<?php

namespace app\api\controller;

use app\common\controller\Api;
use app\job\SeedreamImageGenerationJob;
use OSS\OssClient;
use think\Config;
use think\Log;
use think\Queue;

/**
 * 文生图 / 图生图 / 组图生组图（豆包 Seedream）
 */
class ImageGeneration extends Api
{
    protected $noNeedLogin = ['*'];
    protected $noNeedRight = ['*'];

    const DEFAULT_MODEL = 'doubao-seedream-5-0-260128';
    const DEFAULT_API_URL = 'https://ark.cn-beijing.volces.com/api/v3/images/generations';

    /**
     * 文生图 / 图生图 / 组图生组图
     * POST /api/image_generation/generate
     *
     * 参数：
     * - prompt（必填）提示词
     * - image / images / image_url / image_urls / reference_images（可选）参考图，支持字符串或数组，最多 14 张
     * - 上传 image / images 文件（可选，支持多文件；先上传 OSS，再以 OSS URL 作为参考图）
     * - max_images / generate_count / output_count 生成张数，默认 1；大于 1 时走异步队列（seedreamimage）
     * - model 模型，默认 doubao-seedream-5-0-260128
     * - size 尺寸，默认 2K
     * - sequential_image_generation 组图模式，不传时：生成 1 张为 disabled，多张为 auto
     * - stream 是否流式，默认 false（组图队列任务固定非流式）
     * - watermark 是否加水印，默认 false
     *
     * 组图（max_images>1）返回 task_id，请轮询 getStatus 接口获取结果
     *
     * 模式说明（由参考图数量 + 生成数量自动判定）：
     * - 0 张参考 + 1 张输出 → text_to_image 文生单图
     * - 0 张参考 + N 张输出 → text_to_images 文生组图
     * - 1 张参考 + 1 张输出 → image_to_image 单图生单图
     * - 1 张参考 + N 张输出 → image_to_images 单图生组图
     * - M 张参考 + N 张输出 → images_to_images 组图生组图
     *
     * AI 调用成功后会写入 picture_storage（img_id、prompt、reference_img_url 等；generate_img_url 暂不写入）
     */
    public function generate()
    {
        set_time_limit(600);
        ini_set('max_execution_time', '600');

        try {
            $params = $this->mergeRequestParams();

            $prompt = trim((string)($params['prompt'] ?? ''));
            if ($prompt === '') {
                return json(['code' => 0, 'msg' => 'prompt 不能为空']);
            }

            $referenceImages = $this->resolveReferenceImages($params);
            $referenceCount = count($referenceImages);
            $genConfig = $this->buildGenerationConfig($params, $referenceCount);

            $model = trim((string)($params['model'] ?? self::DEFAULT_MODEL));
            $stream = filter_var($params['stream'] ?? false, FILTER_VALIDATE_BOOLEAN);
            $watermark = filter_var($params['watermark'] ?? false, FILTER_VALIDATE_BOOLEAN);
            $size = trim((string)($params['size'] ?? '2K'));

            $requestBody = [
                'model' => $model,
                'prompt' => $prompt,
                'sequential_image_generation' => $genConfig['sequential_image_generation'],
                'response_format' => 'url',
                'size' => $size,
                'stream' => $stream,
                'watermark' => $watermark,
            ];
            if ($genConfig['sequential_image_generation'] !== 'disabled') {
                $requestBody['sequential_image_generation_options'] = [
                    'max_images' => $genConfig['max_images'],
                ];
            }
            if ($referenceCount > 0) {
                $requestBody['image'] = $referenceCount === 1 ? $referenceImages[0] : $referenceImages;
            }

            $taskPayload = [
                'prompt' => $prompt,
                'model' => $model,
                'size' => $size,
                'watermark' => $watermark,
                'stream' => $stream,
                'reference_images' => $referenceImages,
                'gen_config' => $genConfig,
                'request_body' => $requestBody,
            ];

            if ($genConfig['max_images'] > 1) {
                return $this->submitBatchTask($taskPayload, $genConfig, $referenceImages, $referenceCount);
            }

