from pathlib import Path

from fastapi import APIRouter, Depends, File, HTTPException, UploadFile
from sqlalchemy.orm import Session

from backend.auth import get_current_user
from backend.database import get_db
from backend.models import ImportHistory, Question
from backend.schemas import ImportHistoryOut, QuestionOut
from backend.services.excel_service import create_template_bytes, parse_excel_file
from backend.services.file_utils import save_upload
from backend.services.parser import DMXAPIService, extract_metadata

router = APIRouter(dependencies=[Depends(get_current_user)])


@router.post("/ai/parse")
def parse_by_ai(file: UploadFile = File(...)) -> dict:
    path = save_upload(file)
    parser = DMXAPIService()
    metadata = extract_metadata(file.filename or path.name)
    questions = parser.parse_file(str(path))
    preview = []
    for q in questions:
        preview.append(
            {
                "chapter": metadata["chapter"],
                "primary_knowledge": "",
                "secondary_knowledge": metadata["secondary_knowledge"],
                "question_type": metadata["question_type"],
                "difficulty": metadata["difficulty"],
                "stem": q.get("题干", ""),
                "option_a": q.get("选项A", ""),
                "option_b": q.get("选项B", ""),
                "option_c": q.get("选项C", ""),
                "option_d": q.get("选项D", ""),
                "answer": q.get("正确答案", ""),
                "explanation": q.get("解析", ""),
                "notes": q.get("备注", ""),
                "source_file": metadata["source_file"],
            }
        )
    return {"filename": file.filename, "preview": preview}


@router.post("/ai/confirm", response_model=list[QuestionOut])
def confirm_ai_import(payload: list[dict], db: Session = Depends(get_db)) -> list[QuestionOut]:
    if not payload:
        raise HTTPException(status_code=400, detail="没有可导入数据")
    items = [Question(**item) for item in payload]
    db.add_all(items)
    db.add(
        ImportHistory(
            filename=items[0].source_file if items else "",
            method="ai",
            question_count=len(items),
            status="success",
        )
    )
    db.commit()
    for item in items:
        db.refresh(item)
    return [QuestionOut.model_validate(item) for item in items]


@router.post("/excel", response_model=list[QuestionOut])
def import_excel(file: UploadFile = File(...), db: Session = Depends(get_db)) -> list[QuestionOut]:
    path = save_upload(file)
    if Path(path).suffix.lower() not in [".xlsx", ".xlsm", ".xltx", ".xltm"]:
        raise HTTPException(status_code=400, detail="仅支持 Excel 文件")
    rows = parse_excel_file(Path(path))
    items = [Question(**row) for row in rows]
    db.add_all(items)
    db.add(
        ImportHistory(
            filename=file.filename or "",
            method="excel",
            question_count=len(items),
            status="success",
        )
    )
    db.commit()
    for item in items:
        db.refresh(item)
    return [QuestionOut.model_validate(item) for item in items]


@router.get("/template")
def download_template() -> dict:
    content = create_template_bytes()
    return {"filename": "question_template.xlsx", "content_base64": content.hex()}


@router.get("/history", response_model=list[ImportHistoryOut])
def import_history(db: Session = Depends(get_db)) -> list[ImportHistoryOut]:
    rows = db.query(ImportHistory).order_by(ImportHistory.created_at.desc()).limit(100).all()
    return [ImportHistoryOut.model_validate(r) for r in rows]