import { eq, and } from "drizzle-orm";
import { getDb } from "../config/database.js";
import {
  lessonPlans,
  type LessonPlan,
  type NewLessonPlan,
} from "./lesson-plans.schema.js";

export class LessonPlansRepository {
  async findById(id: string): Promise<LessonPlan | undefined> {
    const [result] = await getDb()
      .select()
      .from(lessonPlans)
      .where(eq(lessonPlans.id, id))
      .limit(1);
    return result;
  }

  async findByTeacher(query: {
    teacherId: string;
    classId?: string;
    subjectId?: string;
  }): Promise<LessonPlan[]> {
    const db = getDb();
    const conditions = [eq(lessonPlans.teacherId, query.teacherId)];
    if (query.classId) {
      conditions.push(eq(lessonPlans.classId, query.classId));
    }
    if (query.subjectId) {
      conditions.push(eq(lessonPlans.subjectId, query.subjectId));
    }
    return db
      .select()
      .from(lessonPlans)
      .where(and(...conditions));
  }

  async findByStudent(query: {
    studentId: string;
    classId?: string;
  }): Promise<LessonPlan[]> {
    // 学生视角：按班级查询教师发布的备课计划
    // studentId 不直接关联备课计划（备课计划是教师创建的），
    // 通过 classId 过滤学生所在班级的备课计划
    const db = getDb();
    const conditions = [eq(lessonPlans.status, "published")];
    if (query.classId) {
      conditions.push(eq(lessonPlans.classId, query.classId));
    }
    return db
      .select()
      .from(lessonPlans)
      .where(and(...conditions));
  }

  async create(data: NewLessonPlan): Promise<void> {
    await getDb().insert(lessonPlans).values(data);
  }

  async update(id: string, data: Partial<NewLessonPlan>): Promise<void> {
    await getDb().update(lessonPlans).set(data).where(eq(lessonPlans.id, id));
  }

  async delete(id: string): Promise<void> {
    await getDb().delete(lessonPlans).where(eq(lessonPlans.id, id));
  }
}

export const lessonPlansRepository = new LessonPlansRepository();