import type { BlockView as HostBlockView } from '../../../src/codeReader/blockView'
import type { BlockView } from './types'
import { describe, expect, it } from 'vitest'
import { toBlockViews } from '../../../src/codeReader/blockView'
import { pageBlocks } from '../../../src/codeReader/editor/pageBlocks'
import { createPythonAdapter } from '../../../src/codeReader/languages/python'
import { WASM_DIR, withBlocks } from '../../../src/codeReader/testSupport'
import { pythonZhTranslator } from '../../../src/codeReader/translators/pythonZh'
import { placementOf } from './placement'

const py = createPythonAdapter(WASM_DIR)

async function views(source: string): Promise<HostBlockView[]> {
  return withBlocks(py, 'python', source, blocks => toBlockViews(blocks, { source, language: py, markers: [] }, pythonZhTranslator))
}

function flatten<T extends { children: T[] }>(list: T[]): T[] {
  return list.flatMap(block => [block, ...flatten(block.children)])
}

function byId(blocks: BlockView[]): Map<string, BlockView> {
  return new Map(flatten(blocks).map(block => [block.id, block]))
}

/** 一块自己的样子（不连子块）：子块变了不算它变了 */
function own({ children: _, ...rest }: BlockView): Omit<BlockView, 'children'> {
  return rest
}

const SOURCE = [
  'import os',
  '',
  'def helper(value):',
  '    return value + 1',
  '',
  'class Store:',
  '    def load(self, key):',
  '        if key:',
  '            return os.getenv(key)',
  '        return None',
  '',
  'LIMIT = 3',
].join('\n')

describe('块在文件里的位置：扩展端记成相对的，页面累加回来', () => {
  it('每块累加出来的首行、尾行、开头的下标同扩展端的一样；块里的下标加上块的开头就是文件里的', async () => {
    const host = await views(SOURCE)
    const placement = placementOf(pageBlocks(host, SOURCE))
    const lineStarts = SOURCE.split('\n').map((_, line, lines) => lines.slice(0, line).join('\n').length + (line > 0 ? 1 : 0))
    for (const block of flatten(host)) {
      expect(placement.of(block.id), block.id).toEqual({ offset: lineStarts[block.startLine], line: block.startLine, endLine: block.endLine })
    }
    const page = byId(pageBlocks(host, SOURCE))
    for (const block of flatten(host).filter(block => block.defines)) {
      const base = placement.of(block.id)!.offset
      const defines = page.get(block.id)!.defines!
      expect(SOURCE.slice(base + defines.startIndex, base + defines.endIndex), block.id).toBe(SOURCE.slice(block.defines!.startIndex, block.defines!.endIndex))
    }
  })

  it('靠前的一块里改了一个字：只有那块变了，包着它的块只是长了一个字，后面的块发出去一模一样', async () => {
    const edited = SOURCE.replace('value + 1', 'value + 10')
    const before = byId(pageBlocks(await views(SOURCE), SOURCE))
    const after = byId(pageBlocks(await views(edited), edited))
    const changed = [...after.keys()].filter(id => JSON.stringify(own(after.get(id)!)) !== JSON.stringify(own(before.get(id)!)))
    expect(changed).toEqual(['1', '1.0'])
    expect(own(after.get('1')!)).toEqual({ ...own(before.get('1')!), span: { ...before.get('1')!.span, length: before.get('1')!.span.length + 1 } })
  })

  it('上面多了几行：只有紧跟在后面的那块离前一块远了，其余块发出去一模一样，累加出来的位置都往后挪', async () => {
    const shifted = SOURCE.replace('import os\n', 'import os\n\n\n')
    const old = pageBlocks(await views(SOURCE), SOURCE)
    const page = pageBlocks(await views(shifted), shifted)
    const before = byId(old)
    const after = byId(page)
    const changed = [...after.keys()].filter(id => JSON.stringify(own(after.get(id)!)) !== JSON.stringify(own(before.get(id)!)))
    expect(changed).toEqual(['1'])
    expect(after.get('1')!.span).toEqual({ ...before.get('1')!.span, lineGap: before.get('1')!.span.lineGap + 2, gap: before.get('1')!.span.gap + 2 })
    for (const id of [...after.keys()].filter(id => id !== '0')) {
      const was = placementOf(old).of(id)!
      expect(placementOf(page).of(id), id).toEqual({ offset: was.offset + 2, line: was.line + 2, endLine: was.endLine + 2 })
    }
  })
})