import { describe, expect, it } from 'vitest'
import { artifactLabel, collectionOf, dayLabel, didOf, relativeTime, rkeyOf, summarize } from './format.js'

const NOW = '2026-07-25T14:18:00Z'

describe('relativeTime', () => {
  it('reads in the unit a human would say out loud', () => {
    expect(relativeTime('2026-07-25T14:17:40Z', NOW)).toBe('now')
    expect(relativeTime('2026-07-25T14:12:00Z', NOW)).toBe('6m')
    expect(relativeTime('2026-07-25T11:30:00Z', NOW)).toBe('3h')
    expect(relativeTime('2026-07-21T09:14:00Z', NOW)).toBe('4d')
  })

  it('falls back to a date once "N days ago" stops being useful', () => {
    expect(relativeTime('2026-06-12T09:15:00Z', NOW)).toMatch(/Jun/)
  })

  it('never reports a future record as negative', () => {
    expect(relativeTime('2026-07-25T15:00:00Z', NOW)).toBe('now')
  })
})

describe('dayLabel', () => {
  it('names the two days a human has words for', () => {
    expect(dayLabel(NOW, NOW)).toBe('Today')
    expect(dayLabel('2026-07-24T09:00:00Z', '2026-07-25T09:00:00Z')).toBe('Yesterday')
    expect(dayLabel('2026-07-21T09:00:00Z', NOW)).toMatch(/Jul/)
  })
})

describe('AT URI parts', () => {
  const uri = 'at://did:plc:qv7hjr2mzk4x/com.disnetdev.radial.goal/3lbq2xk7wf22h'
  it('splits into the pieces a route and a chip need', () => {
    expect(didOf(uri)).toBe('did:plc:qv7hjr2mzk4x')
    expect(collectionOf(uri)).toBe('com.disnetdev.radial.goal')
    expect(rkeyOf(uri)).toBe('3lbq2xk7wf22h')
  })
})

describe('artifactLabel', () => {
  const body = '## Context\n\n0004 chose polling. It was right at the time.'

  it('uses the artifact’s own title, whitespace and all', () => {
    expect(artifactLabel({ title: '  0008 · Jetstream first  ', body })).toBe('0008 · Jetstream first')
  })

  it("falls back to the body's heading for a record written before titles existed", () => {
    // Immutable and un-retitleable, so this is the row a real space keeps showing for years. It is
    // display-only — nothing persists it, and nothing treats it as protocol data.
    expect(artifactLabel({ body })).toBe('Context')
    expect(artifactLabel({ title: '   ', body })).toBe('Context')
  })

  it('uses the derived summary when a legacy body has no heading', () => {
    const headingless = '0004 chose polling. It was right at the time.'
    expect(artifactLabel({ body: headingless })).toBe(summarize(headingless))
  })

  it('truncates a long-but-valid title rather than letting it run the width of a row', () => {
    // 200 characters is valid on the wire; a row is narrower than that.
    const label = artifactLabel({ title: 'x'.repeat(200), body }, 80)
    expect(label.length).toBe(80)
    expect(label.endsWith('…')).toBe(true)
  })
})

describe('summarize', () => {
  // The legacy fallback: an artifact written before `title` existed has no name of its own, so a
  // row's one line has to come out of the prose.
  it('skips headings and takes the first sentence', () => {
    expect(summarize('## Approach\n\nAdd a `/queue` route. It filters the index.')).toBe(
      'Add a /queue route.',
    )
  })

  it("skips an ADR's Status: line, which is a convention rather than a summary", () => {
    expect(summarize('Status: accepted · supersedes 0004\n\n## Context\n\n0004 chose polling.')).toBe(
      '0004 chose polling.',
    )
  })

  it('truncates rather than letting a paragraph run the width of a row', () => {
    const long = `${'word '.repeat(60)}end.`
    expect(summarize(long).length).toBeLessThanOrEqual(140)
    expect(summarize(long).endsWith('…')).toBe(true)
  })

  it('returns nothing for a body that is only headings', () => {
    expect(summarize('## Only a heading')).toBe('')
  })

  // A plan opens with its own `# ` title, and the row already shows the artifact's type.
  it("skips a body's own title and the fence under it", () => {
    expect(summarize('# Plan: implement multiply\n\n```js\nconst x = 1\n```\n\nReplace the stub.')).toBe(
      'Replace the stub.',
    )
  })
})