'use server'

import { z } from 'zod';
import postgres from 'postgres';
import { revalidatePath } from 'next/cache';
import { redirect } from 'next/navigation';
import { signIn } from '@/auth';
import { AuthError } from 'next-auth';

const sql = postgres(process.env.DATABASE_URL!, {ssl:'require'});

const formSchema = z.object({
    id: z.string(),
    customerId: z.string({
        invalid_type_error: 'Please select a customer.'
    }),
    amount: z.coerce.number().gt(0, {message: 'Please enter an amount greater than $0.'}),
    status: z.enum(['pending', 'paid'], {
        invalid_type_error: 'Please select an invoice status.'
    }),
    date: z.string(),
})

const CreateInvoice = formSchema.omit({ id: true, date: true });
// Use Zod to update the expected types
const UpdateInvoice = formSchema.omit({ id: true, date: true });

export type State = {
    errors?: {
        customerId?: string[];
        amount?: string[];
        status?: string[];
    };
    message?: string | null;
};

export async function createInvoice(prevState: State, formData: FormData) { 
    const validatedFileds = CreateInvoice.safeParse({
        customerId: formData.get('customerId'),
        amount: formData.get('amount'),
        status: formData.get('status'),
    });

    if (!validatedFileds.success) {
        return {
            errors: validatedFileds.error.flatten().fieldErrors,
            message: 'Missing Fields. Failed to Create Invoice.',
        };
    }
    const { amount, customerId, status } = validatedFileds.data;
    const amountInCents = amount * 100;
    const date = new Date().toISOString().split('T')[0];
    // console.log(rawFormData)

    try {
    await sql`
      INSERT INTO invoices (customer_id, amount, status, date)
      VALUES (${customerId}, ${amountInCents}, ${status}, ${date})
    `;
  } catch (error) {
    // We'll log the error to the console for now
    console.error(error);
  }

    revalidatePath('/dashboard/invoices');
    redirect('/dashboard/invoices');
}

export async function updateInvoice(
  id: string,
  prevState: State,
  formData: FormData,
) {
  const validatedFields = UpdateInvoice.safeParse({
    customerId: formData.get('customerId'),
    amount: formData.get('amount'),
    status: formData.get('status'),
  });
 
  if (!validatedFields.success) {
    return {
      errors: validatedFields.error.flatten().fieldErrors,
      message: 'Missing Fields. Failed to Update Invoice.',
    };
  }
 
  const { customerId, amount, status } = validatedFields.data;
  const amountInCents = amount * 100;
 
  try {
    await sql`
      UPDATE invoices
      SET customer_id = ${customerId}, amount = ${amountInCents}, status = ${status}
      WHERE id = ${id}
    `;
  } catch (error) {
    return { message: 'Database Error: Failed to Update Invoice.' };
  }
 
  revalidatePath('/dashboard/invoices');
  redirect('/dashboard/invoices');
}

export async function deleteInvoice(id: string) {
  throw new Error('Failed to Delete Invoice');
  await sql`
    DELETE FROM invoices
    WHERE id = ${id}
  `;
 
  revalidatePath('/dashboard/invoices');
}

export async function authenticate(
  prevState: string | undefined,
  formData: FormData,
) {
  try {
    await signIn('credentials', formData);
  } catch (error) {
    if (error instanceof AuthError) {
      switch (error.type) {
        case 'CredentialsSignin':
          return 'Invalid credentials.';
        default:
          return 'Something went wrong.';
      }
    }
    throw error;
  }
}