import { ApiCode } from '@/config'
import type { ApiResponse } from '@/types/api'
import type { VaultListItem, VaultTransactionItem } from '@/types/vault'
import { http, postJson } from './http'

export function fetchVaultsList() {
  return postJson<VaultListItem[]>('/vaultody/vaults/list', {})
}

export interface FetchVaultTransactionsBody {
  vaultId?: string | number | null
  /** 页码，从 1 开始 */
  page?: number
  pageSize?: number
}

export interface VaultTransactionsResult {
  list: VaultTransactionItem[]
  /** 总条数，用于分页；若后端暂未返回可先不传，前端会按当前页条数展示 */
  total?: number
}

function buildVaultTransactionsPayload(body: FetchVaultTransactionsBody): Record<string, unknown> {
  const payload: Record<string, unknown> = {}
  if (body.vaultId != null) payload.vaultId = body.vaultId
  if (body.page != null) payload.page = body.page
  if (body.pageSize != null) payload.pageSize = body.pageSize
  return payload
}

export function fetchVaultTransactions(body: FetchVaultTransactionsBody = {}) {
  return postJson<VaultTransactionsResult>('/vaultody/vaults/transactions', buildVaultTransactionsPayload(body))
}

function parseFilenameFromContentDisposition(cd: string | undefined): string | null {
  if (!cd) return null
  const m = /filename\*=UTF-8''([^;\n]+)|filename="?([^";\n]+)"?/i.exec(cd)
  const raw = m?.[1] ?? m?.[2]
  if (!raw) return null
  try {
    return decodeURIComponent(raw.trim())
  } catch {
    return raw.trim()
  }
}

async function tryParseJsonErrorBlob(blob: Blob): Promise<string | null> {
  const text = await blob.text()
  try {
    const json = JSON.parse(text) as ApiResponse
    if (typeof json.code === 'number' && json.code !== ApiCode.StatusOK) {
      return json.msg || 'Export failed'
    }
  } catch {
    /* not JSON */
  }
  return null
}

/** POST /vaultody/export，请求体与列表接口一致；成功返回文件 blob */
export async function exportVaultTransactions(
  body: FetchVaultTransactionsBody = {}
): Promise<{ blob: Blob; filename: string | null } | { error: string }> {
  const res = await http.post('/vaultody/export', buildVaultTransactionsPayload(body), {
    responseType: 'blob',
  })
  const raw = res.data
  if (!(raw instanceof Blob)) {
    const api = raw as ApiResponse
    return { error: api?.msg ?? 'Export failed' }
  }
  const blob = raw
  const ct = String(res.headers['content-type'] ?? res.headers['Content-Type'] ?? '').toLowerCase()
  if (ct.includes('application/json') || ct.includes('text/json')) {
    const err = await tryParseJsonErrorBlob(blob)
    return { error: err ?? 'Export failed' }
  }
  const filename = parseFilenameFromContentDisposition(
    res.headers['content-disposition'] ?? res.headers['Content-Disposition']
  )
  return { blob, filename }
}