            $payload = SeedreamImageGenerationJob::execute($taskPayload);
            $dbError = (string)($payload['db_save_error'] ?? '');
            unset($payload['db_save_error']);

            return $this->jsonGenerateSuccess($payload, $dbError);
        } catch (\Exception $e) {
            $this->logError('[ImageGeneration/generate] ' . $e->getMessage());
            return json(['code' => 0, 'msg' => $e->getMessage()]);
        }
    }

    /**
     * 查询组图异步任务状态
     * GET/POST /api/image_generation/getStatus
     * 参数：task_id
     */
    public function getStatus()
    {
        $taskId = trim((string)$this->request->param('task_id', ''));
        if ($taskId === '') {
            return json(['code' => 0, 'msg' => 'task_id 不能为空']);
        }

        $redis = getTaskRedis();
        $raw = $redis->get(SeedreamImageGenerationJob::REDIS_KEY_PREFIX . $taskId);
        if (!$raw) {
            return json(['code' => 0, 'msg' => '任务不存在或已过期']);
        }

        $info = json_decode($raw, true);
        if (!is_array($info)) {
            return json(['code' => 0, 'msg' => '任务数据异常']);
        }

        return json([
            'code' => 1,
            'msg' => '查询成功',
            'data' => $info,
        ]);
    }

    /**
     * 组图任务提交到独立队列 seedreamimage
     */
    private function submitBatchTask(
        array $taskPayload,
        array $genConfig,
        array $referenceImages,
        int $referenceCount
    ): \think\response\Json {
        $taskId = 'sd' . date('YmdHis') . mt_rand(1000, 9999);
        $taskPayload['task_id'] = $taskId;
        $taskPayload['stream'] = false;

        $redis = getTaskRedis();
        $redis->set(
            SeedreamImageGenerationJob::REDIS_KEY_PREFIX . $taskId,
            json_encode([
                'status' => 'pending',
                'task_id' => $taskId,
                'mode' => $genConfig['mode'],
                'reference_count' => $referenceCount,
                'reference_images' => $referenceImages,
                'max_images' => $genConfig['max_images'],
                'created_at' => date('Y-m-d H:i:s'),
            ], JSON_UNESCAPED_UNICODE),
            ['EX' => SeedreamImageGenerationJob::TASK_TTL]
        );

        Queue::push('app\job\SeedreamImageGenerationJob', $taskPayload, SeedreamImageGenerationJob::QUEUE_NAME);

        return json([
            'code' => 1,
            'msg' => '组图任务已提交，请稍后查询结果',
            'data' => [
                'async' => true,
                'task_id' => $taskId,
                'status' => 'pending',
                'mode' => $genConfig['mode'],
                'reference_count' => $referenceCount,
                'reference_images' => $referenceImages,
                'max_images' => $genConfig['max_images'],
                'poll_url' => '/api/image_generation/getStatus',
            ],
        ]);
    }

    /**
     * AI 成功但数据库失败时，仍返回生成结果并附带警告
     */
    private function jsonGenerateSuccess(array $payload, string $dbError = ''): \think\response\Json
    {
        if ($dbError !== '') {
            $payload['db_save_error'] = $dbError;
        }
        return json([
            'code' => 1,
            'msg' => $dbError !== '' ? '生成成功，但数据库保存失败' : '生成成功',
            'data' => $payload,
        ]);
    }

    /**
     * 根据前端参数构建组图配置
     */
    private function buildGenerationConfig(array $params, int $referenceCount): array
    {
        $maxImages = (int)($params['max_images'] ?? $params['generate_count'] ?? $params['output_count'] ?? 1);
        $maxImages = max(1, min(15, $maxImages));

