refactor: extract model configuration in separate file

The behavior is kept exactly the same but now allows for
easy and simple change of model used by changing or replacing model.ts

This approach is very flexible as Vercel AI SDK support many models
out of the box, and the difference is a few lines of code.

Author: borisyankov

packages/cali/src/cli.ts

@@ -2,7 +2,6 @@
 
 import 'dotenv/config'
 
-import { createOpenAI } from '@ai-sdk/openai'
 import { confirm, outro, select, spinner, text } from '@clack/prompts'
 import { CoreMessage, generateText } from 'ai'
 import * as tools from 'cali-tools'
@@ -12,22 +11,20 @@ import { retro } from 'gradient-string'
 import { z } from 'zod'
 
 import { reactNativePrompt } from './prompt.js'
-import { getApiKey } from './utils.js'
 
 const MessageSchema = z.union([
-  z.object({ type: z.literal('select'), content: z.string(), options: z.array(z.string()) }),
+  z.object({
+    type: z.literal('select'),
+    content: z.string(),
+    options: z.array(z.string()),
+  }),
   z.object({ type: z.literal('question'), content: z.string() }),
   z.object({ type: z.literal('confirmation'), content: z.string() }),
-  z.object({ type: z.literal('end') }),
+  z.object({ type: z.literal('end'), content: z.string() }),
 ])
 
 console.clear()
 
-process.on('uncaughtException', (error) => {
-  console.error(chalk.red(error.message))
-  console.log(chalk.gray(error.stack))
-})
-
 console.log(
   retro(`
   ██████╗ █████╗ ██╗     ██╗
@@ -49,37 +46,28 @@ console.log(
 
 console.log()
 
-const AI_MODEL = process.env.AI_MODEL || 'gpt-4o'
+import model from './model.js'
 
-const openai = createOpenAI({
-  apiKey: await getApiKey('OpenAI', 'OPENAI_API_K2EY'),
+const question = await text({
+  message: 'What do you want to do today?',
+  placeholder: 'e.g. "Build the app" or "See available simulators"',
 })
 
-async function startSession(): Promise<CoreMessage[]> {
-  const question = await text({
-    message: 'What do you want to do today?',
-    placeholder: 'e.g. "Build the app" or "See available simulators"',
-    validate: (value) => (value.length > 0 ? undefined : 'Please provide a valid answer.'),
-  })
-
-  if (typeof question === 'symbol') {
-    outro(chalk.gray('Bye!'))
-    process.exit(0)
-  }
-
-  return [
-    {
-      role: 'system',
-      content: 'What do you want to do today?',
-    },
-    {
-      role: 'user',
-      content: question,
-    },
-  ]
+if (typeof question === 'symbol') {
+  outro(chalk.gray('Bye!'))
+  process.exit(0)
 }
 
-let messages = await startSession()
+const messages: CoreMessage[] = [
+  {
+    role: 'system',
+    content: 'What do you want to do today?',
+  },
+  {
+    role: 'user',
+    content: question,
+  },
+]
 
 const s = spinner()
 
@@ -88,7 +76,7 @@ while (true) {
   s.start(chalk.gray('Thinking...'))
 
   const response = await generateText({
-    model: openai(AI_MODEL),
+    model,
     system: reactNativePrompt,
     tools,
     maxSteps: 10,
@@ -158,13 +146,13 @@ while (true) {
       case 'select':
         return select({
           message: data.content,
-          options: data.options.map((option) => ({ value: option, label: option })),
+          options: data.options.map((option) => ({
+            value: option,
+            label: option,
+          })),
         })
       case 'question':
-        return text({
-          message: data.content,
-          validate: (value) => (value.length > 0 ? undefined : 'Please provide a valid answer.'),
-        })
+        return text({ message: data.content })
       case 'confirmation': {
         return confirm({ message: data.content }).then((answer) => {
           return answer ? 'yes' : 'no'
@@ -174,8 +162,8 @@ while (true) {
   })()
 
   if (typeof answer !== 'string') {
-    messages = await startSession()
-    continue
+    outro(chalk.gray('Bye!'))
+    break
   }
 
   messages.push({

packages/cali/src/model.ts

@@ -0,0 +1,61 @@
+import 'dotenv/config'
+
+import { execSync } from 'node:child_process'
+
+import { createOpenAI } from '@ai-sdk/openai'
+import { confirm, text } from '@clack/prompts'
+import chalk from 'chalk'
+import dedent from 'dedent'
+
+const OPENAI_API_KEY =
+  process.env.OPENAI_API_KEY ||
+  (await (async () => {
+    let apiKey: string | symbol
+    do {
+      apiKey = await text({
+        message: dedent`
+          ${chalk.bold('Please provide your OpenAI API key.')}
+
+          To skip this message, set ${chalk.bold('OPENAI_API_KEY')} env variable, and run again. 
+          
+          You can do it in three ways:
+          - by creating an ${chalk.bold('.env.local')} file (make sure to ${chalk.bold('.gitignore')} it)
+            ${chalk.gray(`\`\`\`
+              OPENAI_API_KEY=<your-key>
+              \`\`\`
+            `)}
+          - by passing it inline:
+            ${chalk.gray(`\`\`\`
+              OPENAI_API_KEY=<your-key> npx cali
+              \`\`\`
+            `)}
+          - by setting it as an env variable in your shell (e.g. in ~/.zshrc or ~/.bashrc):
+            ${chalk.gray(`\`\`\`
+              export OPENAI_API_KEY=<your-key>
+              \`\`\`
+            `)},
+          `,
+      })
+    } while (typeof apiKey !== 'string')
+
+    const save = await confirm({
+      message: 'Do you want to save it for future runs in `.env.local`?',
+    })
+
+    if (save) {
+      execSync(`echo "OPENAI_API_KEY=${apiKey}" >> .env.local`)
+      execSync(`echo ".env.local" >> .gitignore`)
+    }
+
+    return apiKey
+  })())
+
+const AI_MODEL = process.env.AI_MODEL || 'gpt-4o'
+
+const openai = createOpenAI({
+  apiKey: OPENAI_API_KEY,
+})
+
+const model = openai(AI_MODEL)
+
+export default model