import os
import requests
import json
from flask import Flask, request, jsonify, send_from_directory

app = Flask(__name__, static_folder='static', static_url_path='')

GEMINI_API_KEY = os.environ.get("GEMINI_API_KEY")
GEMINI_API_URL = "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro:generateContent"

SYSTEM_PROMPT = """
你是一个世界顶级的皮肤科医生AI助手。你的任务是基于用户上传的皮肤图像和病历文本，进行专业的临床诊疗辅助分析。
你的输出必须是一个单一、有效的JSON对象，不包含任何JSON格式之外的文字或标记（例如不要使用 "```json"）。
请严格遵循以下JSON结构：
{
  "image_features": ["从图像中识别出的关键皮损形态学特征列表", "例如：色素网络不规则", "例如：蓝白结构"],
  "differential_diagnosis": [
    { "diagnosis": "可能性最高的诊断名称", "likelihood": "高", "evidence": "支持该诊断的关键图像和文本依据" },
    { "diagnosis": "可能性次之的诊断名称", "likelihood": "中", "evidence": "支持该诊断的关键依据" }
  ],
  "comprehensive_analysis": "一段对整个病情的全面、综合性分析和总结。",
  "recommendations": {
    "further_examinations": ["建议的下一步检查列表", "例如：皮肤镜检查", "例如：皮肤活检"],
    "treatment_suggestions": ["初步的、符合临床指南的治疗方向建议列表", "例如：外用糖皮质激素", "例如：建议手术切除"]
  }
}
"""

@app.route('/healthz')
def health_check():
    """专门用于平台健康检查的路由，确保100%稳定"""
    return "OK", 200

@app.route('/')
def index():
    """提供前端HTML页面"""
    return send_from_directory(app.static_folder, 'index.html')

@app.route('/api/analyze', methods=['POST'])
def analyze_skin():
    """处理分析请求的核心API端点"""
    if not GEMINI_API_KEY:
        return jsonify({"error": "服务端未配置GEMINI_API_KEY"}), 500

    data = request.json
    if not data or 'image' not in data or 'text' not in data:
        return jsonify({"error": "请求中缺少图像或文本信息"}), 400

    image_base64 = data.get('image')
    text_prompt = data.get('text')

    headers = {'Content-Type': 'application/json'}
    
    payload = {
        "contents": [{"parts": [
            {"text": SYSTEM_PROMPT},
            {"text": f"临床病历信息如下：\n{text_prompt}"},
            {"inline_data": {"mime_type": "image/jpeg", "data": image_base64}}
        ]}]
    }

    try:
        response = requests.post(f"{GEMINI_API_URL}?key={GEMINI_API_KEY}", headers=headers, json=payload, timeout=60)
        response.raise_for_status()
        
        gemini_result = response.json()
        
        # 稳健地提取内容
        analysis_content_string = gemini_result['candidates']['content']['parts']['text']
        parsed_json = json.loads(analysis_content_string)
        
        return jsonify(parsed_json)

    except requests.exceptions.RequestException as e:
        return jsonify({"error": f"调用Gemini API时发生网络错误: {e}"}), 500
    except (KeyError, IndexError, TypeError):
        error_details = response.json() if 'response' in locals() else "No response from API"
        return jsonify({"error": "解析Gemini API响应失败，格式不正确", "details": error_details}), 500
    except json.JSONDecodeError:
        return jsonify({"error": "Gemini API未返回有效的JSON格式", "details": analysis_content_string}), 500
    except Exception as e:
        return jsonify({"error": f"发生未知错误: {e}"}), 500

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8080)