        $sequentialMode = trim((string)($params['sequential_image_generation'] ?? ''));
        if ($sequentialMode === '') {
            $sequentialMode = $maxImages > 1 ? 'auto' : 'disabled';
        }

        return [
            'max_images' => $maxImages,
            'sequential_image_generation' => $sequentialMode,
            'mode' => $this->detectGenerationMode($referenceCount, $maxImages),
        ];
    }

    /**
     * 判定当前生成模式
     */
    private function detectGenerationMode(int $referenceCount, int $maxImages): string
    {
        if ($referenceCount === 0) {
            return $maxImages > 1 ? 'text_to_images' : 'text_to_image';
        }
        if ($referenceCount === 1) {
            return $maxImages > 1 ? 'image_to_images' : 'image_to_image';
        }
        return $maxImages > 1 ? 'images_to_images' : 'images_to_image';
    }

    /**
     * 解析参考图列表：上传文件/base64 先落 OSS，再以公网 URL 传给 AI
     * @return string[]
     */
    private function resolveReferenceImages(array $params): array
    {
        $resolved = [];

        foreach (['image', 'images'] as $field) {
            $uploaded = $this->request->file($field);
            if (empty($uploaded)) {
                continue;
            }
            $fileList = is_array($uploaded) ? $uploaded : [$uploaded];
            foreach ($fileList as $file) {
                if (!$file) {
                    continue;
                }
                $ossUrl = $this->uploadUploadedFileToOss($file);
                if ($ossUrl !== '') {
                    $resolved[] = $ossUrl;
                }
            }
        }

        $rawList = [];
        foreach (['images', 'reference_images', 'image_urls'] as $key) {
            if (empty($params[$key]) || !is_array($params[$key])) {
                continue;
            }
            foreach ($params[$key] as $item) {
                if ($item !== null && $item !== '') {
                    $rawList[] = $item;
                }
            }
        }
        foreach (['image', 'image_url'] as $key) {
            if (empty($params[$key])) {
                continue;
            }
            if (is_array($params[$key])) {
                foreach ($params[$key] as $item) {
                    if ($item !== null && $item !== '') {
                        $rawList[] = $item;
                    }
                }
            } else {
                $rawList[] = $params[$key];
            }
        }

        foreach ($rawList as $raw) {
            $item = $this->resolveSingleReferenceImage((string)$raw);
            if ($item !== '') {
                $resolved[] = $item;
            }
        }

        return array_slice($resolved, 0, 14);
    }

    /**
     * 解析单张参考图（URL/路径直接使用；base64 先上传 OSS）
     */
    private function resolveSingleReferenceImage(string $raw): string
    {
        $raw = trim($raw);
        if ($raw === '') {
            return '';
        }

        if (stripos($raw, 'data:image/') === 0) {
            return $this->uploadBase64ImageToOss($raw);
        }

        if (stripos($raw, 'http://') === 0 || stripos($raw, 'https://') === 0) {
            return $raw;
        }

        if (preg_match('/^[A-Za-z0-9+\/=\s]+$/', $raw) && strlen($raw) > 100) {
            $ossUrl = $this->uploadBase64ImageToOss($raw);
            if ($ossUrl !== '') {
                return $ossUrl;
            }
        }

        $normalizedPath = ltrim(str_replace('\\', '/', $raw), '/');
        $publicUrl = $this->buildOssPublicUrl($normalizedPath);
        if (stripos($publicUrl, 'http://') === 0 || stripos($publicUrl, 'https://') === 0) {
            return $publicUrl;
        }

        $localPath = ROOT_PATH . 'public' . DIRECTORY_SEPARATOR . str_replace('/', DIRECTORY_SEPARATOR, $normalizedPath);
        if (is_file($localPath)) {
            return $this->uploadLocalFileToOss($localPath, $normalizedPath);
        }

        try {
            $loaded = $this->readImageBinary($raw);
            $dataUrl = 'data:' . $loaded['mimeType'] . ';base64,' . $loaded['base64Data'];
            return $this->uploadBase64ImageToOss($dataUrl);
        } catch (\Exception $e) {
            $this->logWarning('[ImageGeneration] 读取参考图失败: ' . $e->getMessage());
            return '';
        }
    }

