstByte + 1;
                fseek($handle, $firstByte);
                $chunkData = fread($handle, $chunkLength);

                $chunkResponse = Http::withToken($this->accessToken)
                    ->withHeaders([
                        'Content-Type' => 'application/octet-stream',
                    ])
                    ->timeout(600)
                    ->withBody($chunkData, 'application/octet-stream')
                    ->put($uploadUrl);

                if ($chunkResponse->failed()) {
                    Log::error('LinkedIn video chunk upload failed', [
                        'index' => $index,
                        'body' => $this->redactResponseBody($chunkResponse->body()),
                    ]);
                    $this->handleApiError($chunkResponse);
                }

                $etag = $chunkResponse->header('etag');
                if ($etag) {
                    $uploadedPartIds[] = $etag;
                }

            }
        } finally {
            fclose($handle);
        }

        // Step 3: Finalize upload
        $finalizeResponse = $this->getHttpClient()
            ->post("{$this->baseUrl}/rest/videos?action=finalizeUpload", [
                'finalizeUploadRequest' => [
                    'video' => $videoUrn,
                    'uploadToken' => $uploadToken,
                    'uploadedPartIds' => $uploadedPartIds,
                ],
            ]);

        if ($finalizeResponse->failed()) {
            Log::error('LinkedIn video finalize failed', ['body' => $this->redactResponseBody($finalizeResponse->body())]);
            $this->handleApiError($finalizeResponse);
        }

        // Step 4: Wait for processing
        $this->waitForVideoProcessing($videoUrn);

        return $videoUrn;
    }

    private function waitForVideoProcessing(string $videoUrn, int $maxAttempts = 30): void
    {
        $encodedUrn = urlencode($videoUrn);

        for ($i = 0; $i < $maxAttempts; $i++) {
            $response = $this->getHttpClient()
                ->get("{$this->baseUrl}/rest/videos/{$encodedUrn}");

            if ($response->failed()) {
                Log::warning('LinkedIn video status check failed', ['attempt' => $i]);
                sleep(5);

                continue;
            }

            $data = $response->json();
            $status = data_get($data, 'status', 'UNKNOWN');

            if ($status === 'AVAILABLE') {
                return;
            }

            if ($status === 'PROCESSING_FAILED') {
                throw new \Exception('LinkedIn video processing failed');
            }

            sleep(5);
        }

        Log::warning('LinkedIn video processing timeout, proceeding anyway');
    }

    private function handleApiError(Response $response): never
    {
        throw LinkedInPublishException::fromApiResponse($response);
    }
}