test

src/command_exit.ts

@@ -0,0 +1,7 @@
+import type { State } from "./state.js";
+
+export function commandExit(state: State) {
+  console.log('Closing the Pokedex... Goodbye!');
+  state.readline.close()
+  process.exit(0)
+}

src/command_help.ts

@@ -0,0 +1,10 @@
+import type { State } from "./state.js";
+
+export function commandHelp(state: State) {
+  const commands = state.commands;
+  let finalString = 'Welcome to the Pokedex!\nUsage: \n\n'
+  for (const command of Object.values(commands)) {
+    finalString += `${command.name}: ${command.description}\n`
+  }
+  console.log(finalString);
+}

src/commands.ts

@@ -0,0 +1,20 @@
+import { commandHelp } from "./command_help.js";
+import { commandExit } from "./command_exit.js";
+
+import type { CLICommand } from "./state.js";
+
+export function getCommands(): Record<string, CLICommand> {
+  return {
+    exit: {
+      name: "exit",
+      description: 'Exits the pokedex',
+      callback: commandExit,
+    },
+
+    help: {
+      name: "help",
+      description: 'Help command for pokedex',
+      callback: commandHelp,
+    },
+  };
+}

src/main.ts

@@ -1,7 +1,9 @@
 import { startREPL } from "./repl.js"
+import { initState } from "./state.js";
 
-function main() {
-  startREPL();
+async function main() {
+  const state = initState();
+  startREPL(state);
 
 }
 

src/repl.test.ts

@@ -1,4 +1,4 @@
-import { cleanInput } from "./repl.ts";
+import { cleanInput } from "./repl.js";
 import { describe, expect, test } from "vitest";
 
 describe.each([

src/repl.ts

@@ -1,4 +1,41 @@
-export function cleanInput(input: string): string[] {
-  const lowercaseString = input.toLowerCase();
-  return lowercaseString.trim().split(" ");
+import type { CLICommand, State } from './state.js';
+
+
+export function startREPL(state: State) {
+  state.readline.prompt();
+
+  state.readline.on("line", async (input) => {
+    const words = cleanInput(input);
+    if (words.length === 0) {
+      state.readline.prompt();
+      return;
+    }
+
+    const commandName = words[0];
+
+    const cmd = state.commands[commandName];
+    if (!cmd) {
+      console.log(
+        `Unknown command: "${commandName}". Type "help" for a list of commands.`,
+      );
+      state.readline.prompt();
+      return;
+    }
+
+    try {
+      cmd.callback(state);
+    } catch (e) {
+      console.log(e);
+    }
+
+    state.readline.prompt();
+  });
+}
+
+export function cleanInput(input: string): string[] {
+  return input
+    .toLowerCase()
+    .trim()
+    .split(" ")
+    .filter((word) => word !== "");
 }

src/state.ts

@@ -0,0 +1,28 @@
+import { createInterface, type Interface } from "node:readline";
+import { stdin, stdout } from 'node:process'
+import { getCommands } from "./commands.js";
+
+export type CLICommand = {
+  name: string,
+  description: string,
+  callback: (state: State) => void;
+}
+
+export type State = {
+  readline: Interface,
+  commands: Record<string, CLICommand>;
+}
+
+export function initState() {
+  const rl = createInterface({
+    input: stdin,
+    output: stdout,
+    prompt: 'Pokedex > ',
+  });
+
+  return {
+    readline: rl,
+    commands: getCommands(),
+  };
+
+}