    /**
     * form-data 上传文件：落盘 → OSS → 返回公网 URL
     */
    private function uploadUploadedFileToOss($file): string
    {
        if (!$this->isOssEnabled()) {
            throw new \Exception('OSS 未配置，无法上传参考图');
        }

        $ext = $this->resolveUploadedImageExt($file);
        if ($ext === '') {
            throw new \Exception('不支持的图片格式');
        }

        $dateDir = date('Ymd');
        $saveDir = ROOT_PATH . 'public' . DIRECTORY_SEPARATOR . 'uploads' . DIRECTORY_SEPARATOR . 'imagegen' . DIRECTORY_SEPARATOR . $dateDir . DIRECTORY_SEPARATOR;
        if (!is_dir($saveDir)) {
            mkdir($saveDir, 0755, true);
        }

        $fileName = 'ref_' . str_replace('.', '', uniqid('', true)) . '.' . $ext;
        $localFullPath = $saveDir . $fileName;
        $saved = false;

        if (method_exists($file, 'isValid') && $file->isValid()) {
            $info = $file->move($saveDir, $fileName);
            if ($info) {
                $localFullPath = $saveDir . $info->getFilename();
                $saved = true;
            }
        }
        if (!$saved) {
            $uploadInfo = $file->getInfo();
            $tmpPath = isset($uploadInfo['tmp_name']) ? (string)$uploadInfo['tmp_name'] : '';
            if ($tmpPath === '' || !is_file($tmpPath)) {
                $tmpPath = (string)($file->getRealPath() ?: '');
            }
            if ($tmpPath === '' || !is_file($tmpPath) || !@copy($tmpPath, $localFullPath)) {
                throw new \Exception('参考图保存失败');
            }
        }

        $objectKey = 'uploads/imagegen/' . $dateDir . '/' . basename($localFullPath);
        return $this->uploadLocalFileToOss($localFullPath, $objectKey);
    }

    /**
     * base64 图片：落盘 → OSS → 返回公网 URL
     */
    private function uploadBase64ImageToOss(string $base64Input): string
    {
        if (!$this->isOssEnabled()) {
            throw new \Exception('OSS 未配置，无法上传参考图');
        }

        $parsed = $this->parseBase64Image($base64Input);
        if ($parsed === null) {
            return '';
        }

        [$ext, $imageData] = $parsed;
        $dateDir = date('Ymd');
        $saveDir = ROOT_PATH . 'public' . DIRECTORY_SEPARATOR . 'uploads' . DIRECTORY_SEPARATOR . 'imagegen' . DIRECTORY_SEPARATOR . $dateDir . DIRECTORY_SEPARATOR;
        if (!is_dir($saveDir)) {
            mkdir($saveDir, 0755, true);
        }

        $fileName = 'ref_' . str_replace('.', '', uniqid('', true)) . '.' . $ext;
        $localFullPath = $saveDir . $fileName;
        if (file_put_contents($localFullPath, $imageData) === false) {
            throw new \Exception('参考图本地保存失败');
        }

        $objectKey = 'uploads/imagegen/' . $dateDir . '/' . $fileName;
        return $this->uploadLocalFileToOss($localFullPath, $objectKey);
    }

    /**
     * 本地文件上传 OSS 并返回公网 URL
     */
    private function uploadLocalFileToOss(string $localFullPath, string $objectKey): string
    {
        $objectKey = $this->normalizeOssObjectKey($objectKey);
        if (!$this->putFileToOss($localFullPath, $objectKey)) {
            throw new \Exception('参考图上传 OSS 失败');
        }

