<?php

namespace App\Services;

use Illuminate\Http\Client\Response;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Str;
use RuntimeException;

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

    public function generate(string $prompt, int $duration = 5): array
    {
        $apiKey = trim((string) config('services.freepik.api_key', ''));
        $timeout = max(20, (int) config('services.freepik.timeout', 90));
        $cleanPrompt = trim($prompt);
        $duration = in_array($duration, [5, 8, 10], true) ? $duration : 5;

        if ($apiKey === '') {
            throw new RuntimeException($this->missingApiKeyMessage('Video generator'));
        }

        if ($cleanPrompt === '') {
            throw new RuntimeException('Prompt video Freepik tidak boleh kosong.');
        }

        $response = $this->client($apiKey, $timeout)
            ->post($this->videoEndpoint(), [
                'prompt' => $cleanPrompt,
                'ratio' => '720:1280',
                'duration' => $duration,
            ]);

        $data = $this->extractData($response, 'Freepik video request gagal');
        $videoUrl = $this->extractGeneratedUrl($data);

        if ($videoUrl === null) {
            $taskId = trim((string) data_get($data, 'task_id', ''));
            if ($taskId === '') {
                throw new RuntimeException('Freepik video tidak mengembalikan task_id.');
            }

            $videoUrl = $this->awaitGeneratedUrl($apiKey, $timeout, $taskId);
        }

        $relativePath = $this->persistVideo($videoUrl, $timeout);

        return [
            'url' => $this->offloadPublicPath($relativePath),
            'provider' => 'freepik-runway',
            'aspect' => '9:16',
            'duration_seconds' => $duration,
        ];
    }

    private function awaitGeneratedUrl(string $apiKey, int $timeout, string $taskId): string
    {
        $deadline = microtime(true) + max(35, min(240, $timeout * 2));
        $lastError = null;

        do {
            try {
                $response = $this->client($apiKey, min(25, $timeout))
                    ->get($this->videoEndpoint().'/'.$taskId);

                $data = $this->extractData($response, 'Gagal membaca status task Freepik video');
                $generatedUrl = $this->extractGeneratedUrl($data);

                if ($generatedUrl !== null) {
                    return $generatedUrl;
                }

                $status = strtoupper(trim((string) data_get($data, 'status', '')));
                if (in_array($status, ['FAILED', 'ERROR', 'REJECTED', 'CANCELLED'], true)) {
                    throw new RuntimeException('Freepik video task berakhir dengan status '.$status.'.');
                }
            } catch (\Throwable $pollError) {
                $lastError = $pollError;
            }

            usleep(1500000);
        } while (microtime(true) < $deadline);

        if ($lastError !== null) {
            throw new RuntimeException('Timeout saat menunggu hasil video dari Freepik. Detail terakhir: '.$lastError->getMessage());
        }

        throw new RuntimeException('Timeout saat menunggu hasil video dari Freepik.');
    }

    private function persistVideo(string $videoUrl, int $timeout): string
    {
        $response = Http::connectTimeout(20)
            ->timeout(max(45, min(120, $timeout * 2)))
            ->withHeaders(['Accept' => 'video/*'])
            ->get($videoUrl);

        if (! $response->successful()) {
            throw new RuntimeException('Gagal mengambil hasil video dari Freepik: '.$response->status());
        }

        $binary = $response->body();
        if (! is_string($binary) || $binary === '') {
            throw new RuntimeException('Binary video dari Freepik kosong.');
        }

        $relativePath = 'videos/freepik_'.now()->format('Ymd_His').'_'.Str::lower(Str::random(8)).'.mp4';
        Storage::disk('public')->makeDirectory('videos');

        if (! Storage::disk('public')->put($relativePath, $binary)) {
            throw new RuntimeException('Gagal menyimpan hasil video Freepik ke storage public.');
        }

        return $relativePath;
    }

    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 client(string $apiKey, int $timeout)
    {
        return Http::connectTimeout(20)
            ->timeout($timeout)
            ->acceptJson()
            ->withHeaders([
                'x-freepik-api-key' => $apiKey,
            ]);
    }

