main.js

const { argv } = require("process");
const assert = require("assert");
const { Client } = require("pg");
require("dotenv").config();

argv.splice(0, 2);
assert(
  argv.length == 1 || argv.length == 2,
  "no of input args must be less than 2"
);

//db
const client = new Client({
  host: process.env.PG_HOST,
  port: process.env.PG_PORT,
  user: process.env.PG_USER,
  password: process.env.PG_PASSWORD,
  database: process.env.PG_DATABASE,
});
console.log(`client made`);

const logAllOptions = () => {
  console.log(`Options:
    --new to add a new todo item
    --list [all|pending|done] to list the todo items
    --done [id] to update a todo item
    --delete [id] to delete a todo item
    --help to list all the available options
    --version to print the version of the application`);
};

const logAppVersion = () => {
  const ver = require("./package.json").version;
  console.log(ver);
};

//   db funcs
const insertItem = async (todoItem) => {
  await client.connect();

  try {
    const res = await client.query(
      `INSERT INTO todos (todo, status) VALUES ($1, $2);`,
      [todoItem, "pending"]
    );
  } catch (e) {
    console.log("db insertion error", e);
  } finally {
    await client.end();
  }

  console.log(`added the todo - "${todoItem}"`);
};

const logTodosAccToFormat = async (opt) => {
  await client.connect();
  let res = null;

  try {
    if (opt === "all") {
      res = await client.query(`SELECT * FROM todos;`);
    } else {
      res = await client.query(`SELECT * FROM todos WHERE status = $1;`, [opt]);
    }
  } catch (e) {
    console.log("db read error: ", e);
  } finally {
    await client.end();
  }

  console.table(res.rows);
};

const updateTodoAsDone = async (id) => {
  await client.connect();

  try {
    const res = await client.query(
      `UPDATE todos SET status = $1 WHERE id = $2;`,
      ["done", id]
    );
  } catch (e) {
    console.log("db updating error: ", e);
  } finally {
    await client.end();
  }

  console.log(`modified the todo with id: "${id}" as done`);
};

const deleteTodo = async (id) => {
  await client.connect();

  try {
    const res = await client.query(`DELETE FROM todos WHERE id = $1`, [id]);
  } catch (e) {
    console.log("db row deleting error: ", e);
  } finally {
    await client.end();
  }

  console.log(`deleted the todo with id: ${id}`);
};

const init = async () => {
  console.log(`init started`);

  switch (argv[0]) {
    case "--new":
      console.log(`inserting item ${argv[1]}`);
      await insertItem(argv[1]);
      break;
    case "--list":
      assert(["all", "pending", "done"].includes(argv[1]));
      console.log(`listing todos acc to format - ${argv[1]}`);
      logTodosAccToFormat(argv[1]);
      break;
    case "--done":
      console.log(`updating a todo item as done - id: ${argv[1]}`);
      updateTodoAsDone(argv[1]);
      break;
    case "--delete":
      console.log(`deleting a todo item -id: ${argv[1]}`);
      deleteTodo(argv[1]);
      break;
    case "--help":
      logAllOptions();
      break;
    case "--version":
      logAppVersion();
      break;
    default:
      console.log(`Pls enter a valid command - not doing anything`);
  }
};

init();