"""学习总览。"""
from __future__ import annotations

from fastapi import APIRouter, Depends
from sqlalchemy.orm import Session

from database import get_db
from dependencies import require_learning_user
from models import AttemptSession, User
from schemas import KnowledgeOut, MetricItem, OverviewOut, PlanOut
from services.mastery_engine import snapshot, status_for
from services.recommendation import build_plan


router = APIRouter(tags=["overview"])


@router.get("/overview", response_model=OverviewOut)
def get_overview(
    db: Session = Depends(get_db),
    user: User = Depends(require_learning_user),
):
    total_questions = (
        db.query(AttemptSession.total)
        .filter(AttemptSession.user_id == user.id)
        .all()
    )
    total_answers = sum(row.total for row in total_questions)
    total_correct = (
        db.query(AttemptSession.correct)
        .filter(AttemptSession.user_id == user.id)
        .all()
    )
    correct_answers = sum(row.correct for row in total_correct)
    accuracy = correct_answers / total_answers * 100 if total_answers else 0.0

    knowledge = snapshot(db, user.id)
    weak_count = sum(1 for k in knowledge if k.mastery < 60)

    metrics = [
        MetricItem(label="累计题目", value=str(total_answers)),
        MetricItem(
            label="累计正确率",
            value=f"{accuracy:.1f}%" if total_answers else "0%",
        ),
        MetricItem(label="薄弱知识点", value=str(weak_count)),
        MetricItem(label="当前阶段", value="L2 基础应用"),
    ]
    plan = build_plan(db, user.id)
    return OverviewOut(
        metrics=metrics,
        knowledge=[
            KnowledgeOut(
                id=k.id,
                knowledge_id=k.knowledge_id,
                name=k.name,
                mastery=k.mastery,
                position=k.position,
                status=status_for(k.mastery),
                domain=k.domain,
                category=k.category,
            )
            for k in knowledge
        ],
        plan=PlanOut(
            notice=plan["notice"],
            focus_names=plan["focus_names"],
            steps=plan["steps"],
        ),
    )