const { StudentDetail, UserProfile, UsersAuth, Class } = require('../models');
const { cacheUtils } = require('../config/redis');

/**
 * Student Controller - Quản lý học sinh
 */
class StudentController {
  /**
   * Get all students with pagination and caching
   */
  async getAllStudents(req, res, next) {
    try {
      const { page = 1, limit = 20, status, class_id } = req.query;
      const offset = (page - 1) * limit;
      
      const cacheKey = `students:list:${page}:${limit}:${status || 'all'}:${class_id || 'all'}`;
      
      const cached = await cacheUtils.get(cacheKey);
      if (cached) {
        return res.json({
          success: true,
          data: cached,
          cached: true,
        });
      }
      
      const where = {};
      if (status) where.status = status;
      if (class_id) where.current_class_id = class_id;
      
      const { count, rows } = await StudentDetail.findAndCountAll({
        where,
        limit: parseInt(limit),
        offset: parseInt(offset),
        include: [
          {
            model: UserProfile,
            as: 'profile',
            attributes: ['full_name', 'phone', 'date_of_birth', 'gender'],
          },
          {
            model: Class,
            as: 'currentClass',
            attributes: ['class_code', 'class_name', 'grade_level'],
          },
        ],
        order: [['created_at', 'DESC']],
      });
      
      const result = {
        students: rows,
        pagination: {
          total: count,
          page: parseInt(page),
          limit: parseInt(limit),
          totalPages: Math.ceil(count / limit),
        },
      };
      
      await cacheUtils.set(cacheKey, result, 1800);
      
      res.json({
        success: true,
        data: result,
        cached: false,
      });
    } catch (error) {
      next(error);
    }
  }

  /**
   * Get student by ID
   */
  async getStudentById(req, res, next) {
    try {
      const { id } = req.params;
      const cacheKey = `student:${id}`;
      
      const cached = await cacheUtils.get(cacheKey);
      if (cached) {
        return res.json({
          success: true,
          data: cached,
          cached: true,
        });
      }
      
      const student = await StudentDetail.findByPk(id, {
        include: [
          {
            model: UserProfile,
            as: 'profile',
          },
          {
            model: Class,
            as: 'currentClass',
          },
        ],
      });
      
      if (!student) {
        return res.status(404).json({
          success: false,
          message: 'Student not found',
        });
      }
      
      await cacheUtils.set(cacheKey, student, 3600);
      
      res.json({
        success: true,
        data: student,
        cached: false,
      });
    } catch (error) {
      next(error);
    }
  }

  /**
   * Create new student
   */
  async createStudent(req, res, next) {
    try {
      const studentData = req.body;
      
      const newStudent = await StudentDetail.create(studentData);
      
      await cacheUtils.deletePattern('students:list:*');
      
      res.status(201).json({
        success: true,
        message: 'Student created successfully',
        data: newStudent,
      });
    } catch (error) {
      next(error);
    }
  }

  /**
   * Update student
   */
  async updateStudent(req, res, next) {
    try {
      const { id } = req.params;
      const updates = req.body;
      
      const student = await StudentDetail.findByPk(id);
      if (!student) {
        return res.status(404).json({
          success: false,
          message: 'Student not found',
        });
      }
      
      await student.update(updates);
      
      await cacheUtils.delete(`student:${id}`);
      await cacheUtils.deletePattern('students:list:*');
      
      res.status(200).json({
        success: true,
        message: 'Student updated successfully',
        data: student,
      });
    } catch (error) {
      next(error);
    }
  }

  /**
   * Delete student (update status to dropped)
   */
  async deleteStudent(req, res, next) {
    try {
      const { id } = req.params;
      
      const student = await StudentDetail.findByPk(id);
      if (!student) {
        return res.status(404).json({
          success: false,
          message: 'Student not found',
        });
      }
      
      await student.update({ status: 'dropped' });
      
      await cacheUtils.delete(`student:${id}`);
      await cacheUtils.deletePattern('students:list:*');
      
      res.status(200).json({
        success: true,
        message: 'Student status updated to dropped',
        data: student,
      });
    } catch (error) {
      next(error);
    }
  }

  /**
   * Get student datatypes
   */
  async getStudentDatatypes(req, res, next) {
    try {
      const datatypes = StudentDetail.rawAttributes;
      res.json({
        success: true,
        data: datatypes,
      });
    } catch (error) {
      next(error);
    }
  }
}

module.exports = new StudentController();