fix:bug

backend/app/services/ai_service.py

@@ -0,0 +1,108 @@
+import json
+import os
+from typing import Any, Dict
+
+from openai import AsyncOpenAI
+
+
+_client: AsyncOpenAI | None = None
+
+
+def get_ai_client() -> AsyncOpenAI:
+    """
+    Create (or reuse) a singleton AsyncOpenAI client.
+
+    The client is configured via:
+    - AI_API_KEY / OPENAI_API_KEY
+    - AI_BASE_URL (optional, defaults to official OpenAI endpoint)
+    - AI_MODEL (optional, defaults to gpt-4.1-mini or a similar capable model)
+    """
+    global _client
+    if _client is not None:
+        return _client
+
+    api_key = os.getenv("AI_API_KEY") or os.getenv("OPENAI_API_KEY")
+    if not api_key:
+        raise RuntimeError("AI_API_KEY or OPENAI_API_KEY must be set in environment.")
+
+    base_url = os.getenv("AI_BASE_URL")  # can point to OpenAI, DeepSeek, Qwen, etc.
+
+    _client = AsyncOpenAI(
+        api_key=api_key,
+        base_url=base_url or None,
+    )
+    return _client
+
+
+def _build_requirement_prompt(raw_text: str) -> str:
+    """
+    Build a clear system/user prompt for requirement analysis.
+    The model must output valid JSON only.
+    """
+    return (
+        "你是一名资深的系统架构师，请阅读以下来自客户的原始需求文本，"
+        "提炼出清晰的交付方案，并严格按照指定 JSON 结构输出。\n\n"
+        "【要求】\n"
+        "1. 按功能模块拆分需求。\n"
+        "2. 每个模块给出简要说明和技术实现思路。\n"
+        "3. 估算建议工时（以人天或人小时为单位，使用数字）。\n"
+        "4. 可以根据你的经验给出每个模块的单价与小计金额，并给出总金额，"
+        "方便后续生成报价单。\n\n"
+        "【返回格式】请只返回 JSON，不要包含任何额外说明文字：\n"
+        "{\n"
+        '  "modules": [\n'
+        "    {\n"
+        '      "name": "模块名称",\n'
+        '      "description": "模块说明（可以为 Markdown 格式）",\n'
+        '      "technical_approach": "技术实现思路（Markdown 格式）",\n'
+        '      "estimated_hours": 16,\n'
+        '      "unit_price": 800,\n'
+        '      "subtotal": 12800\n'
+        "    }\n"
+        "  ],\n"
+        '  "total_estimated_hours": 40,\n'
+        '  "total_amount": 32000,\n'
+        '  "notes": "整体方案备注（可选，Markdown 格式）"\n'
+        "}\n\n"
+        f"【客户原始需求】\n{raw_text}"
+    )
+
+
+async def analyze_requirement(raw_text: str) -> Dict[str, Any]:
+    """
+    Call the AI model to analyze customer requirements.
+
+    Returns a Python dict matching the JSON structure described
+    in `_build_requirement_prompt`.
+    """
+    client = get_ai_client()
+    model = os.getenv("AI_MODEL", "gpt-4.1-mini")
+
+    prompt = _build_requirement_prompt(raw_text)
+
+    completion = await client.chat.completions.create(
+        model=model,
+        response_format={"type": "json_object"},
+        messages=[
+            {
+                "role": "system",
+                "content": (
+                    "你是一名严谨的系统架构师，只能输出有效的 JSON，不要输出任何解释文字。"
+                ),
+            },
+            {
+                "role": "user",
+                "content": prompt,
+            },
+        ],
+        temperature=0.2,
+    )
+
+    content = completion.choices[0].message.content or "{}"
+    try:
+        data: Dict[str, Any] = json.loads(content)
+    except json.JSONDecodeError as exc:
+        raise RuntimeError(f"AI 返回的内容不是合法 JSON：{content}") from exc
+
+    return data
+