from flask import Blueprint, request, jsonify
from app.models import db, StudentGoal, Goal
from app.routes.auth import login_required_json

student_goals_bp = Blueprint("student_goals", __name__)

@student_goals_bp.route("/api/students/<int:student_id>/goals", methods=["GET"])
@login_required_json
def get_student_goals(student_id):
    records = StudentGoal.query.filter_by(student_id=student_id).all()
    return jsonify([r.to_dict() for r in records])

@student_goals_bp.route("/api/students/<int:student_id>/goals", methods=["POST"])
@login_required_json
def assign_goal(student_id):
    data = request.get_json()

    # 检查目标是否存在
    goal = Goal.query.get(data["goal_id"])
    if not goal:
        return jsonify({"error": "目标不存在"}), 404

    # 检查是否已分配
    existing = StudentGoal.query.filter_by(student_id=student_id, goal_id=data["goal_id"]).first()
    if existing:
        return jsonify({"error": "目标已分配"}), 400

    record = StudentGoal(
        student_id=student_id,
        goal_id=data["goal_id"],
        status=data.get("status", "未开始"),
        mastery_level=data.get("mastery_level", 1),
        deadline=data.get("deadline")
    )
    db.session.add(record)
    db.session.commit()
    return jsonify(record.to_dict()), 201

@student_goals_bp.route("/api/students/<int:student_id>/goals/<int:goal_id>", methods=["PUT"])
@login_required_json
def update_student_goal(student_id, goal_id):
    record = StudentGoal.query.filter_by(student_id=student_id, goal_id=goal_id).first_or_404()
    data = request.get_json()

    if "status" in data:
        record.status = data["status"]
        if data["status"] == "已完成" and not record.completed_at:
            from datetime import datetime
            record.completed_at = datetime.now()
    if "mastery_level" in data:
        record.mastery_level = data["mastery_level"]
    if "deadline" in data:
        record.deadline = data["deadline"]

    db.session.commit()
    return jsonify(record.to_dict())

@student_goals_bp.route("/api/students/<int:student_id>/goals/<int:goal_id>", methods=["DELETE"])
@login_required_json
def remove_student_goal(student_id, goal_id):
    record = StudentGoal.query.filter_by(student_id=student_id, goal_id=goal_id).first_or_404()
    db.session.delete(record)
    db.session.commit()
    return jsonify({"message": "移除成功"})