import { Handlers } from 'fresh/server.ts';

import { Budget, Expense, FreshContextState } from '/lib/types.ts';
import { getBudgets, getExpenseById, getExpenses, updateExpense } from '/lib/data/expenses.ts';

interface Data {}

export interface RequestBody {
  id: string;
  cost: number;
  description: string;
  budget: string;
  date: string;
  is_recurring: boolean;
  month: string;
}

export interface ResponseBody {
  success: boolean;
  newExpenses: Expense[];
  newBudgets: Budget[];
}

export const handler: Handlers<Data, FreshContextState> = {
  async POST(request, context) {
    if (!context.state.user) {
      return new Response('Unauthorized', { status: 401 });
    }

    const requestBody = await request.clone().json() as RequestBody;

    if (
      !requestBody.id || !requestBody.cost || Number.isNaN(requestBody.cost) || !requestBody.description ||
      !requestBody.month || !requestBody.month.match(/^\d{4}-\d{2}$/)
    ) {
      return new Response('Bad request', { status: 400 });
    }

    const expense = await getExpenseById(context.state.user.id, requestBody.id);

    if (!expense) {
      return new Response('Not found', { status: 404 });
    }

    if (!requestBody.budget) {
      requestBody.budget = 'Misc';
    }

    if (!requestBody.date) {
      requestBody.date = new Date().toISOString().substring(0, 10);
    }

    if (!requestBody.date.match(/^\d{4}-\d{2}-\d{2}$/)) {
      return new Response('Bad request', { status: 400 });
    }

    if (!requestBody.is_recurring) {
      requestBody.is_recurring = false;
    }

    expense.cost = requestBody.cost;
    expense.description = requestBody.description;
    expense.budget = requestBody.budget;
    expense.date = requestBody.date;
    expense.is_recurring = requestBody.is_recurring;

    try {
      await updateExpense(expense);
    } catch (error) {
      console.error(error);
      return new Response(`${error}`, { status: 500 });
    }

    const newExpenses = await getExpenses(context.state.user.id, requestBody.month);

    const newBudgets = await getBudgets(context.state.user.id, requestBody.month);

    const responseBody: ResponseBody = { success: true, newExpenses, newBudgets };

    return new Response(JSON.stringify(responseBody));
  },
};