/** Required Node.js modules */
const Express = require('express');
const Joi = require('joi')
const joiMiddleware = require('express-joi-validation').createValidator({})
const Prisma = require('prisma/prisma-client');
/** Instantiate Prisma client */
const prisma = new Prisma.PrismaClient();

/** Supplier validation schema for Joi */
const supplierSchema = Joi.object({
    Id: Joi.number().greater(0),
    name: Joi.string().alphanum().min(1).max(191).required(),
    contact: Joi.string().alphanum().min(1).max(191).required(),
    email: Joi.string().email().max(191).required(),
    phone_num: Joi.string().length(10).pattern(/^[0-9]+$/).required(),
    address: Joi.string().alphanum().min(1).max(191).required(),
  });

/** Initialize Express */
const Express = require('express');
app.use(Express.json());
const port = 3000;

/** Routes */
app.get('/', (req, res) => {
res.send("Hello, API server!");
});







/** Create a new supplier and write it to MySQL */
app.post("/supplier/create", joiMiddleware.query(supplierSchema), async (req, res) => {
    try {
      /** Use Prisma to write the data to our MySQL database */
      res.body = await prisma.supplier.create({
        data: {
          name: req.body.name,
          contact: req.body.contact,
          email: req.body.email,
          phone_num: req.body.phone_num,
          address: req.body.address,
        }
      });
    /** Send a response telling the user our data has been written */
    res.status(200).send({"message": "OK"});
    }
    /** If Prisma fails to write to the MySQL database */
    /** Catch the error and send it as our response */
    catch (err) {
      res.status(500).send(err);
    }
  });



/** Get a supplier by name, return the object in our response */
app.get('/supplier', async (req, res) => {
    try {
      const supplier = await prisma.supplier.findUnique({
        where: {
          name: req.body.name,
        }
      });
      /** Send the Supplier object as our response */
      res.status(200).send({"object": supplier});
    }
    /** When Prisma fails to read from database, catch the error and send it as our response */
    catch (err) {
      res.status(500).send(err);
    }
  });


/** Update an existing supplier */
app.patch("/supplier/update", joiMiddleware.query(supplierSchema), async (req, res) => {
    try {
      /** Use Prisma to write the data to our MySQL database */
      await prisma.supplier.update({
        where: {
          id: req.body.id,
        },
        data: {
          name: req.body.name,
          contact: req.body.contact,
          email: req.body.email,
          phone_num: req.body.phone_num,
          address: req.body.address,
       }
     });
     /** Send a response telling the user our data has been written */
     res.status(200).send({"message": "OK"});
    }
  /** When Prisma fails to write to database, catch the error and send it as response */
    catch (err) {
      res.status(500).send(err);
    }
  })



/** Delete a supplier with a given name */
app.delete('/supplier/delete', joiMiddleware.query(supplierSchema), async (req, res) => {
    try {
      const supplier = await prisma.supplier.delete({
        where: {
          name: req.body.name,
        }
      });
      res.status(200).send({"message": "deleted OK"});
    }
    /** If Prisma fails to delete the object, catch the error and send it as response */
    catch (err) {
      res.status(500).send(err);
    }
  });




/** Server */
app.listen(port, () => {
console.log('API listening on localhost: ${port}');
});