import type { InvoicePoolStatus } from "../api/invoicePool";
import { formatInvoiceOcrErrorMessage } from "./invoiceOcr";

type InvoiceDisplayLike = {
  status?: string | null;
  invoiceCode?: string | null;
  invoiceNumber?: string | null;
  invoiceDate?: string | null;
  sellerName?: string | null;
  originalName?: string | null;
  unavailableReason?: string | null;
  unavailableMessage?: string | null;
  availabilityReason?: string | null;
  availabilityMessage?: string | null;
  archivedReason?: string | null;
  reason?: string | null;
  message?: string | null;
  ocrLastError?: string | null;
};

const INVOICE_STATUS_LABELS: Record<InvoicePoolStatus, string> = {
  pending_ocr: "识别中",
  ocr_failed: "识别失败",
  available: "可添加",
  bound: "已添加",
  archived: "已归档/已报销",
};

export function resolveInvoiceStatusLabel(status: string | null | undefined) {
  return status && status in INVOICE_STATUS_LABELS
    ? INVOICE_STATUS_LABELS[status as InvoicePoolStatus]
    : "未知状态";
}

export function formatInvoiceDisplayTitle(invoice: InvoiceDisplayLike | null | undefined) {
  if (!invoice) {
    return "未识别发票";
  }

  if (invoice.invoiceCode || invoice.invoiceNumber) {
    return `${invoice.invoiceCode || "无代码"}-${invoice.invoiceNumber || "无号码"}`;
  }

  return invoice.sellerName || invoice.originalName || "未识别发票";
}

function looksLikeMachineMessage(message: string) {
  return /^[a-z0-9_:. -]+$/i.test(message) && /[a-z]/i.test(message);
}

function resolveReasonMessage(reason: string | null | undefined) {
  if (!reason) {
    return "";
  }

  if (/duplicate/i.test(reason)) {
    return "已识别出相同发票，不能重复添加。";
  }

  if (/used_complete|used|archived/i.test(reason)) {
    return "该发票已报销或归档，不能再次添加。";
  }

  if (/bound|linked/i.test(reason)) {
    return "该发票已添加到其他单据，不能重复添加。";
  }

  if (/pending/i.test(reason)) {
    return "发票正在识别，完成后会自动刷新。";
  }

  if (/failed|missing_required_fields/i.test(reason)) {
    return formatInvoiceOcrErrorMessage(reason);
  }

  return "";
}

export function resolveInvoiceUserMessage(invoice: InvoiceDisplayLike | null | undefined) {
  if (!invoice) {
    return "该发票暂不可添加，请稍后刷新。";
  }

  const explicitMessage = invoice.unavailableMessage || invoice.availabilityMessage || invoice.message || "";
  if (explicitMessage && !looksLikeMachineMessage(explicitMessage)) {
    return explicitMessage;
  }

  const reasonMessage =
    resolveReasonMessage(explicitMessage) ||
    resolveReasonMessage(invoice.unavailableReason) ||
    resolveReasonMessage(invoice.availabilityReason) ||
    resolveReasonMessage(invoice.reason) ||
    resolveReasonMessage(invoice.archivedReason);
  if (reasonMessage) {
    return reasonMessage;
  }

  if (invoice.ocrLastError) {
    const errorMessage = formatInvoiceOcrErrorMessage(invoice.ocrLastError);
    return /重试|重新上传|人工处理/.test(errorMessage)
      ? errorMessage
      : `${errorMessage} 可删除后重新上传。`;
  }

  switch (invoice.status) {
    case "pending_ocr":
      return "发票正在识别，完成后会自动刷新。";
    case "available":
      return "可添加到当前报销单。";
    case "bound":
      return "该发票已添加到报销单，草稿或驳回状态可移除。";
    case "archived":
      return "该发票已归档或已报销，不能再次添加。";
    case "ocr_failed":
      return "识别失败，可删除后重新上传。";
    default:
      return "该发票暂不可添加，请稍后刷新。";
  }
}

export function resolveInvoiceNextStepText(invoice: InvoiceDisplayLike | null | undefined) {
  if (!invoice?.status) {
    return "";
  }

  if (invoice.status === "available") {
    return "可添加到当前报销单。";
  }

  if (invoice.status === "bound") {
    return "已添加到报销单，草稿或驳回状态可移除。";
  }

  return resolveInvoiceUserMessage(invoice);
}