geminiService.ts

import { GoogleGenAI, Type, Modality } from "@google/genai";

const getAI = () => new GoogleGenAI({ apiKey: process.env.API_KEY || '' });

export const analyzeMedicationImage = async (base64Image: string) => {
  const ai = getAI();
  const prompt = `分析这张药品图片。请使用中文提取以下详细信息并以 JSON 格式输出：
    - name: 字符串 (药品名称)
    - type: "处方药" | "保健品" | "非处方药" | "注射剂"
    - dosage: 字符串 (例如 500mg)
    - instructions: 字符串 (用法用量说明)
    - withFood: 布尔值 (是否随餐服用)
    - sideEffects: 字符串数组 (潜在副作用列表)
    - priority: "普通" | "重要" | "紧急"
    - reminderTimes: 字符串数组 (根据 frequency 建议合理的服药时间点，如 ["08:00"])
    请确保严格遵循 JSON 结构。`;

  try {
    const response = await ai.models.generateContent({
      model: "gemini-3-pro-preview",
      contents: {
        parts: [
          { inlineData: { data: base64Image, mimeType: "image/jpeg" } },
          { text: prompt }
        ]
      },
      config: {
        responseMimeType: "application/json",
        responseSchema: {
          type: Type.OBJECT,
          properties: {
            name: { type: Type.STRING },
            type: { type: Type.STRING },
            dosage: { type: Type.STRING },
            instructions: { type: Type.STRING },
            withFood: { type: Type.BOOLEAN },
            sideEffects: { type: Type.ARRAY, items: { type: Type.STRING } },
            priority: { type: Type.STRING },
            reminderTimes: { type: Type.ARRAY, items: { type: Type.STRING } }
          }
        }
      }
    });

    return JSON.parse(response.text || '{}');
  } catch (error) {
    console.error("Gemini 分析错误:", error);
    return null;
  }
};

export const askAboutMedication = async (medName: string, question: string) => {
  const ai = getAI();
  const prompt = `关于药物 "${medName}"，用户想知道：${question}。
  请作为专业的健康助手提供简明的中文解答，必须包含免责声明：本回复仅供 AI 参考，具体请遵医嘱。
  字数控制在 150 字以内。`;

  try {
    const response = await ai.models.generateContent({
      model: "gemini-3-flash-preview",
      contents: prompt,
    });
    return response.text;
  } catch (error) {
    console.error("AI 问答错误:", error);
    return "抱歉，由于网络原因暂时无法回答该问题。";
  }
};

export const checkDrugInteractions = async (newMed: string, existingMeds: string[]) => {
  const ai = getAI();
  const prompt = `我准备服用新药 "${newMed}"。我目前正在服用的药物有：${existingMeds.join(', ')}。
  请分析这些药物之间是否存在明显的药性相冲或相互作用。
  如果存在风险，请提供简短的中文警告信息；如果没有明显冲突，请回复“暂未发现明显药物冲突”。
  字数请控制在 100 字以内。`;

  try {
    const response = await ai.models.generateContent({
      model: "gemini-3-flash-preview",
      contents: prompt,
    });
    return response.text || "无法获取药性相冲信息。";
  } catch (error) {
    console.error("冲突检查错误:", error);
    return "由于网络原因，无法检查药性相冲情况。";
  }
};

export const playMedReminder = async (medName: string) => {
  const ai = getAI();
  const text = `该吃药啦，这是您的 ${medName}。请记得核对用量。`;
  
  try {
    const response = await ai.models.generateContent({
      model: "gemini-2.5-flash-preview-tts",
      contents: [{ parts: [{ text }] }],
      config: {
        responseModalities: [Modality.AUDIO],
        speechConfig: {
          voiceConfig: {
            prebuiltVoiceConfig: { voiceName: 'Kore' },
          },
        },
      },
    });

    const base64Audio = response.candidates?.[0]?.content?.parts?.[0]?.inlineData?.data;
    if (base64Audio) {
      const audioCtx = new (window.AudioContext || (window as any).webkitAudioContext)({ sampleRate: 24000 });
      const decoded = decode(base64Audio);
      const buffer = await decodeAudioData(decoded, audioCtx, 24000, 1);
      const source = audioCtx.createBufferSource();
      source.buffer = buffer;
      source.connect(audioCtx.destination);
      source.start();
    }
  } catch (error) {
    console.error("Gemini TTS 错误:", error);
    const msg = new SpeechSynthesisUtterance(text);
    msg.lang = 'zh-CN';
    window.speechSynthesis.speak(msg);
  }
};

function decode(base64: string) {
  const binaryString = atob(base64);
  const bytes = new Uint8Array(binaryString.length);
  for (let i = 0; i < binaryString.length; i++) {
    bytes[i] = binaryString.charCodeAt(i);
  }
  return bytes;
}

async function decodeAudioData(data: Uint8Array, ctx: AudioContext, sampleRate: number, numChannels: number): Promise<AudioBuffer> {
  const dataInt16 = new Int16Array(data.buffer);
  const frameCount = dataInt16.length / numChannels;
  const buffer = ctx.createBuffer(numChannels, frameCount, sampleRate);
  for (let channel = 0; channel < numChannels; channel++) {
    const channelData = buffer.getChannelData(channel);
    for (let i = 0; i < frameCount; i++) {
      channelData[i] = dataInt16[i * numChannels + channel] / 32768.0;
    }
  }
  return buffer;
}