# api/statistics.py
# 统计分析模块接口：动态年龄查询、班级统计、成绩统计、就业统计、高级筛选器、聚合统计
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session

from core.deps import require_roles
from dao.statistics_dao import StatisticsDAO, FilterBuilder
from database import get_db
from scheme.statistics import (
    FilterRequest,
    FilterResponse,
    ClassGenderStat,
    AllAboveStudent,
    FailStudent,
    ClassExamAvg,
    TopSalaryStudent,
    EmploymentDuration,
    ClassAvgDuration,
    ScoreVolatility,
    EmploymentFunnel,
)
from scheme.students import StudentResponse

router = APIRouter()

# 统计模块统一要求 admin / teacher 角色（各接口通过 Depends(require_roles(...)) 校验）


# ==================== 2.6.1 基本信息动态统计 ====================
@router.get("/students/by-age", response_model=list[StudentResponse], summary="动态年龄范围查询")
async def students_by_age(
    op: str = Query(..., description="比较条件：gt/lt/eq/gte/lte/between"),
    value: int = Query(None, description="op 为 gt/lt/eq/gte/lte 时必填"),
    min_value: int = Query(None, description="op=between 时的下界"),
    max_value: int = Query(None, description="op=between 时的上界"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    try:
        items = StatisticsDAO.students_by_age(db, op=op, value=value, min_value=min_value, max_value=max_value)
    except ValueError as e:
        raise HTTPException(status_code=400, detail=str(e))
    return items


@router.get("/class/gender-stats", response_model=list[ClassGenderStat], summary="多维度班级统计（总人数+男女分布）")
async def class_gender_stats(
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.class_gender_stats(db)


# ==================== 2.6.2 成绩综合统计 ====================
@router.get("/score/all-above", response_model=list[AllAboveStudent], summary="每次考试都在分数线以上的学生")
async def score_all_above(
    line: float = Query(..., ge=0, le=100, description="分数线，如 80"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.students_all_above(db, line)


@router.get("/score/fail", response_model=list[FailStudent], summary="不及格次数>=N的学生（含明细）")
async def score_fail(
    times: int = Query(..., ge=1, description="不及格次数阈值，如 2"),
    line: float = Query(60.0, ge=0, le=100, description="及格线，默认 60"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.fail_students(db, times, line)


@router.get("/score/class-avg", response_model=list[ClassExamAvg], summary="每次考试每个班级平均分（支持动态排序）")
async def score_class_avg(
    exam_id: int = Query(None, ge=1, description="考核序次（不传则返回所有考核）"),
    order: str = Query("desc", pattern="^(asc|desc)$", description="按平均分排序方向"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.class_exam_avg(db, exam_id=exam_id, order=order)


# ==================== 2.6.3 就业数据统计 ====================
@router.get("/employment/top-salary", response_model=list[TopSalaryStudent], summary="就业薪资排名 Top N")
async def employment_top_salary(
    n: int = Query(..., ge=1, le=100, description="取前 N 名"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.top_salary(db, n)


@router.get("/employment/duration", response_model=list[EmploymentDuration], summary="每个学生的就业时长（天）")
async def employment_duration(
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.employment_durations(db)


@router.get("/employment/class-avg-duration", response_model=list[ClassAvgDuration], summary="每个班级平均就业时长")
async def employment_class_avg_duration(
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.class_avg_duration(db)


# ==================== 2.7.1 通用高级筛选器 ====================
@router.post("/filter", response_model=FilterResponse, summary="通用高级筛选器（AND/OR 嵌套规则）")
async def advanced_filter(
    body: FilterRequest,
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    try:
        total, items = FilterBuilder.query_students(db, body.rules)
    except ValueError as e:
        raise HTTPException(status_code=400, detail=str(e))
    # 组装为字典响应（含班级名称）
    data = []
    for s in items:
        row = StudentResponse.model_validate(s).model_dump()
        if s.classes:
            row["class_name"] = s.classes.class_name
        data.append(row)
    return FilterResponse(total=total, items=data)


# ==================== 2.7.2 多维度聚合统计 ====================
@router.get("/score/volatility", response_model=list[ScoreVolatility], summary="成绩波动最大 Top N（最大分差）")
async def score_volatility(
    top_n: int = Query(5, ge=1, le=50, description="取前 N 名，默认 5"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.score_volatility(db, top_n)


@router.get("/employment/funnel", response_model=list[EmploymentFunnel], summary="班级就业漏斗（总人数→已就业→高薪→就业率）")
async def employment_funnel(
    high_salary_line: float = Query(10000.0, ge=0, description="高薪线，默认 10000"),
    db: Session = Depends(get_db),
    _user=Depends(require_roles("admin", "teacher")),
):
    return StatisticsDAO.employment_funnel(db, high_salary_line)