"""压缩机 3D 部件查看服务（FastAPI）。

接口：
    GET  /api/models          可用模型列表
    GET  /api/state?model=x   读取配色状态
    POST /api/state?model=x   保存配色状态
    GET  /models/<file>       GLB / glTF 模型文件
    GET  /*                   前端构建产物（frontend/dist），SPA 回退 index.html
"""

from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse

from config import FRONTEND_DIST
from routers import alarms, fault_map, files, scenes, series, state

app = FastAPI(title="压缩机 3D 部件查看服务", version="0.1.0")
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)

app.include_router(alarms.router)
app.include_router(fault_map.router)
app.include_router(files.router)
app.include_router(scenes.router)
app.include_router(series.router)
app.include_router(state.router)


@app.get("/{full_path:path}")
def serve_frontend(full_path: str) -> FileResponse:
    if full_path.startswith(("api/", "models/")):
        raise HTTPException(status_code=404, detail="Not Found")
    resolved_dist = FRONTEND_DIST.resolve()
    if full_path:
        candidate = (FRONTEND_DIST / full_path).resolve()
        if resolved_dist in candidate.parents and candidate.is_file():
            return FileResponse(candidate)
    index = FRONTEND_DIST / "index.html"
    if index.is_file():
        return FileResponse(index)
    raise HTTPException(status_code=404, detail="前端未构建：请先 cd 3d/frontend && npm run build")