import { type NextRequest, NextResponse } from "next/server"
import { generateText } from "ai"

export async function POST(request: NextRequest) {
  try {
    const formData = await request.formData()
    const file = formData.get("file") as File
    const targetLanguage = formData.get("targetLanguage") as string

    if (!file || !targetLanguage) {
      return NextResponse.json({ error: "缺少必要參數" }, { status: 400 })
    }

    // Extract text from PDF
    const arrayBuffer = await file.arrayBuffer()
    const buffer = Buffer.from(arrayBuffer)

    // For demo purposes, we'll simulate PDF text extraction
    // In production, you'd use a library like pdf-parse
    const pdfText = `這是從PDF提取的示例文本。在實際應用中，這裡會是真實的PDF內容。

這個應用展示了如何使用AI來翻譯文檔內容。您可以上傳任何PDF文件，選擇目標語言，然後獲得翻譯結果。

主要功能包括：
- 支持多種語言翻譯
- 清爽的用戶介面
- 簡單易用的操作流程`

    // Get language name for better translation context
    const languageNames: Record<string, string> = {
      "zh-TW": "繁體中文",
      "zh-CN": "簡體中文",
      en: "English",
      ja: "日本語",
      ko: "한국어",
      es: "Español",
      fr: "Français",
      de: "Deutsch",
      it: "Italiano",
      pt: "Português",
      ru: "Русский",
      ar: "العربية",
      th: "ไทย",
      vi: "Tiếng Việt",
    }

    const targetLanguageName = languageNames[targetLanguage] || targetLanguage

    // Translate using AI SDK
    const { text: translatedText } = await generateText({
      model: "openai/gpt-4o-mini",
      prompt: `請將以下文本翻譯成${targetLanguageName}。保持原文的格式和結構，只翻譯內容：

${pdfText}`,
    })

    return NextResponse.json({ translatedText })
  } catch (error) {
    console.error("翻譯錯誤:", error)
    return NextResponse.json({ error: "翻譯過程中發生錯誤" }, { status: 500 })
  }
}