বই লোন দেয়ার ফিচার যোগ করি

// Define the schema for book loans
const loanSchema = new mongoose.Schema({
    book: { type: mongoose.Schema.Types.ObjectId, ref: 'Book', required: true },
    member: { type: mongoose.Schema.Types.ObjectId, ref: 'Member', required: true },
    issueDate: { type: Date, default: Date.now },
    dueDate: { type: Date, required: true },
    returnDate: { type: Date },
  });
  
const Loan = mongoose.model('Loan', loanSchema );  

module.exports = { Author, Book ,Member,Loan};

const { Author, Book,Member,Loan } = require('./models');

// Create a new loan
router.post('/loans', async (req, res) => {
    try {
      const { book, member, dueDate } = req.body;
      const newLoan = new Loan({ book, member, dueDate });
      const savedLoan = await newLoan.save();
      res.json(savedLoan);
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: 'Failed to create loan' });
    }
  });
  
  // Get all loans
  router.get('/loans', async (req, res) => {
    try {
      const loans = await Loan.find();
      res.json(loans);
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: 'Failed to retrieve loans' });
    }
  });
  
  // Get a loan by ID
  router.get('/loans/:id', async (req, res) => {
    try {
      const loanId = req.params.id;
      const loan = await Loan.findById(loanId);
  
      if (!loan) {
        return res.status(404).json({ error: 'Loan not found' });
      }
  
      res.json(loan);
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: 'Failed to find loan' });
    }
  });
  
  // Update a loan by ID
  router.put('/loans/:id', async (req, res) => {
    try {
      const loanId = req.params.id;
      const { book, member, dueDate, returnDate } = req.body;
  
      const updatedLoan = await Loan.findByIdAndUpdate(
        loanId,
        { book, member, dueDate, returnDate },
        { new: true }
      );
  
      if (!updatedLoan) {
        return res.status(404).json({ error: 'Loan not found' });
      }
  
      res.json(updatedLoan);
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: 'Failed to update loan' });
    }
  });
  
  // Delete a loan by ID
  router.delete('/loans/:id', async (req, res) => {
    try {
      const loanId = req.params.id;
  
      const deletedLoan = await Loan.findByIdAndDelete(loanId);
  
      if (!deletedLoan) {
        return res.status(404).json({ error: 'Loan not found' });
      }
  
      res.json({ message: 'Loan deleted successfully' });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: 'Failed to delete loan' });
    }
  });