import { Router } from 'express';
import { accountService, transactionService } from '../data/db.service.js';
import type { Transaction, TransactionStatus, TransactionType } from '../types.js';

const router = Router();

// Helper function to transform update data
function transformUpdateData(updateData: Partial<Omit<Transaction, 'id'>>) {
  const typedUpdateData: {
    accountId?: string;
    date?: Date;
    description?: string;
    amount?: number;
    category?: string;
    status?: TransactionStatus;
    type?: TransactionType;
    notes?: string;
    tags?: string;
  } = {};

  // Convert string date to Date object if provided
  if (updateData.date) {
    typedUpdateData.date =
      typeof updateData.date === 'string' ? new Date(updateData.date) : updateData.date;
  }

  // Convert amount to number if provided
  if (updateData.amount !== undefined) {
    typedUpdateData.amount = Number(updateData.amount);
  }

  // Copy other fields
  if (updateData.accountId) typedUpdateData.accountId = updateData.accountId;
  if (updateData.description) typedUpdateData.description = updateData.description;
  if (updateData.category !== undefined)
    typedUpdateData.category = updateData.category || undefined;
  if (updateData.status) typedUpdateData.status = updateData.status as TransactionStatus;
  if (updateData.type) typedUpdateData.type = updateData.type as TransactionType;
  if (updateData.notes !== undefined) typedUpdateData.notes = updateData.notes || undefined;
  if (updateData.tags !== undefined) typedUpdateData.tags = updateData.tags || undefined;

  return typedUpdateData;
}

// POST /api/transactions - Create new transaction
// biome-ignore lint/suspicious/noExplicitAny: Express handler types require any for req/res
router.post('/', async (req: any, res: any) => {
  try {
    const transaction = req.body as Omit<Transaction, 'id'>;

    // Validate required fields
    if (
      !transaction.accountId ||
      !transaction.date ||
      !transaction.description ||
      transaction.amount === undefined
    ) {
      return res.status(400).json({ error: 'Missing required fields' });
    }

    // Validate account exists
    const account = await accountService.getById(transaction.accountId);
    if (!account) {
      return res.status(404).json({ error: 'Account not found' });
    }

    // Convert string date to Date object if needed
    const transactionDate =
      typeof transaction.date === 'string' ? new Date(transaction.date) : transaction.date;

    // Create new transaction with database service
    const newTransaction = await transactionService.create({
      accountId: transaction.accountId,
      date: transactionDate,
      description: transaction.description,
      amount: Number(transaction.amount),
      category: transaction.category || undefined,
      status: transaction.status as TransactionStatus,
      type: transaction.type as TransactionType,
      notes: transaction.notes || undefined,
      tags: transaction.tags || undefined,
    });

    // Convert Decimal to number for response
    const response = {
      ...newTransaction,
      amount: Number(newTransaction.amount),
    };

    res.status(201).json(response);
  } catch (error) {
    console.error('Error creating transaction:', error);
    res.status(500).json({ error: 'Failed to create transaction' });
  }
});

// GET /api/transactions/:id - Get single transaction
// biome-ignore lint/suspicious/noExplicitAny: Express handler types require any for req/res
router.get('/:id', async (req: any, res: any) => {
  try {
    const { id } = req.params;

    if (!id) {
      return res.status(400).json({ error: 'Transaction ID is required' });
    }

    const transaction = await transactionService.getById(id);

    if (!transaction) {
      return res.status(404).json({ error: 'Transaction not found' });
    }

    // Convert Decimal to number for response
    const response = {
      ...transaction,
      amount: Number(transaction.amount),
    };

    res.json(response);
  } catch (error) {
    console.error('Error fetching transaction:', error);
    res.status(500).json({ error: 'Failed to fetch transaction' });
  }
});

// PUT /api/transactions/:id - Update transaction
// biome-ignore lint/suspicious/noExplicitAny: Express handler types require any for req/res
router.put('/:id', async (req: any, res: any) => {
  try {
    const { id } = req.params;

    if (!id) {
      return res.status(400).json({ error: 'Transaction ID is required' });
    }

    // Check if transaction exists
    const existingTransaction = await transactionService.getById(id);
    if (!existingTransaction) {
      return res.status(404).json({ error: 'Transaction not found' });
    }

    const updateData = req.body as Partial<Omit<Transaction, 'id'>>;
    const typedUpdateData = transformUpdateData(updateData);

    const updatedTransaction = await transactionService.update(id, typedUpdateData);

    if (!updatedTransaction) {
      return res.status(404).json({ error: 'Transaction not found or could not be updated' });
    }

    // Convert Decimal to number for response
    const response = {
      ...updatedTransaction,
      amount: Number(updatedTransaction.amount),
    };

    res.json(response);
  } catch (error) {
    console.error('Error updating transaction:', error);
    res.status(500).json({ error: 'Failed to update transaction' });
  }
});

// DELETE /api/transactions/:id - Delete transaction
// biome-ignore lint/suspicious/noExplicitAny: Express handler types require any for req/res
router.delete('/:id', async (req: any, res: any) => {
  try {
    const { id } = req.params;

    if (!id) {
      return res.status(400).json({ error: 'Transaction ID is required' });
    }

    // Check if transaction exists
    const existingTransaction = await transactionService.getById(id);
    if (!existingTransaction) {
      return res.status(404).json({ error: 'Transaction not found' });
    }

    await transactionService.delete(id);

    res.status(204).send();
  } catch (error) {
    console.error('Error deleting transaction:', error);
    res.status(500).json({ error: 'Failed to delete transaction' });
  }
});

export default router;