import { describe, expect, it } from 'vitest'
import {
  findSlashToken,
  insertSlashTrigger,
  mergeSlashCommands,
  replaceSlashCommand,
} from './composerUtils'

describe('composerUtils', () => {
  it('finds slash token without trailing space', () => {
    expect(findSlashToken('/rev', 4)).toEqual({ start: 0, filter: 'rev' })
    expect(findSlashToken('hello /rev', 10)).toEqual({ start: 6, filter: 'rev' })
  })

  it('does not treat slash followed by a space as an active token', () => {
    expect(findSlashToken('/ review', 8)).toBeNull()
  })

  it('inserts a slash trigger without appending a trailing space', () => {
    expect(insertSlashTrigger('', 0)).toEqual({ value: '/', cursorPos: 1 })
    expect(insertSlashTrigger('hello', 5)).toEqual({ value: 'hello /', cursorPos: 7 })
  })

  it('replaces the current slash token with a command and one trailing separator', () => {
    expect(replaceSlashCommand('/rev', 4, 'review')).toEqual({
      value: '/review ',
      cursorPos: 8,
    })
  })

  it('merges fallback commands so built-in entries like /clear remain visible', () => {
    expect(
      mergeSlashCommands([
        { name: 'help', description: '' },
      ]),
    ).toEqual(
      expect.arrayContaining([
        { name: 'help', description: 'Show available commands' },
        { name: 'clear', description: 'Clear conversation history' },
      ]),
    )
  })

  it('keeps server-provided descriptions when they exist', () => {
    expect(
      mergeSlashCommands([
        { name: 'clear', description: 'Server description' },
      ]),
    ).toEqual(
      expect.arrayContaining([
        { name: 'clear', description: 'Server description' },
      ]),
    )
  })
})