import { calculateCrcHexInput, calculateCrcReport, type CrcWorkerRequest, type CrcWorkerResponse } from '@/lib/crcWorker'
import { getFirmwareFormat, MAX_FIRMWARE_FILE_SIZE, parseFirmwareContent } from '@/lib/firmware'
import type { DataBlock } from '@/lib/intelHex'

const workerScope = globalThis as unknown as {
  onmessage: ((event: MessageEvent<CrcWorkerRequest>) => void) | null
  postMessage(message: CrcWorkerResponse): void
}

let firmwareBlocks: DataBlock[] | undefined

workerScope.onmessage = async (event) => {
  const request = event.data
  try {
    if (request.type === 'parse') {
      if (request.file.size === 0) throw new Error('文件为空')
      if (request.file.size > MAX_FIRMWARE_FILE_SIZE) throw new Error('文件不能超过 64 MiB')
      const format = getFirmwareFormat(request.file.name)
      const content = format === 'Intel HEX'
        ? await request.file.text()
        : new Uint8Array(await request.file.arrayBuffer())
      const parsed = parseFirmwareContent(request.file.name, content)
      firmwareBlocks = parsed.blocks
      workerScope.postMessage({
        type: 'parsed',
        id: request.id,
        format: parsed.format,
        totalBytes: parsed.totalBytes,
        blockCount: parsed.blocks.length,
        warnings: parsed.warnings,
      })
      return
    }
    if (request.type === 'calculate-hex') {
      workerScope.postMessage({
        type: 'calculated-hex',
        id: request.id,
        ...calculateCrcHexInput(request.input, request.parameters),
      })
      return
    }
    if (!firmwareBlocks) throw new Error('请先选择 BIN 或 Intel HEX 文件')
    workerScope.postMessage({ type: 'calculated', id: request.id, ...calculateCrcReport(firmwareBlocks, request.parameters) })
  } catch (reason) {
    workerScope.postMessage({
      type: 'error',
      id: request.id,
      operation: request.type,
      error: reason instanceof Error ? reason.message : 'CRC 计算失败',
    })
  }
}