import { reactive } from 'vue'

import { consumeSigningToken, uploadSigningSignature } from '@/api'
import type { SignatureUploadResponse } from '@/api/types'
import type { SignFlowState } from '@/types/signing'

const initialState: SignFlowState = {
  mode: 'mock',
  status: 'idle',
  patientName: '张*',
  visitNo: 'MZ20260827018',
  documentTitle: '儿科急诊特殊检查知情同意书',
  taskNo: 'CT-20260827-001',
  taskId: '',
  deliveryId: '',
  uploadToken: '',
  channel: '',
  consentAccepted: false,
  signerName: '',
  relation: '',
  signatureCaptured: false,
  submittedAt: '',
  backendStatus: '',
  pipelineId: '',
  uploadResult: null,
  errorMessage: '',
}

export const signingState = reactive<SignFlowState>({ ...initialState })

export function resetSignFlow() {
  Object.assign(signingState, {
    ...initialState,
    uploadResult: null,
  })
}

function getErrorMessage(error: unknown) {
  return error instanceof Error ? error.message : '签署链接验证失败，请联系现场医务人员。'
}

export async function initializeSignFlow(token?: string) {
  resetSignFlow()

  const candidate = token?.trim()
  const shouldUseRealFlow = Boolean(candidate) || import.meta.env.VITE_USE_MOCK === 'false'

  signingState.mode = shouldUseRealFlow ? 'real' : 'mock'

  if (!shouldUseRealFlow) {
    signingState.status = 'ready'
    return true
  }

  if (!candidate) {
    signingState.status = 'blocked'
    signingState.errorMessage = '请使用短信或二维码中的有效签署链接进入。'
    return false
  }

  signingState.status = 'loading'

  try {
    const session = await consumeSigningToken({ token: candidate, channel: 'SMS' })

    signingState.taskId = session.taskId
    signingState.taskNo = session.taskId
    signingState.deliveryId = session.deliveryId
    signingState.uploadToken = session.uploadToken
    signingState.channel = session.channel
    signingState.documentTitle = '待签署知情同意文书'
    signingState.patientName = '患者信息待确认'
    signingState.visitNo = ''
    signingState.status = 'ready'
    return true
  } catch (error) {
    signingState.status = 'error'
    signingState.errorMessage = getErrorMessage(error)
    return false
  }
}

export async function submitRealSignature(input: {
  file: Blob
  signerName: string
  relation: NonNullable<SignFlowState['relation']>
  consentAccepted: boolean
}): Promise<SignatureUploadResponse> {
  if (signingState.mode !== 'real') {
    throw new Error('当前是演示签署流程')
  }

  if (
    !signingState.taskId ||
    !signingState.deliveryId ||
    !signingState.uploadToken ||
    !input.consentAccepted
  ) {
    throw new Error('签署凭证或知情确认状态无效，请重新打开签署链接。')
  }

  signingState.status = 'submitting'
  signingState.errorMessage = ''

  try {
    const result = await uploadSigningSignature({
      taskId: signingState.taskId,
      deliveryId: signingState.deliveryId,
      uploadToken: signingState.uploadToken,
      file: input.file,
      metadata: JSON.stringify({
        signerName: input.signerName,
        relation: input.relation,
        consentAccepted: input.consentAccepted,
        signedAt: new Date().toISOString(),
      }),
    })

    signingState.signerName = input.signerName
    signingState.relation = input.relation
    signingState.consentAccepted = input.consentAccepted
    signingState.signatureCaptured = true
    signingState.submittedAt = new Date().toLocaleString('zh-CN')
    signingState.backendStatus = result.status
    signingState.pipelineId = result.pipelineId
    signingState.uploadResult = result
    signingState.uploadToken = ''
    signingState.status = 'submitted'
    return result
  } catch (error) {
    signingState.status = 'ready'
    signingState.errorMessage = getErrorMessage(error)
    throw error
  }
}