import { describe, it, expect, beforeEach, vi } from 'vitest'
import { createCategoryDownloadConfig } from './download'
import type { CategoryWidgetData } from './types'

const data: CategoryWidgetData = [
  [
    { name: 'a', value: 1 },
    { name: 'b', value: 2 },
  ],
  [{ name: 'a', value: 10 }],
]

let csvText = ''

beforeEach(() => {
  csvText = ''
  vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:mock')
  vi.spyOn(URL, 'revokeObjectURL').mockImplementation(() => undefined)
  const RealBlob = global.Blob
  vi.stubGlobal(
    'Blob',
    class extends RealBlob {
      constructor(parts: BlobPart[], opts?: BlobPropertyBag) {
        csvText = typeof parts[0] === 'string' ? parts[0] : ''
        super(parts, opts)
      }
    },
  )
})

describe('createCategoryDownloadConfig', () => {
  it('CSV-only by default', () => {
    expect(
      createCategoryDownloadConfig({ filename: 'c', getData: () => data }).map(
        (i) => i.id,
      ),
    ).toEqual(['csv'])
  })

  it('CSV item carries the canonical icon and short label', () => {
    const item = createCategoryDownloadConfig({
      filename: 'c',
      getData: () => data,
    }).find((i) => i.id === 'csv')!
    expect(item.label).toBe('CSV')
    expect(item.icon).toBeTruthy()
  })

  it('prepends PNG when getCaptureEl is provided', () => {
    const items = createCategoryDownloadConfig({
      filename: 'c',
      getData: () => data,
      getCaptureEl: () => document.createElement('div'),
    })
    expect(items.map((i) => i.id)).toEqual(['png', 'csv'])
  })

  it('CSV resolve emits series × items with default names', async () => {
    const items = createCategoryDownloadConfig({
      filename: 'c',
      getData: () => data,
    })
    const handle = await items.find((i) => i.id === 'csv')!.resolve()
    expect(handle.filename).toBe('c.csv')
    expect(csvText).toBe(
      'series,name,value\nseries_1,a,1\nseries_1,b,2\nseries_2,a,10',
    )
  })

  it('CSV honours supplied seriesNames', async () => {
    const items = createCategoryDownloadConfig({
      filename: 'c',
      getData: () => data,
      seriesNames: ['baseline', 'override'],
    })
    await items.find((i) => i.id === 'csv')!.resolve()
    expect(csvText.split('\n')[1]).toBe('baseline,a,1')
    expect(csvText.split('\n')[3]).toBe('override,a,10')
  })
})