        $url = $this->buildOssPublicUrl($objectKey);
        if (stripos($url, 'http://') !== 0 && stripos($url, 'https://') !== 0) {
            throw new \Exception('无法获取参考图 OSS 访问地址，请检查 oss.host 配置');
        }

        return $url;
    }

    /**
     * 解析 base64 图片
     * @return array{0:string,1:string}|null [扩展名, 二进制内容]
     */
    private function parseBase64Image(string $base64Input): ?array
    {
        $base64Input = trim($base64Input);
        if ($base64Input === '') {
            return null;
        }

        $ext = 'jpg';
        $rawBase64 = $base64Input;
        $prefix = 'data:image/';
        if (stripos($base64Input, $prefix) === 0) {
            $semi = stripos($base64Input, ';base64,');
            if ($semi === false) {
                return null;
            }
            $mimePart = strtolower(substr($base64Input, strlen($prefix), $semi - strlen($prefix)));
            if ($mimePart === 'jpeg') {
                $mimePart = 'jpg';
            }
            if (in_array($mimePart, ['jpg', 'png', 'gif', 'webp', 'bmp'], true)) {
                $ext = $mimePart;
            }
            $rawBase64 = substr($base64Input, $semi + 8);
        }

        $rawBase64 = preg_replace('/\s+/', '', $rawBase64);
        if ($rawBase64 === '') {
            return null;
        }

        $imageData = base64_decode($rawBase64, true);
        if ($imageData === false || strlen($imageData) < 100) {
            return null;
        }

        return [$ext, $imageData];
    }

    /**
     * 解析上传图片扩展名
     */
    private function resolveUploadedImageExt($file): string
    {
        $name = $file->getInfo('name') ?? '';
        $ext = strtolower(pathinfo($name, PATHINFO_EXTENSION));
        if ($ext === 'jpeg') {
            $ext = 'jpg';
        }
        $allowed = ['jpg', 'png', 'gif', 'webp', 'bmp'];
        if ($ext && in_array($ext, $allowed, true)) {
            return $ext;
        }

        $mime = method_exists($file, 'getMime') ? strtolower((string)$file->getMime()) : '';
        $map = [
            'image/jpeg' => 'jpg',
            'image/png' => 'png',
            'image/gif' => 'gif',
            'image/webp' => 'webp',
            'image/bmp' => 'bmp',
        ];

        return $map[$mime] ?? '';
    }

    /**
     * 读取图片二进制（本地路径 / 完整 URL / OSS 相对路径）
     * @return array{base64Data:string,mimeType:string}
     */
    private function readImageBinary(string $imageUrl): array
    {
        $imageUrl = trim($imageUrl);
        if ($imageUrl === '') {
            throw new \Exception('图片路径不能为空');
        }

        $rootPath = str_replace('\\', '/', ROOT_PATH);
        $relativePath = ltrim($imageUrl, '/');
        $localPath = rtrim($rootPath, '/') . '/public/' . $relativePath;
        $localPathDecoded = rtrim($rootPath, '/') . '/public/' . urldecode($relativePath);

        $imageContent = false;
        $mimeType = '';

        if (preg_match('/^https?:\/\//i', $imageUrl)) {
            $imageContent = @file_get_contents($imageUrl);
        } elseif (file_exists($localPath)) {
            $imageContent = @file_get_contents($localPath);
            if ($imageContent !== false) {
                $finfo = finfo_open(FILEINFO_MIME_TYPE);
                $mimeType = finfo_file($finfo, $localPath);
                finfo_close($finfo);
            }
        } elseif (file_exists($localPathDecoded)) {
            $imageContent = @file_get_contents($localPathDecoded);
            if ($imageContent !== false) {
                $finfo = finfo_open(FILEINFO_MIME_TYPE);
                $mimeType = finfo_file($finfo, $localPathDecoded);
                finfo_close($finfo);
            }
        } else {
            $ossConfig = $this->getOssConfig();
            $ossHost = trim((string)($ossConfig['host'] ?? ''));
            if ($ossHost !== '') {
                if (stripos($ossHost, 'http://') !== 0 && stripos($ossHost, 'https://') !== 0) {
                    $ossHost = 'https://' . $ossHost;
                }
                $remoteUrl = rtrim($ossHost, '/') . '/' . ltrim($relativePath, '/');
                $imageContent = @file_get_contents($remoteUrl);
            }
        }

