<?php

namespace App\Services;

use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Str;
use RuntimeException;
use function imagecreatefromstring;
use function imagedestroy;
use function imagesx;
use function imagesy;
use function imagecreatetruecolor;
use function imagealphablending;
use function imagesavealpha;
use function imagecolorallocate;
use function imagefilledrectangle;
use function imagecopyresampled;
use function imagecopy;
use function imagejpeg;

class StoryImageNormalizerService
{
    public function __construct(private ?HuggingFaceMediaStorageService $hfMediaStorage = null)
    {
    }

    public function normalizeMany(array $sourceUrls): array
    {
        $variants = [];

        foreach ($sourceUrls as $sourceUrl) {
            if (! is_string($sourceUrl) || trim($sourceUrl) === '') {
                continue;
            }

            $variants[] = $this->normalizeVariant(trim($sourceUrl));
        }

        if ($variants === []) {
            throw new RuntimeException('Tidak ada image source yang bisa dinormalisasi ke format story.');
        }

        return $variants;
    }

    public function normalizeVariant(string $sourceUrl): array
    {
        if (! extension_loaded('gd')) {
            throw new RuntimeException('GD extension belum aktif, jadi normalisasi image story belum bisa dijalankan.');
        }

        $binary = $this->loadImageBinary($sourceUrl);
        $resource = @imagecreatefromstring($binary);

        if ($resource === false) {
            throw new RuntimeException('Gagal membaca image source untuk dinormalisasi ke story post.');
        }

        $storyCanvas = $this->renderCanvas($resource, 1080, 1920);
        $thumbCanvas = $this->renderCanvas($resource, 270, 480);
        imagedestroy($resource);

        $storyRelative = 'images/story_'.now()->format('Ymd_His').'_'.Str::lower(Str::random(8)).'.jpg';
        $thumbRelative = 'images/story_thumb_'.now()->format('Ymd_His').'_'.Str::lower(Str::random(8)).'.jpg';

        Storage::disk('public')->put($storyRelative, $this->jpegBinary($storyCanvas, 92));
        Storage::disk('public')->put($thumbRelative, $this->jpegBinary($thumbCanvas, 82));

        imagedestroy($storyCanvas);
        imagedestroy($thumbCanvas);

        return [
            'url' => $this->offloadPublicPath($storyRelative),
            'thumbnail_url' => $this->offloadPublicPath($thumbRelative),
            'width' => 1080,
            'height' => 1920,
        ];
    }

    private function offloadPublicPath(string $relativePath): string
    {
        try {
            return $this->hfMedia()->offloadPublicRelativePath($relativePath);
        } catch (\Throwable) {
            return Storage::url($relativePath);
        }
    }

    private function hfMedia(): HuggingFaceMediaStorageService
    {
        if ($this->hfMediaStorage instanceof HuggingFaceMediaStorageService) {
            return $this->hfMediaStorage;
        }

        $service = app(HuggingFaceMediaStorageService::class);
        if (! $service instanceof HuggingFaceMediaStorageService) {
            throw new RuntimeException('Service HuggingFaceMediaStorageService tidak tersedia.');
        }

        $this->hfMediaStorage = $service;

        return $this->hfMediaStorage;
    }

    private function renderCanvas($source, int $targetWidth, int $targetHeight)
    {
        $sourceWidth = imagesx($source);
        $sourceHeight = imagesy($source);

        $scale = max($targetWidth / max(1, $sourceWidth), $targetHeight / max(1, $sourceHeight));
        $resizedWidth = (int) ceil($sourceWidth * $scale);
        $resizedHeight = (int) ceil($sourceHeight * $scale);
        $offsetX = (int) floor(($resizedWidth - $targetWidth) / 2);
        $offsetY = (int) floor(($resizedHeight - $targetHeight) / 2);

        $resized = imagecreatetruecolor($resizedWidth, $resizedHeight);
        $canvas = imagecreatetruecolor($targetWidth, $targetHeight);

        if ($resized === false || $canvas === false) {
            throw new RuntimeException('Gagal menyiapkan canvas image story.');
        }

        imagealphablending($resized, true);
        imagesavealpha($resized, true);
        imagealphablending($canvas, true);
        imagesavealpha($canvas, true);

        $background = imagecolorallocate($resized, 11, 19, 31);
        imagefilledrectangle($resized, 0, 0, $resizedWidth, $resizedHeight, $background);
        imagecopyresampled($resized, $source, 0, 0, 0, 0, $resizedWidth, $resizedHeight, $sourceWidth, $sourceHeight);

        $canvasBg = imagecolorallocate($canvas, 11, 19, 31);
        imagefilledrectangle($canvas, 0, 0, $targetWidth, $targetHeight, $canvasBg);
        imagecopy($canvas, $resized, 0, 0, $offsetX, $offsetY, $targetWidth, $targetHeight);
        imagedestroy($resized);

        return $canvas;
    }

    private function jpegBinary($canvas, int $quality): string
    {
        ob_start();
        imagejpeg($canvas, null, $quality);
        $binary = ob_get_clean();

        if (! is_string($binary) || $binary === '') {
            throw new RuntimeException('Gagal mengekspor image story ke JPEG.');
        }

        return $binary;
    }

    private function loadImageBinary(string $imageUrl): string
    {
        $path = parse_url($imageUrl, PHP_URL_PATH) ?: $imageUrl;

        if (is_string($path) && str_starts_with($path, '/storage/')) {
            $relative = ltrim(substr($path, strlen('/storage/')), '/');
            if (Storage::disk('public')->exists($relative)) {
                $binary = Storage::disk('public')->get($relative);
                if ($binary !== '') {
                    return $binary;
                }
            }
        }

        $response = Http::timeout(90)->get($imageUrl);
        if (! $response->successful()) {
            throw new RuntimeException('Gagal mengambil image source untuk story post.');
        }

        return (string) $response->body();
    }
}