    /**
     * Build the Freepik video generation endpoint.
     *
     * The original implementation concatenated the configured `services.freepik.base_url`
     * (which defaults to the *text‑to‑image* endpoint) with the video path, resulting in
     * an invalid URL such as `https://api.freepik.com/v1/ai/text-to-image/v1/ai/text-to-video/...`.
     * This caused the remote API to return a 500 error which propagated to the Space UI.
     *
     * The logic now:
     *   1. If the user explicitly sets a `FREEPIK_VIDEO_BASE_URL` env variable (via the config
     *      key `services.freepik.video_base_url` – fallback to the generic `base_url`), use it
     *      directly.
     *   2. If the configured base URL already contains the segment `text-to-video`, assume it
     *      is a proper video endpoint and return it unchanged.
     *   3. Otherwise fall back to the official default video endpoint.
     */
    private function videoEndpoint(): string
    {
        // Allow an explicit video base URL; otherwise reuse the generic base_url.
        $configured = trim((string) config('services.freepik.video_base_url', config('services.freepik.base_url', '')));

        if ($configured === '' || Str::contains($configured, 'text-to-video')) {
            // Empty config or already a video endpoint – use the default video URL.
            return $configured !== '' && Str::contains($configured, 'text-to-video')
                ? rtrim($configured, '/').'/runway-4-5'
                : 'https://api.freepik.com/v1/ai/text-to-video/runway-4-5';
        }

        // If a non‑video base URL is provided (e.g., the default text‑to‑image URL), ignore it
        // and return the canonical video endpoint.
        return 'https://api.freepik.com/v1/ai/text-to-video/runway-4-5';
    }

    private function apiOrigin(string $url): string
    {
        $scheme = parse_url($url, PHP_URL_SCHEME) ?: 'https';
        $host = parse_url($url, PHP_URL_HOST);
        $port = parse_url($url, PHP_URL_PORT);

        if (! is_string($host) || $host === '') {
            return 'https://api.freepik.com';
        }

        return $scheme.'://'.$host.($port ? ':'.$port : '');
    }

    private function extractData(Response $response, string $prefix): array
    {
        if (! $response->successful()) {
            throw new RuntimeException($prefix.': '.$response->status().' - '.$this->responseError($response));
        }

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

        if (! is_array($data)) {
            throw new RuntimeException($prefix.': format response Freepik tidak dikenali.');
        }

        return $data;
    }

    private function responseError(Response $response): string
    {
        $message = data_get($response->json(), 'message')
            ?? data_get($response->json(), 'error.message')
            ?? data_get($response->json(), 'detail')
            ?? $response->body();

        return Str::limit(trim((string) $message), 240);
    }

    /**
     * Return a helpful message when the Freepik API key is missing.
     *
     * In a Hugging Face Space the environment variables are defined in the Space
     * settings.  If the key is absent we guide the user to add
     * `FREEPIK_API_KEY` there.  When the space runs in HF‑only mode we explain
     * that the video feature is disabled.
     */
    private function missingApiKeyMessage(string $feature): string
    {
        $hfOnly = strtolower(trim((string) (
            config('services.huggingface.hf_only')
            ?? $_ENV['TOOLS_HF_ONLY']
            ?? $_SERVER['TOOLS_HF_ONLY']
            ?? getenv('TOOLS_HF_ONLY')
            ?? 'false'
        )));

        if (in_array($hfOnly, ['1', 'true', 'yes', 'on'], true)) {
            return $feature.' belum tersedia di mode Hugging Face‑only.';
        }

        return 'FREEPIK_API_KEY belum diisi di file .env. Tambahkan variabel `FREEPIK_API_KEY` di Settings → Secrets of the Hugging Face Space dan redeploy.';
    }

    private function extractGeneratedUrl(array $data): ?string
    {
        $candidates = data_get($data, 'generated', []);

        if (! is_array($candidates) || $candidates === []) {
            return null;
        }

        foreach ($candidates as $candidate) {
            if (is_string($candidate) && Str::startsWith($candidate, ['http://', 'https://'])) {
                return trim($candidate);
            }

            if (is_array($candidate)) {
                $url = data_get($candidate, 'url', data_get($candidate, 'video_url'));
                if (is_string($url) && trim($url) !== '') {
                    return trim($url);
                }
            }
        }

        return null;
    }
}