        if ($imageContent === false || $imageContent === '') {
            throw new \Exception('图片内容读取失败（本地/OSS均未读取到）');
        }

        if ($mimeType === '') {
            $finfo = finfo_open(FILEINFO_MIME_TYPE);
            $mimeType = finfo_buffer($finfo, $imageContent);
            finfo_close($finfo);
        }
        if (!$mimeType) {
            $mimeType = 'image/png';
        }

        return [
            'base64Data' => base64_encode($imageContent),
            'mimeType' => $mimeType,
        ];
    }

    /**
     * 获取 OSS 配置
     */
    private function getOssConfig(): array
    {
        $config = Config::get('oss');
        return is_array($config) ? $config : [];
    }

    /**
     * OSS 是否可用
     */
    private function isOssEnabled(): bool
    {
        $config = $this->getOssConfig();
        return !empty($config['accessKeyId'])
            && !empty($config['accessKeySecret'])
            && !empty($config['endpoint'])
            && !empty($config['bucket']);
    }

    /**
     * 归一化 OSS 对象键
     */
    private function normalizeOssObjectKey(string $objectKey): string
    {
        return ltrim(str_replace('\\', '/', trim($objectKey)), '/');
    }

    /**
     * 上传本地文件到 OSS
     */
    private function putFileToOss(string $localFullPath, string $objectKey): bool
    {
        if (!$this->isOssEnabled() || !is_file($localFullPath)) {
            return false;
        }

        $config = $this->getOssConfig();
        $objectKey = $this->normalizeOssObjectKey($objectKey);
        if ($objectKey === '') {
            return false;
        }

        try {
            $ossClient = new OssClient(
                $config['accessKeyId'],
                $config['accessKeySecret'],
                $config['endpoint']
            );
            $ossClient->uploadFile($config['bucket'], $objectKey, $localFullPath);
            return true;
        } catch (\Throwable $e) {
            $this->logError('[ImageGeneration/OSS] ' . $e->getMessage() . ' | objectKey=' . $objectKey);
            return false;
        }
    }

    /**
     * 相对路径转 OSS 公网 URL
     */
    private function buildOssPublicUrl(string $path): string
    {
        $path = trim($path);
        if ($path === '' || stripos($path, 'http://') === 0 || stripos($path, 'https://') === 0) {
            return $path;
        }

        $config = $this->getOssConfig();
        $host = trim((string)($config['host'] ?? ''));
        if ($host === '') {
            return $path;
        }
        if (stripos($host, 'http://') !== 0 && stripos($host, 'https://') !== 0) {
            $host = 'https://' . $host;
        }

        return rtrim($host, '/') . '/' . ltrim($path, '/');
    }

    private function logError(string $message): void
    {
        Log::write($message, 'error');
    }

    private function logWarning(string $message): void
    {
        Log::write($message, 'warning');
    }

    /**
     * 合并 JSON Body 与 form 参数
     */
    private function mergeRequestParams(): array
    {
        $params = $this->request->param();
        if (!empty($params['prompt']) || !empty($params['image']) || !empty($params['images'])) {
            return $params;
        }

        $content = $this->request->getInput();
        if (!is_string($content) || $content === '') {
            return $params;
        }

        $json = json_decode($content, true);
        if (!is_array($json)) {
            return $params;
        }

        return array_merge($params, $json);
    }
}