import { describe, expect, it } from 'vitest'
import { applyFileMentionReplacement, findActiveFileMention } from './file-mention-autocomplete'

describe('findActiveFileMention', () => {
  it('detects mentions at the start of input', () => {
    const mention = findActiveFileMention({
      text: '@src/components',
      cursorIndex: '@src/components'.length,
    })
    expect(mention).toEqual({
      start: 0,
      end: '@src/components'.length,
      query: 'src/components',
    })
  })

  it('detects mentions in the middle of input using cursor position', () => {
    const text = 'read "@src/com" before merging'
    const cursorIndex = text.indexOf('"') + 9
    const mention = findActiveFileMention({
      text,
      cursorIndex,
    })
    expect(mention).toEqual({
      start: text.indexOf('@'),
      end: cursorIndex,
      query: 'src/com',
    })
  })

  it('returns null when cursor is outside the mention token', () => {
    const text = 'please review @src/components now'
    const mention = findActiveFileMention({
      text,
      cursorIndex: text.length,
    })
    expect(mention).toBeNull()
  })
})

describe('applyFileMentionReplacement', () => {
  it('replaces only the active @query segment with a quoted relative path', () => {
    const text = 'open @src/com next'
    const next = applyFileMentionReplacement({
      text,
      mention: { start: 5, end: 13, query: 'src/com' },
      relativePath: 'src/components/chat.tsx',
    })
    expect(next).toBe('open "src/components/chat.tsx" next')
  })

  it('escapes double quotes in replacement path', () => {
    const text = '@foo'
    const next = applyFileMentionReplacement({
      text,
      mention: { start: 0, end: 4, query: 'foo' },
      relativePath: 'src/"quoted".ts',
    })
    expect(next).toBe('"src/\\"quoted\\".ts"')
  })
})