export interface Operation {
  op: string
  [key: string]: any
}

export interface PrintResult {
  ok: boolean
  msg?: string
  error?: string
  code?: string
  raw?: string
}

export function usePrintQueue() {
  const operations = useState<Operation[]>('printQueue', () => [])
  const result = useState<PrintResult>('printResult', () => ({ ok: true, msg: 'Listo.' }))
  const loading = useState('printLoading', () => false)

  function addOperations(ops: Operation[]) {
    if (Array.isArray(ops) && ops.length) {
      operations.value = [...operations.value, ...ops]
    }
  }

  function updateOperation(index: number, op: Operation) {
    operations.value = operations.value.map((o, i) => i === index ? op : o)
  }

  function removeOperation(index: number) {
    operations.value = operations.value.filter((_, i) => i !== index)
  }

  function moveOperation(from: number, direction: 'up' | 'down') {
    const to = direction === 'up' ? from - 1 : from + 1
    if (to < 0 || to >= operations.value.length) return

    const arr = [...operations.value]
    ;[arr[from], arr[to]] = [arr[to], arr[from]]
    operations.value = arr
  }

  function clearQueue() {
    operations.value = []
  }

  function loadFromTemplate(ops: Operation[]) {
    operations.value = JSON.parse(JSON.stringify(ops))
  }

  async function sendToPrinter() {
    if (operations.value.length === 0) return

    loading.value = true
    try {
      result.value = await $fetch('/api/print', {
        method: 'POST',
        body: { operations: operations.value }
      })
    } catch (error: any) {
      result.value = {
        ok: false,
        error: error.message || 'Error al enviar a la impresora'
      }
    } finally {
      loading.value = false
    }
  }

  return {
    operations: readonly(operations),
    result: readonly(result),
    loading: readonly(loading),
    addOperations,
    updateOperation,
    removeOperation,
    moveOperation,
    clearQueue,
    loadFromTemplate,
    sendToPrinter
  }
}